Right Ventricular Morphology in PA/IVS: Integrating Developmental Pathology with Echocardiographic Prognostication

The management of pulmonary atresia with intact ventricular septum (PA/IVS) or critical pulmonary stenosis (CPS) in neonates continues to evolve, with a growing emphasis on individualized care based on right ventricular (RV) morphology. This commentary discusses and expands upon the recent study by Moras et al., which proposes echocardiographic classification of RV morphology—tripartite versus bipartite—as a predictive tool for post-intervention complications and a guide for intensive care management following transcatheter RV decompression. Integrating developmental cardiac anatomy, the commentary highlights how structural differences in RV segmentation influence physiological responses. Tripartite RVs are often susceptible to left ventricular (LV) dysfunction due to a sudden preload shift following decompression, requiring early inotropic support and delayed feeding strategies. In contrast, bipartite RVs are predisposed to dynamic outflow tract obstruction, often managed with beta-blockers and possible surgical shunting. The discussion also addresses the surgical versus catheter-based treatment decision in light of anatomical constraints such as RV-dependent coronary circulation and monopartite RVs. Additionally, the commentary reviews echocardiographic modalities used to assess RV function both prenatally and postnatally, including TAPSE, tissue Doppler imaging, myocardial performance index, and speckle-tracking echocardiography. It concludes by suggesting that early RV morphotype identification and function monitoring, even in fetal life, may enhance prognostication and therapeutic planning. This commentary advocates for a developmentally informed, phenotype-driven approach to neonatal cardiac care that bridges structural diagnosis with functional management.