Prognostic value of pre-operative atrial fibrillation in patients with heart failure and secondary mitral regurgitation undergoing percutaneous mitral valve repair with MitraClip

Background

Limited data are available regarding the independent prognostic role of atrial fibrillation (AF) after transcatheter mitral valve repair with MitraClip.

Aims

We sought to evaluate the real impact of pre-operative AF in a wide series of patients with heart failure (HF) and secondary mitral regurgitation (MR) after MitraClip treatment.

Methods

The study included 605 patients with severe secondary MR from a multicenter international registry. Patients were stratified into two groups according to the presence or absence of pre-operative AF. The overall prevalence of pre-operative AF was 44%. Primary endpoint was 5-year overall death, secondary endpoints were 5–year cardiac death and first re-hospitalization for acute HF.

Results

At 5-year Kaplan-Meier (KM) analysis conducted in the entire study cohort, compared to patients without AF those with AF had significantly more adverse events in term of overall death (67% vs. 43%; p<0.001) (KM curve A) and cardiac death (65% vs. 37%; p=0.001) (KM curve B) and, moderately more re-hospitalization for acute HF (64% vs. 50%; p=0.048) (KM curve C). To account for baseline differences, patients were propensity score matched 1:1. After matching, 342 adequately matched patients were identified: compared to patients without AF, those with AF had higher rates of death and cardiac mortality but similar rates of re-hospitalization for acute HF.

Conclusion

In this large 5-year analysis of patients with HF undergoing MitraClip treatment for severe secondary MR, AF is common and associated with higher rates of both overall- and cardiac-death. However, AF doesn't seem to affect the benefit of the procedure in term of re-hospitalization for HF.

Funding Acknowledgement

Type of funding source: None

428 Prognostic implications of the relationship between effective regurgitant orifice area and left ventricle end diastolic volume in patients with functional mitral regurgitation treated with MitraClip

Funding Acknowledgements

none

Background

The distinction between proportionate and disproportionate functional mitral regurgitation (FMR), based on the relationship between effective regurgitant orifice area (EROA) and left ventricle end diastolic volume (LVEDV), has recently been proposed as a possible new clinical and physiopathological framework to identify patients that could likely benefit from transcatheter mitral repair.

Purpose The aim of our study was to explore the possible prognostic implications of the EROA/LVEDV ratio in patients with FMR treated with MitraClip.

Methods – Baseline EROA/LVEDV was calculated in 137 patients with at least moderate-to-severe, symptomatic FMR treated with MitraClip. All patients underwent clinical, biochemichal and echocardiographic evaluation before MitraClip. EROA was calculated using PISA method. The primary outcome was a composite end-point of all-cause death or re-hospitalization for heart failure (HF).

Results – The median follow-up was 1.1 years. The primary outcome occurred in 59 patients (43 %). Population study showed a LVEDVi 113.52± 32.16 mL/m2, LVEF 29.75± 10.06% and EROA 39.45± 15.43 mm2.. The cut-off value of EROA/LVEDV ratio for primary outcome, identified by receiver operating characteristic curve, was 0.15 (AUC 0,65, p = 0.002) with a sensitivity and specificity of 78% and 52%, respectively. Patients were divided in two groups according to the identified cut-off. Patients with higher ratio (Group I, n = 88) presented a less dilated LV (LVEDVi: 105.1 ± 29.6 mL/m2 vs 128.2 ± 31.9 mL/m2, p < 0.001; LVESVi: 73.1 ± 27.7 mL/m2 vs 94.9 ± 29.05 mL/m2, p < 0.001), and a more severe MR (EROA: 47.9 ± 12.1 mm2 vs 25.1 ± 8.3 mm2, p < 0.001; vena contracta: 7.2 ± 1.3 mm vs 6.5 ± 1.3 mm, p = 0.008). There were no significant differences of left ventricle ejection fraction, right ventricle systolic function and systolic pulmonary pressure between the groups. At univariate analysis, EROA/LVEDV ratio >0.15 (HR = 2.223, 95% CI 1.121-4.411, p = 0.022), baseline evidence of atrial fibrillation (HR = 1.949, 95% CI 1.156-3.283, p = 0.012) and baseline pro-BNP (HR= 1.000, 95% CI 1.000-1.000, p = 0,001) were associated with a worse clinical outcome. At multivariate Cox-regression analysis, both EROA/LVEDV ratio >0.15 and baseline pro-BNP values were identified as independent predictors (HR 2.941, 95% CI 1.035-8.353, p = 0.043; HR = 1.000, 95% CI 1.000-1.000, p = 0.002, respectively). At Kaplan-Meier survival analysis, patients with EROA/LVEDV >0.15 had a significant lower freedom from composite endpoint (log-rank χ2 =5.517, p= 0.019; Fig. 1).

