Coronary Artery Disease by Henry Altszuler, MD, FACC
Everyone knows someone who was “fine” until they suffered a heart attack or died suddenly. These catastrophic events often make people wonder about their own risk of heart disease. Though the incidence of coronary disease (problems due to clogging of the arteries which supply blood to the heart) is declining, heart disease is still the #1 killer of both men and women in the U.S.
Coronary disease is caused by the build-up of fatty deposits inside the arteries that supply blood to the heart muscle. This process is called atherosclerosis. The deposits are also called “plaques”, and are made up of several components, including cholesterol. You can think of the process as similar to a water pipe, with corrosion and build-up of debris in the pipe. It takes a long time to corrode the pipe, and there is no noticeable decline in water flow until the pipe is significantly narrowed. As the narrowing worsens, the water flow slowly declines, and may suddenly stop altogether if the pipe is completely obstructed. In the coronary arteries, the beginnings of plaques often start when we are in our 20’s. They grow silently until later years, when some people begin to suffer the consequences of severely narrowed arteries. Typically, patients with severe narrowing in the coronary arteries experience angina (chest pain or tightness or shortness of breath) with exertion or emotional upset, or, when the artery is completely obstructed (with a blood clot), heart attacks. Some people with severe narrowing have no symptoms at all or very atypical symptoms. Unfortunately, it is often impossible to tell which people have dangerous plaques (also called “vulnerable” plaques) using routine screening tools (like EKG, stress tests and physical examination). More invasive tools are available, but it is important to use them only in people whose risk of heart disease is high enough to warrant them since these tests carry risks of their own.
Since the atherosclerotic process takes so long to develop, it is logical to try to prevent the mild plaques from growing, and most importantly, we need to prevent vulnerable plaques from leading to sudden heart attacks, which can cause an irregular heartbeat and “sudden death”, which is a cardiac arrest due to the irregular heartbeat. The challenge is to determine who is at risk. The good news is that once the “at-risk” individuals are identified, there are effective ways to reduce risk and to monitor progress.
The first step in determining your risk for coronary disease is to add up your “risk factors”, which are conditions that make it more likely that you will develop coronary disease. There are actual risk “scores” that you and your doctor can calculate based on some simple measures that everyone should have. The common risk factors for coronary disease and heart attack are: male sex, family history of early coronary disease, diabetes, high blood pressure, high cholesterol, and smoking. Other conditions, such as obesity and stress play a lesser role. The more of these risk factors you have, the higher the risk, but even if you have all of these risk factors, it does not necessarily mean you have a problem.
People with multiple risk factors, or with symptoms that may be due to heart disease, often undergo further tests to look for possible coronary disease. Currently, there are two different types of tests that are useful. One is a stress test, in which you walk on a treadmill while connected to an electrocardiogram machine. This test may also include the injection of a radiotracer (nuclear stress test) to more accurately determine whether there is adequate blood flow to the heart muscle. The other type of test uses a CAT scanner to either look for calcium deposits in the coronary arteries, or to perform a non-invasive angiogram to look at the actual pattern of plaque buildup (if any) in the arteries. Each type of test has specific advantages and disadvantages, which are best discussed with your doctor. If severe arterial blockages are identified on these non-invasive tests it may be necessary to do more invasive testing, such as cardiac catheterization. This test identifies the pattern and severity of blockage and allows your doctor to determine the best treatment for you. Possibilities include medicine only, coronary angioplasty (including stents), or bypass surgery. Not everyone with blocked arteries requires surgery or angioplasty, so these decisions are made individually with your doctor.
Even without going through the testing outlined above, it makes sense to reduce your future risk of coronary disease by modifying the risk factors that you have control over. This includes stopping smoking, getting adequate exercise, watching your diet, and checking (and controlling) your blood pressure, cholesterol, and sugar levels. Taking low dose aspirin may also help prevent heart attack in some people, but since aspirin also has potential side effects, this should be discussed with your doctor.
If you think you may be having a heart attack, call 911 immediately. Time is critical when treating heart attacks. By calling 911, you alert the hospital in advance, so that the heart attack treatment team can be mobilized more quickly. You also help avoid complications which may occur on your way to the hospital.
Learning CPR is a great way to help others avoid the most serious consequences of heart attack (and other serious conditions such as choking and drowning). If someone stops breathing CPR in the first few minutes (before help arrives) is often the difference between life and death. Anyone can learn CPR. You can contact the American Heart Association to find a course near you.
Angina: chest discomfort due to narrowed coronary arteries
Atherosclerosis: process of fatty plaque buildup in the arteries
Angioplasty: use of a balloon or stent to stretch an artery that has narrowing due to atherosclerosis
Plaque: the fatty material that builds up within arteries
Vulnerable plaque: “sticky” plaque that is prone to blood clot formation and heart attack
Heart attack: damage to heart muscle caused by closure of a coronary artery by blood clot (also called myocardial infarction)
Coronary artery: artery that supplies blood to the heart muscle