What Is Coronary Artery Disease?
"For every patient, there is an appropriate test. If one test is not giving us the answer we're looking for, we always have another, whether it's an angiogram, ultrasound, or checking the pressure gradient in the arteries. We have everything we need right here in the cath lab to give patients the answers they need" says Annapoorna Kini, MD, Professor of Cardiology and Associate Director of the Mount Sinai Cardiac Catheterization Lab.
Coronary artery disease (CAD) is the most common form of heart disease. In CAD, fatty deposits known as plaque collect on the inner wall of the blood vessels. Over time, the plaque thickens and arteries narrow, making it harder for the heart to pump blood throughout your body. This is known as atherosclerosis and when left untreated, can lead to a heart attack.
What Is a Heart Attack?
A heart attack occurs when oxygenated blood cannot get to a section of your heart. That section becomes damaged from lack of oxygen and begins to die. Heart attacks usually stem from coronary artery disease.
Sometimes heart attacks occur without any warning, called silent heart attacks although most people experience some sort of symptom before the actual attack. The most common symptoms are chest pain (pressure, squeezing, or discomfort in the chest) or pain in the upper body, arms, back, neck, jaw, or stomach. Occasionally, patients have difficulty breathing, experience nausea or vomiting, or break out in a cold sweat. As with CAD, women are more likely to have atypical symptoms, especially if very young or very old. The important thing to remember is that symptoms vary, so if you feel like something is not right, listen to your body and get help.
If we suspect that you have had a heart attack, we start by providing oxygen and medications such as aspirin (to prevent blood clotting) and nitroglycerin (to relieve chest pain). We work to restore blood flow to your heart. If the attack was caused by a blood clot in your heart, we may use medication to dissolve the blood clots or perform an angioplasty, an emergency procedure that opens up the blockage in the artery or to stop additional clotting, reduce the strain on the heart, and prevent further attacks.
Common risk factors for coronary artery disease include age, diet, diabetes, high blood pressure, high cholesterol, obesity, physical inactivity, smoking, and stress.
Gender, Ethnicity, and Family History
Additional factors such as gender, ethnicity, and family history may also contribute to your risk of coronary artery disease. Men are at a greater risk for CAD and develop it at younger ages than women. There are numerous specific risk factors for women including being postmenopausal, having undergone early menopause, or having a history of metabolic syndrome or polycystic ovarian disease.
Ethnicity also contributes to one’s risk for developing coronary artery disease. For example, African Americans are at higher risk for early death and have higher mortality rates from cardiovascular problems in general, and African American women with CAD are more likely to have a heart attack than white women.
Gender is important as well. While coronary artery disease is often considered a men’s problem, more women than men die each year of the disease. In fact, women are more than 10 times more likely to die of CAD than breast cancer. "It's important for women to understand that heart disease is also a woman's disease," says Mary Ann McLaughlin, MD, Associate Professor of Cardiology and Director of the Women's Cardiac Assessment and Risk Evaluation Program. "The warning signs of heart attack in women can differ from the classic ones, and Mount Sinai cardiologists are well versed and very knowledgeable about the specific risks for women."
There is a genetic component to heart disease. If a family member develops coronary artery disease before age 50, relatives should enroll in a heart disease screening program to receive lifestyle counseling and preventive care.
Cholesterol is a soft fat-like, waxy substance found in the blood. Our bodies, which naturally produce most of our cholesterol (75 percent), use it to repair cells, produce hormones, and perform some body functions. The rest comes from what we eat. If we have too much cholesterol in our blood, it can contribute to plaque build-up in the arteries, which can then lead to coronary artery disease, heart attack, and stroke.
There are three types of cholesterol, and each affects our risk of coronary artery disease.
- Low-Density Lipoprotein (LDL or “bad” cholesterol) deposits in arteries and makes them more rigid or leads to plaque build-up in the arteries, which causes coronary artery disease. High LDL levels increase the risk of coronary heart disease.
- High-Density Lipoprotein (HDL or “good” cholesterol) transports cholesterol from arteries back to the liver, which lowers levels of cholesterol in the blood. Higher HDL levels protects against risk of coronary heart disease. Women have high HDL in premenopausal years due to estrogen. Smoking decreases HDL.
