Twenty-four-hour heart rate behavior in patients with impaired left ventricular function due to coronary heart disease.
We performed a 24-hour Holter monitoring study on 45 patients affected by coronary artery disease (CAD) with different degrees of left ventricular impairment, and on 15 controls, in order to observe heart rate (HR) changes. According to the ejection fraction (EF) determined by cardiac angiography, CAD patients were divided into 3 groups of 15 each: the first with EF greater than 0.5; the second with EF between 0.35 and 0.5 and the third with EF less than 0.35. Spontaneous HR variation during 24 h did not differ among controls and CAD patients with normal EF values. On the contrary, with the reduction of ventricular function, CAD patients showed increasingly higher values of HR only during the night. Patients with markedly reduced EF values showed higher values of HR than controls even during some hours of the day. During the night EF and HR showed a good linear correlation with the highest r value at 5 a.m. (r = 0.7, p less than 0.001). Present data show that a reduction in left ventricular performance results in an altered 24-hour HR pattern with a reduced HR slowing at night proportional to the extent of left ventricular dysfunction.
D000328:Adult; D000368:Aged; D003327:Coronary Disease / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D013318:Stroke Volume