Predictors of left ventricular reverse remodeling after percutaneous therapy for mitral regurgitation with the MitraClip system

Predictors of Improvement in Concomitant Tricuspid Regurgitation Following Transcatheter Edge-to-Edge Mitral Valve Repair

BACKGROUND

Improvement in concomitant tricuspid regurgitation (TR) after mitral valve transcatheter edge-to-edge repair (M-TEER) for mitral regurgitation (MR) occurs frequently; however factors determining the post-procedural course of TR are not well understood. We investigated the parameters associated with TR improvement after M-TEER.

METHODS AND RESULTS

A total of 300 patients were consecutively included in this retrospective analysis. MR and TR severity as well as heart chamber metrics were assessed before the procedure and at follow-up. Device success was achieved in 97.3% of patients. TR decreased in 30.2% of patients. Patients with improved TR were more often female, had more severe TR at baseline, and their right heart dimensions at baseline trended to be smaller. Female sex (odds ratio (OR) 2.997), baseline MR-Grade (OR 3.181) and baseline TR-Grade (OR 2.653) independently predicted TR reduction. More pronounced right heart reverse remodeling was observed in patients with improved TR. TR regression independently predicted lower mortality (hazard ratio (HR) 0.333, 95% confidence interval 0.112-0.996, p = 0.049).

CONCLUSIONS

A reduction in concomitant TR severity after M-TEER occurred mainly in females and in patients with high-grade TR and MR at baseline. TR regression is associated with better survival after M-TEER.

A review of biomarker and imaging monitoring to predict heart failure recovery

Heart failure is a clinical syndrome caused by structural cardiac abnormalities that lead to increased intracardiac pressures and decreased cardiac output. Following cardiovascular insult or direct myocardial injury, neurohormonal activation triggers hemodynamic changes and cardiac remodeling to preserve cardiac output. While initially adaptive, cardiac remodeling eventually causes pathologic changes in cardiac structure that often compromise cardiac function. Reverse remodeling is the regression of abnormal cardiac chamber geometry and function after myocardial injury. In recent years, several classes of therapeutics have been associated with greater likelihood of reverse remodeling. Heart failure recovery and heart failure remission, terms encompassing the clinical correlates of reverse remodeling, have been associated with improved survival in patients with heart failure with reduced ejection. As such, identifying predictors of heart failure recovery can have important implications for guiding clinical practice and therapeutic innovation. This review addresses the role of biomarkers and imaging monitoring in predicting structural, functional, and clinical recovery in patients with acute and chronic heart failure.

Effect of transcatheter edge-to-edge repair device position on diastolic hemodynamic parameters: An echocardiography-based simulation study

Background

Transcatheter edge-to-edge repair (TEER) has developed from innovative technology to an established treatment strategy of mitral regurgitation (MR). The risk of iatrogenic mitral stenosis after TEER is, however, a critical factor in the conflict of interest between maximal reduction of MR and minimal impairment of left ventricular filling. We aim to investigate systematically the impact of device position on the post treatment hemodynamic outcome by involving the patient-specific segmentation of the diseased mitral valve.

Materials and methods

Transesophageal echocardiographic image data of ten patients with severe MR (age: 57 ± 8 years, 20% female) were segmented and virtually treated with TEER at three positions by using a position based dynamics approach. Pre- and post-interventional patient geometries were preprocessed for computational fluid dynamics (CFD) and simulated at peak-diastole with patient-specific blood flow boundary conditions. Simulations were performed with boundary conditions mimicking rest and stress. The simulation results were compared with clinical data acquired for a cohort of 21 symptomatic MR patients (age: 79 ± 6 years, 43% female) treated with TEER.

Results

Virtual TEER reduces the mitral valve area (MVA) from 7.5 ± 1.6 to 2.6 ± 0.6 cm2. Central device positioning resulted in a 14% smaller MVA than eccentric device positions. Furthermore, residual MVA is better predictable for central than for eccentric device positions (R2 = 0.81 vs. R2 = 0.49). The MVA reduction led to significantly higher maximal diastolic velocities (pre: 0.9 ± 0.2 m/s, post: 2.0 ± 0.5 m/s) and pressure gradients (pre: 1.5 ± 0.6 mmHg, post: 16.3 ± 9 mmHg) in spite of a mean flow rate reduction by 23% due to reduced MR after the treatment. On average, velocities were 12% and pressure gradients were 25% higher with devices in central compared to lateral or medial positions.

Conclusion

Virtual TEER treatment combined with CFD is a promising tool for predicting individual morphometric and hemodynamic outcomes. Such a tool can potentially be used to support clinical decision making, procedure planning, and risk estimation to prevent post-procedural iatrogenic mitral stenosis.

Changes in renin-angiotensin-aldosterone system during cardiac remodeling after mitral valvuloplasty in dogs

BACKGROUND

Information regarding changes in renin-angiotensin-aldosterone system (RAAS) during cardiac remodeling after mitral valvuloplasty (MVP) in dogs remains lacking.

