Association of Transforming Growth Factor-ß Superfamily Genes with Non-Regression of Pulmonary Artery Hypertension Following Balloon Mitral Valvotomy: A Pilot Study.

BACKGROUND AND AIM OF THE STUDY: Pulmonary arterial hypertension (PAH) is a common accompaniment of rheumatic mitral stenosis (MS), with 70% of patients showing evidence of different grades of PAH. The latter condition is found to be a prognostic factor influencing disease outcome even after interventional or surgical therapy. The cause of the non-regression of PAH following successful balloon mitral valvotomy (BMV) is not clear. Hence, the study aim was to determine if there is an association of mutations in the genes of the TGF-ß superfamily and non-regression of PAH in patients who undergo a successful BMV. METHODS: Forty-six patients who underwent BMV and fulfilled the recruitment criteria were enrolled prospectively in this case-control study. Among the patients, 27 had non-regression of PAH while 19 had regression of PAH and served as controls. The mean age of the population was 32.63 ± 10.65 years. RESULTS: No statistically significant differences were identified in any of the baseline parameters between the two groups. None of the samples had BMPR2 or ACVRL1 mutations. Ten of the patients and four of the controls were positive for Endoglin mutation, but the inter-group difference was not statistically significant (p = 0.25) CONCLUSIONS: The present study - the first of its kind - showed that deletion-duplication mutations in the BMPR2 or ACVRL1 genes may not be associated with non-regression of PAH, even after successful BMV, or in a wider sense serve as a contributor to PAH in rheumatic MS. The association of Endoglin mutation and non-regression of PAH warrants further investigation in a larger population.