Diagnosing Heart Disease: The 8 Key Tests You Need to Know

The heart is a complex muscle. Like a car engine, it has multiple parts and connects to key organs around it. Both an engine and a healthy heart require all parts to do their job, or trouble can ensue.

“[The heart] has chambers, it has valves, but it also has its own electrical system,” says Paul Knoepflmacher, MD, clinical instructor in medicine at The Mount Sinai Hospital. “It also has blood vessels in it, and any of these components can go wrong and have problems.”

That means a single test may not be able to fully diagnose heart disease, or the extent of it. To get the most accurate picture and treatment game plan, doctors have a variety of tests to examine the heart’s function and the effectiveness of each of the heart’s individual components.

While doctors have a lengthy list of tests to choose from, your doctor won’t use every single one. “You really direct the tests to the patient’s needs,” says Nieca Goldberg, MD, medical director at NYU Langone Health, Joan H. Tisch Center for Women’s Health.

Tests to diagnose heart disease

Your doctor may want to test for heart disease if you have symptoms of heart disease or have significant risk factors like high blood pressure or high cholesterol. These are some of the tests they may use.

EKG (electrocardiogram)

An EKG records the electrical activity of the heart and its contractions. EKGs are used for any patient who’s showing symptoms of heart disease, like fatigue or shortness of breath, according to Satjit Bhusri, MD, cardiologist at Lenox Hill Hospital.

Echocardiogram

This test might be used if your EKG results are abnormal. “An echocardiogram is basically a test that uses sound waves to get an image of the heart,” says Dr. Knoepflmacher. (It’s similar to an ultrasound that pregnant women get to see their baby in the womb.) It gives doctors a good look at how blood is flowing in the chambers and valves of the heart.

Cardiac stress test

A stress test measures how well your body handles a workload by monitoring its activity during and after exercise, according to the American Heart Association (AHA). You will walk or run on a treadmill under the supervision of a doctor, and an electrocardiography machine will measure your heartbeat.

Nuclear stress test

A nuclear stress test lets doctors see photos of your heart after exercise using a special camera.

Stress echocardiogram

A stress echocardiogram compares ultrasound pictures of the heart before and after exercise, according to Michelle Weisfelner Bloom, MD, cardiologist at Stony Brook University Medical Center.

Coronary angiogram

A coronary angiogram (or cardiac catheterization) uses dyes to take X-rays of the arteries, according to AHA. A thin catheter is inserted into an artery from your groin or arm, and up to the heart. A special dye in the catheter lights up the arteries and makes them visible on the X-ray.

This test can “determine if there’s a blocked artery that needs opening,” says Dr. Goldberg. If a major blockage is discovered during a coronary angiogram, an angioplasty may be done, which is a procedure in which a balloon is inserted to the blockage and expanded to open up the artery. After that, doctors may insert a stent (a wire mesh tube) to keep the artery open after the procedure.

Cardiac CT scan

A cardiac CT scan is another way to check the health of your arteries. It takes X-rays of the heart and blood vessels to check for calcium buildup in the arteries. Using a measuring system called a “calcium score,” doctors can predict your risk of having a heart attack and assess how aggressive treatment should be, according to AHA.

Cardiac MRI

A cardiac MRI can be a very helpful, noninvasive diagnostic tool, which can help show the heart's pumping and relaxing function, and may even be able to diagnose myocarditis, among other conditions.

If your doctor requests certain tests to diagnose your heart symptoms, it’s a good idea to get informed. You want to understand “what the test is about, what it’s used for, and why your doctor has recommended it,” says Dr. Weisfelner Bloom. As always, asking your doctor plenty of questions can empower you to make the best choices for your health.