Future of transcatheter aortic valve implantation — evolving clinical indications

Syncope in Patients With Severe Aortic Stenosis Undergoing Transcatheter Aortic Valve Replacement

BACKGROUND

No data exist on the clinical and prognostic significance of syncope in patients undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis.

METHODS

A total of 1705 consecutive patients with severe aortic stenosis undergoing TAVR in a tertiary university centre between 2007 and 2021 were included and classified according to the presence of syncope before the TAVR procedure. Baseline, procedural, and follow-up data were collected prospectively in a dedicated database.

RESULTS

A total of 115 patients (7%) presented with syncope before the TAVR procedure. Of these, 15 patients (13%) showed arrhythmic episodes as the probable cause of the syncope, and all of them had pacemakers implanted at a median of 13 (6 to 53) days before the TAVR procedure. Patients with syncope were older (82 ± 8 years vs 80 ± 8 years, P = 0.001) and had a higher rate of pacemaker implantation before the TAVR procedure (27% vs 14%, P < 0.001), with no differences between groups regarding the severity of aortic stenosis (transvalvular gradient, valve area). There were no differences between groups in 30-day (adjusted hazard ratio [HR], 1.28; 95% confidence interval [CI], 0.46-3.60) and 1-year (adjusted HR, 0.71; 95% CI, 0.0.35-1.45) mortality following TAVR.

CONCLUSIONS

Syncope was not associated with a more advanced valvular disease and had no significant prognostic impact on patients undergoing TAVR. However, arrhythmias and conduction-system disturbances were more common in patients with previous syncope and might play a relevant role in the pathogenesis of syncope in patients with aortic stenosis.

A benchmark study of convolutional neural networks in fully automatic segmentation of aortic root

Recent clinical studies have suggested that introducing 3D patient-specific aortic root models into the pre-operative assessment procedure of transcatheter aortic valve replacement (TAVR) would reduce the incident rate of peri-operative complications. Tradition manual segmentation is labor-intensive and low-efficient, which cannot meet the clinical demands of processing large data volumes. Recent developments in machine learning provided a viable way for accurate and efficient medical image segmentation for 3D patient-specific models automatically. This study quantitively evaluated the auto segmentation quality and efficiency of the four popular segmentation-dedicated three-dimensional (3D) convolutional neural network (CNN) architectures, including 3D UNet, VNet, 3D Res-UNet and SegResNet. All the CNNs were implemented in PyTorch platform, and low-dose CTA image sets of 98 anonymized patients were retrospectively selected from the database for training and testing of the CNNs. The results showed that despite all four 3D CNNs having similar recall, Dice similarity coefficient (DSC), and Jaccard index on the segmentation of the aortic root, the Hausdorff distance (HD) of the segmentation results from 3D Res-UNet is 8.56 ± 2.28, which is only 9.8% higher than that of VNet, but 25.5% and 86.4% lower than that of 3D UNet and SegResNet, respectively. In addition, 3D Res-UNet and VNet also performed better in the 3D deviation location of interest analysis focusing on the aortic valve and the bottom of the aortic root. Although 3D Res-UNet and VNet are evenly matched in the aspect of classical segmentation quality evaluation metrics and 3D deviation location of interest analysis, 3D Res-UNet is the most efficient CNN architecture with an average segmentation time of 0.10 ± 0.04 s, which is 91.2%, 95.3% and 64.3% faster than 3D UNet, VNet and SegResNet, respectively. The results from this study suggested that 3D Res-UNet is a suitable candidate for accurate and fast automatic aortic root segmentation for pre-operative assessment of TAVR.

Percutaneous versus surgical approach to aortic valve replacement with coronary revascularization: A systematic review andmeta-analysis

OBJECTIVE

The optimal treatment of patients with severe aortic stenosis (AS) and complex coronary artery disease (CAD) remains controversial. We conducted a meta-analysis to investigate outcomes of transcatheter aortic valve replacement (TAVR) with percutaneous coronary intervention (PCI) versus surgical aortic valve replacement (SAVR) with coronary artery bypass grafting (CABG).

METHODS

We searched PubMed, Embase, and Cochrane databases from its inception up to 17 December 2022 for studies that assessed TAVR + PCI versus SAVR + CABG in patients with AS and CAD. The primary outcome was perioperative mortality.

