Coronary artery disease (CAD), also referred to as coronary heart disease, is a thickening of the small blood vessels, the coronary arteries, that supply blood, oxygen, and nutrients to the heart muscle. When cholesterol and fat collect inside the coronary arteries and narrow the passage, heart muscles are deprived of oxygen and nutrients. This can cause conditions such as arrhythmia (an irregular heart beat) or angina (chest pain or discomfort that results from poor blood flow through the vessels to the heart muscles). When blood supply to a portion of the heart muscle is blocked completely, the portion of the heart muscle may stop working, resulting in a heart attack.

Coronary artery disease is the leading cause of death in men and women in America. According to the World Health Organization (WHO), coronary artery disease, or CAD, kills more than seven million people each year. And the WHO predicts that in 2020, 11.1 million people will die from CAD.

Angina is a symptom of coronary artery disease that feels like a tightness in the chest. It first occurs during exercise or stress, both of which force the heart to pump harder. Generally, the feeling will only last a few minutes and go away while a person is at rest. If your arteries are severely blocked by more than 70 percent, angina will occur even at rest, because the heart is always working harder to pump blood.

Women may experience different symptoms than men. Instead of tightness in the chest, women frequently experience a burning sensation in the shoulders, arms, neck, jaw, or back.

There are a great number of risks that lead to coronary artery disease. Many of them are preventable, known as modifiable risks, while others, called non-modifiable risks, cannot be altered. The more risk factors you have, the higher your likelihood of developing CAD.

Most risk factors can be broken down into three categories: conditions, hereditary, and behavior.

Medical Conditions

• High Blood pressure

When pressure of blood in the arteries is high, it causes the arteries to work harder which, over time, can narrow and harden the arteries, making it difficult for the heart to pump blood. High blood pressure, also known as hypertension, is a modifiable risk.

• High Blood Cholesterol

Cholesterol is a modifiable risk, responsible for the formation of plaques in your arteries. If there is an abundance of cholesterol in the body, it cannot be processed fast enough and is deposited in the arteries.

There is a differentiation between “good” and “bad” cholesterol. High-density lipoprotein (HDL) cholesterol is considered “good” and actually helps to defend against heart disease. Low-density lipoprotein (LDL) is considered “bad” cholesterol. Too much “bad”, or too little “good” can cause heart disease.

• Atherosclerosis

Atherosclerosis is a condition that leads to coronary artery disease. It occurs when a collection of fat and cholesterol deposits - known as plaque - builds up on the inner walls of the arteries. This causes a blockage and reduces the flow of oxygen-rich blood.

It is rare for atherosclerosis to cause symptoms until the artery is already blocked. It can develop undetected over years, eventually leading to coronary artery disease.

• Diabetes

Diabetes and heart disease are fatally linked. Around 75 percent of people with diabetes die from a heart or blood disease. When the body is unable to make insulin, sugars build up in the blood, causing blockage.

• Sleep Apnea

Sleep apnea affects a person’s breathing cycle while they sleep, resulting in shallow breathing or a complete stop in breathing for short periods of time. This can increase blood pressure and the risk of heart problems.

Heritable

Family members with a parent diagnosed with heart disease before the age of 50 are more likely to develop heart disease themselves.

Behavior

Behaviors are modifiable risks:

• Obesity

A high amount of body fat increases the likelihood of someone having other risk factors for CAD, putting added stress on your entire body. 

• Smoking

Smoking increases blood pressure by constricting the blood vessels. The chances of a heart attack increases three times for men and six times for women who smoke at least a pack a day.

• Stress

Uncontrolled stress can affect the arteries and trigger a heart attack.

• Poor Diet

A diet high in cholesterol, fat, or sodium contributes to the thickening of arteries and high blood pressure.

• Alcohol

High alcohol intake can not only damage the heart, it can also increase blood pressure.

In addition to medical conditions, heritable, and behavior, non-modifiers such as age and sex play a part in coronary heart disease. Men are at a greater risk of CAD than women, and chances of coronary artery disease, for both men and women, increases naturally with age.

There are a number of tests available for diagnosing coronary artery disease. Typically, CAD cannot be confirmed with a single test, so often, a series of tests will be performed.

Doctor’s exam

The doctor will begin by asking about your medical and family history. The doctor will also ask about your symptoms and if you are experiencing pain in your chest.

A physical exam checks your skin for normal color. This indicates that blood is pumping properly. This exam also checks the pulse and the sounds of the heart. If a murmur or clicking sound is heard, this may indicate problems. Finally, the doctor will check your blood pressure.

Blood test

A blood test measures cholesterol, sugar, and protein in the blood to determine if you are at risk for CAD.

EKG or electrocardiogram

An EKG examines and records the electrical signals traveling through your heart. It is a non-invasive procedure that helps determine the speed and strength of your heartbeats, and whether you have had a heart attack in the past or are at risk of having one in the future.

Echocardiogram

An echocardiogram is also noninvasive and uses an ultrasound to create images of your heart. This is good for identifying trouble spots where blood is not flowing properly.

Stress Test

A doctor will evaluate you as you exercise and measure how your heart responds. If the heart has trouble pumping blood through narrow arteries, a stress test will recognize irregularities. Physically, you may become short of breath or even be unable to complete the test. Your heart rate and blood pressure may change dramatically, also indicating a problem.

Nuclear Scan

A nuclear scan uses a small dose of radioactive tracers, injected into a vein. Once the tracer has entered the heart, a special camera takes pictures to determine how the blood moves through the heart. Sometimes this is combined with a stress test to see how the blood flows during exercise.

MRI

Magnetic resonance imaging uses magnets and radio waves to take moving images of your heart. Sometimes an MRA, or magnetic resonance angiogram, is performed where a dye is injected in your blood to see how it moves through the heart.

CT

A CT scan, also known as computerized tomography, uses both an X-ray and a computer to create a detailed, three-dimensional image of the heart. This image helps a doctor see the arteries, and whether calcium is present in fatty deposits. A high amount of calcium may indicate coronary artery disease.

Coronary Angiogram (Cardiac Catheterization)

This is an invasive procedure that examines the blood vessels in a person’s heart. A catheter is guided to the arteries in the heart, and a dye is injected. The dye is visible through X-ray, which shows the path of the dye through the heart.

It has a number of purposes, including:

• Confirming the existence of heart disease

• Determining heart muscle function

• Measuring blood pressure and oxygen in the heart.

Coronary artery disease can develop over many years. If it goes undiagnosed, a person can develop complications that range from minor to major. Angina and arrhythmia occur when blood is being prevented from reaching the heart. As plaque builds up and continues to block the arteries, it increases the chance of a heart attack. If the heart attack is not attended to immediately, heart failure and death can occur within minutes.