Effect of Transcatheter Aortic Valve Replacement on the Mitral Valve Apparatus and Mitral Regurgitation

Natural History of Mitral Regurgitation After Transcatheter Aortic Valve Implantation

BACKGROUND

This study sought to determine the impact of mitral regurgitation (MR) on outcomes after transcatheter aortic valve implantation (TAVI).

METHODS

This was an observational study of TAVI for aortic stenosis (AS) from November 2012 to December 2021; 25% of patients were excluded because post-TAVI echocardiograms were unavailable. Excluded patients had a higher Society of Thoracic Surgeons predicted risk of mortality score than included patients (5.6% vs 4.9%). Patients were dichotomized according to the severity of pre-TAVI MR: < moderate vs ≥ moderate.

RESULTS

A total of 2250 patients underwent TAVI, of whom 329 (14.6%) had MR ≥ moderate before TAVI. Baseline MR ≥ moderate was associated with reduced survival (46.2% for MR ≥ moderate vs 58.7% for MR < moderate; P < .001) and a higher incidence of heart failure readmission at 5 years after TAVI; 11% of patients had progression or persistence of MR ≥ moderate at 1 year after TAVI, which was also associated with reduced survival. On multivariable logistic regression, increasing age, women, lower ejection fraction, prior acute coronary syndrome, concomitant aortic insufficiency ≥ moderate, low-flow low-gradient AS, pulmonary hypertension, baseline tricuspid regurgitation ≥ moderate, and lower mean pre-TAVI aortic transvalvular pressure gradient were associated with progression or persistence of MR ≥ moderate at 1 year after TAVI, whereas procedural variables and postprocedural complications were not.

CONCLUSIONS

Significant MR before and after TAVI was associated with reduced survival. Whereas various clinical variables were associated with significant MR after TAVI, periprocedural variables were not. Evolution of MR must be carefully surveilled after TAVI, and more data are needed to establish guidelines for managing mixed AS and MR.

The Impact of Concomitant Mitral Regurgitation on Echocardiography Parameters After TransCatheter Aortic Valve Replacement: A Systematic Review and Meta-Analysis

BACKGROUND

Mitral regurgitation (MR) commonly coexists with aortic stenosis (AS) and is a potential risk factor influencing outcomes following transcatheter aortic valve replacement (TAVR). This meta-analysis aimed to evaluate the mean changes in key echocardiographic parameters before and after TAVR and to compare these changes between patients with moderate-to-severe MR (MR ≥ 2) and those with none-to-mild MR (MR < 2).

METHODS

A comprehensive literature search was conducted using six electronic databases. We included studies that evaluated patients undergoing TAVR, classified them based on baseline MR grade ≥ 2 (moderate/severe MR) or MR grade < 2 (none/mild MR), and reported the mean difference (MD) in echocardiographic parameters before and after TAVR in both groups. The primary outcomes included changes in ejection fraction (EF), LV end-diastolic volume (LVEDV) index, LV end-systolic volume (LVESV) index, LV end-diastolic diameter (LVEDD), LV end-systolic diameter (LVESD), aortic valve area (AVA), and the mean aortic gradient. Pooled MDs were analyzed using a random-effects model.

RESULTS

Thirteen studies with 7163 patients were included, of which 2376 had an MR ≥ 2. The MR < 2 and MR ≥ 2 groups experienced significant improvements in AVA and reductions in mean aortic gradient, LVEDV index, LVESV index, LVEDD, and LVESD. Compared to MR < 2 patients, those with MR ≥ 2 exhibited significantly greater improvements in EF (MD = 2.03; 95% CI: 0.81, 3.24), LVEDV index (MD = -5.55; 95% CI: -7.85, -3.26), LVESV index (MD = -5.43; 95% CI: -7.28, -3.58), LVESD (MD = -2.23; 95% CI: -3.71, -0.26), and mean aortic gradient (MD = 1.43; 95% CI: 0.79, 2.07). However, the changes in LVEDD and AVA were not significantly different between the groups.

CONCLUSIONS

These findings suggest that patients with moderate-to-severe baseline MR before TAVR showed greater pronounced improvements in specific echocardiographic parameters related to LV function and geometry, particularly in LVEF, LVEDV index, LVESV index, and LVESD, compared to those with none-to-mild MR. Future studies should focus on stratifying outcomes according to MR etiology and using advanced imaging techniques to delineate better the mechanisms underlying these improvements.

