THE INCIDENCE OF ARRYTHMIAS IN PATIENTS UNDERGOING EXERCISE TREADMILL TEST

Abstract

Background: Although a silent ischemic ECG response to treadmill exercise in clinically healthy population is associated with an increase likelihood of future coronary events i.e angina pectoris, myocardial infarction or cardiac death, Patients with documented coronary artery disease have a greater susceptibility to sudden death if they demonstrate ventricular arrythmias. Objective: To determine the significance of arrythmias during exercise testing in suspected coronary artery disease patients and in noncoronary artery disease group. Method: We analyzed 1500 consecutive patients retrospectively for exercise induced arrythmias who presented to us from Nov 1998 to Nov 1999.Bruce and Modified Bruce Protocol were used all arrythmias recorded were included in the study as supra ventricular arrythmia, ventricular eg PVC, Premature Ventricular Contraction VT, Ventricular Tachycardia, and Heart Block Result were analyzed as per protocol. Results: Of 1500 that were analyzed 906 (60.4%) were negative for ischemia included 21 patients with negative stress test and previuos history of myocardial infarction 511(34.06%) were positive for exercise induced ischemia 83(5.53%) cases were inconclusive. During exercise and post exercise recovery phase 1237(82.4%) had no arrythmias, irrespective of the fact whether stress test was positive or negative for ischemia. Sub analysis for arrhythmia showed exercise induced arrhythmias in 264 (17.6%) patients and in 1237 (82.4%) had no arrhythmia patients with positive ETT or with previous history of MI showed arrhythmia's in 163 (26.5%) while. (10.42%) patients with positive stress test showed arrythmias required further evaluation whearas 146 (89.57%) were considered benign and 452 (73.49%) showed no arrhythmia. The group with negative ETT 885 (59%) with no previous cardiac history showed arrhythmia's in 101 (11.41%) patients and 784 (88.58%) showed no arrhythmia's. Conclusion: We conclude that exercise induced arrythmias are more common in patients with suspected and established coronary artery disease having positive stress test.