732-4 Infundibular Diameter Predicts the Presence of Right Ventricular-Coronary Communications in Pulmonary Atresia with Intact Ventricular Septum

In patients with pulmonary atresia and intact ventricular septum (PA/IVS), the presence of right ventricular to coronary communications (RVCC) dictates surgical management (right ventricular (RV) decompression). Previously, tricuspid valve annulus size-Z score (TV-Z), and RV morphology have been used to predict the presence of RVCC. We hypothesize that pulmonary infundibular diameter better predicts the presence of RVCC than TV-Z score.MethodsFrom 2/91 to 7/94, 24 neonates with PA/IVS referred to our institution were studied (6 of which were prospectively evaluated). Four were excluded: 1 with associated Ebstein's anomaly and 3 with incomplete data. In the remaining 20 pts., echocardiographic measurements of the TV annulus and infundibular diameter were made, and angiograms were reviewed for the presence and extent of RVCC. Statistical analysis was performed using a two tailed student's t test.ResultsEleven pts with RVCC had significantly smaller infundibular diameter (2.3±07–mm)than nine pts without RVCC(6.5±1.6–mm), P<0.0001. All patient with RVCC had infundibular diameter < 3.4 mm. All patients without RVCC had infundibular diameter > 5.0–mm. While, the TV Z-score was also significantly smaller: –3.52±1.3 vs. –0.76±1.0, respectively, p<0.001, there was significant overlap between the groups. In all six cases studied prospectively, the presence of RVCC was predicted correctly, using the infundibular diameter.ConclusionThe infundibular diameter measured by Echo accurately predicts the presence of RV-coronary communications in neonates with PA/IVS. This method better distinguishes the presence or absence of RVCC than TV-Z score