Perioperative Outcomes in Patients Undergoing Transcatheter Aortic Valve Replacement with Concomitant Mitral Regurgitation: A Meta-Analysis

Transcatheter aortic valve replacement (TAVR) is widely performed in high-risk patients with severe aortic stenosis. However, the effects of baseline concomitant mitral regurgitation (MR) on perioperative outcomes remain unclear. This study evaluated the impact of concomitant MR severity on short-term TAVR outcomes. A systematic search of 6 electronic databases was conducted. Studies that stratified patients based on MR severity (MR ≥2 vs. <2 or MR ≥3 vs. <3) and reported perioperative outcomes, including short-term mortality, in-hospital mortality, acute kidney injury (AKI), pacemaker implantation, bleeding, vascular complications, and MR improvement (up to 1 week and 1 month) were eligible. Data from 26 studies (32,453 patients) demonstrated that patients with baseline moderate-to-severe MR (MR ≥2) had a 49% (95% confidence interval (CI), 1.32-1.70) increased risk of short-term mortality, a 41% (95% CI, 1.22-1.63) higher risk of in-hospital mortality, and a 38% (95% CI, 1.17-1.62) higher risk of AKI than those with none-to-mild MR (MR<2). Patients with an MR ≥3 had an even greater 72% (95% CI, 1.37-2.16) increase in short-term mortality. No significant differences were observed in pacemaker implantation, bleeding, or vascular complications between groups. Additionally, after TAVR, MR improved in 36% of patients by at least 1 grade within 1 week, increasing to 44% by 1 month. In TAVR patients, MR ≥2 was associated with significantly higher early mortality and AKI risk, underscoring the need for a comprehensive perioperative risk assessment. Future studies should examine the differential impact of functional and degenerative MR.

The impact of transcatheter aortic valve implantation (TAVI) on mitral regurgitation - a single center study

BACKGROUND

The coexistence of mitral regurgitation (MR) and severe aortic stenosis (AS) has been associated with worse outcomes in patients undergoing transcatheter aortic valve implantation (TAVI). Herein, the aim was to assess the etiology and degree of MR in an unselected TAVI population and investigate the impact of MR reduction at mid-term follow-up.

METHODS

Patients subjected to TAVI as a treatment for severe AS in a single center were retrospectively analyzed. The primary endpoint was the MR reduction after TAVI. The secondary endpoint was all-cause mortality and heart failure hospitalization at a 3-year follow-up.

RESULTS

Patients undergoing TAVI (n = 283) in the years 2017-2019 were screened for the presence of hemodynamically significant MR. Sixty-nine subjects (24.4%) with severe (16, 23.2%) and moderate (53, 76.8%) MR were included. The primary MR was predominant (39 subjects, 56.5%). The median age of the patients was 82 years. MR improved in 25 patients (36.2%, p < 0.001). Baseline severe MR was more prone to reduce (8 subjects, 50%) than moderate (17 subjects, 32.1%, p = 0.04). The primary MR improved in 14 patients (35.9%), while secondary in 11 patients (36.7%, p = 1). Patients showing MR reduction had lower mortality (8 vs. 29.55%, p = 0.047) and were less frequently hospitalized (20 vs. 45.45%, p = 0.03) at 3-year follow-up.

CONCLUSIONS

Hemodynamically significant MR improves after TAVI regardless of its etiology. Moreover, MR reduction after TAVI is associated with better clinical outcomes.

Mitral complex geometric changes aggravate mitral stenosis after transcatheter aortic valve replacement

Severe aortic valve stenosis (AS) often coexists with mitral valve stenosis (MS). MS aggravation after transcatheter aortic valve replacement (TAVR) is common, and its etiology is multifactorial. We hypothesized that geometric changes in the mitral complex (mitral valvular and annular deformities) are adjunctive factors aggravating MS after TAVR, particularly in older adults with a smaller left ventricle (LV). This study aimed to evaluate the mitral complex geometric changes before and after TAVR and to assess the important predictors of MS aggravation after TAVR. This retrospective study enrolled consecutive adult patients who underwent TAVR and surgical AVR (SAVR) for severe AS. The mitral valve area (MVA), the angle between the anterior mitral valve leaflet (AMVL) and left ventricular outflow tract (LVOT), AMVL length, mitral annular diameter, presence of mitral annular calcification, and LV size were evaluated using transthoracic echocardiography. This study included 258 patients who underwent TAVR and SAVR. MVA index decreased from 2.3 ± 0.6 cm² to 1.9 ± 0.5 cm² in the TAVR group. The angle between the AMVL and LVOT was 56.3 ± 9.7° preoperatively and increased to 67.3 ± 11.5° after TAVR. In multivariate analysis, the most important predictive factors of MS aggravation after TAVR were a smaller mitral annular diameter, restricted AMVL mobility, and implantation depth (odds ratio: 4.5, 5.3,3.0; 95% confidence interval: 1.6-14, 1.9-17, 1.0-8.9; and p = 0.005, p = 0.001, p = 0.042, respectively). The reduction in MVA after TAVR was related to the restriction of AMVL opening, depth of implantation and narrowing of the mitral annulus.

