In the euro area, the capital market is much smaller, and a central bank that wished to intervene would have to purchase from the banking system the loans the latter had made to the economy, for which there is only a very limited market.
This would be a very complex undertaking, even without taking into account the institutional context which would necessarily involve intervention in 17 countries. But the ECB has taken a number of measures on this front too. Banks have for some time been able to use credit claims as collateral when obtaining funding from the ECB.