What is Beating Heart (or Off-pump) Bypass Operation?
Traditionally bypass operation or CABG (Coronary Artery Bypass Grafting) is done using the help of Heart Lung Bypass (CPB or Cardio-pulmonary Bypass) machine. This machine does what heart and lungs do normally in the body. It gives Oxygen to the blood, takes away Carbon-dioxide from it and pumps the blood to all parts of the body. This enables surgeon to stop the heart and make it bloodless. Complicated surgical procedures can thus be performed safely and with greater precision. However the CPB machine is not without its share of dangers. As the blood comes in contact with the tubes and the pumps of the machine, the body systems recognize it as a ‘foreign atmosphere’ and reacts to it. This reaction can create a variety of harmful effects on different organs and some of them can even be fatal.
The idea to avoid CPB machine and its ill effects during CABG led to the concept of performing the operation on beating heart. Here the operation is done while the heart is still pumping and the lungs are working. So the support of CPB machine or ‘the pump’ is not required. Hence the name ‘Off-Pump Coronary Artery Bypass or OPCAB’. It needs no great reasoning to understand that doing the same procedure when the target is in motion demands greater care, precision and skills.
This is a very technical question and one need to consider many factors before reaching a decision.
Even when OPCAB is planned for a certain patient the decision can be changed on the operating table depending on conditions unique to individual patients.
A heart suffering from critical shortage of blood supply, as in the case of many undergoing bypass, may not tolerate the long operation on beating heart.
The blood vessel needing bypass may be buried deep inside the heart muscle or its wall may be very thick and hard like stone.
These situations make the operation technically difficult and may necessitate the use of CPB machine. Needless to say, every patient is unique and there is no one treatment suiting all.