Combined Significant Aortic Stenosis and Mitral Regurgitation: Challenges in Timing and Type of Intervention

In this narrative review, we aim to summarize the literature surrounding the assessment and management of the common, yet understudied combination of aortic stenosis (AS) and mitral regurgitation (MR), the components of which are complexly inter-related and interdependent from diagnostic, prognostic, and therapeutic perspectives. The hemodynamic interdependency of AS and MR confounds the assessment of the severity of each valve disease, thus underscoring the importance of a multimodal approach integrating valvular and extravalvular indicators of severity. A large body of literature suggests that baseline MR is associated with reduced survival post aortic valve (AV) intervention and that regression of MR post-AV intervention confers a mortality benefit. Functional MR is more likely to regress after AV intervention than primary MR. The respective natural courses of the 2 valve diseases are not synchronized; therefore, significant AS and MR at or above the respective threshold for intervention might not coincide. Surgery is primarily a 1-stop-shop procedure because of a considerable perioperative risk of repeat interventions, whereas transcatheter treatment modalities allow for a more tailored timing of intervention with reassessment of concomitant MR after AV replacement and a potential staged intervention in the absence of MR regression. In summary, AS and MR, when combined, are interlaced into a complex hemodynamic, diagnostic, and prognostic synergy, with important therapeutic implications. Contemporary approaches should consider stepwise intervention by exploiting the advantage of transcatheter options. However, evidence is needed to demonstrate the efficacy of different timing and therapeutic options.

Clinical impact of baseline mitral regurgitation on outcomes after transcatheter aortic valve replacement for severe aortic stenosis

Objective

The clinical impact of baseline mitral regurgitation (MR) on the outcomes after transcatheter aortic valve replacement (TAVR) is not clear. This study sought to assess the clinical impact of baseline MR on outcomes after TAVR.

Methods

The study was a retrospective analysis. Data was from 120 consecutive patients with severe aortic stenosis (AS) undergoing TAVR at our center from June 2018 and July 2020. Clinical outcomes were assessed at 30-day, 1- and 2-year follow-up.

Results

The median follow-up was 736.0 (interquartile range, 666.0-965.0) days. Overall survival in patients with nonsignificant and significant baseline MR was not significantly different, while patients from the improved MR group after TAVR demonstrated a significantly higher survival than unchanged or worsened MR group during 2-year follow-up. NYHA functional class had generally improved at 1 year, with only 8.3 % of patients with nonsignificant MR and 17.5 % of patients with significant MR in class III or IV. Patients with improved MR at 1 year after TAVR had a significantly higher LVEF, smaller LVEDD and LVESD than those with unchanged or worsened MR. Among the significant baseline MR group, 70.4 % and 80.0 % of patients had improved to nonsignificant MR at 30-day and 1-year follow-up after TAVR, respectively.

Conclusions

Significant baseline MR was not associated with the increased risk of all-cause mortality 2 years after TAVR. Significant baseline MR was improved in most patients at 1 year after TAVR. Patients with unchanged or worsened MR had an increased all-cause mortality.

Three-Dimensional Transesophageal Echocardiography in Percutaneous Catheter-Based Cardiac Interventions

Cardiac structural and valve interventions have remained surgical procedures for several decades. The ability to directly visualize the region of interest during surgery made imaging of these structures pre- and postsurgery a secondary tool to compliment surgical visualization. The last two decades, however, have seen rapid advances in catheter-based percutaneous structural heart interventions (SHIs). Due to the "blind" nature of these interventions, imaging plays a crucial role in the success of these procedures. Fluoroscopy is used universally in all percutaneous cardiac SHIs and helps primarily in the visualization of catheters and devices. However, success of these procedures requires visualization of intracardiac soft tissue structures. Due to its portable nature and rapid ability to show cardiac structures online, transesophageal echocardiography (TEE) has become an integral tool for guidance for all percutaneous SHI. Transcatheter aortic valve replacement-one of the earliest catheter-based procedures-while initially dependent on TEE, has largely been replaced by preprocedural cardiac CT for accurate assessment of valve sizing. Developments in echocardiography now allow live three-dimensional (3D) visualization of cardiac structures mimicking surgical anatomy during TEE. Besides showing actual 3D intracardiac structures, 3D-TEE allows visualization of the interaction of intracardiac catheters and devices with soft tissue cardiac structures, thereby becoming a "second pair of eyes" for the operator. Real-time 3D-TEE now plays an important role complementing multiplane two dimensional and biplane TEE during such interventions. In this review, we discuss the incremental role of 3D-TEE during various SHIs performed today.

