Use of contrast echocardiography for evaluation of right ventricular hemodynamics in the presence of ventricular septal defects.

Abstract

The use of a contrast agent is uniquely suited for describing intracardiac flow hemodynamics as it allows description of blood flow patterns within cardiac structures. While contrast echocardiography has been used to detect the presence of phenomena such as valvular insufficiency and right-to-left shunting across atrial or ventricular septal defects [1–3], it can further be used to evaluate abnormal pressure and flow states which may vary even in the presence of similar structural defects. As intracardiac pressure-flow relationships are altered by factors in addition to the size of the ventricular septal defect (VSD) itself, knowledge of the specific intracardiac flow pattern present can provide information permitting evaluation of the pulmonary vascular resistance and the presence or absence of pulmonic stenosis. In this chapter, contrast echocardiographic flow patterns present in varying hemodynamic states associated with a ventricular septal defect will be described to enable one to semiquantitatively assess right ventricular and pulmonary artery pressures. Such information coupled with estimation of total shunt size by techniques such as radionuclide angiography provides a very thorough evaluation of such a patient which in many instances would obviate the need for serial catheterizations.