People who may have arrhythmias need to receive a thorough cardiac examination, which may include one or more of the following testing procedures:

History and physical examination. These are the first steps the doctor will take.

Electrocardiogram (ECG or EKG). This is a test in which several electronic sensors are placed on the body to monitor electrical activity associated with the heartbeat.

Signal-averaged ECG. A signal-averaged electrocardiogram is a more detailed type of ECG during which multiple ECG tracings are obtained over a period of approximately 20 minutes in order to capture abnormal heartbeats which may occur intermittently.  A computer captures all of the electrical signals from the heart and averages them to provide the physician more detail regarding how the heart's electrical conduction system is working.

Echocardiography. This is a method of studying the heart's structure and function by analyzing sound waves bounced off the heart and recorded by an electronic sensor placed on the chest. A computer processes the information to produce a one-, two- or three-dimensional moving picture that shows how the heart and heart valves are functioning.

Exercise stress testing. A common test for diagnosing coronary artery disease, especially in patients who have symptoms of heart disease. The test helps doctors assess blood flow through coronary arteries in response to exercise, usually walking, at varied speeds and for various lengths of time on a treadmill. A stress test may include use of electrocardiography, echocardiography, and injected radioactive substances. Also called exercise test, stress test, or treadmill test.

Tilt-table evaluation.This test measures your heart rate and blood pressure while lying flat, then monitors them as the table is tilted up. Position changes exert stress on the part of the nervous system responsible for maintaining heart rate and blood pressure, so physicians can observe the cardiovascular response under controlled conditions. The tilt-table evaluation, which takes between 20 and 45 minutes, is helpful for patients with syncope (blackout).

Arrhythmia monitoring devices. You may be asked to wear a Holter monitor, which records your heart rate and rhythm continuously for up to 24 hours at a time. Long-term monitoring - up to a month - may be performed with an event monitor, which records an infrequent arrhythmia and provides a way for your doctor to retrieve and save the data via computer recording.

Electrophysiology (EP) studies. During an EP study, which can be performed at the Texas Heart Institute at St. Luke's Episcopal Hospital's Cardiac Catheterization Laboratories, doctors insert one or more small wires through a vein in the leg or upper extremity and then guide them to the heart. Programmed electrical stimulation then reproduces your arrhythmia, allowing physicians to determine the nature and location of the rhythm disturbance. When drug therapy is begun or revised, EP studies allow doctors to gauge the heart's reaction to certain medications.

For more information about The Center for Arrhythmias and Electrophysiology, call (832) 355-6567 or (800) 238-4212.