Exercise-induced U-wave inversion as a marker of stenosis of the left anterior descending coronary artery.

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...

Distinct U Wave Changes in Patients With Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT)

“…Similarly, though an inverted U-wave is considered as a hallmark for the presence of myocardial ischemia or hypertrophy, [6][7][8][9][10] a prompt change after a pause has not been previously reported as found in the present study. The mechanism and the significance of such peculiar changes in the U-wave need to be determined.…”

“…[1][2][3][4] There are clinical settings in which abnormal U-waves can be observed: prominent U-waves in hypokalemia, 5) inverted U-waves in myocardial ischemia, [6][7][8] ventricular hypertrophy or dilatation, 9,10) or alteration in the amplitude in ischemic heart disease or in idiopathic ventricular tachycardia.…”

“…Changes in the amplitude of the U-wave might be observed in some patients with ischemic heart disease during exercise stress testing 6,8) or following a pause after premature ventricular contraction in patients with idiopathic ventricular tachycardia 11) or long QT syndrome, 27) but alternans of the U-wave has not been reported. Similarly, though an inverted U-wave is considered as a hallmark for the presence of myocardial ischemia or hypertrophy, [6][7][8][9][10] a prompt change after a pause has not been previously reported as found in the present study.…”

Appearance of Electrocardiographic Initial U‐Wave Inversion Dependent on Pressure‐Induced Early Diastolic Impairment in Patients with Hypertension

“…17 Terminal U inversion has also been reported to appear frequently during exercise-induced angina in patients having total or subtotal occlusion of LAD in association with welldeveloped collateral circulation to the artery. 6,18,19 The appearance of terminal U inversion, therefore, may be related to the regional marked heterogeneity of transient severe transmural ischemia with a high grade of ischemia in the subendocardium and low grade of ischemia in the subepicardium in the anteroseptal area, leading to severe regional heterogeneity or inversion of repolarization.…”

The negative U wave: A pathogenetic enigma but a useful, often overlooked bedside diagnostic and prognostic clue in ischemic heart disease

“…44 All these findings point to a mechanical influence, namely stretch, in the nU genesis. 9,13,16,27 The transitory inducibility of the nU by acute supply ischemia during PTCA offers an experimental model in humans that may help explain its pathogenesis. 18,19,21 During the ischemic cascade, the mechanical response precedes typical ST-T changes; similarly, during PTCA-induced ischemia, the nU precedes ST-T changes.…”