Risk stratification and prognostic assessment by myocardial perfusion-gated SPECT in patients with left bundle-branch block and low-intermediate cardiac risk

Objective In high-risk patients with left bundle-branch block (LBBB), functional but not perfusion parameters yield incremental prognostic information. The aim of our study was to evaluate the prognostic value of gated single photon emission computed tomography (SPECT) in low-intermediate risk LBBB patients. Methods One hundred seventy-six subjects underwent stress-rest dual-day protocol 99mTc sestamibi-gated SPECT and were dichotomized in two groups: without LBBB (Group 1, n = 86) and with LBBB (Group 2, n = 90). Patients were followed for 32 ± 18 months. Cox regression multivariate analysis was used to determine which variable was the best predictor of cardiac event. Event-free survival curves were computed by Kaplan–Meier method. Results Myocardial perfusion scintigraphy was abnormal in 32 and 60 patients for Groups 1 and 2, respectively (37 vs. 67 %, p