Conclusion

Our data show that EROA/LVEDV ratio was an independent predictor of adverse clinical outcome in FMR patients treated with MitraClip. This preliminary experience shows that this index could help to identify subgroups of patients with potential different clinical benefits from Mitraclip therapy. However, further and extended data are needed to provide more precise evidence.

Abstract 428 Figure. Fig. 1

P4728Prognostic implications of the relationship between effective regurgitant orifice area and left ventricle end diastolic volume in patients with functional mitral regurgitation treated with MitraClip

Background

The distinction between proportionate and disproportionate functional mitral regurgitation (FMR), based on the relationship between effective regurgitant orifice area (EROA) and left ventricle end diastolic volume (LVEDV), has recently been proposed as a possible new clinical and physiopathological concept to identify patients that could likely benefit from transcatheter mitral repair.

Purpose

The aim of our study was to explore the possible prognostic implications of the EROA/LVEDV ratio in patients with FMR treated with MitraClip.

Methods

Baseline EROA/LVEDV ratio was calculated in 72 patients with moderate-to-severe, symptomatic FMR treated with MitraClip. All patients underwent clinical, biochemichal and echocardiographic evaluation before MitraClip. EROA was calculated using PISA method. The primary outcome was a composite end-point of all-cause death or re-hospitalization for heart failure (HF).

Results

The median follow-up was 1 year. The primary outcome occurred in 25 patients (34.7%). The cut-off value of EROA/LVEDV ratio for primary outcome, identified by receiver operating characteristic curve, was 0.15 (p=0.007) with a sensitivity and specificity of 72 and 68%, respectively. Patients were divided in two groups according to the identified cut-off. Patients with higher ratio (Group I, n=35) presented a less dilated LV (LVEDVi: 113.2±33.4 mL vs 129.3±29.3 mL, p=0.033; LVESV: 140.7±49.0 mL vs 171.1±47.4 mL, p=0.010), a better LV systolic function (LVEF: 31.9±9.5% vs 27.8±5.8%, p=0.028) and a more severe MR (EROA: 44.5±12.9 mm2 vs 24.5±6.8 mm2, p<0.001; vena contracta: 7.4±1.5 mm vs 6.7±1.0 mm, p=0.045). Patients with lower ratio (Group II, n=37) showed a reduced prevalence of MV annular dilation (57.1% vs 91.7%, p=0.005) and a worse RV function (s'TDI: 9.2±2.2 cm/s vs 10.5±2.9 cm/s, p=0.039). At univariate analysis, EROA/LVEDV ratio >0.15 (HR = 2.467, 95% CI 1.017–5.982, p=0.046) and severe pulmonary hypertension (HR = 2.481, 95% CI 1.030–5.976, p=0.043) were associated with a worse clinical outcome. At multivariate Cox-regression analysis, both EROA/LVEDV ratio >0.15 and severe pulmonary hypertension were identified as independent predictors (HR 3.203, 95% CI 1–310–7.832, p=0.011; HR = 3.280, 95% CI 1.326–8.116, p=0.010, respectively).

Figure 1

Conclusion

Our data show that EROA/LVEDV ratio was an independent predictor of adverse clinical outcome in FMR patients treated with MitraClip. This preliminary experience shows that this index could help to identify subgroups of patients with potential different clinical benefits from MitraClip therapy. However, further and extended data are needed to provide more precise evidence.

Acknowledgement/Funding

None