Long-term hemodynamic benefits after ‘treat-to-close’ for intracardiac shunts and pulmonary hypertension

Background: Patients with congenital heart defects and systemic-to-pulmonary pre-tricuspid shunts (PTS) may develop pulmonary arterial hypertension (PAH) from chronic volume overload. PTS patients with PAH can undergo medical therapy followed by closure (treat-to-close) with safe short-term outcomes. This may result in improved pulmonary resistance, compliance and RV function, but severe distal vascular disease may persist. Aims and Objectives: To examine longitudinal hemodynamic changes in pulmonary vascular load and RV function from diagnosis, post-shunt closure and long-term follow up in patients with PTS with PAH. Methods: PTS subjects with PAH who underwent treat-to-close and had at least one early post-closure and late resting and exercise cath were identified. RV afterload (Ea, Ca, resting PVR, exercise α and linear PQ), RV contractility (Ees) and RV-PA coupling (Ees/Ea) were analyzed. Results: 3 subjects (2 ASDs, 1 PAPVR) were included. Closure resulted in short- and long-term reduction in mean PA pressure, PVR (Fig A and B) and global afterload with improved RV-PA coupling (Fig C). Exercise PQ and α remained abnormal (Fig C). Conclusions: Treat-to-close for PTS with PAH provides short- and long-term improvements suggesting benefit of this aggressive approach. However, distal vascular disease remains despite near normalization of global afterload and chronic medical therapy may still be needed.