Heart Bypass Surgery

The blood supply to the cardiac muscle is through the coronary arteries. The coronary arteries are located in the anterior and posterior locations of the heart giving a branched appearance. The width of each coronary artery is 3-4 mm and it continues throughout the cardiac muscle as small branches supplying blood to the entire heart.

Heart Bypass surgery

The cardiac muscle experiences ischemia or lack of blood supply if there is an impairment in the coronary artery. The function of the coronary artery is affected due to fatty deposits or plaque. These fatty deposits block the blood supply through the coronary artery. In this situation, the patient begins to experience chest pain and discomfort. Angina can lead to cardiac arrest if not treated immediately. The coronary artery is either partially clogged or totally clogged in these conditions. One of effective ways to treat this condition is through a surgical procedure called Coronary artery bypass graft or CABG.

The bypass procedure of the heart is an intricate and meticulous procedure involving a team of cardiac surgeons, anesthetist and perfusionist. The patient is administered general anesthesia as it is an invasive procedure. The CABG can be done in two ways, the first one involves the maintenance of circulation through the heart-lung machine operated and monitored by the perfusionist during the procedure. Here, the heart is stopped for about 30 - 90 minutes. The second one is called the Beating heart surgery or Off Pump surgery, in which the procedure is done on a beating heart. This is safer for patients who are at increased risk of complications, such as those suffering vascular disease, aortic calcifications, carotid artery stenosis or breathing or kidney problems. Other procedures are minimally invasive bypass surgery and robotic-assisted bypass surgery.

The entire CABG is categorized in two phases. In the first phase, a healthy blood vessel is taken to create the bypass near the region where the coronary artery is blocked. The graft is taken either from the arm (radial artery), chest (internal mammary artery) or legs (saphenous vein). Since there are other blood vessels connecting these tissues, it is safe to use them. Depending on the location, amount and size of the blockage, the choice of substitute blood vessel is made. In the second phase, the surgeon creates the bypass route from the clogged site of the coronary artery to generate a healthy supply region for the cardiac muscle. The duration of the procedure ranges from 3-6 hours depending on the number of grafts the patient requires. Patients are transferred to critical care units after surgery and generally kept under admission for a period of six to nine days.

Postoperative care in CABG

The risk factors associated with the CABG procedure include heart rhythm problems, kidney or lung failure, chest wound infection and memory malfunction. Postoperative care plays an important role in retaining the normal function of the heart. Patients notice a swelling at the site of incision which gradually subsides after a few weeks. Postoperative experience in CABG requires rehabilitation as many patients complain of anxiety, lack of sleep and anorexia. Patients are advised to abstain from activities such as heavy lifting, driving and climbing stairs. Cardiac rehabilitation techniques aid the patients in improving their cardiac endurance levels and also creating an optimistic mind set after surgery. Medication and exercise in moderate levels subsequently improve the functionality of the heart; however patients are advised to avoid foods containing trans-fats and smoking.

Cardiac Catheterization

Cardiac catheterization is a test which is performed to obtain certain diagnostic information about the heart. Patients may require this medical therapy rather than undergo angioplasty or bypass surgery when they suffer from rare or easily controlled episodes of angina. Alternatively, cardiac catheterization is not performed in patients who have infrequent episodes of angina and in whom angina can be easily controlled. When a patient has heart failure due to suspected coronary artery disease or there is suspected coronary artery disease, cardiac catheterization is conducted. Cardiac catheterization can help:

• Measure blood pressure within heart.
  
• Know the amount of oxygen in the blood.
  
• Check the pumping ability of the heart muscle.
  
• Check blood flow through the heart after surgery.
  
• Collect blood samples from the heart.
  
• Inject dye into the coronary arteries.
  
• To provide treatment in certain types of heart conditions like congenital heart defects and how severe it is.
  
• To find out a coronary artery disease and if found to pinpoint the size and location of fat and calcium deposits that have built up in coronary artery from atherosclerosis.
  