RESULTS

Six observational studies including 135,003 patients assessing TAVI + PCI (n = 6988) versus SAVR + CABG (n = 128,015) were included. Compared to SAVR + CABG, TAVR + PCI was not significantly associated with perioperative mortality (RR, 0.76; 95% CI, 0.48-1.21; p = 0.25), vascular complications (RR, 1.85; 95% CI, 0.72-4.71; p = 0.20), acute kidney injury (RR, 0.99; 95% CI, 0.73-1.33; p = 0.95), myocardial infraction (RR, 0.73; 95% CI, 0.30-1.77; p = 0.49), or stroke (RR, 0.87; 95% CI, 0.74-1.02; p = 0.09). TAVR + PCI significantly reduced the incidence of major bleeding (RR, 0.29; 95% CI, 0.24-0.36; p < 0.01) and length of hospital stay (MD, -1.60; 95% CI, -2.45 to -0.76; p < 0.01), but increased the incidence of pacemaker implantation (RR, 2.03; 95% CI, 1.88-2.19; p < 0.01). At follow-up, TAVR + PCI was significantly associated with coronary reintervention (RR, 3.17; 95% CI, 1.03-9.71; p = 0.04) and a reduced rate of long-term survival (RR, 0.86; 95% CI, 0.79-0.94; p < 0.01).

CONCLUSIONS

In patients with AS and CAD, TAVR + PCI did not increase perioperative mortality, but increased the rates of coronary reintervention and long-term mortality.

Thirty-Day Readmission Rate & Healthcare Economic Effects of patients with Transcatheter Aortic Valve Replacement and Co-Existing Chronic Congestive Heart Failure

BACKGROUND

Transcatheter aortic valve replacement (TAVR) procedures have increased since adoption in 2010. Readmission for TAVR patients with underlying chronic congestive heart failure (cCHF) remains challenging. Therefore, we sought to determine the 30-day readmission rate (30-DRr) of patients who undergo TAVR & co-existing cCHF & its impact on mortality & healthcare utilization in the United States.

METHODS

We performed a retrospective study using the national readmission database year 2017 and 2018. The patients studied were discharged with TAVR as a principal diagnosis & underlying cCHF as a secondary diagnosis according to ICD-10 codes. The primary outcome was a 30-day readmission rate and mortality, while secondary outcomes were the most common diagnoses for readmission, & resource utilization.

RESULTS

A total of 76,892 index hospitalization for TAVR with co-existing cCHF: mean age was 79.7 years [SD: ± 2], & 54.5% of patients were males. In-hospital mortality rate for index admission was 1.63%. The 30-DRr was 9.5%. Among the group of readmitted patients, in-hospital mortality rate was 3.13%. Readmission mortality showed a statistically significant increase compared to index mortality (3.13% vs. 1.63%, adjusted p=<0.001, aOR: 2.1, 95% CI: 1.6-2.9). The total healthcare in-hospital economic spending was $94.4 million, and total patient charge of $412 million.

CONCLUSION

Approximately 1 in 10 patients who underwent TAVR with underlying cCHF had 30-DRr, with subsequent readmissions associated with increased healthcare spending. Readmission mortality showed a statistically significant increase when compared to index mortality. TAVR patients with cCHF are a vulnerable subset requiring additional outpatient care.

Comparative Outcomes of TAVR in Mixed Aortic Valve Disease and Aortic Stenosis: A Meta-analysis

INTRODUCTION

Transcatheter aortic valve replacement (TAVR) has become a suitable alternative to surgical aortic valve replacement (SAVR) for the treatment of symptomatic severe aortic stenosis (AS). A high proportion of patients with AS have mixed aortic valve disease (MAVD) with mild or more concurrent aortic regurgitation (AR). Differential outcomes of TAVR among patients with AS and MAVD have not been well characterized. We compared 1-year mortalities following TAVR among patients with MAVD and AS.

METHODS

We conducted a meta-analysis of studies published in PubMed/Medline. The primary outcome was 1-year all-cause mortality following TAVR among patients with MAVD vs. AS. Secondary endpoints were: (1) incidence of AR within 30 days following TAVR (post TAVR AR); and (2) 1-year all-cause mortality within each group stratified according to severity of post TAVR AR.

