Heart

Diagnostic Tests

If your physician is concerned about your risk for heart disease, he/she may order some diagnostic tests. These tests (listed in alphabetical order) might include:

Angiography
Angiography is performed using regular x-rays and is used to look at arteries of the neck, head and brain. Medication is directly injected into an artery of the leg or the arm and pictures are taken of the vessels. This is used to identify blockages or aneurysms of blood vessels. Coronary angiography is used to evaluate blockages in the arteries that supply blood to the heart. It's an important tool that helps doctors evaluate the number and severity of diseased coronary arteries.

Cardiopulmonary Exercise Stress Test
An exercise stress test is a test used to evaluate the heart's function while performing activities. A patient will walk on a treadmill until they are able to reach their maximum peak heart rate and the function of the heart will be recorded on an EKG. The procedure takes approximately 30 minutes. (See also Thallium Stress Test)

Digital Subtraction Angiography (DSA) or Magnetic Resonance Imaging/Angiogram (MRI or MRA)
This is a test that uses magnetic fields to generate an image of the head and neck and see the arteries in these structures. It records pictures by computer of the major blood vessels to the heart or brain. In this test, dye is injected into a vein in the arm and an x-ray machine quickly takes a series of pictures of the chest or head and neck. It is also able to detect blockages or aneurysms of arteries. This test may be ordered before certain surgical procedures are performed.

Doppler Ultrasound
This is an ultrasound test used to look at the arteries of the neck, upper extremities and lower extremities. It is also very useful in detecting blockages or aneurysms in blood vessels. The ultrasound waves are used to reconstruct an image of the carotid (or other) arteries and the status of blood flow through the artery.

Echocardiogram
An echocardiogram is a type of ultrasound technique used for viewing the heart. It is used to look at heart valve function, heart muscle function, and blood flow in the heart. It is able to measure the size of the heart, how the heart is working, how thick the muscle of the heart is and how the heart wall is moving. It is especially useful in diagnosing congenital heart disease, cardiomyopathies, and aneurysms. It can also identify tumors and clots in the heart. A transducer is placed on the outside of the body and the multiple images are recorded onto a videotape. The procedure takes approximately 30 minutes.

Electrocardiogram (EKG, ECG)
An electrocardiogram is a measure of the heart rhythms and electrical impulses. It is used to diagnose abnormalities of the heart's functions. Electrodes are attached to the patient's arms, legs and chest, and these leads record the electrical activity of the heart. The procedure takes approximately 10 minutes.

Holter Monitor
A Holter monitor is a portable EKG that can be worn underneath the clothes to monitor for any heart abnormalities. The main goal of the Holter monitor is to document and describe occurrences of abnormal electrical behavior in the heart. It is used to detect arrhythmia (irregular heart beats and palpitations), and ischemia (decreased blood supply to the heart muscle). It is worn 24 hours a day while the patient is performing normal daily activities.

Magnetic Resonance Imaging/Angiogram (MRI or MRA)
See Digital Subtraction Angiography

MUGA Scan (Nuclear Imaging)
The purpose of this test is to examine how well the heart is functioning as a pump. An intravenous (IV) line will be inserted for the test, and technetium, a radioactive substance that labels or "tags" red blood cells so they can be seen, will be administered. By counting these cells over numerous cardiac cycles, a nuclear camera can create an image of the heart's chambers and the larger blood vessels leading to and from it. The information obtained from this test will tell how much blood the heart ejects with each contraction (ejection fraction or EF), and how quickly this blood is ejected.

Positron Emission Tomography (PET Scan) (Nuclear Imaging)
Positron emission tomography of the heart visualizes various aspects of heart tissue function. PET combines CT scanning and radionuclide tracers to estimate regional heart blood flow, physiologic reactions and neurologic processes of the heart. It is very helpful in observation of cardiac physiology and pathophysiology (diseases of the body systems). PET is used for detecting, localizing and describing coronary artery disease that impairs blood flow to the myocardium. PET accurately identifies injured but living myocardium (heart muscle).

Single Photon Emission Computed Tomography (SPECT) (Nuclear Imaging)
The SPECT test involves taking a series of pictures around the chest after injecting a tracer (chemical that can be viewed) into the blood. Computer graphics are then used to create images of slices through the heart. These agents are injected either at rest or with exercise or Thallium stress testing. The SPECT test is used to make it easier to detect and localize myocardial (heart muscle) perfusion defects at rest and during stress. It is able to localize coronary artery disease and assess the extent and severity of perfusion (oxygen carried to the muscle) abnormalities.

Transesophageal Echocardiogram (TEE)
The TEE can be used in or out of the operating room to diagnose myocardial ischemia (poor blood supply to the heart tissue). TEE is used preoperatively to determine whether surgery is indicated. The patient is put in a twilight sedation and a probe is inserted into the mouth of the patient and into the esophagus. The physician is able to place the probe closer to the heart than a standard echocardiogram. TEE can facilitate diagnosis, allow the use of specific treatments and monitor interventions throughout an operation without disrupting surgical technique. The TEE is able to detect wall motion abnormalities and valvular leakage, confirm proper valve reconstruction and other surgical repairs, determine the cause of blood volume disorders and other intraoperative complications, and provide diagnostic information that could not be obtained preoperatively. This has enabled surgeons to correct inadequate repairs before patients leave the operating room. TEE is also used in assessment and treatment of patients in the hours and days after surgery. It has also reduced the need for re-operation, and has helped in a quicker diagnosis of complications around the operative period.

Thallium Stress Test (Nuclear Imaging)
The Thallium stress test is a type of nuclear scanning test or myocardial perfusion (blood flow) imaging test. It is usually done in conjunction with an exercise stress test on a treadmill or bicycle. When the patient reaches his or her maximum level of exercise, a small amount of a radioactive substance called thallium is injected into the bloodstream. The patient then lies down on a special table under a gamma camera that can detect the thallium. The thallium mixes with the blood in the bloodstream and enters the cells of the heart muscle. If a portion of the heart muscle is poorly perfused (doesn't receive a normal blood supply), there will be less than a normal amount of thallium in the heart muscle cells there. The first pictures are made shortly after the exercise test and represent blood flow to the heart during exercise. The heart is "stressed" during the exercise test, thus the name "stress test." The patient then lies quietly for two to three hours and another series of pictures is made. These show blood flow to the heart muscle in the resting state.