My name is Andrew Morgan. In this talk, I'll be presenting work done by myself in conjunction with Rafael Pass and Elaine Shea, which proves a lower bound in the security loss of black box reductions from adaptively multi-user secure message authentication codes and pseudo random functions to standard assumptions. Most of the audience is hopefully familiar with message authentication codes or MACs, which are a secret key primitive allowing messages to be securely tagged in such a way that an adversary without access to the key, even after being able to query tags for chosen messages is unable to forge an accepting tag for a new message. This allows messages to be securely authenticated by verifying using the key that the tag is indeed correct and corresponds to the message that was received. Pseudo random functions or PRFs are key indexed families of functions, which are surprisingly closely related to the tag generation algorithm for MACs. The definition of pseudo randomness requires that the output of the function, given a randomly chosen key, should be computationally indistinguishable from that of a truly random function by an adversary which may query the function on chosen inputs. In fact, it is relatively straightforward to see that MACs can be constructed from PRFs, since one can easily show that this notion of pseudo randomness implies unforgeability and hence a PRF can be used directly as a tagging algorithm for a MAC. Perhaps unsurprisingly, MACs and PRFs are some of the most ubiquitous and widely used cryptographic primitives in practice. PRFs are useful as a replacement for true random functions in many protocols, since true random functions are too expensive to instantiate. Meanwhile, MACs are useful in a great variety of protocols where authentication is needed, a notable example being the TLS protocol for authenticated key exchange. The fact that these primitives are used in settings with potentially tens or hundreds of millions of concurrent users highlights one of the shortcomings of the classical definitions of their security. These definitions only consider an adversary which can access and try to break a single instance of the primitive, that is a single key. But in practice, an adversary would be able to access many instances, and we would like to guarantee that this wouldn't help them to break any of them. To capture this, we'll be considering a stronger definition of security originally proposed by Bolare et al. in 1996 for PRFs and considered in several works since. This definition, which we'll call adaptive multi-user security, gives the adversary the ability to make queries to L of N different instances of a PRF, and additionally, to ask the challenger for the keys for up to all but one of those instances before finally trying to distinguish between the final instance of the PRF and a truly random function. We can easily think of an analogous definition for MACs where the adversary, after making tagging and key-opening queries to many different instances, must forge a tag for an unquery message on an instance whose key has not yet been revealed. The good news about this stronger definition is that it is quite easy to achieve. In fact, any PRF or MAC, which satisfies the classical definitions of security, already satisfies the respective definitions of adaptive multi-user security. This can be seen through a very simple reduction where an adversary against single-user security embeds their challenges into a randomly selected one of the relevant instances in a multi-user security game. That way, if a multi-user security adversary happens to choose the correct instance as the one to break, the single-user adversary will break security of its own instance as well. So it seems fairly straightforward to obtain an adaptive multi-user security by just constructing a primitive, which is classically secure, and relying on the reduction from multi-user to single-user security. However, as it turns out, this strategy leaves a lot to be desired in terms of the concrete level of multi-user security we can obtain given a certain level of single-user security. To reason about this, let's first quickly look at how we can quantify concrete security in the first place. Consider some black box reduction R from a primitive, such as our notion of adaptively multi-user secure MACs to some standard assumption C. Security of the primitive follows from the assertion that whenever there exists an adversary A that breaks the security of the primitive, the reduction R can use A as a black box to efficiently break the standard assumption C. And so, by contrapositive, security of C implies that no such adversary may exist. We'll think of the concrete security of a primitive or assumption as the amount of work or expected time needed for some machine M to break it, that is the time taken by M divided by the probability that M succeeds in the security gain. The most efficient reductions, then, are those where there's only a constant factor difference between the work required by the adversary and by the reduction, since, in that case, by the contrapositive, guaranteeing security of the primitive against, say, T-time adversaries, requires only security against C-times T-time adversaries for the assumption. We'll call these tight reductions. If instead there's a poly and factor difference, then we have what's known as a linear preserving reduction and weaker than that is the notion of a polynomial preserving reduction where the work needed to break the primitive is polynomial in the work needed to break the adversary. Anything worse than that is called weakly preserving. The important takeaway here is that tight and linear preserving reductions preserve asymptotic security. For instance, with a linear preserving reduction, security against poly of N times 2 to the N over 3 time adversaries for the assumption implies similarly security against poly of N times 2 to the N over 3 time adversaries for the primitive as well, which is ideal. With the polynomial preserving reduction on the other hand, we might need, say, 2 to the N time security for the assumption, which is probably unachievable, to guarantee the same poly of N times 2 to the N over 3 time security for the primitive. Since we care a lot about the level of concrete security of a primitive in practice, this really makes only linear preserving or tight reductions desirable for practical use. With that in mind, let's look back at our guessing reduction to see how well it preserves concrete security. Unfortunately, as it turns out, the answer is not very well. We can see that the single user security in this case requires L of N times as much work as the multi-user adversary. Since it requires the multi-user adversary to both succeed and pick the correct instance to break. So unless the number of keys L of N is a priori bounded, this reduction isn't linear preserving and doesn't preserve asymptotic security necessarily. Even looking from a practical perspective, the security loss is extremely significant when we consider the fact that there could be 2 to the 30 or 2 to the 40 instances in use at once. So the natural question to ask is, can we get more efficient reductions in this trivial guessing reduction? Specifically, towards constructing adaptively multi-user secure maps or PRFs from standard assumptions, can we either find a better multi-key to single key reduction than this one to avoid the security loss or find an alternative efficient reduction that bypasses single key security entirely? Actually, Ballari et al in 2016 answered this question positively by constructing a PRF with a nearly tight reduction. However, their reduction relies on the random oracle model whereas in our work, we will focus on reductions in the plain model. Meanwhile, for Max and the plain model, Batr et al answered this question in the positive by constructing an adaptively multi-user secure digital signature scheme with a linear preserving reduction. Notably, however, the signing algorithm in their construction is randomized. Ideally, we