Background: Pulmonary valve stenosis (PS) is a rare congenital heart disease in adults. Commissural fusion and narrowing of the central lumen are the basic pathology in valvular PS.Methods: This trial is a retrospective observational cohort study which is performed from 2011 to 2020 in 107 adult patients with congenital pulmonary valve stenosis, who were referred to Rajaie Cardiovascular Medical and Research Center, the largest referral center for congenital heart disease in adults in Iran. Procedural technique, immediate and up to one year follow-up of these patients, and the definition of successful intervention are described.Results: A total of 107 patients underwent percutaneous transcatheter pulmonary commissurotomy (PTPC). The mean age was 33.1 ± 12.8 years (18-79 years), of whom 46 (43%) were male. More than half of the patients (62.6%) had NYHA functional class ≥II before the intervention. The peak gradient of pulmonary valve (PVPG) decreased from 91 ± 34.7mmHg at baseline to 38.9 ± 16.1mmHg immediately post valvuloplasty (p = 0.032). The right ventricular systolic pressure (RVSP) decreased from 115.9 ± 34.1mmHg at baseline to 59.2 ± 20.1mmHg post procedure (p <0.001). Successful PTPC, based on transvalvular gradient (≤25 mmHg), was confirmed in 90 (85%) patients whereas when based on RVSP reduction>50%, the percentage of success rate was reduced to 42 (40%) of patients. The success rate after one year follow-up was 92.5%. After one year follow-up only 8 (7.5%) patients did not respond to PTPC (PVPG>25mmHg), of whom, about 4.5% had dysplastic valves and 3% had severe infundibular hypertrophy respectively. Also, in subgroup analysis we compared patients in two groups based on the RVSP reduction and transvalvular gradient.
Conclusion:The PTPC is a safe and efficient procedure in adult patients with severe pulmonary valve stenosis. Irrespective of sub-valvular gradient, in majority of cases, the gradient would be decreased significantly during one-year follow-up after PTPC (92.5% in this study). The use of beta blockers in patients with infundibular hypertrophy could reduce the gradient dramatically; in such a way that after 1 year the degree of residual gradient is minimal; so, we demonstrated that if the successful criteria in adult patients after PTPC being just only on the RVSP reduction>50%, it would lead to underestimation of effectiveness of PTPC; so, we suggest that the best criteria of successful PTPC in adult patients is post procedure peak systolic valvular gradient<25mmHg.