[Postoperative changes in perfusion scintigraphic picture in patients with previous myocardial infarct].
In 44 patients with previous MI who underwent CABG, we studied the effect of surgical reperfusion by comparing the different patterns of Thallium uptake after effort or dipyridamole test. For each patient, 9 myocardial segments were classified either normal or abnormal for reversible or irreversible uptake defect, both before and after surgery. CABG (complete in 77% of patients) reduced the incidence of angina (16% vs 77% pre-CABG, p less than 0.001) and of significant (greater than 1 mm) ST-segment depression during the test (20% vs 78%, p less than 0.001). Of 235/496 abnormal segments, 111 (47%) normalised or improved after CABG while an impairment was observed in 34/277 (12%) normal segments or with reversible defect at pre-CABG scan (p less than 0.001). Reversible defects showed a far better outcome relative to irreversible defects: an improvement was achieved in 68% of the former instances, vs only in 27% of the latter (p less than 0.001). Among the 264 myocardial segments which can be ascribed consistently to the territory of some particular coronary vessel, a significantly greater incidence of post-CABG improvement was found in revascularized segments (60/195 vs 5/69, p less than 0.0005). On the contrary it was not possible to correlate the surgery outcome with the presence of ECG Q-waves in the segment. Thus the presence of reversible Thallium defects in post MI patients predicts the improvement of regional perfusion pattern after CABG, regardless of the presence of Q waves.(ABSTRACT TRUNCATED AT 250 WORDS)
Galli
M
M
Divisione di Cardiologia, Fondazione Clinica del Lavoro, Centro Medico di Riabilitazione, Veruno, Novara.
Bencivelli
W
W
Pardo
N F
NF
Tavazzi
L
L
D000368:Aged; D001026:Coronary Artery Bypass; D003331:Coronary Vessels / Q000000981:diagnostic imaging; D005069:Evaluation Studies as Topic; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000601:surgery*; D015425:Myocardial Reperfusion; D011379:Prognosis; D011877:Radionuclide Imaging
Evoluzione post-chirurgica del quadro scintigrafico perfusorio in pazienti con pregresso infarto miocardico.