would like to have a similar result for deterministic signatures for Max as well, since randomness is fairly expensive to generate and represents a significant cost for a primitive as widely used and time sensitive as authentication. Indeed, for this and other reasons, we note that virtually all Max used in practice have deterministic tagging algorithms to say nothing of PRFs, which are deterministic functions by definition. To further focus, we note that PRFs also clearly store no internal state, another feature shared with virtually all practically used Max, albeit with the notable exception of GMAC. So, narrowing down to the most practically relevant notion of deterministic and stateless Max, we can ask our question again. And this time, in contrast to Batr et al, the earlier work of Chatterjee et al suggests a negative answer to this question, ruling out generic black box reductions, that is reductions that apply to any Mac from adaptive multi-user security to single user security of Max. But this still leaves open both the question of whether we can find a reduction for a specific Mac, and the question of whether we can bypass single user security and base adaptive multi-user security on standard reductions directly. In this work, we provide a strong negative answer to this question with our main result. A lower bound that rules out any linear preserving black box reduction from adaptive multi-user security of a deterministic and stateless Mac to any bounded round assumption. Specifically, we show that any assumption for which there does exist such a reduction is inherently insecure, and demonstrate how to break it with a meta reduction that uses the original reduction as a black box. Moreover, this approach will lower bound the concrete security loss of any such reduction by omega square root of L of N. This will rule out linear preserving reductions since L of N can be arbitrarily large, whereas a linear preserving reduction requires a security loss to be bounded above by an a priori fixed polynomial. Whether this bound is tight remains an open question. We also show as a corollary in the full version of our paper that the same bound applies to reductions from the adaptive multi-user security of digital signature schemes and PRFs to standard assumptions. The key takeaway then is that if we want constructions of Macs with efficient security reductions for the case of concurrent security with many users, we need to look towards either randomized constructions such as that of Potter et al, or towards stateful constructions such as GMAC. In the rest of the presentation, I'll go into more technical detail about the meta reduction paradigm and the approach we use to prove our main result. We prove our lower bound through, as I just said, the meta reduction paradigm, which was pioneered by Bonet and Venkatesan in 1998. Let's say we have some primitive PI for which we want to rule out reductions to standard assumptions. Next, imagine a perfect adversary A, which breaks PI with probability one, but does so inefficiently, say in super polynomial time. When we consider a black box reduction R that uses A to break an underlying assumption C, R will successfully break C with some significant non-negligible probability P of N. Of course, since R uses the inefficient adversary A, it definitely doesn't break C in polynomial time, so we're not quite done. If we instead create what's known as a meta reduction B, which efficiently simulates the interaction between R and A with probability close to one, say one minus Q of N, then B must break C with probability P of N minus Q of N, since its messages to C are, except with probability Q of N, identically distributed to those from the real reduction R, which breaks C with probability P of N. What this means is, if there exists any reduction R, such that P of N is large enough for P of N minus Q of N to be non-negligible, the meta reduction B breaks C, showing that C being secure implies that no such R can exist. Our starting point towards our main result is a meta reduction from the prequel to this work done by myself and pass in 2018, which rules out linear preserving reductions from unique digital signatures to standard assumptions. I'll talk through this at a high level before describing the non-trivial changes and additions needed to adapt it to our current result. For this meta reduction, the ideal adversary A, on receiving a public key from the reduction, begins by making a large number of signature queries for random messages. We refer to this number as L of N, since these queries will ultimately be the analog of the key opening queries to each instance in our final reduction. On receiving responses from the reduction R, A verifies using the public key that the responses are correct, aborting if not, and then uses brute force to forge a signature for a new message that likewise verifies with respect to the public key. It's fairly straightforward to see that this ideal adversary will break the security of the signature scheme with probability one. Of course, the next step is to create a meta reduction B, which efficiently simulates this interaction with probability close to one. B starts by making the signature queries and verifying the responses just as A does and will forge a signature for a new message M star if R gives valid responses. However, rather than brute forcing the forgery, B attempts to cheat by extracting the forgery from R itself. B will rewind the interaction with the reduction R many times, sending it the forgery target M star in place of each one of the signature queries in turn until one of two things happens. Either R gives a valid signature as a response, in which case B sends that as its forgery, or if B tries every possible query and fails to extract a response, B will abort and thus fail to efficiently emulate the interaction between R and A. The key lemma from our prior work bounds the probability with which B fails to emulate the interaction by roughly O of M squared of N over L of N, where M of N is the number of instances of the adversary, which can be run by the reduction, and L of N is, as before, the number of signature queries made by the adversary. The proof is out of scope for this talk, but at a high level, it follows from accounting argument, which bounds the number of sequences of messages where B fails to emulate A during every possible rewinding, with extra allowances made for rewindings that could prove problematic to B's functionality or running time. For instance, those involving communication with a challenger for C, hence the need for an a priori bound R of N and a number of rounds of communication, of the assumption C. The key takeaway from this is that like I mentioned before, if any black box reduction R to some assumption C succeeds with probability non-negligibly greater than this bound, when given the efficient adversary A against unique signatures, B breaks the assumption C in polynomial time, contradicting C's security. To show how this implies a lower bound for the security loss of R, observe first that A succeeds with probability one and that by the assumption that R runs at most M of N instances of A, R in the worst case takes M of N times as long to run as A does. We can then simply split the analysis into two cases. If R runs many instances of A, then we can just use the observation that the work ratio is at least M of N to conclude that the work ratio is sufficiently large. Otherwise, if R runs few instances of A, we can still conclude that the work ratio is at least M of N divided by the success probability of R, which by the bound we establish yields the same conclusion. And as before, since L of N can be an arbitrarily large polynomial, this rules out all linear preserving reductions from unique signatures to bounded round assumptions. So, bringing this back to the case of adaptive multi-user security of Macs, a first attempt at a meta reduction would be to try applying the technique we just described to the key opening queries in the security