Abstract 12207: Impact of Residual Pulmonary Stenosis on the Prognosis After Pulmonary Valve Replacement for Pulmonary Regurgitation

Abstract

Introduction: Pulmonary valve replacement (PVR) for pulmonary regurgitation (PR) was reported to provide beneficial effects on patients late after repair of tetralogy of Fallot (TOF). However, the impact of the degree of residual pulmonary stenosis (PS) in patients with severe PR remains unclear. Furthermore, the assessment of residual PS was difficult in patients with reduced RVEF. This study aimed to identify the impact of residual PS on the incidence of cardiovascular adverse events after PVR in preserved RVEF (pEF) or reduced RVEF (rEF) patients with PR late after repair of TOF. Methods: This was a single-center, retrospective review of 64 patients (56 repaired TOF-PS and 8 repaired TOF-pulmonary atresia) who underwent PVR for moderate to severe PR between 2003 and 2020. The threshold dividing pEF and rEF was 40%. Regarding residual PS, the definition the pressure gradient at the pulmonary valve in PSR group was 25 mmHg or more and less than 50mmHg. Patients were divided into 4 groups according to RVEF and the degree of residual PS (20 in PR-pEF, 12 in PSR-pEF, 25 in PR-rEF, 7 in PSR-rEF). Cardiovascular adverse events included cardiac death, prosthetic valve dysfunction, arrhythmia requiring treatment, and hospitalization for heart failure. Based on the above, the influence of hemodynamic parameters before PVR was analyzed. Results: The median follow-up period was 6.1 years [interquartile range 2.7-10]. There was no cardiac death and prosthetic valve dysfunction. Two patients died due to non-cardiac reason. Twenty-two (34%) patients showed cardiovascular adverse events. The cardiovascular adverse event-free rates were the highest in PSR-pEF group (100% at 5 years) and the lowest in PSR-rEF group (43% at 5 years) after PVR (log-rank p < 0.01), and 60% in PR-pEF and 70% in PR-rEF. In comparison between PSR groups, PSR-rEF had higher RVEDP (8±2 vs 13±2 mmHg, p < 0.01) and larger RAVI (71±25 vs 105±42 ml/m 2 , p=0.043). Conclusion: Patients with PSR-rEF had a high incidence of cardiovascular adverse events, high RVEDP, and large RAVI, suggesting RV adverse remodeling. The association between the degree of residual PS and RVEF should be taken into consideration on deciding the timing of PVR for PR.