Impact of Mitral Regurgitation on Clinical Outcomes After Transcatheter Aortic Valve Implantation

Mechanisms and implications of mitral regurgitation in patients with severe aortic stenosis who received transcatheter aortic valve replacement

INTRODUCTION

This study aimed to investigate the mechanisms and clinical implications of mitral regurgitation (MR) in patients with severe aortic stenosis (AS) who received transcatheter aortic valve replacement (TAVR).

METHODS

We conducted retrospective echocardiographic analyses at baseline and 6 months after TAVR in 140 patients with symptomatic AS (85 ± 5 years) who underwent TAVR. We defined significant MR as ≥ moderate based on evaluation of transthoracic echocardiography (TTE).

RESULTS

There were 48 patients (34%) with preexisting MR at the baseline. Among measured TTE parameters, end-systolic wall stress (ESWS), mitral annulus area, and mitral valve thickening index were independent factors associated with preexisting MR (odds ratio [OR]: 1.013, 95% confidence interval [CI]: 1.005-1.021; OR: 1.740, 95% CI: 1.314-2.376; OR: 2.306, 95% CI: 1.426-3.848; respectively). Six months after TAVR, there were 34 patients with post-existing MR, A history of atrial fibrillation and ESWS after TAVR were independent factors (OR: 3.013, 95% CI: 1.208-7.556; OR: 1.013, 95% CI: 1.000-1.023; respectively). The Kaplan-Meier plot indicated that preexisting MR was a risk factor for heart failure-related events within 1 year of discharge after TAVR (p = .012).

CONCLUSIONS

In patients who underwent TAVR for severe AS, preexisting MR was associated with having a thickened mitral valve and large mitral annulus size induced by high ESWS. These patients may have worse prognosis after TAVR and should be closely monitored in the long term.

Clinical impact and evolution of mitral regurgitation after TAVI using the new generation self-expandable valves

BACKGROUND

Concomitant mitral regurgitation (MR) impaired prognosis in patients undergoing transcatheter aortic valve implantation (TAVI). It has been suggested that the use of first generation self-expandable valve in patients with significant MR is associated with worse outcome as compared with balloon expandable valve. However, the impact of newer generation transcatheter devices on MR has not been investigated so far. We aim to assess the prognostic impact of MR in patients undergoing TAVI with the first-generation vs. the latest generation of self-expandable valves.

METHODS

We analyzed 2964 consecutive patients who underwent TAVI. Patients were classified into 4 groups according to the degree of baseline MR and the generation of self expandable valve implanted.

RESULTS

Of 1234 patients with moderate or severe MR, 817 were treated with first generation and 417 patients with second generation valves. Whereas, of 1730 patients with no or mild MR, 1130 were treated with first generation and 600 patients with second generation valves. Although, concomitant moderate-severe MR was found to be an independent predictor of mortality after TAVI, the use of newer generation self expandable valves was associated with higher survival rate at 1 year irrespective of the degree of preprocedural MR. At multivariable analysis the use of newer generation valve was associated with MR improvement throughout 1 year follow-up.

CONCLUSION

Baseline moderate-severe MR is associated with an increase in mortality after TAVI. However, the degree of preprocedural MR doesn't impact survival when a second generation self expandable valve is used.

Adaptive development of concomitant secondary mitral and tricuspid regurgitation after transcatheter aortic valve replacement

AIMS

Concomitant secondary atrioventricular regurgitation is frequent in patients with severe aortic stenosis scheduled for transcatheter aortic valve replacement (TAVR). The future implications of leaving associated valve lesions untreated after TAVR remain unknown. Aim of the present study was to characterize the evolution of concomitant secondary atrioventricular regurgitations and to evaluate their impact on long-term prognosis.

METHODS AND RESULTS

We prospectively enrolled 429 consecutive TAVR patients. All patients underwent comprehensive clinical, laboratory, and echocardiographic assessments prior to TAVR, at discharge, and yearly thereafter. All-cause mortality was chosen as primary study endpoint. At baseline, severe concomitant secondary mitral regurgitation (sMR) was present in 54 (13%) and severe concomitant secondary tricuspid regurgitation (sTR) in 75 patients (17%). After TAVR 59% of patients with severe sMR at baseline experienced sMR regression, whereas analogously sTR regressed in 43% of patients with severe sTR. Persistence of sTR and sMR were associated with excess mortality after adjustment for our bootstrap-selected confounder model with an adjusted HR of 2.44 (95% CI 1.15-5.20, P = 0.021) for sMR and of 2.09 (95% CI 1.20-3.66, P = 0.01) for sTR. Patients showing regression of atrioventricular regurgitation exhibited survival rates indistinguishable to those seen in patients without concomitant atrioventricular regurgitation (sMR: P = 0.83; sTR: P = 0.74).

CONCLUSION

Concomitant secondary atrioventricular regurgitation in patients with severe AS is a highly dynamic process with up to half of all patients showing regression of associated valvular regurgitation after TAVR and subsequent favourable post-interventional outcome. Persistent atrioventricular regurgitation is a major determinant of unfavourable outcome after TAVR and proposes a window of early sequel intervention.

