Ventricular arrhythmias during exercise testing: mechanism, response to coronary bypass surgery and prognostic significance.
To investigate the determinants and prognostic significance of ventricular arrhythmias during exercise testing, 86 patients with such arrhythmias were identified from a consecutive series of 446 patients who underwent treadmill exercise testing and cardiac catheterization. The prevalence of these arrhythmias was 19% in the total group but increased to 30% in the 120 patients with 3-vessel or left main coronary artery disease. Patients with exercise-induced arrhythmias were more likely to have 3-vessel or left main coronary artery disease, a lower resting ejection fraction, greater than or equal to 2 mm of ischemic ST depression and more severe segmental wall motion abnormalities than patients without this finding (p less than 0.05). Repeat exercise testing in 22 patients with exercise-induced arrhythmias after coronary bypass surgery revealed that persistence of these arrhythmias was associated with either severe wall motion abnormalities preoperatively or residual ischemic ST depression during the post-operative exercise testing. At a mean follow-up period of 5.3 years, the presence of exercise-induced ventricular arrhythmias was not associated with increased cardiac mortality in the medically treated patients.
D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000503:physiopathology*; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000401:mortality / Q000503:physiopathology* / Q000601:surgery; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000503:physiopathology; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011379:Prognosis; D013318:Stroke Volume