Left ventricular cavity obliteration during dobutamine stress echocardiography in diabetic patients

Abstract

Prevalence of dynamic left ventricular outflow tract obstruction (DLVO) during dobutamine stress-echo (DSE) seems disproportionally high among diabetic patients. We retrospectively identified 212 diabetic (D+) and 212 non diabetic (D-) subjects, who underwent DSE for suspected coronary artery disease (CAD); we evaluated DSE-induced DLVO prevalence and correlates. During DSE, 105 patients in D+ (50%) and 83 in D- group (39%, P = 0.032) developed a DLVO, with similar maximum gradient (94 ± 49 mmHg in D+ vs. 86 ± 49 mmHg in D-, P = NS). D+ and D- patients with DLVO showed reduced LV end-diastolic and end-systolic dimension. Compared with diabetic subjects without DLVO, diabetic patients with DLVO had higher left ventricular (LV) ejection fraction (EF), lower LV mass index; diastolic function was normal in a higher proportion of cases. Non diabetic patients with moderate or severe DLVO had higher LV EF compared with patients without DLVO. At multivariate analysis, in D+ patients, the only independent predictor was a smaller LV end-diastolic diameter (HR 0.779, CI 0.655-0.926, P = 0.005); in D- patients lower age (HR 0.878, CI 0.806-0.957, P = 0.003), higher LV EF (HR 1.087, CI 1.003-1.177, P = 0.042) and lower peak WMSI (HR 0.017, CI 0.001-0.325, P = 0.007) were associated to presence of DLVO. In D+ patients, during a median follow-up of 924 ± 134 days, we observed 11 new cardiac events, only 1 in patients with DLVO (P = 0.0041). DSE-provoked DLVO had a very high prevalence in patients evaluated for suspected CAD, especially among diabetic patients; echocardiographic predictors were a reduced LV dimension in D+ and a preserved systolic function, both at rest and at peak stress, in D- patients.