Open AccessChronotropic incompetence in exercise testing
Author(s) -
Chin C.F.,
Messenger J. C.,
Greenberg P. S.,
Ellestad M. H.
Publication year - 1979
Publication title -
clinical cardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.263
H-Index - 72
eISSN - 1932-8737
pISSN - 0160-9289
DOI - 10.1002/clc.4960020103
Subject(s) - chronotropic , medicine , cardiology , heart rate , stress testing (software) , st depression , bruce protocol , heart failure , depression (economics) , st segment , blood pressure , myocardial infarction , computer science , economics , macroeconomics , programming language
Abstract Patients with chronotropic incompetence, defined as a failure of the heart rate response to exercise to rise to within two standard deviations of the expected increase with exercise, were studied and compared to patients with known coronary disease by angiogram with and without ST segment depression. 72 % of the patients with chronotropic incompetence but without ST depression had significant coronary heart disease. The demonstration of chronotropic incompetence in exercise testing has important predictive implications and should be looked upon as carefully as ST segment changes. There was no evidence of SA node ischemia in these patients. Intrinsic heart rate measurements done in this study suggest autonomic dysfunction as a possible pathophysiologic mechanism for chronotropic imcompetence. The heart rate response to exercise may be a useful predictor of the presence and severity of coronary disease. Therefore, a predicted heart rate response with standard deviation for age and sex should be included as part of the stress test protocol.