Prediction of cardiac events in patients with reduced left ventricular ejection fraction with dobutamine cardiovascular magnetic resonance assessment of wall motion score index.
OBJECTIVE
The purpose of this study was to assess the utility of dobutamine cardiovascular magnetic resonance (DCMR) results for predicting cardiac events in individuals with reduced left ventricular ejection fraction (LVEF).


BACKGROUND
It is unknown whether DCMR results identify a poor cardiac prognosis when the resting LVEF is moderately to severely reduced.


METHODS
Two hundred consecutive patients ages 30 to 88 (average 64) years with an LVEF <or=55% that were poorly suited for stress echocardiography underwent DCMR in which left ventricular wall motion score index (WMSI), defined as the average wall motion of the number of segments scored, was assessed at rest, during low-dose, and after peak intravenous infusion of dobutamine/atropine. All participants were followed for an average of 5 years after DCMR to ascertain the post-testing occurrence of cardiac death, myocardial infarction (MI), and unstable angina or congestive heart failure warranting hospital stay.


RESULTS
After accounting for risk factors associated with coronary arteriosclerosis and MI, a stress-induced increase in WMSI during DCMR was associated with future cardiac events (p < 0.001). A DCMR stress-induced change in WMSI added significantly to predicting future cardiac events (p = 0.003), after accounting for resting LVEF, but this predictive value was confined primarily to those with an LVEF >40%.


CONCLUSIONS
In individuals with mild to moderate reductions in LVEF (40% to 55%), dobutamine-induced increases in WMSI forecast MI and cardiac death to a greater extent than an assessment of resting LVEF. In those with an LVEF <40%, a dobutamine-induced increase in WMSI does not predict MI and cardiac death beyond the assessment of resting LVEF.
Dall'Armellina
Erica
E
Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1045, USA.
Morgan
Timothy M
TM
Mandapaka
Sangeeta
S
Ntim
William
W
Carr
J Jeffrey
JJ
Hamilton
Craig A
CA
Hoyle
John
J
Clark
Hollins
H
Clark
Paige
P
Link
Kerry M
KM
Case
Doug
D
Hundley
W Gregory
WG
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000789:Angina, Unstable / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D025401:Echocardiography, Stress; D005260:Female; D006352:Heart Ventricles / Q000187:drug effects / Q000503:physiopathology; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000000981:diagnostic imaging; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D013318:Stroke Volume / Q000187:drug effects