No abstract

SUMMARY The prevalence and cineangiographic correlates of exercise-induced inversion of U waves were studied in 248 patients. Exercise-induced U-wave inversion was observed in 36 patients (15%), of whom 35 had > 75% stenosis in one or more of the major coronary arteries. The proximal left anterior descending or left main coronary artery was involved in 33 of these patients, including 24 patients with no electrocardiographic evidence of anterior myocardial infarction. Exercise-induced U-wave inversion was observed in the absence of an abnormal ST-segment response in eight of the 166 patients (4.8%) with coronary artery disease, and five of these patients had a normal resting 12-lead ECG. Only one of the 82 patients (1.2%) without significant coronary artery disease demonstrated exercise-induced U-wave inversion, and this patient had a primary cardiomyopathy. We conclude that exercise-induced inversion of the U-wave is highly predictive of significant coronary artery disease and, more specifically, of disease of the proximal left anterior descending coronary artery.INVERTED U WAVES in the left precordial leads of a 12-lead ECG have been described in patients with left ventricular hypertrophy and coronary artery disease.' Similarly, the development of U-wave inversion during exercise has been described as an indicator of coronary artery disease and exercise-induced myocardial ischemia.2 3 The coronary cineangiographic correlates of exercise-induced U-wave inversion have not been reported. We previously reported an apparent high prevalence of disease of the proximal left anterior descending coronary artery in patients with exercise-induced inversion of U waves.4 This study of 257 consecutive patients who underwent treadmill exercise testing and coronary arteriographic studies was undertaken to determine the prevalence and coronary cineangiographic correlates of exercise-induced Uwave inversion. were six patients with electrocardiographic evidence of left ventricular hypertrophy by the Estes criteria5 and three patients with resting U-wave inversion. These nine patients were excluded from further study, leaving 248 patients. There were 190 males (77%) and 58 females (23%), mean age 51 years (range 19-73 years). Twenty patients were taking a digitalis preparation, 91 taking propranolol, 92 taking long-acting nitrates, four taking quinidine and one taking disopyramide. Two hundred seventeen patients had a history of chest pain and 126 were considered to have typical exterional angina pectoris. Nine patients underwent cardiac catheterization as a part of an evaluation for refractory ventricular arrhythmias and 10 asymptomatic subjects were evaluated because of an abnormal treadmill exercise test. The remaining 12 patients underwent cardiac catheterization for other reasons. Thirty-eight patients had electrocardiographic patterns of anterior myocardial infarction. They were considered as a separate subgroup because patients with these electrocardiographic patterns would be expected to have a high incidence of significant...

A group of 916 apparently healthy men between the ages of 27 and 55 years (mean 37) were followed up with serial medical and exercise test evaluations for a period of 8 to 15 years (mean 12.7) to determine (1) the prevalence and specific types of new coronary events observed in subjects with and without abnormal ST segment responses to exercise and (2)

Two-dimensional echocardiograms were done during rest and after exercise in 95 patients who subsequently had coronary arteriography. Prior myocardial infarction was present in 36 patients, 35 of whom had wall motion abnormalities. There was no evidence of prior infarction in 59 patients, 44 of whom had coronary disease. In these 44 patients, the exercise electrocardiogram showed ischemia in 19, was normal in 13, and was nondiagnostic in 12. Exercise echocardiograms were abnormal in 35 of these 44 patients. In 15 patients without coronary disease, the treadmill response was nondiagnostic in 6, ischemic in 1, and normal in 8. Exercise echocardiograms were normal in 13 of these 15 patients. We conclude that exercise echocardiography is a valuable addition to routine treadmill testing. It may be of special value in patients with an abnormal resting electrocardiogram or a nondiagnostic response to treadmill testing or when a false-negative treadmill test is suspected.