HYPOTHESIS/OBJECTIVES

To assess the longitudinal effects of MVP on circulating RAAS activity.

ANIMALS

Eight client-owned dogs receiving MVP for myxomatous mitral valve disease (MMVD).

METHODS

This is a cohort study. Plasma renin activity (PRA), angiotensin II (AT2), aldosterone (PAC), blood urea nitrogen (BUN), and creatinine concentrations, were measured in these dogs before (baseline) and at 3 consecutive monthly follow-ups (Post-1M, Post-2M, Post-3M). Echocardiography was concomitantly used to assess the process of cardiac recovery after MVP.

RESULTS

The echocardiography revealed a significant decrease in LVIDDN, LA/Ao, FS, E velocity, E/A, E' sep, S' lat, E' lat, and A' lat after MVP compared with baseline (P < .05). There was a significant reduction in the PRA (2.45, 3.05, 2.74 vs 8.8 ng/mL/h; P = .002), AT2 (466, 315, 235 vs 1200 pg/mL; P = .009), and PAC (39.88, 47, 54.62 vs 179.5 pg/mL; P = .01), respectively at Post-1M, Post-2M, Post-3M compared to the baseline. Additionally, BUN and creatinine concentrations decreased from Post-1M. The RAAS variables showed significant, weak to moderate, relationship with selected echocardiographic variables.

CONCLUSIONS AND CLINICAL IMPORTANCE

Mitral valvuloplasty contributes to decreased RAAS activity in MMVD dogs, which paralleled the process of cardiac reverse remodeling up to Post-3M. This information facilitates formulating strategies to optimize clinical outcomes for dogs after MVP.

Extent and determinants of left ventricular reverse remodeling in patients with secondary mitral regurgitation undergoing MitraClip implantation

Background

In secondary MR, data on left ventricular (LV) remodeling after MitraClip procedure are rare, even this information may impact patient selection. This study investigated changes in LV structure and function by cardiovascular magnetic resonance (CMR) following MitraClip implantation for secondary mitral regurgitation (MR) in order to assess extent and predictors of LV reverse remodeling (LVRR).

Methods and Results

Twenty-nine patients underwent CMR imaging prior to and six months after MitraClip procedure. LVRR was defined by a decrease of LV end-diastolic volume index (LVEDVi) > 15% compared to baseline. According to the definition of LVRR, 34% of patients displayed LVRR at follow-up CMR. Baseline LV stroke volume index (LVSVi), LV ejection fraction (LVEF), LV circumferential strain and MR volume at baseline were predictors of LVRR at follow-up. At second CMR, we detected an improvement in hemodynamic status as illustrated by an increase in effective LVSVi (28 ± 8 ml/m² vs. 33 ± 8 ml/m²; p = 0.053) and cardiac index (2.0 ± 0.5 vs. 2.3 ± 0.5 l/min; p = 0.016), while LVEF and LV strain parameters did not change (p > 0.05). Improvements in effective LVSVi were associated with the decrease of MR volume (r = 0.509; p = 0.018) and MR fraction (r = 0.629; p = 0.002) by MitraClip.

Conclusions

Together, MitraClip implantation is associated with LVRR in one third of patients. Baseline LV function and magnitude of MR are important predictors of LVRR. Improvement of hemodynamic status may be assessed by effective stroke volume index and correlates with the reduction of MR by MitraClip implantation, rather than an increase in LV contractility.

Selection of the Optimal Candidate to MitraClip for Secondary Mitral Regurgitation: Beyond Mitral Valve Morphology

Secondary mitral regurgitation (MR) occurs despite structurally normal valve apparatus due to an underlying disease of the myocardium leading to disruption of the balance between tethering and closing forces with ensuing failure of leaflet coaptation. In patients with heart failure (HF) and left ventricular dysfunction, secondary MR is independently associated with poor outcome, yet prognostic benefits related to the correction of MR have remained elusive. Surgery is not recommended for the correction of secondary MR outside coronary artery bypass grafting. Percutaneous mitral valve repair (PMVR) with MitraClip implantation has recently evolved as a new transcatheter treatment option of inoperable or high-risk patients with severe MR, with promising results supporting the extension of guideline recommendations. MitraClip is highly effective in reducing secondary MR in HF patients. However, the derived clinical benefit is still controversial as two randomized trials directly comparing PMVR vs. optimal medical therapy in severe secondary MR yielded virtually opposite conclusions. We reviewed current evidence to identify predictors of PMVR-related outcomes in secondary MR useful to improve the timing and the selection of patients who would derive maximal benefit from MitraClip intervention. Beyond mitral valve anatomy, optimal candidate selection should rely on a comprehensive diagnostic workup and a fine-tuned risk stratification process aimed at (i) recognizing the substantial heterogeneity of secondary MR and its complex interaction with the myocardium, (ii) foreseeing hemodynamic consequences of PMVR, (iii) anticipating futility and (iv) improving symptoms, quality of life and overall survival.