Despite the cardioprotective effect of rapid coronary reperfusion, the effects of spontaneous recanalization on myocardial viability and metabolism are unknown. We studied whether
preinfarction angina affords cardioprotection when spontaneous coronary reperfusion occurred in acute
infarct patients. Myocardial tomographies with
thallium and I-123-labeled-beta-methyl-p-iodophenyl
penta-
decanoic acid (
BMIPP) were performed in 27 acute
myocardial infarct patients treated medically: 15 patients had preexisting angina before
infarction (group A) and 12 did not (group B).
Thallium and
BMIPP abnormalities and regional function were quantified by a polar map and contrast ventriculography, respectively. There was no significant difference between
thallium and
BMIPP in the severity index in groups A and B (89 +/- 97 vs. 85 +/- 68, 97 +/- 28 vs. 95 +/- 27, respectively), and no significant difference between the groups in the
thallium or
BMIPP severity index. The ratio of the
thallium severity index to that of
BMIPP and the regional wall-motion abnormality index were identical in groups A and B. Both patient groups were divided into 2 subgroups based on the presence or absence of spontaneous coronary reperfusion: subgroups A1 and A2, and subgroups B1 and B2, respectively. There were no significant differences among the 4 subgroups in severity indexes for both tracers, the
thallium/
BMIPP ratio, or the asynergy score. The
BMIPP severity index correlated significantly with that of
thallium in all subgroups, but no significant difference between the regression lines was found. It is therefore unlikely that spontaneous coronary recanalization affords beneficial effects through preservation of myocardial viability in an
ischemia-related zone, suggesting that the cardioprotective effect of
preinfarction angina is a limited phenomenon in patients undergoing rapid coronary reperfusion.