Should an Inoue balloon larger than suggested by guidelines be used for percutaneous balloon mitral valvuloplasty?

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the immediate and long-term results of single inflation using a larger balloon size in patients with symptomatic rheumatic mitral stenosis (MS) METHODS: Among a study population of 231 patients with MS, percutaneous balloon mitral valvuloplasty (PBMV) was performed using the Inoue balloon technique. The ideal balloon size was measured according to the patients' height. Patients were allocated at random to two groups: a stepwise method was used in 115 patients (group 1), and a single-inflation method (with +2 mm larger balloon size) in 116 patients (group 2). Follow up was scheduled at six-month intervals for the first year, and annually thereafter. Patients were followed up until 2009.

RESULTS: The mitral valve area (MVA) was increased from pre-PBMV values of 1.2 +/- 0.3 cm2 and 1.1 +/- 0.21 cm2 in groups 1 and 2, respectively, to post-PBMV values of 1.9 +/- 0.34 cm2 and 2.0 +/- 0.28 cm2 in groups 1 and 2, respectively; the increase in MVA for each group was statistically significant (p < 0.01) The mean transmitral pressure gradient (MMG) was decreased from pre-PBMV values of 14.1 +/- 5.5 mmHg and 13.2 +/- 5.9 mmHg in groups 1 and 2, respectively, to post-PBMV values of 5.9 +/- 2.3 mmHg and 5 +/- 2.5 mmHg in groups 1 and 2, respectively. One patient in group 2 underwent surgery due to severe mitral regurgitation. The procedure time was significantly shorter in group 2 (32 +/- 11.5 min versus 25 +/- 11 min; p < 0.001). The mean follow up duration was 49.5 +/- 19.2 months (range: 24-84 months). At the last follow up examination, the MVA was shown to be significantly larger in group 2 than in group 1 (1.65 +/- 0.3 versus 1.42 +/- 0.34 cm2; p = 0.02), while the MMG was lower (9 +/- 3.6 versus 6.7 +/- 3 mmHg; p = 0.017).

CONCLUSION: The study results suggested that using a +2 mm larger balloon size with single overinflation may represent an alternative and effective therapy, with a shorter procedure time.