Radionuclide imaging in evaluation of ischemic preconditioning on first infarct size and left ventricular functions in the elderly

Objective To evaluate ischemic preconditioning on first infarct size and left ventricular functions in the elderly. Methods Based on the presence or absence of angina pectoris(AP)within 24 hours before onset of acute myocardial infarction(AMI),53 patients were divided into two groups: AP group(n=25) and non AP group(n=28). The size of infarction was detected by 99m Tc MIBI SPECT myocardial perfusion imaging;the incidence of left ventricular enlargement and dyskinesis as well as the left ventricular ejection fraction(LVEF),peak ejection fraction(PER)and peak filling rate(PFR)were used as major indexes for cardiac function by radionuclide ventriculography. The data of the 2 groups were compared. Results Numbers of infarct segments were 3 2±2 6 and 5 6±2 6 in AP group and non AP group respectively( P 0 01) Incidence of left ventricular enlargement and dyskinesis were 12 0%(n=3) and 39 3%(n=11) respectively ( P 0 05). LVEF was (49 3±8 6)% and (41 8±11 4)%,PFR was (2 1±0 4) and (1 6±0 6) edc/s in AP and non AP groups respectively( P 0 05 or P 0 01). Conclusions Our findings suggest that ischemic preconditioning by preinfarction angina pectoris within a short period before AMI is effective for protection of left ventricular functions and reduction of infarct segment size in the aged patients with first AMI.