Preditores de reestenose após valvoplastia mitral percutânea na estenose mitral reumática

Abstract

Introduction: Percutaneous mitral commissurotomy (PMC) is the primary choice of therapy for patients with rheumatic mitral stenosis (MS). However, restenosis can develop over time, becoming the main cause of functional deterioration after successful PMC. This study aims to assess the incidence of mitral restenosis and identify the primary factors associated with its occurrence after a successful PMC in patients with rheumatic MS. Methods: This is a cohort of patients with rheumatic MS who have undergone PMC between January 1997 and May 2023, followed at the Hospital das Clínicas of the Federal University of Minas Gerais (HC-UFMG). The primary outcome was the development of clinically significant mitral restenosis, defined as a reduction in mitral valve area (MVA) to less than 1.5 cm², resulting in cardiovascular death, the need for repeat PMC, or the indication for mitral valve replacement. Cox proportional hazards regression model was performed to identify pre and post procedural variables predictors of mitral restenosis. Spearman correlation test was used to evaluate the correlation of the levels of cytokines, chemokines, and growth factors with MVA at follow-up in a subgroup of patients. Results: A total of 380 patients were included in the study, with a mean age of 41.8 ± 12.1 years, and 322 patients were women (84.7%). The median follow-up time was 5.34 years (IQR 2.21-9.38). Restenosis occurred in 127 patients (33.4%) with an incidence of 5.1 events/100 patients/year (CI 95% 4.2-6.0%). The 5- and 10-years restenosis-free survival rates were 85.9 ± 2.1%, and 63.1 ± 3.5%, respectively. Variables independently associated with restenosis included age, Nunes score, post-PMC MVA, commissural opening, and brain natriuretic peptide (BNP) change. Additionally, post-PMC levels of TNF-α, IL-6, IL-15, IL-4, IL-5, IL-17, CXCL-10, FGF-basic, and VEGF were negatively correlated with MVA at follow-up. Conclusion: Restenosis remains prevalent despite a successful PMC and can be predicted by age, valve morphology, post-procedural valve area, commissural opening, and the degree of BNP reduction. In a subset of patients, the correlation between inflammatory markers and MVA suggests that persistent inflammation may be a critical driver of restenosis.