The Common Combination of Aortic Stenosis with Mitral Regurgitation: Diagnostic Insight and Therapeutic Implications in the Modern Era of Advanced Echocardiography and Percutaneous Intervention

The combination of aortic stenosis (AS) and mitral regurgitation (MR) is common in patients with degenerative valvular disease. It is characterized by having complex pathophysiology, leading to potential diagnostic pitfalls. Evidence is scarce in the literature to direct the diagnostic framework and treatment of patients with this particular combination of multiple valvular diseases. In this complex scenario, the appropriate use of advanced echocardiography and multimodality imaging methods plays a central role. Transcatheter mitral valve replacement or repair and transcatheter aortic valve replacement widen the surgical options for valve diseases. Therefore, there is an increasing need to reconsider the function, timing, and mode intervention for patients with a combination of AS with MR towards more personalized treatment.

Transcatheter Treatment of Residual Significant Mitral Regurgitation Following TAVR: A Multicenter Registry

OBJECTIVES

The aim of this study was to describe baseline characteristics, and periprocedural and mid-term outcomes of patients undergoing transcatheter mitral valve interventions post-transcatheter aortic valve replacement (TAVR) and examine their clinical benefit.

BACKGROUND

The optimal management of residual mitral regurgitation (MR) post-TAVR is challenging.

METHODS

This was an international registry of 23 TAVR centers.

RESULTS

In total, 106 of 24,178 patients (0.43%) underwent mitral interventions post-TAVR (100 staged, 6 concomitant), most commonly percutaneous edge-to-edge mitral valve repair (PMVR). The median interval post-TAVR was 164 days. Mean age was 79.5 ± 7.2 years, MR was >moderate in 97.2%, technical success was 99.1%, and 30-day device success rate was 88.7%. There were 18 periprocedural complications (16.9%) including 4 deaths. During a median follow-up of 464 days, the cumulative risk for 3-year mortality was 29.0%. MR grade and New York Heart Association (NYHA) functional class improved dramatically; at 1 year, MR was moderate or less in 90.9% of patients (mild or less in 69.1%), and 85.9% of patients were in NYHA functional class I/II. Staged PMVR was associated with lower mortality versus medical treatment (57.5% vs. 30.8%) in a propensity-matched cohort (n = 156), but this was not statistically significant (hazard ratio: 1.75; p = 0.05).

CONCLUSIONS

For patients who continue to have significant MR, remain symptomatic post-TAVR, and are anatomically suitable for transcatheter interventions, these interventions are feasible, safe, and associated with significant improvement in MR grade and NYHA functional class. These results apply mainly to PMVR. A staged PMVR strategy was associated with markedly lower mortality, but this was not statistically significant. (Transcatheter Treatment for Combined Aortic and Mitral Valve Disease. The Aortic+Mitral TRAnsCatheter Valve Registry [AMTRAC]; NCT04031274).

Managing the patient undergoing transcatheter aortic valve replacement with ongoing mitral regurgitation

INTRODUCTION

Significant mitral regurgitation (MR) frequently coexists in patients with severe symptomatic aortic stenosis undergoing transcatheter aortic valve replacement (TAVR). These patients have worse clinical outcomes than those with non-significant MR, especially if MR persists after treatment of the aortic stenosis. The optimal treatment approach for this challenging high-risk population is not well defined.

AREAS COVERED

This review aims to present the current literature on concomitant significant MR in the TAVR population, and to provide a comprehensive algorithmic approach for clinical decision-making in this challenging cohort of patients.

EXPERT OPINION

Concomitant mitral and aortic valve disease is a complex clinical entity. An exhaustive and comprehensive assessment of patient's clinical characteristics and mitral valve anatomy and function is required in order to assess the surgical risk, predict the MR response after AVR and evaluate the feasibility of percutaneous MV treatment if necessary. Further developments in transcatheter techniques will expand the indications for double valve treatment in operable and inoperable patients with concomitant significant MR and aortic stenosis.

Frailty in patients undergoing transcatheter aortic valve replacement: prognostic value of the Geriatric Nutritional Risk Index

BACKGROUND

Malnutrition is a hallmark of frailty, is common among elderly patients, and is a predictor of poor outcomes in patients with severe symptomatic aortic stenosis (AS). The Geriatric Nutritional Risk Index (GNRI) is a simple and well-established screening tool to predict the risk of morbidity and mortality in elderly patients. In this study, we evaluated whether GNRI may be used in the risk stratification and management of patients undergoing transcatheter aortic valve replacement (TAVR).

METHODS

Patients with symptomatic severe AS (n = 953) who underwent transfemoral TAVR at the University Hospital Schleswig-Holstein Kiel, Germany, between 2010 and 2019 (development cohort) were divided into two groups: normal GNRI ≥ 98 (no nutrition-related risk; n = 618) versus low GNRI < 98 (at nutrition-related risk; n = 335). The results were validated in an independent (validation) cohort from another high-volume TAVR centre (n = 977).