RESULTS

Nine studies involving 9505 participants were included in the analysis. At 1 year following TAVR, mortality was lower in MAVD than in AS; HR 0.89, 95% CI 0.81-0.98. The mortality advantage increased when pre-TAVR AR was moderate or more; HR 0.84, 95% CI 0.72-0.99. The mortality advantage was attenuated after correction for publication bias. There was a higher risk of post TAVR AR in the MAVD group; OR 1.51, 95% CI 1.20-1.90 but the impact on mortality of moderate vs. mild post TAVR AR was greater among patients with AS than in patients with MAVD HR 1.67 95% CI 0.89-3.14 vs. 0.93 95% CI 0.47-1.85.

CONCLUSIONS

Patients with MAVD have similar or improved survival 1 year after TAVR compared to those with AS.

Impact of Enterococci vs. Staphylococci Induced Infective Endocarditis after Transcatheter Aortic Valve Implantation

BACKGROUND

The two most common organisms found in infective endocarditis following transcatheter aortic valve implantation (TAVI-IE) are enterococci (EC-IE) and staphylococci (SC-IE). We aimed to compare clinical characteristics and outcomes of patients with EC-IE and SC-IE.

METHODS

TAVI-IE patients from 2007 to 2021 were included in this analysis. The 1-year mortality was the primary outcome measure of this retrospective multi-center analysis.

RESULTS

Out of 163 patients, 53 (32.5%) EC-IE and 69 (42.3%) SC-IE patients were included. Subjects were comparable with regard to age, sex, and clinically relevant baseline comorbidities. Symptoms at admission were not significantly different between groups, except for a lower risk for presenting with septic shock in EC-IE than SC-IE. Treatment was performed in 78% by antibiotics alone and in 22% of patients by surgery and antibiotics, with no significant differences between groups. The rate of any complication, in particular heart failure, renal failure, and septic shock during treatment for IE, was lower in EC-IE compared with SC-IE (p < 0.05). In-hospital (EC-IE: 36% vs. SC-IE: 56%, p = 0.035) and 1-year mortality (EC-IE: 51% vs. SC-IE: 70%, p = 0.009) were significantly lower in EC-IE compared with SC-IE.

CONCLUSIONS

EC-IE, compared with SC-IE, was associated with a lower morbidity and mortality. However, absolute numbers are high, a finding that should trigger further research in appropriate perioperative antibiotic management and improvement of early IE diagnosis in the case of clinical suspicion.

Soft robotic patient-specific hydrodynamic model of aortic stenosis and ventricular remodeling

Aortic stenosis (AS) affects about 1.5 million people in the United States and is associated with a 5-year survival rate of 20% if untreated. In these patients, aortic valve replacement is performed to restore adequate hemodynamics and alleviate symptoms. The development of next-generation prosthetic aortic valves seeks to provide enhanced hemodynamic performance, durability, and long-term safety, emphasizing the need for high-fidelity testing platforms for these devices. We propose a soft robotic model that recapitulates patient-specific hemodynamics of AS and secondary ventricular remodeling which we validated against clinical data. The model leverages 3D-printed replicas of each patient's cardiac anatomy and patient-specific soft robotic sleeves to recreate the patients' hemodynamics. An aortic sleeve allows mimicry of AS lesions due to degenerative or congenital disease, whereas a left ventricular sleeve recapitulates loss of ventricular compliance and diastolic dysfunction (DD) associated with AS. Through a combination of echocardiographic and catheterization techniques, this system is shown to recreate clinical metrics of AS with greater controllability compared with methods based on image-guided aortic root reconstruction and parameters of cardiac function that rigid systems fail to mimic physiologically. Last, we leverage this model to evaluate the hemodynamic benefit of transcatheter aortic valves in a subset of patients with diverse anatomies, etiologies, and disease states. Through the development of a high-fidelity model of AS and DD, this work demonstrates the use of soft robotics to recreate cardiovascular disease, with potential applications in device development, procedural planning, and outcome prediction in industrial and clinical settings.

Sex Differences in the Impact of Aortic Valve Calcium Score on Mortality After Transcatheter Aortic Valve Replacement

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is now an approved alternative to surgical aortic valve replacement for the treatment of severe aortic stenosis. As the clinical adoption of TAVR expands, it remains important to identify predictors of mortality after TAVR. We aimed to evaluate the impact of sex differences in aortic valve calcium score (AVCS) on long-term mortality following TAVR in a large patient sample.

