Usefulness of low-dose dobutamine stress echocardiography for evaluating reversibility of brain death-induced myocardial dysfunction

Many of the myocardial wall motion abnormalities in heart donors are revers ible after transplantation, indicating that the presence of wall motion abn ormalities should not automatically lead to the exclusion of donor hearts. The present study observes the natural course of brain death-induced myocar dial dysfunction, and investigates whether low-dose dobutamine stress echoc ardiography could identify reversible myocardial dysfunction in brain-dead patients. We prospectively measured the serial changes of left ventricular fractional shortening (FS) using echocardiography and cardiac troponin T fr om admission to the time of cardiac standstill in 30 brain-dead patients. P atients were divided into 2 groups according to FS at the time of brain dea th; group I (FS greater than or equal to 30%) and group II (FS <30%). Dobut amine stress echocardiography was performed in group II. Twenty-three patie nts were in group I and 7 patients were in group II. Four patients among 7 patients in group II showed dobutamine-nonresponsive wall motion (group IIa ) and the remaining 3 patients showed dobutamine-responsive wall motion (gr oup IIb), Troponin T at the time of brain death was markedly higher in grou p IIa than in groups I and IIb (5.13 +/- 3.79 vs 0.23 +/- 0.20, 0.22 +/- 0. 16 ng/ml, p <0.0001, respectively). FS remained normal and troponin T was n ot increased until cardiac standstill in group I. FS remained decreased and troponin T remained elevated until cardiac standstill in group IIa, wherea s FS became normal at 7 days after brain death with no change in troponin T in group IIb. Thus, some brain death-induced myocardial dysfunction is rev ersible and low-dose dobutamine stress echocardiography may identify revers ible myocardial dysfunction. (C) 1999 by Excerpta Medica, Inc.