[Diagnosis and prognosis of elderly patients with coronary artery disease: assessment with dipyridamole thallium imaging].

Noninvasive evaluation of coronary artery disease is difficult in elderly patients because of their limited exercise-capacity. The diagnostic and prognostic value of dipyridamole perfusion scintigraphy was assessed in 147 patients aged 65 years and older. All patients underwent coronary angiography. Initially, 32 patients had percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass grafting (CABG). The other 115 patients were first treated medically and followed for a mean of 29 +/- 22 months. Nine patients (7.9%) had cardiac events including cardiac death and coronary intervention (PTCA or CABG) during the follow-up. Dipyridamole perfusion scintigraphy was performed safely in all patients, whereas treadmill exercise testing could not be adequately performed in 24 patients, 18 of whom had multivessel disease. Multiple regression analysis showed that: fixed defect and reversible defect were powerful detectors of coronary lesions (p = 0.0001, p = 0.0027, respectively), all patients with fixed disease and 94% of patients with only reversible defect had significant coronary lesion; Diffuse slow washout and ST depression were statistically significant for detecting multivessel coronary lesions in patients with fixed disease (p = 0.0001, p = 0.017, respectively), the sensitivity and specificity of diffuse slow washout and/or ST depression for detecting multivessel coronary lesions ware 85% and 74%, respectively, and ST depression was statistically significant for detecting multivessel coronary lesions (p = 0.0002) in patients with only reversible defect, the sensitivity and specificity of ST depression were 88% and 64%, respectively. Cox survival analysis identified diffuse slow washout as the best predictor of future cardiac events among the scintigraphic variables.(ABSTRACT TRUNCATED AT 250 WORDS)