game. Given L of N different instances of a Mac, B could make key opening queries to all but one of the instances in a random order and then rewind, trying to query the key for the target instance in place of each of the other queries in turn until R responds correctly and finally using the extracted key to forge a tag for a random message. This sounds great at first, but if you think about it for a second, two problems emerge pretty quickly. First, unlike signature queries, which we could verify with the public key, we have no way to tell whether R is sending the correct responses to these key opening queries from just the key alone, which is a problem when we need to extract the correct key for the target instance to produce our forgery. Second, and relatedly, we haven't discussed the ideal and inefficient adversary A yet. A needs to be able to brute force a forgery, which is impossible to do without some way to internally verify whether a guess is correct. What we do to provide this internal verification is as follows. We have A and B additionally make some numbers, Q of N, of tagging queries on random messages to each instance before opening any keys. Then once R responds to a key opening query, we can check whether that key is consistent with the tagging queries we made. If it isn't, then the key is invalid and we can abort. Furthermore, A can use the queries made for the target instance to brute force a key to use for its forgery. Unfortunately, this approach isn't perfect since intuitively it's occasionally possible for an incorrect key to slip through and by pure coincidence agree with the right key in all of the Q of N tag queries. We can, however, show that the chance of this coincidence is fairly small. Specifically, we do so through this lemma. Let's say we have some pair of keys that produce the same output on our Q of N tag queries, then it's overwhelmingly likely that they will agree on most messages. What this means is that if during rewinding, the key recovered by B is consistent with the queries, but somehow different from the one A brute forced using the results of the queries, then it's likely that A and B will still end up with the same actual forgery. The proof is fairly straightforward. For any key pair that doesn't agree on most inputs, we can show that the probability of that pair agreeing on our Q of N random tag queries is exponentially small, even when we factor in the fact that there may be up to two to the two N possible key pairs. The fact that we can actually deal with this issue is interesting in and of itself since the one prior work that ran into this issue, specifically in the context of a meta reduction for authenticated encryption required key uniqueness as an explicit property of the primitive. That is that any two keys which agree on Q of N queries must agree over all inputs. In contrast, we show that we can use additional queries to guarantee that keys will still agree on the forgery target with high probability, even without a strict requirement for it. There's still an additional issue. There are some technical details concerning a rewinding lemma, which required that the forgery output by A or B has to be unique all of the time rather than just with high probability. At a high level, we need to show that the reduction R attempting to rewind the adversary A is pointless and will yield no additional information as rewinding by R can potentially blow up the running time or the failure probability of the meta reduction B in an uncontrollable way. However, if A or B could potentially output multiple different forgeries for a single set of tag queries, this is clearly not the case as R could attempt to rewind A to try to extract different forgeries from the same instance of A. So to deal with this, we need a variant of B that does guarantee a unique forgery. Now, we can't construct an efficient meta reduction that does this due to the key uniqueness issue we were having before. However, suppose we consider an inefficient meta reduction, say B prime, that does as follows. First, it acts as B does, making tag queries, opening everything but the target instance and then rewinding to try and extract a key. However, when it does recover a correct key, B prime will brute force all possible keys that agree with the tag queries for the target instance so that it can choose a deterministic one of those keys, say the lexicographically first of them. And since A is already an inefficient adversary, we can have A do this as well, so that B prime and A will do the same thing as long as the rewinding works and any key is recovered. Furthermore, if the key is recovered by A and B, agree with respect to the randomly generated forgery input X star, then B and B prime are identical since B prime recovers the same key that A will. So, we can use a hybrid argument to find the probability with which B fails to emulate A, by first going from A to B prime and considering the chance that they behave differently and then doing the same thing from B prime to B. Going from A to B prime, now that B prime gives us a unique forgery is actually a straightforward application of the lemma from the meta reduction for unique signatures. The only difference is that we're rewinding the order of the L of N key opening queries this time, rather than sequences of L of N plus one messages, so we lose the constant in the denominator. And going from B prime to B is just an application of the key uniqueness lemma I went over a few slides ago on each of the M of N different instances of the adversary A that R runs. Furthermore, because Q of N is a parameter, we can set it large enough in comparison to L of N, so that the chance of B prime and B behaving differently is minimal compared to the difference between A and B prime. So ultimately we get this bound in the probability that B's emulation of A fails. From here, we can essentially use the same argument as we used for unique signatures to bound the work ratio. Well, with the minor caveat that A no longer succeeds with exactly probability one as it did before. The reason for that goes back to key uniqueness and the fact that even with the additional tag queries added, A might still choose an incorrect key which agrees with the actual key in all of the queries. But by once again leveraging the key uniqueness lemma, we can still show that the success probability of A is high. So this has very little impact in the actual bound we achieve, especially because Q can be an arbitrarily large polynomial. In the end, we still rule out all linear preserving reductions, obtaining a bound virtually identical to that of our earlier result for unique signatures, though we note that whether either of these bounds is tight remains an interesting open question. So to summarize a result, we ruled out all linear preserving reductions from the adaptive multi-user security of a deterministic and stateless Mac to any of a wide variety of underlying assumptions. This result, as can be seen in the full version of our paper, also easily extends to reductions from adaptively multi-user secure digital signatures and PRFs, as well as to reductions to any assumption that has a stateless challenger even if there is no a priori bound in the number of rounds of communication. For instance, single user security of PRFs would be such an assumption. In addition, we used a key uniqueness lemma and a hybrid meta reduction to deal with the fact that unlike all prior meta reductions, our setting doesn't have a unique correspondence between ours responses to queries, in this case, the keys and the forgeries that our meta reduction outputs. This is a particular interest because even though the Macs we consider are being deterministic and stateless, technically unique relations, it suggests that one might in the future hope to use this or similar techniques to apply the meta reduction paradigm to even primitives that aren't unique, which so far hasn't been done even in a restricted setting. With that, I'll conclude my presentation. Thank you for listening.


