Arrhythmias (Heart Rhythm Disturbances) Diagnosis
Arrhythmias may be identified either during routine health check-ups or when you first report having symptoms. In either case, the doctor will ask about your symptoms and medical history, and perform a physical exam, which includes listening to your heart. For older patients and those with symptoms or risk factors for heart disease, the healthcare provider will focus extra attention on cardiovascular health.
Tests may include:
Blood Tests—These tests evaluate your overall health, the function of your kidneys, the levels of various electrolytes, and may provide clues about your heart's health.
Urine Tests—These tests assess your general health and look for certain markers in the urine that may determine what is happening with your heart.
Electrocardiogram (EKG)—The EKG records the heart's activity by measuring electrical currents that travel through the heart muscle. This test can detect damaged areas of heart muscle and abnormal beats.
Exercise Stress Test—An EKG is used to record the heart's electrical activity during increased physical activity, such as exercising on a treadmill or stationary bicycle. For patients who are not able to exercise on a treadmill, a medication may be given intravenously that causes the heart to work harder, simulating a condition of physical exercise.
Echocardiogram—High-frequency sound waves (ultrasound) are directed at your heart to examine the size, shape, and motion of the heart. A more specialized version uses the Doppler effect to visualize blood flow.
24-hour Holter Monitor—If your rhythm disturbance does not happen in the doctor's office, you may be given a portable EKG machine to take home with you. The machine will be belted around your waist and will record your heart rhythm over 24 hours or more.
Transtelephonic Monitoring—Instead of a 24-hour monitor, you may take home a device that allows you to send your EKG recording over the telephone at the moment you feel symptoms of an arrhythmia.
Implantable Loop Recorder—Sometimes, a longer period of recording is necessary. A small, about 2" x 1" rectangular recording device may be surgically implanted underneath the skin of the chest. This device can record EKG-like information over a longer period of time. If the information recorded falls within certain normal limits, the device erases the data. Any episodes of abnormal heart rhythms are retained in the device until retrieval by the physician.
Nuclear Scanning—A radioactive material is injected into a vein and observed as it is absorbed by the heart muscle. This test is not specific for rhythm disturbances. It is used to visualize the blood supply to the heart. Areas with poor blood supply can potentially generate abnormal rhythms.
Cardiac Catheterization and Coronary Angiography—A more precise view of blood flow to and through the heart is obtained by threading catheters into the heart and injecting x-ray dye. This test is not used specifically for detection of heart rhythm disturbances, but rather to evaluate for presence of coronary artery disease (a common cause of heart arrythmias).
CT and MRI Angiography—This test combines the use of traditional CT and MRI with angiography. Certain dyes injected into your circulation can produce better pictures of blood vessels and other structures of the heart than CT or MRI alone.
Electrophysiologic Testing—For complex rhythm disturbances, and as a prelude to invasive treatment of arrhythmias, it may be necessary to map the spread of electrical impulses within the heart muscle. In order to accomplish this, the electrode is threaded through the blood vessels to various spots within the heart.
Tilt Table Testing—This test is usually ordered for patients with fainting episodes. Your heart rate and blood pressure are closely monitored while you are first lying flat on a table and then when the table is tilted.
Bruce GK, Friedman PA. Device-based therapies for atrial fibrillation.
Curr Treat Options Cardiovasc Med.2005;7(5):359-370.
Crawford MH, Bernstein SJ, Deedwania PC, et al, for the American College of Cardiology/American Heart Association task force on practice guidelines. ACC/AHA guidelines for ambulatory electrocardiography: Executive summary and recommendations.
Harrison's Principles of Internal Medicine.16th ed. McGraw-Hill; 2004.
Heart Rhythm Society website. Available at:
Krahn AD, Klein GJ, Skanes AC, Yee R. Insertable loop recorder use for detection of intermittent arrhythmias (review).
Pacing Clin Electrophysiol.2004;27(5):657-664.
National Heart, Lung, and Blood Institute website. Available at:
Rosano GM, Rillo M, Leonardo , et al. Palpitations: What is the mechanism, and when should we treat them?
Int J Fertil Womens Med.1997;42:94.
Weber BE, Kapoor WN. Evaluation and outcomes of patients with palpitations.
Am J Med.1996;100:138.