Butcher, Steele C

BACKGROUND: Degenerative mitral regurgitation (DMR) due to valve prolapse predominates in men, but sex-specific differences are poorly understood due to a lack of quantitative and sex-stratified studies. METHODS: The international MIDA-Q (Mitral Regurgitation International Database-Quantitative) registry enrolled 3274 men and 2331 women with greater than or equal to mild DMR prospectively quantified, comprehensively characterized, and long-term follow-up. RESULTS: Women were more symptomatic despite lower effective regurgitant orifice (ERO, 27±18 versus 38±22 mm 2 , standardized mean difference 0.54; P <0.0001) and regurgitant volume (46±26 versus 61±31 mL/beat, standardized mean difference 0.52; P <0.0001), even for similar mitral lesions. With increasing ERO, women showed lower regurgitant volume, higher heart rate, lower blood pressure, but left ventricular size response in women was smaller in absolute measures while larger when body surface area normalized, with higher ejection fraction and cardiac index (all P <0.0001). Incidence of mitral valve surgery was similar in symptomatic women and men, but lower in asymptomatic women versus men (adjusted hazard ratio, 0.80 [0.69–0.94]; P =0.008) for similar ERO, linked to smaller left ventricular diastolic absolute diameter ( P <0.0001). Excess mortality under medical management (of severe versus mild ERO) was similar in women (adjusted hazard ratio, 1.67 [1.24–2.24]; P =0.0007) and men (adjusted hazard ratio, 1.63 [1.27–2.09]; P <0.0001) and versus expected survival (2.12 [1.51–2.98] in women and 2.27 [1.75–2.94] in men). However, moderate ERO (20–39 mm 2 ) was associated with significant excess mortality in women (1.47 [1.19–1.77] versus mild). In men, the corresponding hazard ratio did not reach statistical significance. Postoperative survival was similar in men and women. CONCLUSIONS: Women with DMR present with lower ERO and regurgitant volume than men and with considerable adaptive differences to increasing DMR severity versus men. Asymptomatic women are less referred to surgery than men of similar DMR severity, linked to smaller absolute left ventricular size. Severe DMR by similar quantitative thresholds causes similar excess mortality in men and women; moderate quantitative DMR shows a trend for higher excess mortality versus expected in women than men, requiring further confirmation. These data emphasize the importance of quantitative DMR and left ventricular remodeling assessment in men and women for appropriate clinical management.

Abstract Aims Indications for surgery in patients with degenerative mitral regurgitation (DMR) are increasingly liberal in all clinical guidelines but the role of secondary outcome determinants (left atrial volume index ≥60 mL/m2, atrial fibrillation, pulmonary artery systolic pressure ≥50 mmHg and moderate to severe tricuspid regurgitation) and their impact on post-operative outcome remain disputed. Whether these secondary outcome markers are just reflective of the DMR severity or intrinsically affect survival after DMR surgery is uncertain and may have critical importance in the management of patients with DMR. To address these gaps of knowledge the present study gathered a large cohort of patients with quantified DMR, accounted for the number of secondary outcome markers and examined their independent impact on survival after surgical correction of the DMR. Methods and results The Mitral Regurgitation International DAtabase-Quantitative registry includes patients with isolated DMR from centres across North America, Europe, and the Middle East. Patient enrolment extended from January 2003 to January 2020. All patients undergoing mitral valve surgery within 1 year of registry enrolment were selected. A total of 2276 patients [65 (55–73) years, 32% male] across five centres met study eligibility criteria. Over a median follow-up of 5.6 (3.6 to 8.7) years, 278 patients (12.2%) died. In a comprehensive multivariable Cox regression model adjusted for age, EuroSCORE II, symptoms, left ventricular ejection fraction (LVEF), left ventricular end-systolic diameter (LV ESD) and DMR severity, the number of secondary outcome determinants was independently associated with post-operative all-cause mortality, with adjusted hazard ratios of 1.56 [95% confidence interval (CI): 1.11–2.20, P = 0.011], 1.78 (95% CI: 1.23–2.58, P = 0.002) and 2.58 (95% CI: 1.73–3.83, P &lt; 0.0001) for patients with one, two, and three or four secondary outcome determinants, respectively. A model incorporating the number of secondary outcome determinants demonstrated a higher C-index and was significantly more concordant with post-operative mortality than models incorporating traditional Class I indications alone [the presence of symptoms (P = 0.0003), or LVEF ≤60% (P = 0.006), or LV ESD ≥40 mm (P = 0.014)], while there was no significant difference in concordance observed compared with a model that incorporated the number of Class I indications for surgery combined (P = 0.71). Conclusion In this large cohort of patients treated surgically for DMR, the presence and number of secondary outcome determinants was independently associated with post-surgical survival and demonstrated better outcome discrimination than traditional Class I indications for surgery. Randomised controlled trials are needed to determine if patients with severe DMR who demonstrate a cardiac phenotype with an increasing number of secondary outcome determinants would benefit from earlier surgery.