Transcatheter Harmony pulmonary valve placement in the right pulmonary artery followed by stenting of a hypoplastic left pulmonary artery.

We report the case of a 60-year-old man with repaired Tetralogy of Fallot and long-standing severe pulmonary insufficiency, complicated by asymmetric pulmonary blood flow and anatomy unsuitable for standard right ventricular outflow tract valve implantation. Cardiac imaging demonstrated a pyramidal right ventricular outflow tract that did not meet the oversizing criteria for a Harmony TPV 25, with the lack of interference with the inflow part of the device. In addition, the left pulmonary artery was severely hypoplastic with proximal stenosis. To avoid jailing the left pulmonary artery and high-risk unstable right ventricular outflow tract implant, a transcatheter Harmony valve was deployed in the right pulmonary artery while protecting the left pulmonary artery, followed by stenting of the left pulmonary artery. The goal was to ultimately eliminate the vast majority of pulmonary insufficiency and maintain antegrade flow across the left pulmonary artery. Hemodynamics demonstrated elevated right-sided pressures prior to intervention, which improved post-procedure. The patient tolerated the procedure well, with a transient postoperative diuretic requirement. At 10-month follow-up, he remained asymptomatic with improved left ventricular ejection fraction and a well-functioning Harmony valve on echocardiography. This case highlights the feasibility of branch pulmonary artery valve implantation using the Harmony valve in patients with unfavourable right ventricular outflow tract anatomy and demonstrates the value of simultaneous left pulmonary artery stenting to maintain relatively balanced pulmonary perfusion. Transcatheter branch pulmonary artery implantation may represent a viable option in carefully selected patients for whom conventional right ventricular outflow tract implantation is not possible.