RESULTS

The low-GNRI group had a higher proportion of female patients (59.1% vs. 52.1%), higher median age (82.9 vs. 81.8 years), prevalence of atrial fibrillation (50.4% vs. 40.0%), median logistic EuroSCORE (17.5% vs. 15.0%) and impaired left ventricular function (<35%: 10.7% vs. 6.8%), lower median estimated glomerular filtration rate (50 vs. 57 mL/min/1.73 m² ) and median albumin level (3.5 vs. 4.0 g/dL) compared with the normal-GNRI group. Among peri-procedural complications, Acute Kidney Injury Network (AKIN) Stage 3 was more common in the low-GNRI group (3.6% vs. 0.6%, p = 0.002). After a mean follow-up of 21.1 months, all-cause mortality was significantly increased in the low-GNRI group compared with the normal-GNRI group (p < 0.001). This was confirmed in the validation cohort (p < 0.001). Low GNRI < 98 was identified as an independent risk factor for all-cause mortality (hazard ratio 1.44, 95% CI 1.01-2.04, p = 0.043). Other independent risk factors included albumin level < median of 4.0 g/dL, high-sensitive troponin T in the highest quartile (> 45.0 pg/mL), N-terminal pro-B-type natriuretic peptide in the highest quartile (> 3595 pg/mL), grade III-IV tricuspid regurgitation, pulmonary arterial hypertension, life-threatening bleeding, AKIN Stage 3 and disabling stroke.

CONCLUSIONS

Low GNRI score was associated with an increased risk of all-cause mortality in patients undergoing TAVR, implying that this vulnerable group may benefit from improved preventive measures.

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.

Transcatheter aortic valve implantation and its impact on mitral valve geometry and function

BACKGROUND

The aim of this study was to evaluate the impact of transcatheter aortic valve implantation (TAVI) on mitral valve geometry and function.

METHODS

Eighty-four patients underwent TAVI. Forty-four (52%) patients received a balloon-expandable valve and 40 (48%) were implanted with a self-expandable valve. All patients underwent three-dimensional-volumetric transesophageal echocardiography of the mitral valve before and immediately after TAVI. A dedicated software was used for assisted semiautomatic measurement of mitral annular geometry.

RESULTS

During systole, the anterior to posterior (AP) diameter was significantly reduced after the procedure (3.4 ± 0.5 cm vs 3.2 ± 0.5 cm; P < .05). The mitral annular area (10.8 ± 2.8cm² vs 9.9 ± 2.6cm² ; P < .05) as well as the tenting area (1.6 ± 0.7 cm² vs 1.2 ± 0.6 cm² ; P < .001) measured at mid-systole were reduced after TAVI. Diastolic measures were similar. Patients treated with balloon-expandable valves showed a significantly larger reduction in the AP diameter compared to self-expandable valves (-0.25 cm vs -0.11 cm; P < .05). The reduction of the annular area was higher in the balloon-expandable group (-1.2 ± 1.59 vs -0.22 ± 1.41; P < .05). Grade of mitral regurgitation did improve or remained stable after TAVI.

CONCLUSION

TAVI significantly impacts the mitral valve and mitral annular geometry and morphology. The choice of the prosthesis (balloon- vs self-expandable) may be relevant for those changes.

3D transesophageal echocardiography in TAVR

Recently, there has been an increasingly minimalistic approach to transcatheter aortic valve replacement (TAVR), with most procedures now performed under conscious sedation without real time transesophageal echocardiography (TEE) guidance. Proponents of echo should not feel discouraged by this; it is the initial insights that were gained with procedural TEE during the early years of TAVR that have allowed the procedure's gradual maturation and sophistication. Experienced centers that have promoted extensive TAVR TEE programs continue to maximize the benefits of echocardiography in both procedural planning and execution. Critical to this is the understanding of 3D TEE, allowing the annulus to be sized accurately, relevant neighboring anatomy defined, and complications flagged. This review will outline the current application of 3D TEE in TAVR and discuss challenges and opportunities for 3D echocardiography in this field.

The Effects of Transcatheter Aortic Valve Replacement on Mitral Valve Function

The transcatheter aortic valve replacement (TAVR) procedure provides a way to treat severe aortic stenosis in the large population of patients who are not candidates for surgical aortic valve replacement. Mitral regurgitation is often concomitant to aortic stenosis in these patients due to the high pressure of the left ventricle and long-term damage to the mitral valve. Due to the proximity of the aortic valve to the mitral valve, TAVR can impact the functional status of the mitral valve by affecting left ventricular outlet obstruction and the mitral valve annular shape. As TAVR becomes increasingly prevalent to treat aortic stenosis, consideration into the impact of TAVR on mitral valve function is important in order determine whether patients will be able to undergo mitral valve repair or replacement, whether surgically or percutaneously. In this review, we seek to explore the effect of TAVR on the mitral annular geometry, mitral valve flow, and the impact of TAVR on the mitral valve in the presence of mitral annular calcification.