METHODS

We included consecutive patients who successfully underwent TAVR for treatment of severe native aortic valve stenosis from June 2010 to May 2021 across all US Mayo Clinic sites with follow-up through July 2021. AVCS values were obtained from preoperative computed tomography of the chest. Additional clinical data were abstracted from medical records. Kaplan-Meier curves and Cox-proportional hazard regression models were employed to evaluate the effect of AVCS on long-term mortality.

RESULTS

A total of 2543 patients were evaluated in the final analysis. Forty-one percent were women, median age was 82 years (Q1: 76, Q3: 86), 18.4% received a permanent pacemaker following TAVR, and 88.5% received a balloon expandable valve. We demonstrate an increase in mortality risk with higher AVCS after multivariable adjustment (P<0.001). When stratified by sex, every 500-unit increase in AVCS was associated with a 7% increase in mortality risk among women (adjusted hazard ratio, 1.07 [95% CI, 1.02-1.12]) but not in men.

CONCLUSIONS

We demonstrate a notable sex difference in the association between AVCS and long-term mortality in a large TAVR patient sample. This study highlights the potential value of AVCS in preprocedural risk stratification, specifically among women undergoing TAVR. Additional studies are needed to validate this finding.

Utilizing ambulatory electrocardiogram monitoring to reduce conduction related death after transcatheter aortic valve replacement

OBJECTIVE

The purpose of this study is to assess the utility of ambulatory cardiac monitoring (ACM) in detecting delayed advanced conduction abnormalities (DACA) and associated 30-day mortality.

BACKGROUND

DACA are well-known complications of TAVR and may be associated with post-discharge mortality within 30-days.

METHODS

Between October 2019 and October 2020, TAVR patients who were discharged home without a permanent pacemaker (PPM) were monitored with an ACM device for 14-days. The incidence of DACA at follow up, mortality and readmission within 30-days were investigated. The risk of DACA was assessed in three patient categories based on a composite of their 12-lead electrocardiogram (ECG) data. Group I: Normal pre-TAVR, periprocedural, and discharge ECGs. Group II: Normal pre-TAVR and abnormal subsequent ECGs. Group III. Abnormal baseline and abnormal subsequent ECGs.

RESULTS

Among 340 TAVR patients, 248 were discharged home with an ACM device. The overall incidence of DACA was 7% (n = 17), of whom 4% (n = 10) required a PPM. Mortality and readmission between discharge and 30 days was 0% and 8.3%, respectively. Stratification of patients identified 96 (38.7%) patients in Group I: 50 (20%) in Group II, and 102 (41%) in Group III. The incidence of DACA requiring a PPM was 0% in Group I, 4% (n = 2) in Group II, and 8.5% (n = 8) in Group III (p < 0.004).

CONCLUSIONS

In TAVR patients who were discharged home with ACM, none died between discharge and 30-days. For those with normal baseline, perioperative and discharge ECG, there were no events of DACA at 14-days.

Transcatheter Aortic Valve Implantation: The Evolving Role of the Radiologist in 2021

BACKGROUND

 Transcatheter aortic valve implantation (TAVI) has gained worldwide acceptance and implementation as an alternative therapeutic option in patients with severe aortic valve stenosis unable to safely undergo surgical aortic valve replacement. This transformative technique places the radiologist in a key position in the pre-procedural assessment of potential candidates for this technique, delivering key anatomical information necessary for patient eligibility and procedural safety. Recent trials also provide encouraging results to potentially extend the indication to patients with safer risk profiles.

METHOD

 The review is based on a PubMed literature search using the search terms "transcatheter heart valve", "TAVI", "TAVR", "CT", "imaging", "MR" over a period from 2010-2020, combined with personal comments based on the author's experience.

RESULTS AND CONCLUSION

 CT plays a prominent role in the pre-procedural workup, delivering as a true 3D imaging modality optimal visualization of the complex anatomy of the aortic root with simultaneous evaluation of the patency of the different access routes. As such, the contribution of CT is key for the determination of patient eligibility and procedural safety. This input is supplementary to the contributions of other imaging modalities and forms an important element in the discussions of the Heart Valve Team. Knowledge of the procedure and its characteristics is necessary in order to provide a comprehensive and complete report. While the role of CT in the pre-procedural evaluation is well established, the contribution of CT and MR and the clinical significance of their findings in the routine follow-up after the intervention are less clear and currently the subject of intense investigation. Important issues remain, including the occurrence and significance of subclinical leaflet thrombosis, prosthetic heart valve endocarditis, and long-term structural valve degeneration.

