Structural heart disease

Abstract

A quality transthoracic echocardiographic study produces excellent and reproducible determination of the degree of aortic stenosis, and therefore, in most cases obviates the need for invasive hemodynamic study. However, in cases where transthoracic echo is not as reliable, such as morbid obesity with poor image quality, the catheterization laboratory may be important for determining the degree of stenosis. A simple pull-back across the aortic valve is often performed to yield a peak-to-peak gradient; however, this is just a crude estimate of the mean gradient. Preferentially, dual transducers should be employed to accurately determine the mean gradient.