[Hemodynamic benefits of sequential atrioventricular pacing].
The purpose of this study was to evaluate the hemodynamic benefits of atrioventricular (A-V) sequential pacing. 30 pts implanted with DDD pacemakers underwent M-mode, B-mode and Doppler echocardiography. In each patient, left ventricular (LV) stroke volume was assessed by measuring the time-velocity integral of mitral inflow in the following modes and rates: VOO at 70 ppm or at the minimum stimulation rate and at 120 ppm; DOO at the same rates with different A-V delay (100, 150, 200, 250 and, whenever possible, 300 msec). The increase in stroke volume obtained with dual chamber pacing at the optimal A-V delay was 45 +/- 25% at 75 ppm and 29 +/- 14% at 120 ppm (p less than 0.05 75 vs 120 ppm). This increase was significantly higher in pts with than in pts without LV hypertrophy (respectively: 51.9 +/- 20.4 vs 36.9 +/- 20.8% at 75 ppm, p less than 0.05 and 33 +/- 13.4 vs 25.4 +/- 14.5% at 120 ppm, p = 0.08). Concerning the A-V delay, we noted that at 75 ppm stroke volume was significantly higher in DOO than in VOO with any A-V delay ranging +/- 100 msec from the optimal one; at 120 ppm the hemodynamic benefit of DOO pacing was observed only when the programmed A-V delay was the optimal one or very near to it. In conclusion, atrio-ventricular sequential pacing allows a significant increase in LV stroke volume over single chamber ventricular pacing both at 75 and 120 ppm. Programming the optimal A-V delay is absolutely necessary to obtain this hemodynamic benefit at the higher stimulation rate.
Ghio
S
S
Divisione di Cardiologia, Policlinico S. Matteo, Pavia.
Marinoni
G
G
Broglia
P
P
Eleuteri
E
E
Barba
F
F
Bargiggia
G
G
Bosatra
C
C
Pantusa
V
V
Perotti
R
R
Montemartini
C
C
D000368:Aged; D004452:Echocardiography; D015150:Echocardiography, Doppler; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D013318:Stroke Volume
Beneficio emodinamico della stimolazione sequenziale atrio-ventricolare.