Copyright © 1993 by the European Society of Cardiology.
© 1993 The Europen Society of Cardiology
Influence of left ventricular filling profile during preceding control beats on the occurrence of pulse deficit caused by ventricular premature contractions
*First Department of Internal Medicine, Faculty of Medicine, Kagoshima University Japan
Section of Cardiology, Kagoshima Municipal Hospital Japan
Received 25 November 1992; revised 3 March 1993; .
Correspondence Hiromitsu Tanaka, MD. The First Department of Internal Medicine, Faculty of Medicine, Kagoshima University, Sakuragaoka 8-35-1, Kagoshima City, 890, Japan
Abstract
This study was designed to investigate whether the left ventricular filling profile during preceding control beats significantly affects the pulse deficit caused by ventricular premature contractions (VPCs). The study group consisted of 18 patients (10 men, eight women, 15–85 years old) who underwent electrophysiological catheterization because of sinus bradycardia. Using a temporary pacing lead inserted in the right ventricular apex, isolated VPCs with various coupling intervals were produced by electrical stimulation of the right ventricle. During the production of the VPCs, the mitral filling flow velocity using pulsed wave Doppler echocardiography, the femoral arterial pressure curve and the electrocardiogram were simultaneously recorded. The right ventricle was siimulated 800, 750, 700, 650, 600, 550, 500, 450 and 400 ms after the triggered control beat QRS complex. Pulse pressures during VPCs gradually decreased in relation to the shortening of the extra-systolic beat coupling interval. The longest coupling interval for each subject, which caused complete abolition of the pressure pulse during the VPC, was defined as the pulse deficit coupling interval. The early to late diastolic velocity–time integral ratio (Ei/Ai ratio) of the mitral filling flow velocity during the control beats which precede the VPC was obtained as an index expressing the left ventricular filling profile. The Ei/Ai ratio of the mitral filling flow velocity ranged from 0.7 to 4.5 (1.8 ± 1.0). The pulse deficit coupling interval ranged from 440 to 640 ms (510 ± 60 ms). A significant negative correlation was observed between the Ei/Ai ratio and the pulse deficit coupling interval (r = –0.69, P<0.01). A significant positive correlation was also observed between the age and the pulse deficit coupling interval (r = 0.63, P<0.01). The findings are consistent with the concept that pulse deficit by VPCs may easily occur in patients with reduced left ventricular filling during the early diastole.
Key Words: Doppler echocardiography • ventricular premature contraction