[2-dimensional echocardiographic measurement of the valvular area in mitral stenosis. Surgical correlations]

The calculation of mitral valve orifice area in patients with mitral stenosis is important because it establish the surgical indication and the type of surgical procedure to be done (commisurotomy, valvuloplasty or valve replacement). Moreover, the postoperative measurement of the mitral orifice area may be useful to evaluate the surgical results and to differentiate between inadequate commisurotomy and restenosis. We studied 12 patients with measurement of mitral orifice area by two-dimensional echocardiography imaging and digital microproccesing. The measurements were compared with the surgeon's estimate. The correlation obtained was of r = 0.86 (p less than or equal to 0.05). The description of the surgeon corroborated the echocardiographic findings respecting mitral subvalvular apparatus in all except one patient. Concerning the thickening of the values, echocardiographic and surgical findings were concordant in 10 patients. The mitral orifice area showed inverse relationship with pulmonary artery wedge pressure measured by catheterization in 5 patients (r = -0.844). After commisurotomy, the mitral orifice area was analyzed in 9 patients, since one patient requerired valve replacement and in two we did not obtain echocardiographic studies. The postoperative increase of the mitral orifice area was significant; (before surgery X 0.6 cm2 +/- 0.16) and after surgery (X 2.7 cm2 +/- 0.22) p less than or equal to 0.001).