Effect of Inoue balloon mitral valvotomy on severe pulmonary arterial hypertension in 315 patients with rheumatic mitral stenosis: Immediate and long-term results

Background and aims of the study: Despite advances in surgical techniques, mitral valve surgery in patients with severe pulmonary arterial hypertensio n (FAH) causes considerable mortality and morbidity. Balloon mitral valvoto my (BMV) is an established alternative to treat high-risk surgical patients with mitral stenosis (MS). The study aims were to evaluate immediate and l ong-term efficacy of BMV in patients with MS and severe PAH, compared to th ose with mild/moderate FAH. Methods: Among 1,125 patients who underwent Inoue BMV, 315 had severe PAH ( mean pulmonary artery (PA) pressure greater than or equal to 50 mmHg (group I; 79 of these patients had suprasystemic PAH). Results from this group we re compared with those of patients with mild/moderate PAH (group II). Results: Group I patients were younger and more symptomatic (mean PA pressu re 62 +/- 10.6 mmHg versus 32.6 +/- 8.2 mmHg in group II). Before BMV, mean transmitral gradient (17.8 +/- 6.5 versus 14.4 +/- 5.4 mmHg) and pulmonary capillary wedge pressure (PCWP) (31.6 +/- 6.1 versus 22.8 +/- 6.2 mmHg) we re significantly higher, while mitral valve area (MVA) (0.66 +/- 0.2 versus 0.85 +/- 0.2 cm(2)) was significantly lower in group I. After BMV, PA mean pressure was significantly reduced (34.8 +/- 11.2 and 21.1 +/- 8.4 mmHg), transmitral gradient (8.0 +/- 3.9 and 6.9 +/- 3.2 mmHg) and mean PCWP (12.8 +/- 5.8 and 11.0 +/- 5.1 mmHg) in groups I and II, respectively, with a co mparable increase in MVA (1.77 +/- 0.4 and 1.84 +/- 0.5 cm(2)). Group I pat ients had worse baseline hemodynamic parameters than group II, but the form er had a higher absolute gain in hemodynamic parameters. Residual severe PA H after BMV was seen in 9.8% of patients, with PA pressures normalized in 9 .5%. Among 79 patients with suprasystemic PA pressure (mean PA systolic pre ssure 116.6 +/- 28.2 mmHg), 16.5% normalized their PA pressures and 25.3% h ad residual severe PAH. At mean follow up of 33 months, 80.4% were in NYHA class I. Mean PA systolic pressure in 161 patients was 39.0 +/- 14.2 mmHg c ompared with a post-BMV value of 55.0 +/- 16.9 mmHg; thus, a sustained fall in pressure was demonstrated at follow up. Conclusion: Inoue BMV is safe and effective in patients with MS and severe PAH. Although these patients have worse clinical and hemodynamic parameters before BMV, they achieve a greater absolute gain in terms of improvement i n all hemodynamic parameters.