KEY POINTS

  · CT plays a crucial role in evaluating transcatheter heart valve candidates. · Evaluation must include the dimensions of the aortic root and access paths. · The exact post-procedural role of CT and MRI has not yet been determined..

CITATION FORMAT

· Salgado R, El Addouli H, Budde RP. Transcatheter Aortic Valve Implantation: The Evolving Role of the Radiologist in 2021. Fortschr Röntgenstr 2021; 193: 1411 - 1425.

Transcatheter Versus Surgical Aortic Valve Replacement in Patients With Complex Coronary Artery Disease

OBJECTIVES

The aim of this study was to compare, in a cohort of patients with complex coronary artery disease (CAD) and severe aortic stenosis (AS), the clinical outcomes associated with transfemoral transcatheter aortic valve replacement (TAVR) (plus percutaneous coronary intervention [PCI]) versus surgical aortic valve replacement (SAVR) (plus coronary artery bypass grafting [CABG]).

BACKGROUND

Patients with complex CAD were excluded from the main randomized trials comparing TAVR with SAVR, and no data exist comparing TAVR + PCI vs SAVR + CABG in such patients.

METHODS

A multicenter study was conducted including consecutive patients with severe AS and complex CAD (SYNTAX [Synergy Between PCI with Taxus and Cardiac Surgery] score >22 or unprotected left main disease). A 1:1 propensity-matched analysis was performed to account for unbalanced covariates. The rates of major adverse cardiac and cerebrovascular events (MACCE), including all-cause mortality, nonprocedural myocardial infarction, need for new coronary revascularization, and stroke, were evaluated.

RESULTS

A total of 800 patients (598 undergoing SAVR + CABG and 202 undergoing transfemoral TAVR + PCI) were included, and after propensity matching, a total of 156 pairs of patients were generated. After a median follow-up period of 3 years (interquartile range: 1-6 years), there were no significant differences between groups for MACCE (HR for transfemoral TAVR vs SAVR: 1.33; 95% CI: 0.89-1.98), all-cause mortality (HR: 1.25; 95% CI: 0.81-1.94), myocardial infarction (HR: 1.16; 95% CI: 0.41-3.27), and stroke (HR: 0.42; 95% CI: 0.13-1.32), but there was a higher rate of new coronary revascularization in the TAVR + PCI group (HR: 5.38; 95% CI: 1.73-16.7).

CONCLUSIONS

In patients with severe AS and complex CAD, TAVR + PCI and SAVR + CABG were associated with similar rates of MACCE after a median follow-up period of 3 years, but TAVR + PCI recipients exhibited a higher risk for repeat coronary revascularization. Future trials are warranted.

Comparing Single- and Dual Antiplatelet Therapies Following Transcatheter Aortic Valve Implantation

BACKGROUND

Transcatheter aortic valve implantation has been an established treatment in patients with symptomatic severe aortic stenosis. However, the postoperative antiplatelet regimen after transcatheter aortic valve implantation was not established certainly. The aim of this meta-analysis is to compare the safety and efficacy of single- (SAPT) and dual-antiplatelet therapies (DAPT) in patients undergoing transcatheter aortic valve implantation.

METHODS

Eligible randomized controlled trials and cohort studies published before February 2021 were retrieved from PubMed, Embase, and the Cochrane Library. We calculated odds ratios with 95% confidence intervals.

RESULTS

Nine articles, involving 19,277 patients, met the selection criteria. In the short-term outcome, compared with SAPT, DAPT was associated with a significantly higher rate of bleeding (odds ratios, 95% confidence intervals: 3.00, 1.67-5.38) and showed no significant differences in thrombotic events (odds ratios, 95% confidence intervals: 1.25, 0.74-2.11) and all-cause mortality (odds ratios, 95% confidence intervals: 0.84; 0.42-1.69). In the long-term outcome, DAPT was associated with a significantly higher bleeding rate (odds ratios, 95% confidence intervals: 1.85, 1.24-2.78) and showed no differences in thrombotic events (odds ratios, 95% confidence intervals: 1.13, 0.86-1.48) and all-cause mortality (odds ratios, 95% confidence intervals: 1.12, 0.95-1.32). Our trial sequential analysis confirmed DAPT didn't confer any benefit for reducing all-cause mortality and thrombotic events, and carried a higher risk of bleeding than SAPT.

