Coronary Artery Bypass Graft (CABG)

Coronary Artery Bypass Graft or CABG is a surgical procedure used to treat coronary heart disease. It aims to improve blood flow to the heart muscle. In CABG, a healthy artery or vein from the body is connected or grafted to the blocked coronary artery. This allows the blood to bypass the blocked portion of the coronary artery and reach the heart muscle.

The key steps in CABG are:

A chest incision down the middle of the breastbone to access the heart.
The heart is stopped using a cardioplegia solution and the body is placed on cardiopulmonary bypass. This allows the surgeon to operate on a still heart.
Healthy arteries or veins are taken from the chest, leg or arm and grafted to the blocked coronary arteries beyond the blockage. The most common grafts used are the left internal mammary artery and the saphenous vein from the leg.
The grafts are then attached to the coronary arteries, routing the blood flow around the blockage to the heart muscle.
The heart is restarted and the patient is taken off cardiopulmonary bypass.
The chest incision is closed with sutures or wires.

The key benefits of CABG are:

Improved blood flow and oxygen supply to the heart muscle.
Potentially fewer angina symptoms and reduced risk of heart attack.
Improved ability to be physically active and reduced heart disease progression.
Potentially longer survival and life expectancy.

The risks of CABG include infection, blood clots, heart attack, stroke, irregular heart rhythms, and memory loss. The success and longevity of CABG depends on the patient's overall health, graft patency and progression of coronary artery disease. Lifestyle changes and medications are still often needed post CABG for best outcomes.

Topic Highlights:-

Coronary artery bypass graft or CABG surgery is the recommended mode of treatment for patients with severe narrowing or blockage in their coronary arteries.
The procedure involves creating new routes for normal blood flow around the blocked arteries.
New routes are created using arteries or veins from other parts of the body, such as the leg, arm or thorax.
This presentation provides information on the process involved in CABG, its types, and guidelines on managing angina.

Transcript:-
The most widely used invasive treatment to treat angina or coronary artery disease is percutaneous coronary intervention (PCI), also called percutaneous transluminal coronary angioplasty (PTCA), and coronary artery bypass graft (CABG) surgery.

In CABG the surgeon will bypass the blockage using grafts. One end of the graft is attached to the aorta and the other to the coronary artery beyond the blockage. The surgery is done using many methods.

In the traditional form of bypass surgery, the surgeon makes a vertical incision on the chest to expose it. The breastbone is cut using an electric saw. The heart can be seen beating in the chest. During the surgery the heart is cooled and stopped so that the surgeon can perform the surgery easily. The oxygen requirement of the heart decreases during this period. The function of the heart and lungs is taken over by a heart lung bypass machine. This machine is controlled by a technician, the perfusionist.

Simultaneously, depending upon the number of bypass grafts needed, another surgeon will dissect and remove the vein from the leg, arm or the thorax. This process is called harvesting. The graft taken from the leg is of the saphenous vein. The arterial grafts are from the forearm called the radial or ulnar artery. The veins or arteries for grafting can also be harvested endoscopically, where a small incision is made to remove the vein or artery for grafting. Many times an artery from the chest wall is also used, called the internal mammary artery.

One end of the graft is stitched to the largest artery arising from the heart, called the aorta, and the other end is stitched beyond the blockage on the coronary artery, thus creating a new channel for the blood flow. After the surgery is completed, the bypass machine is slowly switched off and the heart is restarted using drugs and electric shock. The chest wall is then closed. The patient is then shifted to the intensive cardiac care unit for further management.

CABG is also performed using advanced techniques like minimally invasive surgery. Here the surgery is done through smaller incisions. This surgery is suitable for patients requiring 1-2 bypasses in the arteries on the front of the heart.

In some of cases an advanced technique called beating heart or off-pump surgery is performed. It is performed using a stabilizing device to restrict the movement of small segments of the heart while the patient’s heart continues to beat. This allows the surgeon to operate without the use of the heart lung machine used in conventional cardiac surgeries.

Some changes in lifestyle can help manage angina. It is important to exercise regularly. Have regular check-ups with the doctor for blood pressure and for complications of hypertension. Manage stress levels effectively and take prescribed medications regularly.