Effect of benazepril on heart rate turbulence in patients with dilated cardiomyopathy.
1. Heart rate (HR) turbulence describes short-term sinus rhythmic fluctuation after a single premature ventricular beat. Turbulence onset (TO) and turbulence slope (TS) are two essential parameters in HR turbulence. Turbulence onset and TS have been used to evaluate cardiac autonomic nerve function. 2. In the present study, we measured the HR turbulence in dilated cardiomyopathy (DCM) and determined the possible role of benazepril, an angiotensin-converting enzyme inhibitor (ACEI), on these parameters. There were three groups: control, DCM and DCM treated with benazepril. The control group consisted of normal subjects with PVB, but no structural heart disease. Ambulatory electrocardiogram, blood pressure and echocardiography were analysed. 3. There was an increase in TO and a decrease in TS in DCM patients. Benazepril treatment (10 mg/day, p.o.) reduced those changes. There were no significant differences in blood pressure and left ventricular ejection fraction (LVEF) between DCM patients and DCM patients treated with benazepril. 4. Linear regression analysis showed that TO was negatively correlated with LVEF, whereas TS was positively correlated with LVEF, in the DCM group. After benazepril treatment, the correlations between TO and TS and LVEF disappeared. 5. It is concluded that the TO and TS of HR turbulence are altered in patients with DCM. These alterations indicate a dysfunction of the autonomic control of cardiac electrophysiology in DCM patients. Although TO and TS are correlated with LVEF in DCM patients, the effect of benazepril in improving HR turbulence parameters is not a result of its action on heart function, which suggests a new beneficial effect of ACEI in the treatment of DCM patients.
Zhong
Jiang-Hua
JH
Department of Cardiology, Affiliated Hospital of Hainan Medical College, Haikou, Hainan, China.
Chen
Xiao-Pan
XP
Zeng
Chun-Fang
CF
Yun
Mei-Ling
ML
Yang
Xin-Wei
XW
Chen
Yan-Fang
YF
Yao
Zhen
Z
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D001341:Autonomic Nervous System / Q000187:drug effects / Q000503:physiopathology; D001552:Benzazepines / Q000008:administration & dosage / Q000627:therapeutic use*; D001794:Blood Pressure; D002311:Cardiomyopathy, Dilated / Q000150:complications* / Q000188:drug therapy / Q000503:physiopathology; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D012084:Renin-Angiotensin System / Q000187:drug effects; D013318:Stroke Volume / Q000187:drug effects; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000187:drug effects; D018879:Ventricular Premature Complexes / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology
D000806:Angiotensin-Converting Enzyme Inhibitors; D001552:Benzazepines; C044946:benazepril