Either lads and ladies it is petrifying pumpkins here, and I'm just making a very quick update video Because for firewall zero hour, obviously as you can see Just because I saw an interesting twist that I believe answers a lot of people's questions that answers a question. I've had myself Basically the question is that this is specifically for non North American firewall players So you may know if you're not a North American player that if you pre-ordered firewall you never got your double XP boost I never got us No, Europeans got I don't think Australians got it just North Americans got us as far as I can tell maybe maybe South Americans too I don't know so They've talked in the past about how they're trying to make that rise how they're trying to work with Sony to get Get you know get it sorted so that we can get our double XP boost But then I saw this reply.  I'll pull it up on the screen now so you guys can see so They're applying to someone who was a complaining that they didn't get the The XP boost and their reply was hey bud They were overloaded with messages around launch and I didn't hop on until a week or so afterwards We feel terrible about EU players not getting double XP But we have something special planned. We hope will make up for us. So this is kind of interesting If you look at the wording of this it makes me wonder Does that mean we won't get XP and we'll be getting something else instead because It's like something special plan to make up for it could be like a double XP weekend Maybe would that be something that would make up for us. Could it be some kind of exclusive Isom? Just for the Europeans or something like that or but you couldn't really exclude Americans then, you know, so it's it's kind of like I Don't know. I want to know what you guys think that could be Maybe it is just that they will give us the double XP at some point But at this point now it's been over a month I know some people European people already have hit like level 50 So double XP wouldn't really do them any good at this point I know it's not a huge thing But it is something that we were advertised and that we paid for kind of when we pre-ordered. So, yeah That's just a quick update on the EU XP well not even just EU. I know they singled out EU there and that tweets But I'm pretty sure it applies to everywhere. That's not America. So, yeah With that I will end this video just a little little Off the cuff as you can tell by the way, I'm like I can't really talk properly. I don't have a script I'm just going off the cuff here and with that I will end the video before it gets worse Thank you for watching. Please consider doing all the usual shies and I'll see you guys in the next one. Bye. Bye Stop recording


Good afternoon everybody and welcome to 20s annual Toronto Perioperative TE symposium. I want to thank organizing committee for inviting me for this symposium. I'm going to talk about common errors, lessons from three years of Perioperative TE QI review at Toronto General Hospital. The objectives of this talk is describe and illustrate common pitfalls identified during QI review of Preoperative TE studies at Toronto General Hospital, describe the extent to which studies depart in clearly significant ways from current guidelines, and describe the challenges of maintaining an ongoing QI program and potential approaches. In this guideline, I'm using couple of in this lectures. I am using couple of guidelines and we have to use this guideline always in our daily work. The most important one is this guideline that was published in 2020 by American Society of Echo and Society of Cardiac Anesthesia, the guideline for the use of TE to assist with surgical decision-making in the operating room. Because that guideline did not talk about adult congenital heart disease, we should use this guideline as well that was published 2019 about Comprehensive TE for children with congenital disease and adult congenital disease. Because we are doing like about a hundred case of adult congenital heart disease operation per year in Toronto General Hospital. So we have to take care of these patients in the war as well. And of course the latest guideline of American College of Cardiology and American Heart Association was published in 2021 about Management of Patients with Valois Heart Disease. In the program that I am doing now this last almost three years from April 2019 to October 2021, this time we had about 2,400 intraoperative TE in Toronto General Hospital. Of course, I cannot review all of them, but I review 290 of them. It means only 12 percent. From this 290, 2 of them were Valois Heart Disease. So because that's the area that we need more decision-making and we need more detailed echo. 119 of these cases, that's a surprise. It means 59 percent of all Valois Heart Disease that I reviewed, they didn't have any echo in the Toronto General Hospital. Some of them they had the echo outside, that we can have access by single external, their image. And many of them we have only report. There is no image available. So when we go to the operating room, the team of intraoptee has to start to do echo without any previous images. So it's not easy to do a complete echo in 10-15 minutes and share in decision-making. Also, surgeon himself or herself knows the patient very well. Out of 290 cases, 19 patients, 6% of them had a second poem run. And 2 of them had a third poem run in the war because of TE finding post-stop. So TE is not only important in pre-op decision-making, but is more important in post-stop decision-making about the completeness of the surgery that we did for the patient. This is a breakdown of 290 cases. As you see, the most of them are valve replacement, adult congenital disease, valve repair, and different type of surgery. It doesn't mean that, for example, the number of the valve repair that we do in 2-3 years is only 55. 55 was reviewed by me. So it was more than this. We are doing like 100 mito valve repair per year in Toronto General Hospital. What domain I have looked at in that program for these 290 cases, I used some of my old experience in accreditation in Serbia, Arabia. And I used this paper from European Institute of Cardiology about the training of Team 4TE. And especially this paper, very nice paper from Sunnybrook University in New York. And this is probably the only paper that did a very systematic way, the QI of their program. Also, the program is not a very big program. So they looked at in that paper from New York four domains. Image acquisition, completeness of their study, image interpretation, and completeness of the report. And in my assessment, I broke down this one to 2-part image interpretation pre-op, image interpretation post-op. So it will be the 5 domains that I have looked at. I give you a case example. 55-year-old man was referred to our center for mito valve repair. And as you see, the first image, it shows the flail posterior leaflet. Also gain is too much. We like to have a good ECG, but many times it's not possible in the world. And this is a severe MR, as you see, anteriorly directed. This is 3D of this pre-op study. You see there is a flail P3. So we have to show this to the surgeon before he or she started the surgery.  