Transthoracic Echocardiographic Assessment of Coronary Flow in the Diagnosis of Right Ventricular-Dependent Coronary Circulation in Pulmonary Atresia with Intact Ventricular Septum

Abstract

Right ventricular-dependent coronary circulation (RVDCC) is associated with pulmonary atresia with intact ventricular septum and is defined by two or more epicardial coronary arteries with atresia or severe stenosis resulting in the dependency of coronary supply by retrograde flow. The hypothesis of this study is that coronary Doppler flow patterns on echocardiography can be used to distinguish patients with RVDCC. Between 2007 and 2016, we reviewed 16 patients with pulmonary atresia or critical pulmonary stenosis. Patients were divided into two groups, those with RVDCC (determined by angiography or pathology evaluation) and those without. Echocardiographic evaluation of the coronary arteries included 2-dimensional measurements and pulse wave Doppler flow pattern in 3 epicardial coronary arteries. Velocity-time integral (VTI) and maximal velocity (V) were measured and compared between the two groups. Three coronary flow patterns were demonstrated: (1) all antegrade flow, (2) antegrade to retrograde VTI flow ratio > 1, and (3) antegrade to retrograde VTI flow ratio ≤ 1. Of the 7 patients with RVDCC, 6 (86%) had evidence of flow pattern 3 in ≥ 2 of the 3 coronary arteries in contrast to 0 (0%) of the non-RVDCC patients (p = 0.001). Higher retrograde V was associated with RVDCC (p < 0.001) and coronary artery dilatation with Z-score ≥ + 3 was also associated with RVDCC (p = 0.02). Echocardiographic evaluation of the coronaries can be useful in identifying RVDCC. More retrograde flow in at least two coronary arteries is strongly suggestive of RVDCC. Dilatation of the coronary arteries is also supportive evidence.

A retrograde approach for transcatheter valvotomy procedure in infants with pulmonary atresia intact ventricular septum (PA-IVS): retrograde versus antegrade approach

“…RVDCC, which is the primary concern that can be missed during echocardiography, may be ruled out by aortogram. 16 Two accesses (vein and arterial access) may take time and may cause haematoma due to multiple puncture attempts; 2) Retrograde approach use may hinder unnecessary bending of the catheter, which might affect its steerability for valvotomy purpose compared to the usual (antegrade) approach (Fig 2). These facts were proven by shorter PA-RV crossing time in the retrograde approach, and one patient was switched from antegrade to retrograde approach due to being unable to position the tip catheter in front of the pulmonary valve from the antegrade approach.…”

Procedural Sedation in Congenital Heart Disease

“…In this rare CHD, coronary circulation is a balance between forward flow to the coronary artery and retrograde flow from the right ventricle. 18,19 This typically occurs with one or several coronary arteries with varying degrees of stenosis or mid-distance occlusion. 18,19 Thus, a portion of the coronary flow is supplied via the aorta and the other from the hypertensive right ventricle via sinusoids.…”

“…18,19 This typically occurs with one or several coronary arteries with varying degrees of stenosis or mid-distance occlusion. 18,19 Thus, a portion of the coronary flow is supplied via the aorta and the other from the hypertensive right ventricle via sinusoids. It is well known that decreasing right ventricular pressure is fatal in this situation, but equally as dangerous is decreasing systemic vascular resistance.…”