Saturday, May 26, 2012

Coronary Artery Disease - Diagnosis

Diagnosis


Many tests can diagnose possible heart disease. The choice of which (and how many) tests to perform depends on the patient's risk factors, history of heart problems, and current symptoms. Usually the tests begin with the simplest and may progress to more complicated ones.

Routine Tests to Determine Risk for Heart Disease

Doctors routinely check for high blood pressure and unhealthy cholesterol levels in all older adults. Specific tests are also important in people who may have risk factors or symptoms of diabetes.

Electrocardiograms (ECGs)

An electrocardiogram (ECG) measures and records the electrical activity of the heart. Between 25 - 50% of people who suffer from angina or silent ischemia, however, have normal ECG readings. The waves measured by the ECG correspond to when different parts of the heart contract and relax. Specific waves seen on an ECG are named with letters:

ECG
The electrocardiogram (ECG, EKG) is used extensively in the diagnosis of heart disease, from congenital heart disease in infants to myocardial infarction and myocarditis in adults. Several different types of electrocardiogram exist.
  • P. The P wave is associated with the contractions of the atria (the two chambers in the heart that receive blood from outside).
  • QRS. The QRS is a series of waves associated with ventricular contractions. (The ventricles are the two major pumping chambers in the heart.)
  • T and U. These waves follow the ventricular contractions.

The most important wave patterns in diagnosing and determining treatment for heart disease and heart attack are called ST elevations and Q waves.


Review Date: 05/05/2011
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)