Potential applications of intracardiac echocardiography in the assessment of the aortic valve from the right ventricular outflow tract

Intracardiac echocardiography (ICE) is a developing technology and a promis ing method for visualizing intracardiac structures. However, its applicatio ns are currently limited to guidance during mitral valvuloplasty, catheter ablation, or electrophysiologic examination. The goal of this study was to observe the aortic valve, measure the annular diameter of the valve by ICE through a right-sided approach, and compare the results by ICE with those b y transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE). We studied 18 patients (9 men, 9 women, aged 19 to 72 years) with va rious heart diseases, including 15 patients with mitral or aortic valvular disease. An imaging catheter was advanced through a long sheath into the ou tflow tract Of the right ventricle. We obtained good longitudinal views of the aortic valve in all patients. Two of the 18 patients had poor image qua lity by TTE. The annular diameter by ICE correlated more closely with TEE t han with TTE. In conclusion, right-sided ICE. is a safe, simple, and useful procedure for observing the aortic valve during cardiac catheterization wi thout additional discomfort in the patients. Eight-sided ICE is superior to TTE in observing the aortic valve and measuring the annular diameter of th e valve. The annular diameter can be measured by ICE as precisely as by TEE . (J Am Soc Echocardiogr 1999;12:225-30.).