Dobutamine-induced augmentation of left ventricular ejection fraction predicts survival of heart failure patients with severe non-ischaemic cardiomyopathy.
OBJECTIVE
The prognosis of patients with severe non-ischaemic dilated cardiomyopathy is variable. The predictive value of currently utilized tests is suboptimal. The purpose of this study was to determine the prognostic value of dobutamine-induced augmentation of left ventricular ejection fraction in patients with non-ischaemic dilated cardiomyopathy.


RESULTS
Sixty-two patients with left ventricular ejection fraction < or =0.30 underwent exercise testing with gas exchange analysis and assessment of left ventricular ejection fraction at rest and after a 10-min intravenous infusion of dobutamine at 10 microg x kg(-1) x min(-1), using equilibrium radionuclide ventriculography. Age was 48+/-11 years, 32% females, functional class 2.6+/-0.6, resting left ventricular ejection fraction 0.20+/-0.06, and peak exercise oxygen consumption (mVO2) 19+/-6 ml x kg(-1) x min(-1). Mean dobutamine-induced augmentation of left ventricular ejection fraction (DeltaLVEF) was 0.09+/-0.06 (median 0.08, range -0.03 to 0.26). Follow-up was 25+/-15 months during which there were 12 deaths and five transplantations. Patients were divided into two groups based on median DeltaLVEF. The transplant-free survival was better in the group with higher DeltaLVEF (94% vs 64%, P<0.008). In multivariate analysis incorporating age, gender, duration of chronic heart failure, functional class, right and left ventricular ejection fraction, DeltaLVEF, left ventricular end-diastolic volume index, and mVO2, only DeltaLVEF was predictive of 1-year, 3-year, and overall transplant-free survival (RR 0.09, 0.03, and 0.13;P 0.03, 0.09, and 0.08 respectively). The linear correlation between DeltaLVEF and mVO2(r=0.3) and between DeltaLVEF and left ventricular ejection fraction (r=0.5) was weak.


CONCLUSIONS
Dobutamine-induced augmentation of left ventricular ejection fraction is a strong prognostic variable, independent of exercise capacity and resting ventriculographic variables, in severe non-ischaemic systolic dysfunctional heart failure.
Ramahi
T M
TM
Section of Cardiovascular Medicine, Yale School of Medicine, New Haven, CT, USA.
Longo
M D
MD
Cadariu
A R
AR
Rohlfs
K
K
Slade
M
M
Carolan
S
S
Vallejo
E
E
Wackers
F J
FJ
D000328:Adult; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging / Q000401:mortality* / Q000503:physiopathology*; D004280:Dobutamine; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000401:mortality* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D015635:Radionuclide Ventriculography; D013318:Stroke Volume / Q000187:drug effects* / Q000502:physiology; D015996:Survival Rate; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000401:mortality* / Q000503:physiopathology*; D016277:Ventricular Function, Left / Q000187:drug effects* / Q000502:physiology
D004280:Dobutamine