Prognostic Value Of Thallium 201 Myocardial Scintigraphy With Dipyridamole

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 ischaernic 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.