The Impact of Self-Expandable Transcatheter Aortic Valve Replacement on Concomitant Functional Mitral Regurgitation: A Comprehensive Engineering Analysis

Background

Mitral regurgitation (MR) is present in a large proportion of patients who undergo transcatheter aortic valve replacement (TAVR). However, existing clinical data on the impact of TAVR on early post-procedural MR severity are contradictory. Using a comprehensive computational engineering methodology, this study aimed to evaluate quantitatively the structural and hemodynamic impact of TAVR on aortic-mitral continuity and MR severity in a rigorously developed and validated patient-specific left heart (LH) computer model with aortic stenosis and concomitant functional MR.

Methods

TAVR procedure was virtually simulated using a self-expandable valve (SEV) at three implantation heights. Pre- and post-TAVR LH dynamics as well as intra-operative biomechanics were analyzed.

Results

No significant differences in early MR improvement (<10%) were noted at the three implantation depths when compared to the pre-TAVR state. The high deployment model resulted in the highest stress in the native aortic leaflets, lowest stent-tissue contact force, highest aortic-mitral angle, and highest MR reduction for this patient case. When comparing SEV vs. balloon-expandable valve (BEV) performance at an optimal implantation height, the SEV gave a higher regurgitant volume ⋅ than the pre-TAVR model (40.49 vs 37.59 ml), while the BEV model gave the lowest regurgitant volume (33.84 vs 37.59 ml).

Conclusions

Contact force, aortic-mitral angle, and valve annuli compression were identified as possible mechanistic parameters that may suggest avenues for acute MR improvement. Albeit a single patient parametric study, it is our hope that such detailed engineering analysis could shed some light into the underlying biomechanical mechanisms of TAVR impact on MR.

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.

The impact of balloon-expandable transcatheter aortic valve replacement on concomitant mitral regurgitation: a comprehensive computational analysis

The aortic and mitral valves function in a reciprocal interdependent fashion. However, the impact of transcatheter aortic valve replacement (TAVR) on the aortic-mitral continuity and severity of mitral regurgitation (MR) are poorly understood. In this study, a comprehensive engineering analysis was performed to investigate the impact of TAVR on MR severity and left heart dynamics in a retrospective patient case who harbours bicuspid aortic valve stenosis and concomitant functional MR. The TAVR procedure was computer simulated using a balloon-expandable valve, and the impact of three implantation heights on aortic-mitral coupling, MR severity and device performance were analysed. The accuracy and predictability of the computer modelling framework were validated with pre- and post-operative echo data. The highest deployment model resulted in higher stresses in the native leaflets, contact radial force and stent recoil, while the midway implantation model gave better haemodynamic performance and MR reduction in this patient case. Although the regurgitant volume decreased (less than 10%) for the three deployment configurations, no significant differences in MR severity improvement and mitral leaflet tethering were found. Acute improvement in MR was (i) due to the mechanical compression of the stent against the aortic-mitral curtain, (ii) due to an immediate drop in the ventricular pressure and transmitral pressure gradient. Albeit a single real clinical case, it is our hope that such detailed engineering computational analysis could shed light on the underlying biomechanical mechanisms of TAVR impact on MR.

Transcatheter Aortic Valve Replacement and Concomitant Mitral Regurgitation

Mitral regurgitation frequently coexists in patients with severe aortic stenosis. Patients with moderate to severe mitral regurgitation at the time of transcatheter aortic valve replacement are at increased risk of future adverse events. Whether concomitant mitral regurgitation is independently associated with worse outcomes after TAVR remains a matter of debate. The optimal therapeutic strategy in these patients-TAVR with evidence-based heart failure therapy, combined TAVR and transcatheter mitral valve intervention, or staged transcatheter therapies-is ill-defined, and guideline-based recommendations in patients at increased risk for open heart surgery are lacking. Hence, a thorough evaluation of the aortic and mitral valve anatomy and function, along with an in-depth assessment of the patients' baseline risk profile, provides the basis for an individualized treatment approach. The aim of this review is therefore to give an overview of the current literature on mitral regurgitation in TAVR, focusing on different diagnostic and therapeutic strategies and optimal clinical decision making.

Successful Treatment of Mitral Regurgitation after Transapical Transcatheter Aortic Valve Implantation by Percutaneous Edge-to-edge Mitral Valve Repair (MitraClip®) -The First Combination Therapy Performed in Japan

A 75-year old man with a history of inferior myocardial infarction was admitted with symptoms of progressive heart failure 3 months after undergoing transapical transcatheter aortic valve implantation (TAVI). Echocardiography revealed severe mitral regurgitation (MR) caused by posterior leaflet tethering, without traumatic injury of the mitral valve or chordae. The patient was successfully treated by percutaneous edge-to-edge mitral valve repair (MitraClip^®). This case highlights the role of MitraClip^® in high-risk patients suffering from MR, and suggests that apical contractile loss or adhesion caused by apical puncture and suturing in transapical TAVI may be one of the mechanisms of worsening MR.

