Comparison of Dobutamine Stress Echocardio-graphy with Myocardial Perfusion Scintigraphy for Detecting Coronary Artery Disease in Patients with Left Bundle-Branch Block

The aim of this study is to compare the efficacy of dobutamine stress echocardiography (DSE) and exercise myocardial perfusion scintigraphy (MPS) for the noninvasive identification of coronary artery disease (CAD) in patients with left bıındle-branch block (LBBB). Thirty-one patients with complete, permanent LBBB (19 men, 12 women, mean age: 59±9) referred with different complaints (chest pain, shortness of breath, palpitation ete.) were evaluated prospectively. Patients with previous myocardial infarction, known to have valvular disease or cardiomyopathy were excluded. DSE, exercise MPS and coronary angiography were performed to all patients within 6 months by examiners who were blinded to other test results. Stress induced wall thickening impairment or worsening of wall motion in a normal or hypokinetic region at rest were regarded as i sche ıni a in DSE. The ischemic region was localized according to the coronary aıtery territo ı-ies. Exercise MPS was perfoı-med with Tc99m tetrofosmin in 20 patients and TI-201 in ll patients by either planar ()r SPECT methods. A reversible defect, more than 15%, at rest was considered as ischemia. The results were compared with the existence of >50% luminal diameter coronary stenosis in the angiographic examination. Eight patients (22%) had CAD in the angiographic study. Others had normal coronary arteries. Two of the normal coronary aıtery group had diffuse left ventı-icular dysfunction and one had segmenter wall motion abnormality. Sensitivity, specificity and diagnostic accuracy were 88%, 91%, and 90% respectively for DSE. Sensitivity, specificity and diagnostic accuracy were 75%, 96%, and 90% respectively forMPS. We conclude that both DSE and exercise MPS are accurate tests for the noninvasive identifıcation of CAD in LBBB patients.