Comparison of results of percutaneous mitral valvuloplasty in patients with large (>6 cm) versus those with smaller left atria

Abstract

To determine whether the presence of an aneurysmatic (severely enlarged) left atrium (>60 mm on echocardiography) influences results of percutaneous mitral valvuloplasty (PMV), the clinical, echocardiographic and hemodynamic characteristics and the results of this technique were compared in 46 consecutive patients with aneurysmatic left atrium (group I) and 125 consecutive patients without such echocardiographic finding (group II). Left atrial size was 70.5 ± 8 vs 50.1 ± 6 mm (p < 0.005) in groups I and II, respectively. Patients in group I were older (57 ± 12 vs 48 ± 12 years, p < 0.025), more symptomatic (New York Heart Association functional class ≥III or IV: 67 vs 42%, p < 0.05), and had atrial fibrillation more frequently (91 vs 44%, p < 0.001). The echocardiographic score (8.9 ± 1.9 vs 7.5 ± 2, p < 0.005) and the incidence of mild mitral regurgitation on angiography before PMV (54 vs 30%, p < 0.01) was also higher in group I patients. Hemodynamic parameters before PMV were similar in both groups, but after the procedure, final mitral valve area (1.61 ± 0.5 vs 1.95 ± 0.4 cm 2, p < 0.05) and the absolute increase in mitral area (0.81 ± 0.3 vs 1.02 ± 0.3 cm 2, p < 0.05) were lower and mean pulmonary artery pressure (35 ± 10 vs 28 ± 9 mm Hg, p < 0.025) was higher in group I. More difficulties in crossing the interatrial septum (9 vs 0%, p < 0.01) were also found in group I. PMV success (mitral valve area increase ≥50% without complications) tended to be lower (83 vs 94%, p < 0.1) and dilatation failure higher (11 vs 1%, p < 0.01) in group I, but the incidence of major complications was similar in both groups. An optimal result (final mitral valve area ≥1.5 cm 2) was found more frequently (88 vs 61%, p < 0.05) in group II patients. In addition, on multivariate analysis, an aneurysmatic left atrium was an independent predictor of PMV suboptimal results. In conclusion, patients with mitral stenosis and aneurysmatic left atrium may successfully undergo PMV, but they have more severe mitral valve disease and experience technically difficult procedures, dilatation failure and suboptimal results more often than patients with smaller left atria.