Association of postprocedural aortic regurgitation with mitral regurgitation worsened after transcatheter aortic valve replacement

BACKGROUND

There is a paucity of investigation which demonstrates a predictor of mitral regurgitation (MR) worsened after aortic valve replacement (TAVR).

AIM

The aim of this study was to identify the predictor of worsened MR after transcatheter TAVR.

METHODS

We retrospectively studied a total of 209 patients with mild or less MR at baseline who underwent TAVR for the treatment of severe aortic stenosis with the balloon-expandable device. We found the presence of MR worsened after TAVR in 6% (12 patients) of all patients. Moderate or more postprocedural aortic regurgitation (AR) (odds ratio, 8.104; 95% confidence interval, 1.78-36.87; P = .007) was identified as a predictor of MR worsening after TAVR. In-hospital outcomes indicated that patients within whom MR worsened suffered congestive heart failure more than those with unchanged or improved MR after TAVR (P < .05).

CONCLUSION

Significant postprocedural AR was associated with MR worsened from mild or less to moderate or more after TAVR. Worsened MR might affect in-hospital congestive heart failure.

Echocardiographic follow-up after transcatheter aortic valve replacement

The use of transcatheter aortic valve replacement (TAVR) for high-risk patients with aortic stenosis has rapidly increased during the past years. Accordingly, more and more patients are referred for a follow-up echocardiographic study after TAVR. However, the echocardiographic evaluation of patients who underwent TAVR places specific demands on echocardiographers. Furthermore, TAVR may be associated with new types of complications, which are frequently unrecognized or underestimated due to lack of familiarity with the normal and pathological appearance of TAVR. Therefore, this review summarizes the echocardiographic parameters describing the structural and functional status of bioprostheses used in TAVR, procedures taking into account their peculiar hemodynamics. We also describe the strengths and the limitations of echocardiography and of other imaging modalities in detecting long-term complications of TAVR (eg, infective endocarditis, thrombosis). The aim of this review was to serve as a guide for a structured echocardiographic follow-up of TAVR patients, as well as for the echocardiographic diagnosis of the procedure-associated complications.

Role of echocardiography for catheter-based management of valvular heart disease

Catheter-based treatment of valvular heart disease, such as transvalvular aortic valve replacement (TAVR) or mitral clip procedure, has been increasingly accepted as a treatment choice for the past several years. Such new treatment options have been changing the management of patients with valvular heart disease drastically while socio-economic factors regarding their application need to be taken into consideration. The use of echocardiography, including transesophageal echocardiography (TEE), for such catheter-based treatments is essential for the success of the procedures. Severe hypotension after TAVR is a life-threatening emergency. Rapid assessment and diagnosis in the catheterization or hybrid laboratory is essential for safety and a positive outcome. Possible diagnoses in this critical situation would include severe left ventricular dysfunction due to coronary obstruction, cardiac tamponade, aortic rupture, acute severe aortic and/or mitral valve regurgitation, and hypovolemia due to bleeding. Although new types of TAVR valves reduce para-valvular aortic regurgitation (AR) significantly, it is still important to judge the severity of para-valvular AR correctly in the laboratory. As for mitral clip procedure, TEE is vital for guiding and monitoring the entire process. Accurate identification of the location and the geometry of the regurgitant orifice is necessary for proper placement of the clip. Real-time 3D TEE provides helpful en face view of the mitral valve and clip together to this end. Residual mitral regurgitation (MR) after the first clip is not uncommon. Quick and precise imaging of the residual MR (location and severity) with TEE is extremely important for the interventionist to place the second clip and possibly third clip properly. After the completion of the clip procedure, mitral valve stenosis and also iatrogenic atrial septal defect need to be checked by TEE. Echocardiography, especially TEE, is also vital for the success of other newer trans-catheter procedures such as device closure of para-valvular MR of the artificial valve, valve in valve procedure, and native valve replacement.

Impact of baseline mitral regurgitation on short- and long-term outcomes following transcatheter aortic valve replacement

BACKGROUND

The prevalence of concomitant significant mitral regurgitation (MR) in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) ranges from 2% to 33%. The impact of significant MR on post-TAVR outcomes remains controversial.

METHODS

The data from a cohort of patients with symptomatic severe AS undergoing TAVR at out institution were retrospectively analyzed. The last transthoracic echocardiogram (TTE) before the index TAVR procedure was selected as the baseline assessment of the degree of MR. The total study cohort (N = 589) was divided into 2 groups: significant ≥moderate MR (n = 68) versus nonsignificant <moderate MR (n = 521) at baseline. The 2 groups were compared in regard to baseline, imaging, procedural, and postprocedural characteristics. In-hospital, 30-day, and 1-year outcomes were assessed. Multivariate Cox regression survival analyses were performed to test the independent effect of ≥moderate MR on mortality at short- and long-term follow-up periods.

