Effects of revascularisation and contractile reserve on left ventricular remodelling in patients with impaired left ventricular function.
OBJECTIVE
We sought to define the influence of revascularisation and contractile reserve on left ventricular (LV) remodelling in patients with LV dysfunction after myocardial infarction. Revascularisation of viable myocardium is associated with improved regional function, but the effect on remodelling is undefined.


METHODS
We studied 70 patients with coronary artery disease and LV dysfunction, 31 of whom underwent revascularisation. A standard dobutamine stress echocardiogram (DbE) was carried out. All patients underwent standard medical treatment; the decision to revascularise was made clinically, independent of this study. LV volumes and ejection fraction were measured by 3D echocardiography at baseline and after an average of 40 weeks.


RESULTS
There was no significant difference in baseline ejection fraction or volumes between patients who underwent revascularisation and the remainder. Compared to medically treated patients, revascularised patients had significant improvements in ejection fraction and end-systolic volume in follow-up. The impact of baseline variables on remodelling was assessed by dividing patients into tertiles of LV ejection fraction and volumes. Revascularised patients in the lowest tertile of ejection fraction at baseline (<38%) had a significant improvement in end-systolic volume and ejection fraction, larger than obtained in medically treated patients with low ejection fraction. Revascularised patients with an ejection fraction >38% did not show significant improvement in volumes compared to baseline. Revascularised patients in the largest tertiles of end-systolic (>88 ml) or end-diastolic volume (>149 ml) at baseline had a significant improvement in end-systolic volume.


CONCLUSIONS
Remodeling appears to occur independent of the presence of regional contractile reserve but does correlate with the volume response to low-dose dobutamine.
Khoury
Vincent K
VK
Department of Medicine, University of Queensland, Princess Alexandra Hospital, Ipswich Road, Brisbane, Queensland 4102, Australia.
Haluska
Brian
B
Fathi
Robert
R
Marwick
Thomas H
TH
D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D004280:Dobutamine; D004452:Echocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D009204:Myocardial Revascularization; D018709:Statistics, Nonparametric; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D020257:Ventricular Remodeling / Q000502:physiology*
D004280:Dobutamine