Acute effects of cardiac resynchronization therapy on left ventricular Doppler indices in patients with congestive heart failure.
BACKGROUND
Patients with heart failure frequently exhibit intraventricular conduction delays, which contribute to asynchronous contraction patterns and impaired hemodynamic performance. Cardiac resynchronization therapy (CRT) with biventricular (BV) and left ventricular (LV) pacing has been shown to improve both hemodynamic and clinical performance. This study investigated the effects of CRT on LV Doppler indices in these patients.


RESULTS
Thirty-two patients with advanced heart failure (New York Heart Association class > or =III, QRS >120 milliseconds, PR interval >150 milliseconds) were studied 4 weeks after implantation of a CRT system. Doppler echocardiography was conducted in 3 separate CRT modes, right ventricular, LV, and BV stimulation at 3 different atrioventricular delays. CRT resulted in significant improvement of Doppler parameters such as filling time (FT, 313 +/- 111 milliseconds at baseline --> 363 +/- 154 milliseconds [BV], P <.05), aortic velocity time integral (AO(VTI) 23.2 +/- 7.4 cm at baseline --> 26.8 +/- 8.8 cm [LV], P <.05), and the myocardial performance index (MPI, 1.21 +/- 0.51 at baseline --> 0.85 +/- 0.34 [BV], P <.05). The most improvement was observed with LV and BV stimulation at short and intermediate atrioventricular delays (80-120 milliseconds), independent of ischemic or idiopathic origin.


CONCLUSIONS
CRT improves hemodynamic performance in patients with heart failure with intraventricular conduction delays. Doppler echocardiography allows noninvasive evaluation of acute CRT effects in patients with heart failure. In particular, FT, AO(VTI), and MPI are useful parameters for noninvasive follow-up and optimization of pacing parameters.
Breithardt
Ole-A
OA
Department of Cardiology, RWTH University of Technology, Aachen, Germany.
Stellbrink
Christoph
C
Franke
Andreas
A
Balta
Osman
O
Diem
Björn H
BH
Bakker
Patricia
P
Sack
Stefan
S
Auricchio
Angelo
A
Pochet
Thierry
T
Salo
Rodney
R
D000704:Analysis of Variance; D001283:Atrioventricular Node / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D002311:Cardiomyopathy, Dilated / Q000150:complications* / Q000000981:diagnostic imaging; D018592:Cross-Over Studies; D015150:Echocardiography, Doppler; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D010138:Pacemaker, Artificial; D016037:Single-Blind Method; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D018497:Ventricular Dysfunction, Right / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*