Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
A health care professional will ask questions about the patient's symptoms, medical and surgical history, lifestyle, and medications. The physical examination will focus on the heart and other organs, such as the lungs, that might explain the reason for the symptoms.
Other tests are likely to be done to confirm the diagnosis of PSVT and to assist the health care professional in tailoring the most appropriate treatment. Most commonly, an electrocardiogram (ECG) is done and testing includes the following:
Electrocardiogram (ECG): The ECG is a painless, quick, noninvasive test that detects the electrical activity of the heart. Through 12 electrodes, or leads, attached to the chest, arms, and legs, tracings or waves are detected and represent the electrical activity of the heart from 12 different views. This allows detection of a number of different kinds of problems in the heart. The ECG can help identify many different arrhythmias including PSVT and in some cases its underlying cause. However, further tests or even therapy may depend on the findings of the ECG.
ECG from a patient with PSVT
Ambulatory ECG: By the time a person reaches a medical facility, the symptoms will sometimes have stopped and the ECG will be normal. This is frustrating to the patient and the doctor because an accurate diagnosis depends on capturing the rapid heartbeat on an ECG. Ambulatory monitoring often solves this problem by monitoring the heart over a period of time, usually 1-2 days. The ambulatory ECG is more likely to document any abnormal heart rhythms that a person may experience. The patient wears the monitor device, called a Holter monitor, while they go about their daily activities. Patients also keep a diary while wearing the device to allow the health care professional to detect any abnormalities on the ECG recording during times when the patient has symptoms.
Echocardiogram (ECHO): This is a noninvasive ultrasound examination of the heart. A small handheld device is passed over the chest. It transmits pictures (sonograms) of the heart walls and valves to a television screen. It also measures how well the left ventricle is pumping. The echo is used to screen for any problems in the heart structure, valves, or muscles. The echocardiogram is used frequently in patients with SVT's that are irregular, but infrequently in PSTVs.
Stress test: The stress test is an ECG done both at rest and while the heart is under stress, usually with exercise on a treadmill or an exercise bicycle. If a patient cannot exercise, they can be given a drug that will temporarily "stress" the heart. This test helps in the diagnosis of coronary heart disease, that is, blockage of the coronary arteries by fatty plaques (atherosclerosis). Coronary heart disease prevents the heart from getting enough blood, and this can cause abnormal heart rhythms. This test is used in some patients who may have stress-induced PSVT and for other heart-related problems, such as poor blood supply to the heart (ischemia).
Cardiac catheterization and coronary angiography: If the stress test result is abnormal or if the patient has chest pain, shortness of breath, or loss of consciousness, he or she may undergo cardiac catheterization under local anesthesia to assess disease in the heart and heart valves. Angiography is a type of imaging study that uses a dye in the arteries to highlight blockages and damage. Usually, this test is not done in patients with PSVT unless they have significant risk factors for coronary artery disease and severe symptoms.
Electrophysiologic study: Patients may need this test if they have rapid heartbeats, but their body does not tolerate treatment, or if the heart has created new electrical pathways that contribute to the abnormal rhythm. This test involves placement of several pacemaker electrodes into the heart chambers to record electrical activity. The electrodes are placed via a catheter that is threaded through the veins to the heart, under local anesthesia in the cardiac catheterization lab. This test is rarely used in patients with PSVT.
Blood tests may be performed to rule out thyroid disease and evidence of heart muscle damage due to coronary artery disease (heart attack).
Urine tests and additional blood tests may be performed to rule out abnormal levels of drugs or illegal drugs that can cause rapid heartbeat.