Incidence of Underreferral to Multidisciplinary Evaluation in Severe Primary Mitral Regurgitation.

Background: Severe primary mitral regurgitation (MR) warrants multidisciplinary evaluation involving cardiac surgeons and structural interventional cardiologists. The incidence and potential impact on outcomes of missed evaluation remain unknown. Methods: We conducted a retrospective cohort study of patients with new diagnoses of severe primary MR from an echocardiography database within a large health care network. Of 37,749 unique patients with echocardiograms, 126 had severe primary MR. We compared the 2-year survival of patients who did and did not undergo multidisciplinary evaluation. Propensity score matching was performed on the basis of The Society of Thoracic Surgeons Predicted Risk of Mortality for mitral repair. Results: Of 126 patients with severe primary MR (median age, 79 years [interquartile range, 68-89 years]; 60% women), 37 (29%) underwent multidisciplinary evaluation. Evaluated patients were younger (71 [58-79] years vs 84 [73-90] years), and of those, 26 (70%) underwent operations within 37 days of evaluation. The Society of Thoracic Surgeons Predicted Risk of Mortality median was 1% (1%-5%) and 4% (1%-10%) for evaluated and unevaluated patients, respectively. Of the 74 patients matched, the mortality rate was lower in evaluated patients at 90 days (11% [n = 4] vs 27% [n = 10]; Conclusions: The multidisciplinary referral rate for newly identified severe primary MR was low at 29%, with underreferral of low-risk, potentially operative candidates. The observed improved survival with multidisciplinary evaluation calls for efforts to maximize referral of this group of patients.