Researchers have found that although bypass surgery of the heart saves many lives, it is also linked with some significant risk factors, including loss in mental ability of the patient.
A study conducted concludes that approximately 50% of the patients studied showed a decline in concentration, short-term memory, attention span etc. 5 years after undergoing a heart bypass operation. This decline in the mental ability has been contributed to the use of a heart-lung machine during the surgery.
As we know, during the bypass operation the surgeon takes a blood vessel from another part of the body (usually a vein from the leg) and attaches one end to the aorta and the other end to the coronary artery just below the blocked area, so that the blockage is bypassed and a normal blood flow is maintained. Traditionally, the heart is stopped during the surgery and its activity is taken up by the heart-lung machine (which supplies the body with blood and oxygen during the procedure).
However, researchers have linked the use of this machine to some serious complications. According to them, because the blood flows through plastic tubing it may trigger an inflammatory process that may damage multiple organs. It can also cause formation of tiny bubbles, which may travel through the blood to the brain causing a decline in mental function. Studies have also found that patients who remain on the heart lung machine may have increased risk of developing late complications such as bleeding or long hospital stays.
But researchers say that with the advent of some new devices the heart lung machine may not be required at all. These devices help to stabilize just a small portion of heart for operating whereas the rest of the heart continues to pump. Studies have shown that performing bypass surgery on a beating heart (“Off-Pump procedure”) as compared to that on heart-lung machine (“On-Pump procedure”) can considerably reduce the chances of longer hospital stays, blood transfusion and complications such as stroke, atrial fibrillation and decline in mental function. The survival rate of the patients was also found to be better (98.2%) in patients who had undergone off-pump surgery compared to that in patients who had undergone surgery on a heart-lung machine (96.5%).
Most of the studies conducted till date have shown beneficial results from the off-pump procedure but more studies are underway to confirm these findings. Doctors believe that this procedure would prove beneficial to all, especially high risk groups such as elderly people, overweight and obese individuals, people undergoing repeated operations and those with kidney failure.
With the availability of devices (stabilizers) that keep only a small portion of the heart stable while the rest of the heart beats, many surgeons have started using the off-pump procedure. With still more supportive findings the off-pump surgery is sure to catch up and become universally acceptable.