[Prognostic significance of large perfusion defects on thallium-201 myocardial scintigraphy in dilated cardiomyopathy].

To evaluate the prognostic significance of perfusion abnormalities, particularly large defects, in dilated cardiomyopathy (DCM), we performed thallium-201 myocardial scintigraphy and 24-hour ambulatory ECG monitoring in 27 patients. The abnormal scintigraphic patterns and the presence of ventricular tachycardia (VT) were correlated with causes of death during a follow-up period of 30.0 +/- 19.4 months. Eight patients had large defects (LD), 11 had multiple small defects (MSD), and eight had no defects (NL). The patients with LD had extensive ventricular akinesis in the region of the perfusion defect, significantly elevated LVEDP (LD 20.6 +/- 7.4 mmHg, MSD 15.5 +/- 7.6 mmHg, NL 10.3 +/- 2.3 mmHg: LD vs NL; p less than 0.01, MSD vs NL; p less than 0.05), and reduced ejection fraction (LD 23.9 +/- 9.1%, MSD 32.7 +/- 7.2%, NL 40.3 +/- 7.7%: LD vs MSD; p less than 0.05, MSD vs NL; p less than 0.01). VT was detected in 11 patients; among whom three had LD, six had MSD, and two had no defects. Among seven patients who died during follow-up (five of heart failure, one sudden death, and one non-cardiac death), five had LD and two had MSD. There were no deaths among patients without defects. Among 11 patients with VT, only one died suddenly. In conclusion, large scintigraphic defects correlated well with severe LV dysfunction, and this is an important variable in predicting outcomes in DCM.