Coronary artery bypass surgery in heart failure patients with chronic reversible and irreversible myocardial dysfunction: effect on heart rate variability.
It is unknown whether surgical revascularization of viable and chronic reversibly dysfunctional myocardium in patients with heart failure is associated with a favorable effect on the autonomic control of heart rate. We studied 38 coronary artery bypass surgery (CABG) patients with an ejection fraction of 36 +/- 7%. Before CABG, the patients underwent 48-hour ambulatory electrocardiographic monitoring to measure heart rate variability (HRV), echocardiography to assess left ventricular function, and positron emission tomography and low-dose dobutamine echocardiography to assess viability. Six months after CABG, ambulatory electrocardiographic monitoring and echocardiography were repeated to assess HRV and recovery of left ventricular function. In spite of viable myocardium and recovery of left ventricular function following CABG, HRV indices were reduced 6 months postoperatively. A potential prognostic benefit gained by revascularizing patients with viability may occur in spite of deteriorated autonomic control of heart rate.
Wiggers
Henrik
H
Department of Cardiology, Skejby Hospital, Aarhus University Hospital, Aarhus, Denmark. henrikwiggers@dadlnet.dk
Bøtker
Hans Erik
HE
Egeblad
Henrik
H
Christiansen
Evald Høj
EH
Nielsen
Torsten Toftegaard
TT
Mølgaard
Henning
H
D000368:Aged; D009202:Cardiomyopathies / Q000175:diagnosis* / Q000503:physiopathology* / Q000601:surgery; D002908:Chronic Disease; D001026:Coronary Artery Bypass; D025401:Echocardiography, Stress; D004562:Electrocardiography; D005260:Female; D006333:Heart Failure / Q000175:diagnosis* / Q000503:physiopathology* / Q000601:surgery; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011300:Preoperative Care; D020127:Recovery of Function / Q000502:physiology; D013997:Time Factors; D014055:Tomography, Emission-Computed; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000502:physiology