Dipyridamole thallium-201 scintigraphy in patients with arteriosclerosis obliterans. Increased accuracy in identifying cardiac risk.

Forty-eight preselected patients (pts) with arteriosclerosis obliterans were investigated by dipyridamole thallium scintigraphy (DTS). No correlation was found between the distribution of positive or negative exercise ECG testing (ExECG) and isotopic risk-scores (P > 0.1 in the chi-square test). We assessed cardiac ischaemia in 12 pts with insufficient ExECG. Although only 2 pts had documented previous myocardial infarction, 20 pts exhibited irreversible perfusion defect. Silent reversible or irreversible ischaemia was identified in 12 pts (25%). Seven pts would not have been diagnosed to have coronary artery disease (CAD) even by ExECG. In conclusion, DTS was found very useful in these cases. We support a stepwise cardiac risk stratification before major vascular surgery.