Bronchial hyperreactivity in patients with mitral stenosis before and after successful percutaneous mitral balloon valvulotomy

Objectives: We aimed to identify the bronchial response to inhaled methacho line in patients with mitral stenosis (MS) and to clarify whether or not th e bronchial hyperreactivity (BHR) is reversible after percutaneous mitral b alloon valvulotomy (PBMV). Patients and setting: Thirty patients with MS and 28 age-matched healthy! c ontrol subjects were prospectively evaluated with pulmonary function tests and methacholine challenge. The productive concentration of methacholine ca using 20% decrease in FEV1 (PC20) was calculated and used as a parameter of bronchial responsiveness, BHR was defined as a PC20 < 8 mg/mL, Mean pulmon ary artery pressure (PAP) and mean pulmonary capillary wedge pressure (PCWP ) were recorded in all patients through a Swan-Ganz balloon-tipped catheter . Sixteen patients underwent PMBV, and a methacholine test was repeated aft er each procedure. Results: Bronchial response to methacholine was significantly increased in patients with MS, so that 53% of them had BHR, whereas all control subjects were nonresponders. The PC,, was closely correlated with the PAP (r = -0.7 77; p < 0.001), PCWP (r = - 0.723; p < 0.001), and I mitral valve area (MVA ; r = 0.676; p < 0.001). Balloon valvulotomy was successfully performed in i all of the 16 patients, and the cardiac parameters (MVA, PAP, and PCWP) s ignificantly improved after the procedure, In contrast, no significant chan ges were shown in pulmonary function test variables (total lung capacity, v ital capacity [VC], FEVI, and FEVI/VC). Although significant improvement wa s observed in the mean PC20 values (from 4.97 +/- 5.24 to 7.47 +/- 6.96 mg/ mL; p 0.0006), BHR was completely eliminated in only one patient, Conclusions: Our data shows that BHR is fairly common among patients with M S, and severity of bronchial responsiveness is significantly correlated nit h the severity of MS, Moreover, PMBV leads to significant I eduction in pul monary congestion and a consequent improvement in BHR.