Question: if the lower chamber in the heart needed fixed would you have to replace the whole heart or just the lower chamber

Samuel Vennin answered on 14 Jun 2018:

It depends on the disease. Replacing the whole heart as you say would only be done as a last resort. There are some conditions where the lower chamber is too big (dilated cardiomyopathy) or too small (hypertrophied cardiomyopathy). For these, we would first treat them by prescribing medicine to control blood pressure and abnormal beating of the heart, and sometimes even implant a pacemaker to improve the heart’s pumping ability.
Another way to deal with this situation is to “rewire” the arteries connected to the heart. The heart is normally formed of two pumps that eject blood in two arteries: one that send blood full of oxygen to the muscles that need this oxygen, one that send the blood emptied of oxygen to the lungs where it gets replenished in oxygen. It happens in some very rare cases that there are no separation between those two pumps and the two types of blood (full and empty of oxygen) are mixed. Instead of creating a separation between the two pumps which would be very hard to do and risky to the patient, we just “unbranch” one of the two arteries (the pulmonary one) and branch it to the upper chamber (the right atrium). This is called the Fontan procedure and the video below explains it:

As you see, when one of the chambers has problems, we first try non dangerous methods to fix it and will only try to replace the whole heart once everything else has failed because it is a very complicated operation to perform and we need to wait for a heart to be available.