[Prognostic value of thallium 201 myocardial scintigraphy with dipyridamole before peripheral arterial surgery]

The evaluation of patients who are candidates for peripheral arterial surgery is difficult. The aim of this study was to show that dipyridamole stress scintigraphy could be a prognostic aid for patient selection. Between 1991 and 2000, 275 patients underwent dipyridamole stress myocardial scintigraphy before peripheral arterial surgery of the lower limbs (49%), the aortic (33%) or carotid arteries (18%). A perfusion defect was observed in 145 patients suggesting myocardial ischaemia in 79 cases and myocardial infarction in 66 cases. Twenty-seven of the 79 ischaemic patients underwent a preoperative coronary revascularisation. The operative adverse coronary events (5%) were: 7 non-fatal myocardial infarctions and 7 acute coronary syndromes. The 79 ischaemic patients had a higher risk of adverse coronary events: 11% (ischaemia) versus 3% (no ischaemia) (p < 0.01). Myocardial scintigraphy allowed stratification of patients with an intermediate risk of Eagle's score into high coronary risk (15%, ischaemia) or low coronary risk (2%, no ischaemia) (p < 0.01). The extent of the ischaemia was associated with a higher risk of adverse coronary events: 4 zones (20%) versus 1 zone (5%) (p = 0.02). Preoperative coronary revascularisation tended to reduce the risk of adverse coronary events from 15% to 4% (p = NS). Myocardial ischaemia (p < 0.0001) and left bundle branch block (p = 0.002) were the two predictive factors of an adverse operative coronary event. Thallium-dipyridamole myocardial scintigraphy with a high negative predictive value (97%) is a useful tool for the identification of high risk patients for whom an aggressive preoperative therapeutic strategy may be beneficial.