CONCLUSIONS

SAPT should be a sufficient antiplatelet strategy in post- transcatheter aortic valve implantation patients without indications for oral anticoagulation medication, especially in the long-term follow-up period.

The JenaValve pericardial transcatheter aortic valve replacement system to treat aortic valve disease

Transcatheter aortic valve replacement is a valuable alternative technique to surgery and the spectrum of therapy continues to evolve. The JenaValve Pericaridal transcatheter aortic valve replacement System allows prosthesis fixation in a native, noncalcified aortic annulus with a unique paper clip-like anchorage mechanism. The low rate of paravalvular leakage and permanent pacemaker implantation emphasizes the further widespread use of the JenaValve - despite the limited data available. In May 2021, a CE mark for the transfemoral implantation in both aortic regurgitation and aortic stenosis was granted. However, no data have been published so far. The ongoing ALIGN trials are expected to provide the pending long-term data.

Bedside Electrophysiological Study Using a Temporary Pacemaker May Predict Recurrence of Atrioventricular Block After Transcatheter Aortic Valve Replacement

High-degree atrioventricular block (HAVB) or complete heart block (CHB) is a common complication associated with transcatheter aortic valve replacement (TAVR). However, some patients with HAVB/CHB recover with time. The results of electrophysiological studies (EPSs) using permanent pacemaker implantation (PPI) in patients with suspicious HAVB/CHB are considered controversial.This study aimed to evaluate whether HAVB/CHB induction at the bedside using a temporary pacemaker can predict recurrence in patients who had recovered from HAVB/CHB after TAVR.We enrolled a total of 11 patients who had recovered from HAVB/CHB and evaluated their electrophysiology using right ventricular pacing and/or procainamide administration.HAVB/CHB induction was positive. Three patients tested positive for HAVB/CHB, whereas 8 tested negative. The ejection fraction and the interval between HAVB/CHB onset and EPS were found to be significant. HAVB/CHB positive patients underwent PPI. A patient with a balloon-expandable valve tested positive just before recovery of CHB, but tested negative 5 days later and was included in the negative group. The 4 patients who tested negative received a cardiovascular implantable electric device (CIED). We observed HAVB/CHB in 2 patients who had previously tested positive after 3 months. Among those who tested negative, those with CIED had no HAVB/CHB, and others showed neither HAVB/CHB on electrocardiogram nor experienced syncope or sudden death.Our EPS revealed that HAVB/CHB induction may predict HAVB/CHB recurrence after TAVR. Valve type and EPS timing may affect the results.

Device profile of the SAPIEN 3 transcatheter heart valve in low-risk patients with aortic stenosis: overview of its safety and efficacy

INTRODUCTION

Transcatheter aortic valve replacement (TAVR) has become a treatment of reference for patients with symptomatic severe aortic stenosis, and the balloon-expandable SAPIEN 3 and SAPIEN 3 Ultra transcatheter heart valve systems are two of the most broadly used worldwide. Lately, TAVR has progressively expanded toward the treatment of low-risk patients.

AREAS COVERED

In this review we aimed to describe the main characteristics of the SAPIEN 3 valve, and to delineate the main clinical findings regarding the safety and efficacy associated with this THV system in low-risk patients undergoing TAVR.

EXPERT OPINION

The approval of THV systems for use in low-risk patients has been a significant step forward in expanding current TAVR indications. Along with procedural refinement and growing operator experience, device iterations implemented in new-generation THV systems have played a vital role in the successful spread of TAVR. The availability of SAPIEN 3 represented an inflection point, as it allows for a predictable positioning and safer navigability while dramatically decreasing the rate of residual paravalvular leakage compared to previous balloon-expandable systems. However, some unresolved issues remain like the relatively high rates of conduction disturbances and the uncertainty about valve performance in the long-term. Future studies are warranted.

Aortic Valve Replacement in Low-Risk Patients With Severe Aortic Stenosis Outside Randomized Trials

BACKGROUND

Recent randomized trials including low-risk patients showed positive results for transcatheter aortic valve replacement (TAVR) compared to surgical aortic valve replacement (SAVR), but patients with non-tricuspid aortic valve (NTAV), severe coronary artery disease (SevCAD), and those requiring concomitant mitral/tricuspid valve (CMTV) or concomitant ascending aorta replacement (CAAR) interventions were excluded.

