Abstract 17474: The Morphological Change of Left Ventricular Outflow Tract by Aging

Background: The Area of left ventricular outflow tract (LVOT) is now calculated with LVOT diameter on the assumption that it's shape is a circle. The latest development of three dimensional echocardiography (3DE) can visualize LVOT directly. The morphological change of LVOT by aging is not clear. Methods: we evaluated 50 cases (mean age 61 years, 24 male ) which have normal left ventricular ejection fraction with transthoracic echocardiography. We recorded conventional left ventricular morphology with two dimensional echocardiography and recorded 3DE of parasternal long axis view and analyzed LVOT area (LVOT-A) and long (D1) and short axis (D2) of LVOT diameter at end diastole. Results: LVOT showed elliptical shape and LVOT-A obtained with 3DE was larger than the LVOT-A calculated with LVOT diameter (3.9±0.6cm2 v.s.3.1±0.6cm2;p<0.01). We divided these study population into 2 groups according with age. GroupIwas composed with less than 60 years (mean age 45 years n=21), GroupII was more than 60 years ( mea...