Percutaneous Balloon Mitral Valvuloplasty Using the Inoue Balloon in Children and Adolescents: A Prospective Interventional Before–After Study from a Low-Resource Setting

Abstract

Objectives: This study aimed to evaluate the procedural success, safety profile, and immediate hemodynamic outcomes of percutaneous balloon mitral valvuloplasty (PBMV) using the Inoue balloon in children and adolescents with severe rheumatic mitral stenosis (RMS). Methodology: A prospective interventional before–after design was conducted at the pediatric cardiology department of a major tertiary cardiac center in Pakistan from March 2024 to September 2025. Forty-eight patients under 18 years with severe RMS (mitral valve area ≤1.0 cm²) were enrolled through consecutive sampling. All underwent PBMV using the Inoue balloon technique. Echocardiographic parameters—including mitral valve area (MVA), transmitral gradient, pulmonary artery pressure (PAP), and mitral regurgitation (MR)—were assessed before and immediately after the procedure. Statistical analysis was performed using paired tests, with p<0.05 considered significant. Results: The median age was 15 years (IQR 14–16), and 56.3% were male. PBMV resulted in a significant increase in MVA from 0.7 cm² to 1.6 cm² (p<0.001) and a substantial reduction in transmitral gradient (23 to 7.5 mmHg, p<0.001) and PAP (52 to 35 mmHg, p<0.001). Mild MR developed in 35.4% and moderate MR in 8.3% of patients, with no cases of severe MR. Procedural success was achieved in 83.3% of the cohort. No mortality, cardiac tamponade, or major complications occurred. Mean hospital stay was 2.2±0.5 days. Conclusion: PBMV using the Inoue balloon is a safe, effective, and practical therapeutic option for relieving severe RMS in children and adolescents. The technique provides rapid hemodynamic improvement, low complication rates, and short hospitalization, making it particularly valuable in low-resource regions where rheumatic heart disease remains highly prevalent.