How the heart works?

What is a heart disease?

What is a heart attack?

What is angina?

What is bypass surgery?

What is 'beating heart' or off-pump surgery?

Women and Heart Disease

Frequently Asked Question – After Bypass Surgery

It is made up of muscles and its main purpose is to pump blood, filled with oxygen to the organs and tissues, throughout the body

The heart has 4 chambers. The upper 2 chambers are called the right atrium and left atrium. The lower 2 chambers are the right and left ventricle, and have thick muscular walls

To pump the blood the ventricles contract. Each time your heart does that it is considered one heart beat. The heart usually beats between 60-90 times per minute. This is the pulse rate

The gets the blood and oxygen from the coronary arteries. There are 2 main coronary arteries, the left and right coronary artery

The left main coronary artery divides into 2 branches-the left anterior descending artery and the left circumflex artery

When we commonly refer to 'heart disease' we mean 'coronary heart disease', which happens when blockages build up in the coronary arteries

These blockages are called atherosclerotic plaques and the process by which they build up is called atherosclerosis. This is also called 'coronary artery disease'

Other forms of heart disease include, valvular heart disease, heart failure, and disorders of heart rhythm

A heart attack is injury or death of a part of the heart muscle. It is also called a 'myocardial infarction'. There are 2 major ways in which a heart attack can occur:

Blockages get worse: As the blockages get larger there is less blood flow to the heart muscle. At one point the heart muscle no longer can get the blood and oxygen it needs. When the blood supply is cut off for more than about 30 minutes, the heart muscle cells begin to die, and a heart attack occurs

The atherosclerotic plaque cracks: Most heart attacks are caused as a result of 'cracking' or 'rupture' of the plaque (blockage). The plaque becomes unstable and cracks, forming a blood clot which travels and completely blocks the flow of blood through the artery, and causes a heart attack

Angina is a pain or discomfort that is usually felt in the chest, and spreading to other parts of the body, such as the neck, jaw, shoulders or arms. In some cases discomfort is only felt in these areas and not in the chest at all.

The typical presentation of a heart attack is an unpleasant squeezing pain which typically occurs in the middle of the chest or the back

It often radiates to both arms or the throat and jaw, and is accompanied by sweating and / or nausea

This typical presentation does not always occur. Some may just experience heart burn, or 'stomach upset' not relieved by antacids or not related to food intake, breathlessness at rest, accompanied by a 'run down' feeling

Some may only experience chest 'pressure' and not 'pain', or pain only in the jaw, teeth or arms

Chew a tablet of aspirin

Place a tablet of sorbitrate (nitroglycerin) under your tongue. (if you have a prescription for it)

Keep the patient calm

Rush the patient to the hospital

ECG: This measures the electrical activity of the heart. A change in the ECG pattern can be indicative of the presence of heart disease. The doctor usually looks for two types of changes:
1. Those which indicate a block in the coronary arteries and
2. Those which indicate a problem with the rhythm of the heart beats, such as palpitations

Stress Test / Stress ECG: The stress ECG provides more information than a rest ECG since the oxygen demand on your heart is greater while exercising. A positive stress test indicates that there are changes on your ECG

Thallium Stress Test / Nuclear Medicine Stress Test: This stress test is similar to a regular stress test, but in this a dye is injected into the heart and pictures are taken of the heart, before and after the stress test.This can detect areas of the heart muscle that have been damaged by a heart attack and areas that are not getting enough oxygen due to partial blockages of the coronary arteries. Nuclear medicine tests can also provide information on the functioning of the left ventricle

This is a surgery in which a healthy blood vessel (artery) is used to form a detour (bypass) around a blockage in a coronary (heart) artery. The new blood vessel used is called a 'graft' and therefore the procedure is correctly termed as 'Coronary Artery Bypass Graft' surgery. The original blockage in the artery remains as it is, but now there is adequate blood supply to the heart muscle beyond the blockage. Today coronary artery bypass is one of the most frequently performed surgical procedures.

The 'graft' used can be either an artery or a vein. However, these days most advanced heart centers such as the Asian Heart Institute prefer to use 'arterial grafts' since they have been shown to have a longer life. Studies performed at the Cleveland Clinic by Dr. Floyd Loop and others have shown that arterial grafts remain open even after 20 years of surgery. When surgery is done only using arteries as grafts (also called 'Total Arterial Revascularization'), the chances of getting recurrence of angina are very slim, and in most cases the patient does not need a second bypass surgery. In the past 'venous grafts', usually from a vein in the leg called saphenous vein were used often, but they have a higher rate of developing fresh blockages.The most common artery used is an artery from your chest called the Left Internal Mammary Artery (LIMA). This artery is detached from the chest wall and the open end attached to the coronary artery below the blockage. The RIMA can also be used in select cases. The radial artery is another very commonly used conduit vessel in bypass surgeries. It's typically taken from the non-dominant hand.

To perform this delicate surgery the surgeons always used a heart-lung machine in the past. This machine allowed the heart to be 'stopped' for a while to perform the grafting. However, over the past few years some of the surgeons also perform the surgery on a 'beating heart' and do not use the heart-lung machine. In this method a device called 'OCTUPUS' is used and the surgery is done while the heart is beating. This method has several advantages but is technically more demanding. At the Asian Heart Institute almost all surgeries are done on the beating heart and have resulted in the patients spending less time in the ICU, less blood transfusions and complications as well as a shorter hospital stay.

Ask any woman which disease is she most afraid of, and the reply you will usually get is 'breast cancer'. The reality however is very different; heart disease kills more women than any other disease. This comes as a surprise to most, as heart disease was always thought to be a 'man's disease'. In fact, women are as much at risk for heart disease as men are, but are protected by their hormones till they reach menopause.

Another sad statistic is that a much larger percentage (42%) of women die within one year after having a heart attack, as compared to men (24%). The reasons for this are not well understood. One possible explanation is that women tend to get heart disease later in life and are therefore more likely to have coexisting chronic conditions. Some other little-known facts about women and heart disease are:

Women who smoke are at a risk of having a heart attack 19 years earlier than non-smoking women

Women with diabetes are three to seven times more likely to have heart attacks

Women are almost twice as likely as men to die after by-pass surgery

Women often do not have the typical symptoms of angina (chest pain radiating to the arms) or other symptoms associated with a heart attack. Therefore they are often not diagnosed correctly and in appropriate time

Women are 20% more likely than men to die in the hospital following a heart attack

Women receive less aggressive treatment than men for their heart disease

One area of women's health which has perhaps generated the maximum amount of controversy and confusion is hormone replacement therapy. Until recently it was thought that this therapy consisting of estrogen and progestin in varying combinations was protective for the heart. However, results from recent studies have contradicted these findings. The current scientific recommendations for hormone replacement are:

This therapy should be started only after consultation with a physician, preferably the gynecologist

Relief from the symptoms of menopause should be the primary reason for taking hormone replacement therapy

Hormone therapy should not be used to prevent heart disease

Hormone therapies have been shown to help build stronger bones; however, women should weigh the risks of hormone therapy before taking it to prevent osteoporosis