“Is Bypass Surgery best for me?”
Your Heart:
The heart is a cone shaped muscular organ which lies underneath the breast bone, more to the left side. Normal heart is about the size of your first. The function of your heart is to pump blood through about 96,000 km of blood vessels distributing blood from head to toe. Your heart beats about 60-120 per minute depending on your activities. It pumps all of your blood about 500 times a day at a rate of about 5 litres a minute.
Average heart rate is 75 beats per minute; 75 x 60 = 4500 beats per hours;
4500 x 24 = 108,000 beats per day; 108,000 x 365 = 39 million per year without a rest.
For this amazing function of the heart, it requires its own blood supply to provide energy. The blood is distributed to the heart muscles by arteries (blood vessels) called coronary arteries. The right coronary artery distributes blood to the right side of the heart while the left main coronary artery supplies the left side of the heart. The latter divides into two major branches, one supplies the front of the heart called LAD and the second branch called circumflex artery supplies the back of the heart. Thus, there are 3 major tributaries to the heart. From these arteries, branches arise like branches of a tree distributing blood to all parts of the heart.
Coronary Artery Disease (CAD):
When these arteries get blocked or narrowed, ischaemic heart disease or coronary artery disease results. This is the commonest heart disease that occurs in adults. When all 3 major coronary arteries are affected, we call the condition as three vessel disease and when two of the arteries are diseased, we call it two vessel disease and one is involved we refer to it as single vessel disease. The narrowing of the arteries is brought about by deposition of cholesterol within the wall of the arteries. The coronary artery disease manifests as angina, myocardial infarction (heart attack) or as silent heart attack.
Several alternative treatments for coronary artery disease exist. They include:
- Medical management (anti-anginal medications plus statins, antihypertensives, smoking cessation, strict blood sugar control in diabetics)
- Percutaneous coronary intervention (PCI)
- Coronary Artery Bypass Surgery (CABG).
Coronary Artery Bypass Surgery (CABG):
Both PCI and CABG are more effective than medical management at relieving symptoms (e.g. angina, dyspnoea, fatigue). Coronary artery Bypass Surgery (CABG) is superior to PCI for some patients with multivessel CAD.
Although new techniques have allowed doctors to use angioplasty and/or stenting increasingly over bypass surgery, some types of heart disease may not be effectively treated with angioplasty with or without stenting. Although the immediate risks of coronary artery bypass graft surgery are greater than those of angioplasty, long-term outcomes of CABG surgery may offer the advantages of greater durability and more complete revascularization. Generally, the greater the extent of coronary atherosclerosis, the greater the benefits of bypass surgery over angioplasty. Bypass surgery may be considered a better option for some people who have:
- Diabetes.
- Disease of the left main coronary artery.
- Multiple coronary artery disease.
- Valve disease and need surgery.
- Failed angioplasty or recurrent blockage.
When the blockage is not suitable for stenting, or disease involving long segments of artery.
- It may also be a better option when the heart has weakened heart muscle
Bypass surgery often relieves symptoms of chest pain (angina), improves exercise performance, reduces the risk of a future heart attack, and prolongs life.
People with severe coronary artery disease and impaired heart function, the risk of death from coronary artery disease is less for those who had CABG compared with those treated with medicine. Factors that affect these results include the number of coronary arteries that are diseased, the severity of the disease, location of the blockage in the coronary arteries and amount of scarring of heart muscle caused by CAD.
Coronary artery bypass graft surgery (CABG) is among the most common operations performed in the world. CABG for Atherosclerotic heart disease is one of the great successes in medicine. In USA alone in 2003, about 150,000 CABG operations were performed. The Russian cardiac surgeon, Dr. Vasilii Kolesov, performed arguably the first successful coronary artery anastomosis in 1964.
Relief of angina after revascularization, improvement in exercise tolerance and the realization of survival benefit have attended the operation since its early stages. Nowadays, with the improvement in pharmacological agents, anaesthetics, surgical techniques and perfusion techniques, the surgical risks and complications are kept to an acceptable rate when done on the proper time. CABG operative deaths have remained in the range of about 3%, increasing, if anything, over the past 15 years because of the recent selection of older patients with more severe underlying disease. In a good risk patient, the risk of operative death can be as low as less than 1%.
