Comparison of circadian rhythm characteristics of blood pressure and heart rate in patients before and after elective coronary artery bypass surgery.
Coronary artery bypass grafting surgery (CABGS) is done to reperfuse the ischemic myocardium of coronary disease patients. This study was designed to analyze the circadian rhythm characteristics of blood pressure (BP) and heart rate (HR) of patients before and after CABGS. Fifty-one patients undergoing elective CABGS were studied; 21 patients received one, 12 two and 18 three or more grafts. BP was monitored for 24h before and after CABGS while patients were recumbent in the hospital. Systolic (S) and diastolic (D) BP and HR were assessed every 30 min. Of the 51 patients, 37 (73%) had nondipper 24h BP patterns (nocturnal decline in BP < 10% of daytime mean level) in the preoperative baseline assessment. The peak and MESOR (rhythm-adjusted 24h mean) values of the circadian rhythm in SBP, DBP, and pulse pressure (PP) significantly declined following surgery, while HR and rate-pressure product (RPP = SBP x HR) markedly increased. The double amplitude (peak-to-trough variation) of the circadian rhythm in SBP and DBP was significantly reduced postoperatively, and that of the rhythm in HR and RPP significantly increased. The slopes of the morning rise and evening dip in the 24h SBP profile were reduced significantly after bypass grafting. The corresponding slopes of the HR profile, in contrast, were markedly increased.
Department of Pharmacology, Faculty of Medicine, Gazi University, Ankara, Turkey. mtrak@bir.net.tr
Mert
M
Ceyhan
Serdar
S
Günaydin
Cem
C
Yorgancioglu
Yaman
Y
Zorlutuna
Canan
C
Uluoglu
Hakan
H
Zengil
D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D001026:Coronary Artery Bypass; D003971:Diastole; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000503:physiopathology / Q000601:surgery; D013599:Systole