Secret Deaths of St. Mary's.
BANFIELD: If you or especially your child might be in need of a serious operation, of course you're going to want the most skilled and experienced surgeon that you can find in a hospital with a proven track record. But the parents you're about to meet wanted those things too for their critically ill newborns in the state of Florida. Instead, though, of the facts, they got promises from a hospital and a doctor they now deeply regret having trusted. CNN's senior medical correspondent Elizabeth Cohen has a keeping them honest segment right now, an investigation, "The Secret Deaths of St. Mary's."</s>ELIZABETH COHEN, CNN SENIOR MEDICAL CORRESPONDENT (voice-over): Just weeks into life, this tiny baby Layla McCarthy, needed heart surgery. Here at St. Mary's Medical Center in West Palm Beach, Florida, Dr. Michael Black performed the delicate procedure to widen Layla's narrow aorta, a defect she'd had since birth.</s>CHRISTINE MCCARTHY, LAYLA MCCARTHY'S MOTHER: He just made it seem like he was the best person to do this.</s>MATT MCCARTHY, LAYLA MCCARTHY'S FATHER: It was a - very like, no sweat, don't worry about it. You know, it's a walk in the park.</s>COHEN: But the surgery was a disaster.</s>C. MCCARTHY: I looked at her, and her legs had started - they had stiffened up a lot and they started going in an almost table-top position.</s>COHEN: After the surgery, Layla was paralyzed. Here she is today. The McCarthy's had no idea that their daughter's tragedy had a disturbing backstory. One that no one had told them. Just three months before Layla's operation, a baby had died after heart surgery by Dr. Black. And five months before that, Alexander Gutierrez Mercado had died. And a month and a half before that, Keyari Sanders had passed away.</s>C. MCCARTHY: It's horrible that you go into a program like that and they can be dishonest with you and they don't feel the need to tell you what has happened there before.</s>COHEN: One week after the surgery that left Layla paralyzed, Amelia Campbell died after heart surgery. Then Parish Wright a few months later and Landon Summerford (ph) eight months after that. St. Mary's keeps its death rate a secret, revealing a death rate, they tell CNN, could "potentially lead to providing misleading information to consumers." But CNN has calculated a death rate based on these internal hospital reports, which include surgical caseloads. We calculate that from 2011 to 2013, the death rate for open heart surgery on children at St. Mary's Medical Center was more than three times higher than the national average. These are all parents who lost their babies after heart surgery by Dr. Black at St. Mary's. They hadn't met each other until they sat down to talk with us.</s>DANTE WRIGHT, PARISH WRIGHT'S FATHER: He really sounded like he knew what he was doing.</s>MARQUITA CAMPBELL, PARISH WRIGHT'S MOTHER: All I could do was believe in his words and it was the opposite of what he said.</s>COHEN (on camera): So your baby was transferred to a different hospital?</s>RAMONA STRACHAN, KEYARI SANDERS' MOTHER: They couldn't do anything for her. She was a vegetable. Her organs had shut down, everything.</s>COHEN: At the second hospital, did they explain what happened in the first hospital?</s>STRACHAN: The previous doctor, Dr. Michael Black, kinked (ph) her artery and that's why it wasn't getting any blood flow to the left side of her heart. NOIKA (ph)</s>CAMPBELL, AMELIA CAMPBELL'S MOTHER: This is really difficult to hear. Just to hear what other mothers went tough and that the same</s>COHEN (voice-over): St. Mary's, owned by Tenant Health Care, said CNN is wrong about the program's death rate but refuses to provide what it considers the correct death rate. The hospital and the heart surgeon, Dr. Black, rejected requests for an on camera interview, so we tracked down CEO Davide Carbone to give him a chance to explain.</s>COHEN (on camera): Hi, Mr. Carbone. It's Elizabeth Cohen at CNN. Hi, Mr. Carbone. It's Elizabeth Cohen at CNN. How are you, sir? Sir, we want to know why the - what the death rate is for your babies at the pediatric heart hospital in the - your program?</s>COHEN (voice-over): He also wouldn't answer the parents' question, why did so many babies die at