Thallium-201 myocardial perfusion imaging in patients with systemic lupus erythematosus

The cardiovascular system is frequently affected in systemic lupus erythematosus (SLE). The observation of clinical manifestations related to the presence of coronary artery disease has not been frequently documented in young SLE patients. In these patients, the presence of inflammatory or thrombotic vascular lesions is often documented by anatomo-histological studies in the absence of previous clinical manifestations. The purpose of this study was to evaluate the presence of myocardial perfusion defects in SLE patients. The study was carried out in 15 patients without clinical signs of myocardial ischemia, 1 male and 14 females, 24 to 64 years old, with a mean SLE duration of 10.2 +/- 7.5 years. All the patients had normal blood pressure; electrocardiogram and Doppler-echocardiographic analysis showed values in the normal range. All the patients underwent thallium-201 exercise stress imaging repeated 3 hours later at rest, with tomographic SPECT analysis. Exercise test was carried out until submaximal load, without induction of ST segment alterations or symptoms. Scintigraphic scan showed normal thallium-201 SPECT imaging in 11/15 patients, while the other 4 patients had a slight perfusion defect, 3 of them in the inferior segment, in 2 non reversible and in 1 reversible; 1 patient had a non reversible defect in the septal segment. These slight perfusion defects, prevalently non reversible, may sometimes be a false positive imaging. Our results are in contrast with the literature observations concerning the frequent incidence of thallium-201 perfusion defects in SLE patients. In young asymptomatic SLE patients, our study does not report very important data indicating myocardial ischemia and suggesting the presence of significant coronary obstruction or vasculitis.