Thallium-201 myocardial SPET in patients with collagen disease

We analysed stress Tl-201 myocardial single photon emission tomography (SPET) in collagen disease patients to evaluate abnormal uptake patterns and their clinical significance in the assessment of the cardiac status of these patients. The main purpose of the study was to evaluate the clinical significance of reverse redistribution. Twenty-two collagen disease patients (13 with progressive systemic sclerosis (PSS) and nine with systemic lupus erythematosus (SLE)) were examined by Tl-201 myocardial SPET with exercise (n = 9) or dipyridamole stress (n = 13). For quantitative analysis, each Tl-201. SPET polar map was divided into 17 segments, and the Tl-201 uptake pattern of each segment was classified into four types. Eighteen (82%) of the patients showed abnormal findings on Tl-201 SPET. Of the 374 segments analysed, 295 (79%) were classified as normal, 16 (4%) as reverse redistribution, 49 (13%) as reversible defect and 14 (4%) as fixed defect. Patients were divided into two groups: those with cardiac abnormalities on conventional testing (Group A, n=10) and those without (Group B, n=12). The incidences of fixed defect, reversible defect and reverse redistribution were significantly higher (P<0.01, P<0.0005, P<0.05, respectively) in Group A than in Group B. Nine (90%) of the patients in Group A and nine (75%) in Group B showed abnormal findings. No significant difference was found between the PSS and SLE patients in the incidence of the individual uptake patterns. Stress Tl-201 myocardial SPET appears to be an effective method of evaluating a wide spectrum of myocardial involvement in collagen disease patients and in assessing their clinical cardiac status. Reverse redistribution is found to be a significant finding in collagen disease patients. ((C) 2000 Lippincott Williams & Wilkins).