Prognostic Value of Right Ventricular Afterload in Patients Undergoing Mitral Transcatheter Edge-to-Edge Repair

Abstract

Background: Pulmonary hypertension (PH) and secondary mitral regurgitation (MR) are associated with adverse outcomes after mitral transcatheter edge-to-edge repair. We aim to study the prognostic value of invasively measured right ventricular afterload in patients undergoing mitral transcatheter edge-to-edge repair.

Methods and results: We identified patients who underwent right heart catheterization ≤1 month before transcatheter edge-to-edge repair. The end points were all-cause mortality and a composite of mortality and heart failure hospitalization at 2 years. Using the receiver operating characteristic curve-derived threshold of 0.6 for pulmonary effective arterial elastance ([Ea], pulmonary artery systolic pressure/stroke volume), patients were stratified into 3 profiles based on PH severity (low elastance [HE]: Ea <0.6/mean pulmonary artery pressure (mPAP)) <35; High Elastance with No/Mild PH (HE-): Ea ≥0.6/mPAP <35; and HE with Moderate/Severe PH (HE+): Ea ≥0.6/mPAP ≥35) and MR pathogenesis (Primary MR [PMR])/low elastance, PMR/HE, and secondary MR). The association between this classification and clinical outcomes was examined using Cox regression. Among 114 patients included, 50.9% had PMR. Mean±SD age was 74.7±10.6 years. Patients with Ea ≥0.6 were more likely to have diabetes, atrial fibrillation, New York Heart Association III/IV status, and secondary MR (all P<0.05). Overall, 2-year cumulative survival was 71.1% and was lower in patients with secondary MR and mPAP ≥35. Compared with patients with low elastance, cumulative 2-year event-free survival was significantly lower in HE- and HE+ patients (85.5% versus 50.4% versus 41.0%, respectively, P=0.001). Also, cumulative 2-year event-free survival was significantly higher in patients with PMR/low elastance when compared with PMR/HE and patients with secondary mitral regurgitation (85.5% versus 55.5% versus 46.1%, respectively, P=0.005).

Conclusions: Assessment of the preprocedural cardiopulmonary profile based on mPAP, MR pathogenesis, and Ea guides patient selection by identifying hemodynamic features that indicate likely benefit from mitral-transcatheter edge-to-edge repair in PH or lack thereof.

Keywords: mitral regurgitation; mitral transcatheter edge‐to‐edge repair; pulmonary effective arterial elastance; pulmonary hypertension; right ventricular afterload.

Figure 1. Survival analysis according to elastance.

Kaplan–Meier analysis showing lower event‐free survival in patients with high Ea for all‐cause mortality (A) and the composite end point (B). Ea indicates elastance; and HR, hazard ratio.

Figure 2. Forest plot of invasive hemodynamic univariate predictors associated with 2‐year outcomes after M‐TEER.

mPAP indicates mean pulmonary artery pressure; M‐TEER, mitral transcatheter edge‐to‐edge repair; PA, pulmonary artery; PADP, pulmonary artery diastolic pressure; PASP, pulmonary artery systolic pressure; PCWP, pulmonary capillary wedge pressure; PVR, pulmonary vascular resistance; RV, right ventricle; and TPG, transpulmonary pressure gradient.

Figure 3. Stratification of the study population into 3 cardiopulmonary hemodynamic profiles.

Scatter plot showing patient distribution based on the cutoffs set for mPAP (35 mm Hg) and Ea (0.6 mm Hg/mL). Ea indicates elastance; HE−, high elastance (>0.6) and low mPAP (<35 mm Hg); HE+, high elastance (>0.6) and high mPAP (>35 mm Hg); LE, low elastance (<0.6); mPAP, mean pulmonary artery pressure; and PA, pulmonary artery.

Figure 4. Survival analysis according to the 3 cardiopulmonary hemodynamic profiles by PH severity.

Kaplan–Meier analysis showed lower event‐free survival in patients with the HE−/HE+ profiles for all‐cause mortality (A) and the composite end point (B). HR, hazard ratio; HE−, high elastance (>0.6) and low mPAP (<35 mm Hg); HE+, high elastance (>0.6) and high mPAP (>35 mm Hg); LE, low elastance (<0.6); mPAP, mean pulmonary artery pressure; and PH, pulmonary hypertension.

Figure 5. Predictors of the composite outcome after mitral TEER.

Forest plot showing multivariable predictors associated with the 2‐year composite end point of mortality and heart failure hospitalization after mitral TEER. LVEF indicates left ventricular ejection fraction; MR, mitral regurgitation; and TEER, transcatheter edge‐to‐edge repair.

Figure 6. Three hemodynamic profiles were created based on Ea=0.6 and mPAP=35.

Patients with LE (mPAP <35, Ea <0.6) were compared with patients with HE− (mPAP <35, Ea ≥0.6) and HE+ (mPAP ≥35, Ea≥0.6). No patients had Ea <0.6 and mPAP ≥35 mm Hg. Compared with patients with the LE hemodynamic profile, event‐free survival for the composite end point was lower in those with the HE− (mPAP <35, Ea ≥0.6) and HE+ (mPAP ≥35, Ea ≥0.6) hemodynamic profiles at 1 and 2 years of follow‐up. Ea indicates elastance; HR, hazard ratio; HE−, high elastance (>0.6) and low mPAP (<35 mm Hg); HE+, high elastance (>0.6) and high mPAP (>35 mm Hg); LE, low elastance (<0.6); mPAP, mean pulmonary artery pressure; and PA, pulmonary artery.