This is a post-op study, immediate post-op. You see a flash of color here. That flash of color is anteriorly systolic. And usually when you track it, go a little bit, mid systolic will disappear. After 5, 10 minutes, this will disappear. So this will not be assumed as a residual MR. You see here there's no flash of color anymore. And the mean gradient, we always check it, because we don't like to have MS after the repair, and always use the dense part of the Doppler, not the less dense part. And there's a couple of paper that we use, we should use the dense part. And this less dense part is because of the pressure recovery effect or Doppler effect. There's lots of debate about why we have this one. But we see it many times after mitovav repair or mitovav replacement. So we use only the dense part. This is a type of the report that I generated for this special case, case number 264. And you see it with more detail here. We use the five domain. And this five domain, for each of them, I gave them a score of total 10. This special patient for image acquisition, this study took 10 out of 10, completely so it's 10 out of 10. For pre-op interpretation, 8 out of 10, post up 10 out of 10, and completely report 10 of them. So five domains, I have looked at it, and I gave to this staff a score of 48 out of 50. It's a very good score. But I will not send this score to them during the report. I will keep it myself. This is how I describe it. I go to the history of the patient at first a little bit. What was the pre-op finding? It means I will re-report that study. And I will emphasize to the part that are important, surgical procedure, what was done, because most of the time I've watched the surgery as well. So there was a magic stitch between P3 and the commissioner to solve that MR. And in post-op, there was no SAM. So what we should emphasize in the post-op study, for example, I wrote it here, and I gave an image number that if they want to go back and look at it again. And how was the final report? This is the magic stitch or corporate here. And always in my QI report, I have a part that is an educational comment, and this educational comment is related to that special study. And I always use the latest paper published about that part. That's the reason that I have to review the papers very well myself. So pre-discharge, transtrosy, how was? I look at it always, pre-discharge, echo of that patient. That's the reason that I do the review one week after that surgery to have the post-op transtrosy as well. And I do my conclusion. I will send this report, return report to the staff and the fellows, and I see it to the director of a PEG program that is Annette. And this QI report qualifies for Royal College CME as well. So most of our staff are using and I use it myself. The question that should be answered, do we expect the quality of the echo be exactly like a quality of the echo that cardiologists are doing in the echo lab? For sure, no, because we don't have enough time in the war. And the training of our team is different from cardiologists. I am cardiologist myself. And has there been any improvement of tea quality during this program, these two or three years? Yeah, I see the constant improvement. And many times I am inside the war as well, watching the tea that the staff are doing. So what time our staff do the best? What part? Probably the completeness of the study. The study are very complete, started from IVC going to the Ayurvedic arch at the end. So our very complete study, compared to the study that we as a cardiologist, we do it, we do tea mainly a goal oriented study. The part that is not very good is image acquisition. And the reason is clear because our fellow are the first operators, some of them are new, their study quality will be much, much better at the end of the fellowship. But at the beginning, sometimes it's not very good. But we have to deal with this. And the improvement should be mainly an image interpretation and completeness of the report. And we should supervise the fellows more when they generate the report. Let me show you a couple of examples that there were error, challenge, and pitfalls. The case number one was a 24 year old man with a known history of unicast with the aortic valve and had a biopsygic aortic valve replacement. You might ask me why 24 year old has a biopsygic valve? That was the wish of the patient himself. And immediate post-op tea, you see this AI. So always the question is, is this AI valvular or paravalvular? We use explain to show it, this explain, you see the swing ring here, you see the AI is coming from inside the swing ring to jets. So it's a transvalvular that is a very common finding in the magna valve. You see the 3D of this. And as you see in the predisposition, it's still I believe that AI is there or two jets as we saw it in the war. But if you follow this patient, this AI will disappear. Eight months later, you see the valve, and you see that AI is not there or very, very trace. This is a very nice paper about transvalvular or pre-transprosthetic AI in a magna valve in the war. They describe it why we have it in this paper that was about 700 patient. They believe the cause of that is this fabric between the ring and the strut. This fabric, it will leak. Most of the time, it will close after protamine, but some of them will stay and will be closed in couple of months. This is the design of this valve, Hancock is a pulsing valve, doesn't have usually commercial leak, but magna valve and Avalus valve, they have a leak, magna is more Avalus has it as well. Case number 268, you're old man, excuse me, refer to our hospital for AVR, interop T was done. This is pre-op, you see the patient has AS and mild AI, calcific AOT valve. And this patient had a magna again, AVR. Immediate post-op, you see a turbulence at the LVOT and you see some AI, more close, that's a transvalver AI. Here you see, like previous case, the AR is transvalver, but it's too much. It's not mild, it's like a moderate or moderate to severe. That's a trans-gastric view, you see the valve has a turbulence and has lots of AI. And this is the gradient across the valve, very high gradient, and you see this dense part that because of the flow of the AI, is a high as well. So this patient has a almost severe AS and moderate to severe AR. Should we accept the result? Of course no, but this result was accepted, was discussed with the surgeon and the team accepted and the patient was transferred to the ICU, was extubated at first and then re-intubated a couple of hours later, was a hypoxic and was not doing fine. On day three had another TE and this severe AI was shown much, much better than interop and patient had to come back to the ward on day three. So the cause for that AI it was not just a simple commissure AI, the cause was when the surgeon did a root enlargement during the closure of this patch, the surgeon interrupts the leaflet of the biopasic valve as well. So that was the cause of the AI and was redo again another valve and it was okay. The case 355, an old woman had bicuspid AVR due to severe AS. Immediately post up, beside the valve always look at the LV and RV function. Here RV is very good and after couple of minutes RV deteriorated quickly and this was picked very well by our fellow Rebecca and she told the surgeon RV is not doing fine. He is down severely so surgeon decided to go back and do the bypass of the right corner.  So this was a very good pickup beside the check for valve always check RV and LV function. Case number 4, 71 year old man had a biopasic AVR due to bicuspid AVR severe AS, trivial AR and post up we saw this little tissue moving here and we saw this is a good AI. So we told the surgeon probably the leaflet of this new AVR is turned so and the AI is too much. So he went back and again here shows that the AI is coming from the area of the left main but still we saw that the AI is because of the turn leaflet surgeon went back couldn't find any turn leaflet took that small tissue out came off and again was the same AI he said it's not okay he went back again and check the valve and this time he found the hole above the valve there was a hole just below the left main coronary artery that was communicating between aortic root and the LV and acting like AI. So this was a eutrogenic hole he closed the hole but still at the end we had this AI here is now more clear this is trans-gasic this AI is outside the ring because there is a communication between here that is a left main below the left main to the LV and so the result was not good this patient develops this simulator and pass the replacing 59 year old woman under one biopsyc MVR in our center you see in the post-stop this is a MVR a small flow is here and the team accepted this and so this is just a small part of our leak year later the patient came back with fatigue and when they did the trans-gasic echo they saw the lateral wall and on the wall is hypo and they did in the echo lab they found this leak is much much more than before and it's a continuous it's not part of our MVR that is systolic this is continuous flow this is a very nice sweep of that flow you see the flow is from circumflex and going to the LA so this was a damage of the circumflex that was not picked up in the war so this is a year after you see again a nice sweep shows the flow continuous