Mitral regurgitation: relationship of noninvasive descriptors of right and left ventricular performance to clinical and hemodynamic findings and to prognosis in medically and surgically treated patients.

Abstract

To determine objective predictors of survival, 53 patients with chronic, hemodynamically severe mitral regurgitation underwent rest and exercise radionuclide cineangiography, echocardiography, treadmill exercise testing, and ambulatory electrocardiographic monitoring before prospective (average 30 month) follow-up. At entry, symptom status correlated best with radionuclide-based right ventricular ejection fraction (RVEF) and left atrial size, while treadmill exercise tolerance correlated best with RVEF during exercise (r = .48, p less than .005). Correspondingly, in 23 patients who underwent cardiac catheterization, pulmonary arterial systolic and wedge pressures were significantly inversely related to RVEF. On the 24 hr ambulatory electrocardiogram, nonsustained ventricular tachycardia was present in 29% of patients, most frequently when both RVEF and left ventricular ejection fraction (LVEF) were subnormal (p = .03 vs other patients). Since entry, 35 patients have been managed without surgery for 9 to 57 months (average 28); three of these who subsequently underwent operation also are among the 21 patients who have undergone mitral valve replacement (MVR). During the average 28 months of observation under medical treatment five of 35 nonoperated patients have died; all five were among the six nonoperated patients with RVEFs of 30% or less at entry, a descriptor that significantly identified those at high mortality risk (p less than .0001 vs patients with RVEFs greater than 30%). All five also were among the eight nonoperated patients with LVEFs of 45% or less (lower limit of normal), a descriptor that also significantly predicted mortality. Three of the 21 patients who underwent surgery have died, all late after MVR. Among operated patients, only age was a predictor of postoperative survival. A trend toward improved survival was found in the patients with depressed right or left ventricular ejection fraction who underwent surgery compared with those who did not.