Non-rheumatic annular mitral stenosis: prevalence and characteristics.

Aims: To define the prevalence and characteristics of non-rheumatic annular mitral stenosis (AMS) in a general population as compared with rheumatic mitral stenosis (RMS).
Methods and Results: Clinical and echocardiographical variables were assessed in 70 patients with mitral stenosis. AMS and RMS patients were age- and gender-matched for the comparison of echocardiographic variables. Thirteen patients (18.5%) had AMS. Arterial hypertension and hypercholesterolemia were more prevalent in AMS (77 vs. 36% and 75 vs. 27%, respectively, P<0.05). Mitral annulus calcification severity score (2.2 vs. 1.3, P<0.05) and left ventricular mass (276+/-73 vs. 209+/-57 g, P<0.05) were significantly higher in AMS. Mitral valve area (MVA) was higher and mean gradient was lower (2.25+/-0.6 vs.1.9+/-0.6 cm2, 4+/-1.2 vs. 5.6+/-3.5 mmHg, P=ns) in AMS. Pressure half-time (PHT) MVA and planimetry MVA had a better correlation in RMS than in AMS patients (r=0.98 vs. 0.71, P<0.05).
Conclusion: AMS is more frequent than that is assumed and is associated with risk factors for coronary artery disease. AMS is generally mild and PHT may be less accurate for MVA calculation than in RMS.