LEFT VENTRICULAR CONCENTRIC GEOMETRY IS ASSOCIATED WITH DYNAMIC INTRAVENTRICULAR OBSTRUCTION IN PATIENTS WITH HYPERTENSION: DOBUTAMINE STRESS ECHOCARDIOGRAPHY STUDY: PP.8.327

Abstract

Background: We were to evaluate the relation of left ventricular (LV) geometry and dynamic intraventricular obstruction (IVO) during dobutamine stress echocardiography (DSE) which may be responsible for breathlessness in some elderly patients and in selected patients complaining of effort chest discomfort/dyspnea without coronary heart disease in patients with hypertension. Methods: Prospectively enrolled 38 hypertensive patients (mean age 66.0¡3/4 9.9 years; 32% male) underwent echocardiography at rest, during peak dobutamine infusion, and after sublingual NTG 0.6 mg. Concentric geometry was defined by relative wall thickness (RWT, 2x posterior wall thickness at end diastole/LV end-diastolic dimension) over 0.42. The patients with positive exercise electrocardiography, transmural infarction, significant valvular heart disease, atrial fibrillation, beta-blocker therapy, and induced ischemia during DSE were excluded. The development of an IVO during DSE was defined as a late-peaking intraventricular pressure gradient (IVPG) >30mmHg. Results: The patients with RWT >0.42 (n = 15, concentric group) and with RWT ¡Â0.42 (n = 23, non-concentric group) were not different in terms of age, gender, smoking status, diabetes and used anti-hypertensive drugs. Concentric group had smaller LV cavity and volume, and more increased interventricular septum thickness and higher basal septal thickness than non-concentric group. At rest, during peak dose of dobutamine, and after NTG, IVPG was higher in concentric group. The development of an IVO during DSE was higher in concentric group. Conclusions: LV concentric geometry was associated with the development of an IVO during DSE in patients with hypertension who might be good candidate for beta-blocker therapy.