DIPYRIDAMOLE TL-201 SCINTIGRAPHY FOR EARLY RISK STRATIFICATION OF PATIENTS AFTER UNCOMPLICATED MYOCARDIAL-INFARCTION

Objective-To determine the safety and prognostic value of dipyridamole thallium-201 scintigraphy performed in patients within three to five days of acute myocardial infarction, including those receiving thrombo lytic treatment. Design-A prospective study of dipyridamole thallium-2 01 scintigraphy in patients early after acute myocardial infarction. S etting-University hospital. Patients-200 patients who were clinically uncomplicated at day 3 after infarction, 92 (46%) of whom had received thrombolysis. Main outcome measures-Incidence of cardiac death, non-f atal reinfarction, readmission to hospital for unstable angina, or non -elective revascularisation procedure within six months' follow up. Re sults-No patient had a serious complication from the dipyridamole stud y. At six month follow up, 55 patients (28%) had suffered a defined ca rdiac event. Patients who received thrombolysis had the same extent of thallium-201 redistribution and the same occurrence of subsequent car diac events as those not receiving thrombolysis. Patients who subseque ntly had an event had more myocardial segments showing thallium-201 re distribution than event free patients: 2.7 (SD 1.9) v 1.2 (1.4), respe ctively (p < 0.001). Among all clinical and scintigraphic variables, m ultivariate analysis identified the extent of thallium-201 redistribut ion as the only independent predictor of outcome (p < 0.001). Among 63 patients (32%) of the study cohort who showed more than two myocardia l segments with thallium-201 redistribution, the adjusted risk ratio f or a cardiac event was 7.5 (95% confidence interval 2.9 to 19.1) compa red with patients without any redistribution. Conclusions-Dipyridamole thallium-201 scintigraphy can be performed safely within a few days o f the event in patients with uncomplicated myocardial infarction, incl uding those who received thrombolysis, and can identify a subgroup of patients at high risk of future ischaemic events.