Echocardiographic diagnosis of dilatation of the ascending aorta using right parasternal scanning.

With the ultrasound transducer positioned at the second or third right intercostal space, the ascending aorta was visualized in 8 patients in whom dilatation of the ascending aorta had been demonstrated radiographically. The diameter of the ascending aorta by right parasternal scan, with the transducer held perpendicular to the chest wall, measured 4.2-6 cm. The aortic root diameter (at aortic valve level) recorded by conventional left parasternal scan was normal or only slightly increased in 5 cases, but in 3 others it approached the value obtained by right parasternal scan. Aortography performed in 3 patients demonstrated marked dilatation of the ascending aorta.