During bypass surgery, a blood vessel conduit that can be spared from your body is taken and used as a bridge to bypass the block in the coronary artery so that the blood to the heart muscle flows through the new pathway. This conduit may be a length of vein removed from your leg. One end of it is attached to the aorta and the other end to the diseased coronary artery just past the blocked area. Taking the vein from your leg does not cause any damage to your leg as there are a network of veins in your limbs. Mammary artery that runs under the breastbone is also a most preferred conduit as it is very durable. It is detached from the breastbone and reattached to the coronary artery just past the blocked area. Another conduit that is often used is the radial artery from your forearm. There are two arteries in the forearm named radial and ulnar arteries. Removing the radial artery does no harm to your forearm and hand as the ulnar artery alone can supply enough blood to the hand.
What to Expect After Surgery?
After surgery, there will be a short stay of 1 to 2 days in the intensive care unit (ICU). In the ICU, you will have continuous monitoring of your heart activity. Nowadays pain after CABG is easily controlled and does not bother most patients. In fact most patients tolerate the post-operative period well and often they are surprised that pain is not a major issue.
You will be prescribed aspirin or other anti platelet drug right after your surgery. Starting aspirin therapy shortly after having this procedure prevents complications that can affect the heart. Recovery includes physical therapy, respiratory therapy, occupational therapy, and diet counselling. By day 3 you will be able to ambulate. You will typically stay in the hospital from 5 to 7 days after open-chest bypass surgery. The amount of time you stay varies and will depend on your health before bypass surgery and whether complications develop from the surgery.
After you are released from the hospital, your recovery at home takes 4 to 6 weeks. Exercise and driving may be resumed after about 3 weeks. People who are able to return to work can usually do so within 1 to 2 months, depending on the type of work they do. The purpose of surgery is to get you back to your routine life rather than make you handicapped.
One must remember that bypass surgery does not cure coronary artery disease and does not affect the process of hardening and narrowing of the arteries (atherosclerosis). A person can still develop blockages in the new blood vessels that are used to bypass blocked arteries or in the original coronary arteries. Reducing risk factors and slowing the rate of atherosclerosis are vital to successful long-term results. Lowering cholesterol when it is high, quitting smoking, and controlling high blood pressure and diabetes are important in anyone who receives bypass.
Angina may return shortly after bypass surgery in about 4 out of 100 people. After 5 years, about 4 out of 100 people need another operation. After 10 years, about 12 out of 100 people need another surgery. This is due to failure of the bypass grafts or progression of disease in the coronary arteries.
Number of bypasses:
The terms single bypass, double bypass, triple bypass, quadruple bypass and quintuple bypass refer to the number of coronary arteries bypassed in the procedure. In other words, a double bypass means two coronary arteries are bypassed (e.g. the left anterior descending (LAD) coronary artery and right coronary artery (RCA)); a triple bypass means three vessels are bypassed (e.g. LAD, RCA, left circumflex artery) ; a quadruple bypass means four vessels are bypassed. The fourth artery may be a branch from the main artery, while quintuple means five. Bypass of more than four coronary arteries is uncommon.
A greater number of bypasses does not imply a person is “sicker,” nor does a lesser number imply a person is “healthier”. A person with a large amount of coronary artery disease may receive fewer bypass grafts owing to the lack of suitable “target” vessels. A coronary artery may be unsuitable for bypass grafting if it is small, less than 1 mm, heavily calcified (meaning the artery does not have a section free of disease). Similarly, a person with a single “narrowing” of the left main coronary artery may require only two bypasses to its two main branches. However, a left main lesion places a person at the highest risk for death from a cardiac cause without surgery.
The surgeon reviews the coronary angiogram prior to surgery and identifies the blockages in the coronary arteries. The surgeon will estimate the number of bypass grafts prior to surgery, but the final decision is made in the operating room upon examination of the heart.
Minimally Invasive CABG:
Alternate methods of minimally invasive coronary artery bypass surgery have been developed in recent times. Off-pump coronary artery bypass surgery (OPCAB) is a technique of performing bypass surgery without the use of cardiopulmonary bypass heart-lung machine. There is no clear advantage of one method over the other. Usually the heart surgeon will consider all the factors that will influence the surgery and choose the most appropriate method to suit the patient.
Conclusion:
Under certain conditions of coronary artery disease, bypass surgery becomes the best treatment option as it relieves symptoms of chest pain (angina), improves exercise performance, reduces the risk of a future heart attack, and prolongs life. It is the commonest form of heart surgery with minimal risks unless patient suffers from other complications. Bypass surgery does not cure coronary artery disease and does not affect the process of hardening and narrowing of the arteries. Reducing risk factors and slowing the rate of atherosclerosis are vital to successful long-term results