RESULTS

Patients with ≥moderate MR had a higher mortality rate versus patients with <moderate MR during the initial 30-day follow-up after TAVR (unadjusted log-rank P = .011, risk-adjusted P = .031, hazard ratio = 2.40, 95% CI 1.08-5.29). However, the mortality rates at 1-year follow-up postprocedure were similar between the 2 groups (unadjusted log-rank P = .553, risk-adjusted P = .331, hazard ratio = 0.70, 95% CI 0.35-1.43). Among the original ≥moderate group, 62.5% and 77.7% of patients had improved to <moderate MR at 30-day and 1-year follow-up, respectively.

CONCLUSIONS

Moderate or greater MR in patients undergoing TAVR is associated with a higher 30-day but not 1-year mortality. A majority of the patients demonstrated significant improvement in MR following TAVR.

Impact of Functional Versus Organic Baseline Mitral Regurgitation on Short- and Long-Term Outcomes After Transcatheter Aortic Valve Replacement

The impact of the specific etiology of mitral regurgitation (MR) on outcomes in the transcatheter aortic valve replacement (TAVR) population is unknown. This study aimed to evaluate the longitudinal changes in functional versus organic MR after TAVR in addition to their impact on survival. Consecutive patients who underwent TAVR from May 2007 to May 2015 who had baseline significant (moderate or greater) MR were included. Transthoracic echocardiography was used to evaluate the cohort at baseline, post-procedure, 30-day, 6-month, and 1-year follow-up. The primary outcomes included mortality at 30 days and 1 year. Longitudinal, mixed-model regression analyses were performed to assess the differences in the magnitude of longitudinal changes of MR, left ventricular (LV) ejection fraction, and New York Heart Association functional class. Seventy patients (44% men, mean 83 years) with moderate or greater MR at baseline (30 functional vs 40 organic) were included, with the functional group having a statistically significant mean younger age and higher rates of previous coronary artery bypass grafting. Kaplan-Meier cumulative mortality rates were similar: 30 days (10% vs 17.5%, unadjusted log-ranked p = 0.413) and 1 year (29.4% vs 23.2%, unadjusted log-ranked p = 0.746) in the functional versus organic MR groups, respectively. There were greater degrees of short- and long-term improvement in MR severity (slope difference p = 0.0008), LV ejection fraction (slope difference p = 0.0009), and New York Heart Association class (slope difference p = 0.0054) in the functional versus organic group. In conclusion, patients with significant functional versus organic MR who underwent TAVR have similar short- and long-term survival; nevertheless, those with a functional origin are more likely to have significant improvements in MR severity, LV-positive remodeling, and functional class. These findings may help strategize therapies for MR in patients with combined aortic and mitral valve disease who are undergoing TAVR.

Recent advances in echocardiography for valvular heart disease

Echocardiography is the imaging modality of choice for the assessment of patients with valvular heart disease. Echocardiographic advancements may have particular impact on the assessment and management of patients with valvular heart disease. This review will summarize the current literature on advancements, such as three-dimensional echocardiography, strain imaging, intracardiac echocardiography, and fusion imaging, in this patient population.

Meta-analysis of mortality outcomes and mitral regurgitation evolution in 4,839 patients having transcatheter aortic valve implantation for severe aortic stenosis

Transcatheter aortic valve implantation (TAVI) is an effective alternative therapy in selected patients with severe aortic stenosis. The role and effects of coexistent moderate to severe mitral regurgitation (msMR) in patients who undergo TAVI remain unclear. Thirteen studies enrolling 4,839 patients who underwent TAVI, including patients with msMR, were considered in a meta-analysis and analyzed for all-cause-mortality; a further meta-analysis was performed to assess mitral regurgitation (MR) evolution after TAVI. In patients with msMR, all-cause-mortality after TAVI was significantly increased at 30-day (effect size [ES] -0.18, 95% confidence interval [CI] -0.31 to -0.04, I(2) = 46.51, Q = 7.48), 1-year (ES -0.22, 95% CI -0.36 to -0.08, I(2) = 56.20, Q = 11.41), and 2-year (ES -0.15, 95% CI -0.27 to -0.02, I(2) = 0.00, Q = 2.64) follow-up compared with patients with absent or mild MR, independent of baseline left ventricular ejection fraction. Interestingly, the impact of msMR on outcomes was statistically stronger when the CoreValve system was used. TAVI was also associated with an improvement in MR entity at 3- and 6-month follow-up (overall ES -0.19, 95% CI -0.37 to -0.01, I(2) = 61.52, Q = 10.39). In conclusion, the presence of preoperative msMR in patients with severe, symptomatic aortic stenosis who undergo TAVI negatively affects outcomes after TAVI. In addition, in the same group of patients, a trend toward a reduction in MR severity was observed. Whether the decrease in MR severity affects mortality after TAVI remains to be defined.