flow from circumflex to the LA a damage to the circumflex during my toe valve repair or replacement happens it's not common it's about less than one person and this is the only case that we had during that last three years this couple of paper about the damaging of circumflex during the my toe valve repair or replacement in summary comprehensive approach to the qi in perioperative tea can improve the quality of the studies performed by the perioperative tea team it is very important to perform a complete exam in a systemic manner for all patients whenever is possible interoperative echocardiography should be an integral and active part of the heart team for decision making clear communication and having a common language with the surgical team are crucial to overcome the challenges and possible complications that may occur in the course of the surgery ideally more studies should be reviewed by the qi program however the main challenge is the time limit as each case review takes between two to three hours in order to be significant scientifically grounded comprehensive and educational for the related staff and fellows and of course we need always the feedback from the staff cardiac anesthetist in the war that I send the case for them thank you very much


It's just Anna and I today on this Friday and Anna, we are going to be talking about something that so many are plagued by that is really running rampant. It's really an epidemic that's happening in our culture and in so many believers today. Yeah, absolutely. Well, coming up on today's program, we have. Have you ever struggled with feelings of fear, anxiety and guilt? We don't want you to struggle with it. It's the weekend. It's time to be free. Well, these thoughts can be debilitating and can even prevent us from fully walking in the freedom that God desires for our lives. Tom had the chance to speak with Bishop Mark Stephen Filkey and he addresses the widespread prevalence of anxiety and fear in our society as well as offers advice for overcoming fear so you can take back your life. It's a great conversation that you're not going to want to miss. So coming up in just a moment. Yeah, so fear and anxiety can really like like I was driving to work today feeling so happy like the sun is shining. The birds are chirping and very light hearted. But when we are gripped in that fear, it is like this bondage that just wraps itself around us and suddenly like all the goodness seems to go away. You know, a lot of us, I think we've had moments that are times where we've wrestled with fear and anxiety at one point and other. But one thing we have to remember is fear is a spirit and that we have to use those weapons of the war. We have to use the word of God to just come against those things. And so today, if you're wrestling with so many things, I know so many people are dealing with fear, anxiety, depression, all of these things as we see what's happening in our world. If you look at the headlines, things continue to unravel. But we know that there is hope in Jesus. So we hope today that as you're watching that you would be encouraged, that you'd be strengthened and that you would have strategies to overcome anxiety. And right now we're going to go to Tom's conversation with Bishop Mark Steven Filkey as they discuss how we can leave fear behind. Take a look. Fear and anxiety are tactics that the enemy uses to draw us away from God and the good plans that he has for our lives. And it's only when we choose to live by faith and not by fear that we can begin to truly flourish. And you know, Bishop Mark Steven Filkey is our next guest. And in his book, Fear Must Not Win, he offers a deep understanding of fear and how to overcome it with God's strength. Mark, thank you so much for being with us today. Thank you, Tom. Greetings from the left coast here on the west coast here in California. You know, it's a different planet than where you guys are, as you well know. Yes, you know, enjoyable. When I visited out there as a tourist, I'm sure living there, it was a little bit different, but I'm sure there's a lot a lot of great, exciting parts of seeing God move out there in California as well. Yes, God is moving and it is. You're right. In terms of geography, it's beautiful. But I want to tell you, we've we've got the devil on the run.  This is in many ways, it's kind of point center for all the demonic activity that you see happening, you know, in Hollywood and different places that's between Hollywood and San Francisco. But you know, thank God, that's one of the reasons I wrote the book, you know, because we're right here in the middle of a spiritual war zone, I felt like that I needed to address the subject 45 years of experience of teaching people how to overcome fear, panic attacks, phobias, and all of those things through the presence of God and through the word of God. And so I'm so excited today to be with you. I was hoping I'd get a chance to sit down and talk with you, Tom, and praise God. God answered my prayers. Well, hey, thank you. I'm so glad that we're able to have this conversation. And let's talk about that. Let's talk about that thing of fear, you know, where the enemy comes in like a flood, God raises up a standard, doesn't he? And so we see that Christians, in many cases, struggling with fear of different kinds. Let me ask you from your own childhood. How did God, you know, begin to develop your victory over fear? In fact, I have to tell you, you got to tell the hash brown story if we have time here, because it's a great story. I would love to.  If you think back, if you think back into your childhood or back in your adolescence, many of our deeply rooted fears, and I'm not talking about God given natural carefulness, God given fear, which keeps us from, you know, running into traffic and picking up rattlesnakes. But the type of fear that troubles us, a lot of it is sometimes, or in many instances, rooted back into our childhood. In my own case, and I'll try to make this brief, my mother and father were both pastors. My mother was a fiery evangelist. My dad was a pastor, a loving pastor, and they were great people. But what a lot of folks did not know publicly is that my mother struggled with she was bipolar. And so one day she would be up and the next day when she went down, she would bottom out.  And grant now mind you, my mom and dad are already moving they're not pastoring, but they're moving into ministry at this point. They're they're believers, they're born again, believers. But my mother was secretly struggling with her own fears, deep anxiety, deep emotional sadness, panic. It's a long, long story. And a lot of it's in the book. And I would invite our readers to get it and to really, I mean, our listeners to really get into it and read it because it will help you.  I love your dad, but we're not going to be here anymore. We're moving to New York. And you maybe, you know, she was using me to channel her fear and her anxiety. And what she did not realize is that she was actually at the time, unknowingly, passing down a generational curse.  And later, of course, she eventually got delivered, became a her and my dad became members of our church. But those early years were so filled with so much drama. And so many highs and lows that it affected me where it I didn't realize that but as I got into my teen years, I was so affected by it that I had abandonment type of issues afraid that I would be abandoned. I had moments where I'd wake up night terrors, you know, panic attacks. And I was just in my late teens and it followed me, you know, into a moment where I had a divine encounter with the Holy Spirit in Los Angeles. I was almost 18 years old. It wasn't a church. It was sitting on a curb. And the Holy Spirit came to me sitting on that curb. I was weeping, crying. I was having thoughts that my life was not worth living. I couldn't understand why I had lived and gone through what had gone through with with my parents and my family. And I remember the peace that I felt when I the presence of God came to me sitting on that curb in Belflower, California, all by myself and hearing the Lord say, Mark, you're not alone. I'll never leave you. I'll never forsake you. And here's what he said to me. He said, you don't have to be afraid because I am with you.  