- Triglycerides are a type of fat found in your blood. We usually see high levels of triglycerides in patients who are overweight or inactive, who smoke or drink heavily, and/or who eat a lot of carbohydrates. Women, in general, have higher triglycerides levels than men.
Signs and Symptoms
The signs of coronary artery disease and heart attacks are not as dramatic in real life as they are in the movies. Off-screen, they tend to be subtle and range from mild discomfort to extreme pressure or pain. Symptoms may include:
- Feeling of a heavy weight on the left side of your chest
- Pressure, tightness, and a squeezing pain in your chest (called angina)
- Shortness of breath
- Pain radiating down your arm, shoulders, jaw, neck, and back, particularly on the left side
- Dizziness, sweating, weakness
- Anxiety, feeling of impending doom
- Indigestion, nausea, vomiting
Symptoms may be different for females. Women are less likely to have chest pain and their symptoms are more likely to include cold sweats, excessive fatigue, and pressure in the chest or middle of their back.
If you experience one or more of these symptoms, please seek medical attention immediately.
Detection and Diagnosis
It's easy to identify coronary artery disease after someone suffers a heart attack. It is more challenging to detect it in people who show no signs or symptoms of heart disease. And that is becoming increasingly important. “The whole paradigm is shifting away from targeting the person who is at the edge of the cliff, and toward identifying the patient well before he reaches that edge," says Jonathan L. Halperin, MD, Professor of Cardiology and Director of Clinical Cardiology Services. "It's not only being able to identify the disease when it is there, but identifying it before it is threatening."
At Mount Sinai Heart, we use imaging technologies to screen for CAD including:
- Exercise Stress Testing involves having patients exercise on a treadmill while clinicians monitor your heart.
- Nuclear Stress Testing combines exercise or medical stress testing with nuclear images of blood flow to the heart.
- Calcium Scoring Tests for hard plaque build-up in artery walls.
- Echocardiography uses sound to form a moving picture of the heart; we can combine this with stress testing.
Mount Sinai Heart has the most advanced diagnostic tools available. We have the newest generation of nuclear cardiology cameras available for clinical use. This technology offers increased speed of imaging, decreased radiation dose, and potential for new applications, such as measurement of coronary flow. "I believe that the new technology will improve patient safety, comfort, and accuracy of diagnosis," says Lori B. Croft, MD, Associate Professor of Medicine and Director of the Nuclear Cardiology Laboratory.
Our state-of-the-art diagnostic tools include:
- Computed Magnetic Resonance Imaging delivers detailed images without using radiation.
- Computed Tomography Angiography provides 3-D imaging of the major blood vessels of the heart.
- Diagnostic Catheterization gives us angiogram X-ray images by using a catheter threaded from a blood vessel into the heart.
- Intravascular Ultrasound measures blood flow to determine which type of angioplasty to use.
We also pair magnetic resonance imaging (MRI) machines with positron emission tomography scanners to gather information. "Because the MRI has a great resolution, we can see things in three dimensions,” says Zahi A. Fayad, PhD, Professor of Cardiology and Director of the Translational and Molecular Imaging Institute. “We are going beyond anatomy to see signs of sickness on the cellular level."
For patients with a history of heart attacks, we use newer echocardiographic techniques to assess the impact of coronary disease on the heart’s function. These tests can confirm a diagnosis and can also predict long-term outcomes, helps us determine a treatment plan, and judge the risk of cardiac events.
In addition, our cardiologists use creative, hands-on methods to identify heart disease. Valentin Fuster, MD, PhD, Professor of Cardiology and Director of Mount Sinai Heart, sometimes asks patients in his office to do a series of sit-ups, then listens to their hearts. Dr. Fuster's diagnostic skills, honed by decades of experience, enable him to tell just by hearing your heart after exertion whether blocked arteries have caused the vessel walls to stiffen.
We usually treat CAD with medications such as aspirin, cholesterol- and blood pressure-lowering medications, and lifestyle modifications, such as weight control, diet, and exercise.