• To determine whether the patient needs bypass surgery or angioplasty.
  
• Examine the arteries of the heart with an x-ray technique called fluoroscopy.

The patient is asked not to drink or eat anything, except a small amount of water, for at least 6 to 12 hours before the test. The patient is tested for allergy to iodine or other medications. Patients suffering from kidney disease or diabetes or bleeding disorders must keep the cardiologist informed. The cardiac catheterization test is performed in a cath lab by a cardiologist. The actual catheterization procedure takes about 15 - 30 minutes. The patient's electrocardiogram that continuously records the electrical activity of the heart is taken.

A pulse oximeter device that measures the oxygen levels of the patients' blood is monitored. An intravenous needle is inserted into the patients' vein to give fluids or medicine during the catheterization procedure. A sedative is also given through this IV line which helps the patient to relax.

Cardiac catheterization procedure involves passing a catheter, a thin flexible tube, into the right or left side of the heart. The doctor inserts this thin plastic tube into the groin - femoral artery. Other places where in the catheter may be inserted are the elbow- brachial artery or the wrist - radial artery. From there it is slowly advanced into the chambers of the heart or into the coronary arteries. The doctor watches the progress of the catheter into the heart's vessels and chambers on the imaging screen. Pressures within the heart chambers are measured and the blood and tissue samples are also removed through the catheter. A small amount of dye is also injected through the catheter into the heart chamber or into one of the coronary arteries.

Therapeutic catheterization: Certain types of heart defects can be repaired using catheterization. For instance, if the coronary arteries are blocked, the cardiologist can use a catheter, guide wire and balloon to open and improve blood flow to the heart. This is termed as percutaneous coronary intervention (PCI).

Normal result indicate that there is no significant narrowing or blockage in the coronary arteries. Abnormal results may suggest that the heart does not pump blood normally or the valves in the heart may be weak. There may be leakage between heart chambers. There is a possibility of aortic aneurysm. Some complications with cardiac catheterization include heart attack or stroke, hematoma, puncture of the heart or arrhythmia.

Angina

Angina or chest pain is a typical symptom associated with coronary artery disease. Angina is a sign that the heart is not getting sufficient blood flow. This is usually due to narrowing of the arteries (atherosclerosis. It can also be the result of extreme hypertension, hypertrophic Cardiomyopathy or valvular heart disease. Stable angina is a pain that occurs when there is extra load on the heart and occurs in a regular pattern. This type of angina pain can be tackled with medication and rest. On the other hand, unstable angina can be dangerous as it may the precursor to a heart attack. The pain in such a case is more prolonged and severe. Prinzmetal's angina or variant angina pectoris occurs due to transient spasm of the coronary artery. This does not get triggered due to physical exertion.

The pain associated with angina is uncomfortable pressure and squeezing on the chest. There is pain or discomfort in the neck, shoulder and arms. But not all chest pains are signs of angina. ECG (electrocardiograph) helps in tracing heart activity. Exercise-ECG assesses your heart condition when you are on a treadmill. Beta-blocker drugs help prevent angina pain. Potassium channel blockers and calcium channel blockers aid in improving blood flow to the coronary arteries. Glyceryl Trinitrate or GTN tablets work instantaneously by relaxing blood vessels and easing the blood flow to the heart muscles. Aspirin is prescribed to reduce the probability of blood clots and reducing blood viscosity. Statin medicines are prescribed to reduce cholesterol levels. Angioplasty involves passing a tiny balloon into a large artery and then blowing it up inside to widen the artery. Bypass surgery is done to bypass the narrowed section of arteries and provide the heart with blood vessels that are not obstructed. Angina can be controlled with medication and lifestyle changes in diet and exercise.

• Quit smoking
  
• Control cholesterol levels
  
• Control blood pressure levels
  
• Regular exercise regimen
  
• Nutritious diet - low in fat, high in fibers, rich in fruits, vegetables and oily fish
  
• Maintain healthy body weight