Mitral regurgitation after transcatheter aortic valve replacement

Patients undergoing transcatheter aortic valve replacement (TAVR) might have an associated significant MR that can potentially lead to left ventricular (LV) failure after procedure. Considering the specific alterations in the mitral valve in TAVR scenario and the widespread use of TAVR in recent years, it appears important to know and understand the anatomical, functional and clinical implications to develop adequate strategies for the future. Patients with severe mitral regurgitation (MR) have been generally excluded from randomized clinical trials, making poor the impact that associated MR can have on clinical outcomes after TAVR. Several factors must be considered whose presence influences the severity of MR. For example, the elevated prevalence of coronary disease with consequent ischemic MR may account for LV dilation observed at the end stage of aortic stenosis. Evidence randomized studies and registries suggests that the rate of concomitant moderate-to-severe MR in patients undergoing TAVR oscillates between 2% and 33%, and patients with moderate to severe MR may have hemodynamic frailty with clinical deterioration during mechanical intervention. Short- and long-term outcomes, including cardiac mortality, appear to be influenced by the existence of preoperative moderate-to-severe MR or by the postprocedural worsening of mild MR, generally due to adverse LV remodeling. The incidence and the prognostic effect of concomitant MR in patients undergoing TAVR requires specific attention as might trigger adjunctive strategy treatment which should be carefully evaluated in clinical trials.

Higher preoperative left atrial volume index predicts lack of mitral regurgitation improvement after transcatheter aortic valve replacement

BACKGROUND

Moderate-to-severe mitral regurgitation is present in 20-35% of patients undergoing transcatheter aortic valve replacement (TAVR) and the current literature lacks simple echocardiographic parameters, which can predict post-TAVR changes in mitral regurgitation. The aim of this study is to investigate the echocardiographic predictors of improvement or worsening of mitral regurgitation in patients undergoing TAVR with moderate-to-severe mitral regurgitation.

METHODS

This retrospective study included 113 patients who underwent TAVR with preoperative mitral regurgitation grade at least 2. Patients with concomitant coronary artery disease requiring treatment were excluded. Mitral regurgitation was related to the annular dilatation or tethering mechanism in all patients. Preoperative and postoperative echocardiographies were compared in terms of mitral regurgitation and other commonly measured parameters.

RESULTS

After TAVR, a reduction in mitral regurgitation was observed in 62.8% of cases. On the basis of the difference between postoperative and preoperative echocardiograms, 71 patients had improved mitral regurgitation, whereas 42 patients had stable or worsened mitral regurgitation. After analyzing preoperative echocardiographic parameters with regard to this group difference, left atrial volume index (LAVI) was the only variable that was different between groups (33.4 ± 4.8 ml/m in improved mitral regurgitation vs. 39.8 ± 3.0 ml/m in not improved mitral regurgitation, P < 0.001). In a multivariable logistic regression model, a LAVI increase was associated with lack of an acute reduction in mitral regurgitation (odds ratio = 1.41, P < 0.001) after adjustment for age and preoperative serum creatinine.

CONCLUSION

Higher preoperative LAVI is a determinant predictor of lack of an acute reduction in mitral regurgitation after TAVR, and LAVI could be used as a stratifying tool to tailor the treatment strategy and the timing of the procedures. However, validation of these results and long-term outcomes are warranted to support those conclusions.

Mixed Valvular Disease Following Transcatheter Aortic Valve Replacement: Quantification and Systematic Differentiation Using Clinical Measurements and Image-Based Patient-Specific In Silico Modeling

Background

Mixed valvular disease (MVD), mitral regurgitation (MR) from pre‐existing disease in conjunction with paravalvular leak (PVL) following transcatheter aortic valve replacement (TAVR), is one of the most important stimuli for left ventricle (LV) dysfunction, associated with cardiac mortality. Despite the prevalence of MVD, the quantitative understanding of the interplay between pre‐existing MVD, PVL, LV, and post‐TAVR recovery is meager.

Methods and Results

We quantified the effects of MVD on valvular‐ventricular hemodynamics using an image‐based patient‐specific computational framework in 72 MVD patients. Doppler pressure was reduced by TAVR (mean, 77%; N=72; P<0.05), but it was not always accompanied by improvements in LV workload. TAVR had no effect on LV workload in 22 patients, and LV workload post‐TAVR significantly rose in 32 other patients. TAVR reduced LV workload in only 18 patients (25%). PVL significantly alters LV flow and increases shear stress on transcatheter aortic valve leaflets. It interacts with mitral inflow and elevates shear stresses on mitral valve and is one of the main contributors in worsening of MR post‐TAVR. MR worsened in 32 patients post‐TAVR and did not improve in 18 other patients.

Conclusions

PVL limits the benefit of TAVR by increasing LV load and worsening of MR and heart failure. Post‐TAVR, most MVD patients (75% of N=72; P<0.05) showed no improvements or even worsening of LV workload, whereas the majority of patients with PVL, but without that pre‐existing MR condition (60% of N=48; P<0.05), showed improvements in LV workload. MR and its exacerbation by PVL may hinder the success of TAVR.