And it changed my life. And after that experience, God spoke to me. I came back here to Northern California and put together what was a Christian band back during the Jesus movement. You know, there's a movie coming out about that. I know you heard about that. And during the Jesus movement and God spoke to me and I put a nine piece band together. I play a number of instruments, 19 if you count the kazoo and the tambourine and put a band together and we went down into the tenderloin, which is the worst part of San Francisco. And we began to hold revivals. And it was there that I began to use my gifts to begin to deliver people from their fear and their anxiety. And hundreds of people, I would say thousands of people were saved in the tenderloin on the street. I mean, we would set up our instruments, Tom, down in the streets. And we would begin to sing the old Andre Crouch. I was later blessed to call Andre my friend. But in those days, I didn't know I'm just new to songs. And we would go down and we would sing and we would we would just begin to worship and prostitutes and drug addicts and pimps. And people who were demon possessed people who were a trap that alternate lifestyles would come by the dozens.  So that's what really started my journey years and years ago of helping people get delivered of something that the enemy had meant for my life forever. You know, God set me free. And I'm not I'm not going to tell you that I didn't have issues afterwards, because even into my marriage years, I continued to realize that I had to stay in the word to stay free from all of that fear and that anxiety, you know, well, I do. And I can identify with your story because I remember doing ministry in New York in the first time, having tremendous fear, intimidation, going into Brooklyn, going into the difficult areas. And but then seeing by the end of the evening, seeing people coming to the Lord, the devil run in the other way. I love that. I love that. And so let me ask you about so we we see different, different things that are sources of fear in our life. And I know you can list them in the book. How is someone going to access the victory that you've had that I've had over fear other people that haven't experienced that? How do they begin to access that victory? Well, you know, I think, you know, if we can just regress for one second, I think it's really important and I cover this in my book. I mean, I take there's a couple of three chapters where I literally use every word to expose to do an expose on the powers of darkness and how they were how they're using media and social media and using, you know, news network, secular news network. That's why Tom, the cornerstone network is so powerful and why why it's so important because you are the front line. I mean, this is the front line that's facing off with the evil that is flooding, not just into living rooms. Remember, Tom, when you and I were growing up, I don't know how old you are, but I bet you can remember when we only had three channels. I can. It's hard to believe that that kind of a country ever existed. But yes, I do remember. So so three channels. And if you remember, they came on it's like five or six a.m. And then at nighttime, they would say, this is the end of the broadcast day. We say, God bless you.  And that was the end of the broadcast day. And they may have dedicated an hour or two maybe on reporting the news. Today, there are thousands of channels. And I want you to listen to the language, Tom, channels, you know, the word channel is the same word that they use for like channeling spirits. If you think about it, it's the same terminology. But now there are thousands of channels. We have the enter net. A net is something that catches people. You have the World Wide Web. That's something people get caught up in. So we have these thousands of channels in which the enemy, the powers of darkness, I believe there's millions of demons that are traversing through these talking points. What I call sock puppets or talking heads, demonic talking heads, that's repeating demonic talking points that's trying to incite fear, to incite division and listen, wouldn't it be wonderful if the only people that were affected by that was the secular world? The problem is Christian people watch those type of programs too. And so even children, if you look at these teenagers, we see these teenagers and see all of our youth today. Every time you see someone with they have a smart device, earphones, it is nonstop dispelling with fear, story after story. And Tom, you know this news network do not make their money by spreading peace. They make billions of dollars by inciting fear, frustration, panic. There is a story, as you know, every 15 minutes, there's another 15 minute cycle and they'll run it over and over and over again. Well, as a result, many of our listeners, you may not even know why you're feeling what you're feeling, but I want to tell you there is a spirit in this. We have to recognize that the Bible says that Satan, he is the ruler of this world and he's the prince of the air of this world. And as a result, he is using the frequencies of this. I tell people, you know, Satan is licensed to use the lower frequencies. Tom, what you're doing today is the higher, that's the higher frequencies. Born again, believers, we operate in the higher frequencies of the Holy Spirit. The devil is so irritated because he cannot interrupt what we get through the presence of God. But what he does do is he incites fear and panic and phobias and all of this stuff through the networks, as well as just life, you know, around us. So as a result, you know, I don't want to give too much away, but in the book is 211 pages of pure information and power and revelation on how you can secure peace through a personal relationship with the Lord Jesus Christ. I'm not talking about a casual touch and go, but I'm talking about an unceasing prayer life, plugging in, connecting. You know, we're seeing revivals right now, Tom. I don't know if you've seen some of the revivals that are breaking out right now with Asbury and all of the different colleges. It's only one of many. I don't know if you've seen it, but the last couple of weeks, really the last couple of three weeks, there's revivals breaking out all over America, which I've been prophesying revivals upon us. But in the midst of that, there was a warfare that is going on between the powers of good and evil over the souls of believers. And if I can, I'd like to address all of all of our viewers today, and I want to say to you that if you were bound by a spirit of fear, if you find yourself losing sleep, you're suffering because you can't sleep at night time.  You find yourself going to the day with non non stop thoughts of worrying about the future.  God is a deliverer. You know, Tom, we're seeing people all over America delivered a fear right now. In fact, we're having meetings. I'm calling all of our calling all of our meetings fear free meetings. And we have a whole fear free tribe, a fear free nation that's rising up that is saying no longer will we be afraid? And I think what our viewers need to understand today, Tom, is that there is power in peace and the devil knows it. Yeah. And so to answer your question at the very root, in order to really get the peace and to be delivered a fear, there it's really it's in the power of relationship. I'm not talking about going to church once a week, but I'm talking about that unbroken that connectivity with the Holy Spirit. So you're listening to him all day long, every day, every moment of every day. You know, it's not it's more than a midnight prayer. It's more than just saying a prayer in the morning, but it's an unceasing relationship with the Holy Spirit. And I teach people how to do that in this book. I teach them how to be delivered of every type of ungodly, irrational fear that comes out of the imagination. And I am so thankful today, Tom, that we do not have to live in a state of panic. And I don't know what it's like where you are, but everywhere I go here, I'm talking, I talked to a waitress the day before yesterday and just started ministering to her. And she sat down and just began to weep. She said, I don't know how you, how you knew that I had been suffering with such