The first step in a heart-disease diagnosis is a physical examination. Using a stethoscope, your doctor will listen for a heart murmur or other abnormal heartbeat sounds. This can reveal congenital defects, valve disease, or arrhythmia. Blood tests for cholesterol and triglycerides, cell counts, and other substances can also suggest evidence of heart disease.
Following that, there are several different tests that can examine the heart , including:
- electrocardiogram (EKG)
- computed tomography (CT) scan
- magnetic resonance imaging (MRI)
These tests will often be performed along with a stress test, with the patient running on a treadmill or riding a stationary bicycle. Many heart disease symptoms only appear when the heart has to beat harder and more quickly, and a stress test can reveal these.
This test uses ultrasound to create an image of the heart beating that is displayed on a video screen. It can detect valve malfunctions, congenital defects, and other problems. If the standard echocardiogram does not produce a clear enough picture, a variation called transesophageal echocardiogram (TEE) can be used. In this test, the patient swallows a small tube containing an ultrasound transducer that detects ultrasound waves from inside the body, as opposed to externally in a regulartransthoracic echocardiogram (TTE).
This test uses electrodes placed on the skin of the chest to detect the electrical signals emitted by the beating heart. It is used to monitor the heartbeat for irregularities. Sometimes the patient may wear a portable device that records a continuous EKG for up to several days. This can find transient abnormalities that may not show up on a standard EKG that only captures an isolated point in time.
A chest x-ray takes a stationary picture of the structures inside the chest, including the heart, lungs, and the major blood vessels that connect them. This test is often used to determine if the heart is enlarged and to determine if it is a heart or lung problem that is causing the patient’s symptoms.
Computed Tomography (CT) Scan
A CT scan uses a rotating x-ray machine to take multiple images of the body, creating a three-dimensional image. A CT scan of the heart can be more effective than a simple chest x-ray in visualizing problems.
Magnetic Resonance Imaging (MRI)
An MRI uses a powerful magnetic field combined with radio waves to create a three-dimensional image of the inside of the body (including the heart).
In this test, a small sample of heart tissue is extracted and examined under a microscope for abnormalities. This can be used to diagnose various forms of cardiomyopathy as well as heart infection and conditions such as iron overload (hemochromatosis) and abnormal protein deposits in the heart (amyloidosis)..
In a cardiac cathereterization, a long thin tube is inserted into a blood vessel in the groin, arm, or neck and threaded into the coronary arteries of the heart. It is then used to inject a dye that can be detected via x-ray, which allows doctors to observe how blood flows through the coronary arteries. (This dye procedure is also called angiography.) Cardiac catheterization is also used to perform cardiac biopsies. Oftentimes, if there are blockages in the arteries, the doctor may be able to place a stent (a special type of scaffolding) into the artery to keep it open enough for an adequate blood supply to feed the tissues of the heart.
Magnetic Resonance Angiogram (MRA)
An MRA is similar to cardiac catheterization but less invasive. Dye is injected into a vein or artery and then tracked using MRI as it travels to the heart. MRA can detect narrowing or blockages in the blood vessels that serve the heart, but it does not produce a picture as clear as cardiac catheterization.
There are several blood tests used to check for heart disease. Tests for blood cholesterol levels and triglycerides help gauge the risk of heart disease. White blood cell counts help determine if a heart infection is present. A test for a protein called B-type natriuretic peptide (BNP) can indicate heart failure and cardiomyopathy. Tests for bacteria in the bloodstream can suggest heart infection.
Blood tests can also be used to detect whether an individual has experienced a heart attack. Proteins called troponins may be elevated in a heart attack. This blood test, combined with the clinical picture, can help determined whether a heart attack has likely occurred.