Reflected ultrasound as a diagnostic instrument in study of mitral valve disease.

Abstract

Analysis of mitral valve motion in 200 patients revealed 75 normal, 44 with predominant mitral stenosis, and 81 with mixed mitral and aortic disease. Comparison with results from catheterization data, cine-angiography, surgery, apex cardiography, and phonocardiography was made. In patients with mitral stenosis, an ultrasound diastolic slope of less than 25 mm/sec. correlated well with a calculated mitral valve area of under 1 sq. cm, moderately severe stenosis on cineangiography, and a finger tip orifice at operation. Lesser degrees of stenosis were associated with slopes up to 45 mm/sec. No patient with the murmur of mitral stenosis with or without mitral insufficiency exhibited a slope of greater than 45 mm/sec. Normal mitral valve motion was accompanied by slopes in excess of 65 mm/sec. Amplitude of excursion generally diminished directly with the slope though with a wide scatter. A nearly normal amplitude was found in several patients with advanced mitral stenosis in whom the chordae apparatus was nearly intact. In mitral insufficiency, the diastolic slope varied from that seen with severe restriction (17 mm/sec.) to that seen with normal valves (over 65 mm/sec). The determining factor appeared to be degree of fibrosis, calcification, and chordae fusion present. Flail valves with high mobility were less likely to be the result of rheumatic involvement. In the presence of clinical signs of mitral insufficiency, a slope of less than 35 mm/sec, suggests severely damaged leaflets with fibrosis, with or without calcification, and some narrowing of the orifice with little of the normal ability to close. Slopes intermediate between 35 and 70 mm/sec, indicate lesser degrees of fixation.