fear. And I began to share with her that she wasn't alone. There's people all over America that are privately struggling with this irrational, panic, phobia, can't sleep at night time. That is not God's will for our life. Amen. Absolutely. I don't mean to preach. I don't mean to preach, Tom. Sorry. That's all right. No, that's some good preaching, especially like how you bring out that this is done through relationship, through relationship with Jesus Christ, real relationship, moment by moment relationship. Mark, again, the book is called Fear Must Not Win, Finding Peace, Confidence, and Courage in Challenging Times. Thank you so much, Mark, Steven Filkey for being with us. Mark, it's been great. I appreciate that. Yes, sir. I'm sorry I didn't get to the hash brown story, but it's in the book. It'll bless you. It's in the book. I'll have to get the book. It's a great story. Thank you so much, Mark. God bless. God bless you. Bye-bye. Cornerstone Television has believed in the power prayer sits in Synception 44 years ago. We invest heavily in our prayer line to provide you with 24-7 personal prayer, knowing it brings breakthrough, healing, and wisdom. Last year alone, we received over 65,000 prayer calls. And if you had partnered with us, thank you so very much. And when you give this month, I am so excited to share with you my new book, Praying on Another Level. It's a 30-day journal to take your prayer life to a new dimension in God. You see prayer as how we separate good ideas from God ideas. It's how we unlock the door to revelation. And it's where we get our strength to build up our spirit man to hear from God throughout our day. All that and so much more. So call us now at<PHONE_NUMBER> or give at ctvn.org forward slash donate to request your copy. It is time to take your prayer life to another level. We're so glad you're joining us this Friday on Hope Today and we are called Hope Today because it is our heart to bring hope into those places where you might feel hopeless. And as you heard the conversation all about fear. So often fear can keep us in this place of hopelessness. Like there's so much ahead. There's so much you want to experience in life and yet fear is gripping you and it's keeping you held down and you know Sydney and I were just kind of chatting like there's just so many layers to the conversation of fear and so like over these next few minutes of ministry time we're just we just kind of want to unpack some of our thoughts and experiences and hope that you can get on the other side because Sydney and I have certainly had struggles with fear and the anxiety and we're living in some freedom today. We surely are and so I know a lot of people have something they're dealing with and sometimes it's hard to admit but we just want to let you know. This is Anne was saying Hope Today as we're all about encouraging you, lifting you up and one of the things that I know Anne and I were very big on is like not only is it just like being in the presence of God, being in your word, listening to the Holy Spirit, but we are you know here at Hope Today. We're really big on if you need extra help, if you need to go to therapy, if you need to go to counseling, if you need to seek people then one thing I have seen even in the midst of my own life when I'm walking through hard times or walking through maybe a season of depression or grief. It's when I have therapists, when I have my community and people around me to lift me up to speak life into me. We are not meant to do life alone. So if you're battling with fear and you're seeing things and you know that is going on is that it's so important that you have community. You know one thing and I've been thinking about it's not just God. It's God, Jesus and the Holy Spirit. They have the three of them are all together, you know, leaning on one another. And so that is our model. That is our archetype. How much more so should that be, you know, modeled in our lives? Right, absolutely. I mean, God made us for relationship, relationship with himself first because he is our source of life. But then relationship with a body of Christ who are your brothers and sisters that you'll meet in church that you might meet in your community everywhere you go. There are believers in Christ that want to wrap their arms around you. And when fear is speaking louder than truth, yes, God, the Holy Spirit through the power of the word can speak truth into your heart.  You know, here on Hope Today, we do love to bring you scripture because we know that God is the first source. And today our focus scripture is Psalm 121, 1 and 2. We love this verse. It says, I lift up my eyes to the mountains. Where does my help come from? My help comes from the Lord, the maker of heaven and earth.  There are so many different circumstances that can trigger that fear. You know, as Mark shared, it came from childhood trauma. We can go through devastating experiences, adults that bring that gripping fear into our lives. Or sometimes it is just something you can't quite tell where the root of it is, but it is the enemy coming after you. And the Lord is our helper. He is the one that wants to deliver us because he has given us a spirit of power, love and sound mind. You know, and as you were speaking, one thing God was just dropping in my spirit is isolation. That's one thing when it happens to fear when you're going through a tough time that you will self isolate, that you will go to corner, that you don't pick up the phone, you don't want to talk to anyone.  I just feel that strongly in my spirit that today is the day that you need to reach out.  Nobody cares about you. Nobody's thinking about you. You have all these fears that are going on. But those are the moments where it takes the biggest courage is to reach out for help. And in those moments it could be just crying out to God and just saying, like, God, I need help. I am desperate. I don't know what's going on. But also the other step is give someone a call because we are here for you. And maybe that's you today that you are in a place of just isolation, that you see so many things that are going on and you just feel like in a tiffy and you just don't know and understand what's going to happen next. But give us a call at our prayer line at<PHONE_NUMBER> because one thing that we are here for at Cornerstone Intelligence Network that brings you hope today, whether you're in Pittsburgh, if you're in Florida, Alabama, if you're watching anywhere around the world, is that we are here for you 24-7. And we believe in the power of prayer. We know that when two or three are gathered that He is in the midst. And so let us today join an agreement with you and believe those bondages, those things that are over, you're going to be broken off in the name of Jesus, all the fear, the torment, the depression, all of that. There is power in the name of Jesus. There's power in the blood of Jesus. And we want you to experience that wholeness and that freedom today. Yeah, and here's the good news. It truly is possible to be free from fear. Whenever you get help from the Lord, when you get help from community or a therapy, you are given tools that you can put into practice like starting today to be able to set you free. The Bible also says to be transformed by the renewing of your mind. So one thing that worked well for me is that I would put scripture in front of me everywhere in my house, in my car, and I would speak it out loud. I would pray it over my life until I could live out that courage that God put inside of me because He has so many big plans for you and me. And so today as we're drawing to a close and we're about to head into the weekend that we just want to offer and let you know that Mark's book, if you're in may not win, that if you have any amount that you give to our ministry, we would love to put that in your hands today.  We know that we don't wrestle against flesh and blood, that there's all these things that are coming at us, but it is such a joy and an honor and a privilege for us to come into your home to speak the truth and the love of Jesus. And we know that is the greatest hope that we have. And so as you start your weekend, we want you to hold on to that, know that you are valued, know that you're loved and we'll see you next time.