Tissue Doppler imaging predicts improved systolic performance and reversed left ventricular remodeling during long-term cardiac resynchronization therapy.
OBJECTIVE
We sought to evaluate the long-term impact of cardiac resynchronization therapy (CRT) on left ventricular (LV) performance and remodeling using three-dimensional echocardiography and tissue Doppler imaging (TDI).


BACKGROUND
Three-dimensional echocardiography and TDI allow rapid and accurate evaluation of LV volumes and performance.


METHODS
Twenty-five consecutive patients with severe heart failure and bundle branch block who underwent biventricular pacemaker implantation were included. Before and after implantation of the pacemaker, three-dimensional echocardiography and TDI were performed. These examinations were repeated at outpatient visits every six months.


RESULTS
Five patients (20%) died during one-year follow-up. In the remaining 20 patients, significant reductions in LV end-diastolic volume and LV end-systolic volume of 9.6 +/- 14% and 16.5 +/- 15%, respectively (p < 0.01), could be demonstrated during long-term follow-up. Accordingly, LV ejection fraction increased by 21.7 +/- 18% (p < 0.01). According to a newly developed TDI technique-tissue tracking-all regional myocardial segments improved their longitudinal systolic shortening (p < 0.01). The extent of the LV base displaying delayed longitudinal contraction, as detected by TDI before pacemaker implantation, predicted long-term efficacy of CRT. The QRS duration failed to predict resynchronization efficacy.


CONCLUSIONS
Cardiac resynchronization significantly improved LV function and reversed LV remodeling during long-term follow-up. Patients likely to benefit from CRT can be identified by TDI before implantation of a biventricular pacemaker.
Søgaard
Peter
P
Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark. psogaard@dadlnet.dk
Egeblad
Henrik
H
Kim
W Yong
WY
Jensen
Henrik K
HK
Pedersen
Anders K
AK
Kristensen
Bent Ø
BØ
Mortensen
Peter T
PT
D002037:Bundle-Branch Block / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D018618:Echocardiography, Doppler, Color; D019560:Echocardiography, Three-Dimensional; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D011379:Prognosis; D013599:Systole / Q000502:physiology*; D020257:Ventricular Remodeling