OBJECTIVES

This study sought to evaluate the presence and impact of the main clinical variables not evaluated in TAVR versus SAVR trials (NTAV, SevCAD, and CMTV or CAAR intervention) in a large series of consecutive low-risk patients with severe aortic stenosis (SAS) undergoing SAVR.

METHODS

Single-center study including consecutive patients with SAS and low surgical risk (Society of Thoracic Surgeons score of <4%) undergoing SAVR. Baseline, procedural characteristics, and 30-day outcomes were prospectively collected.

RESULTS

Of 6,772 patients with SAS who underwent SAVR between 2000 and 2019, 5,310 (78.4%) exhibited a low surgical risk (mean Society of Thoracic Surgeons score: 1.94 ± 0.87%). Of these, 2,165 patients (40.8%) had at least 1 of the following: NTAV (n = 1,468, 27.6%), SevCAD (n = 307, 5.8%), CMTV (n = 306, 5.8%), and CAAR (n = 560, 10.5%). The 30-day mortality and stroke rates for the overall low-risk SAS cohort were 1.9% and 2.4%, respectively. The mortality rate was similar in the SevCAD (2.6%) and CAAR (2.1%) groups versus the rest of the cohort (odds ratio [OR]: 1.79; 95% confidence interval [CI]: 0.85 to 3.75, and OR: 1.64; 95% CI: 0.88 to 3.05, respectively), lower in the NTAV group (0.9%; OR: 0.42; 95% CI: 0.22 to 0.81), and higher in the CMTV group (5.9%; OR: 2.61; 95% CI: 1.51 to 4.5).

CONCLUSIONS

In a real-world setting, close to one-half of the low-risk patients with SAS undergoing SAVR exhibited at least 1 major criterion not evaluated in TAVR versus SAVR randomized trials. Clinical outcomes were better than or similar to those predicted by surgical scores in all groups but those patients requiring CMTV intervention. These results may help determine the impact of implementing the results of TAVR-SAVR trials in real practice and may inform future trials in specific groups.

Heart failure following transcatheter aortic valve replacement

Introduction: Over the past decade, the number of transcatheter aortic valve replacement (TAVR) procedures has increased exponentially. Despite major improvements in both device and successes, the rate of hospital readmission after TAVR remains high, with heart failure (HF) decompensation being one of the most important causes.Areas covered: This review provides an overview of the current status of HF following TAVR, including details about its incidence, clinical impact, contributing factors, and current and future treatment perspectives.Expert opinion: HF decompensation has been identified as the most common cause of rehospitalization following TAVR, and it has been associated with a negative prognosis. Multiple preexisting factors including low flow status, cardiac amyloidosis, myocardial fibrosis, multivalvular disease, pulmonary hypertension, coronary artery disease, and atrial fibrillation have been associated with an increased risk of HF events. Also, multiple post-procedural factors like the occurrence of significant paravalvular leaks, severe prosthesis-patient mismatch, and conduction disturbances have also contributed to increase this risk . Thus, reducing HF events in TAVR recipients would require a multifactorial and multidisciplinary effort including the optimization of the medical treatment and close follow-up and treatment of residual or concomitant valvular disease and conduction disturbance issues. Future studies in this challenging group of patients are warranted.

The current diagnosis and treatment of patients with aortic valve stenosis

Aortic valve stenosis (AS) is the third most frequent cardiovascular abnormality after coronary artery disease and hypertension. A bicuspid aortic valve is the most common cause for AS until seventh decade and calcific valve degeneration is responsible thereafter. In symptomatic patients, The risk of death increases from ≤1%/year to 2%/month. An echo valve area ≤1 cm², peak transaortic velocity ≥4 m/s, mean valve gradient ≥40 mmHg and/or computerized tomography valve calcium score >2000 Agatston units (AU) for males or more than 1200 AU for females indicate severe AS. AS stages and management are discussed. Valve replacement is based on surgical risk, valve durability/hemodynamics, need for anticoagulation and patient preferences. EuroSCORE ≥20%, Society of Thoracic Surgeons Predicted Risk of Mortality ≥8% and co-morbidities indicate high surgical risk. Surgery is recommended for low-intermediate risk patients. Transcatheter aortic valve implantation is an alternative in older patients at low, intermediate, high or prohibitive risk. Transaortic valve implantation/replacement trials are summarized.

Meta-analysis Comparing Early Outcomes Following Transcatheter Aortic Valve Implantation With the Evolut Versus Sapien 3 Valves

We aimed to compare the early (in-hospital/30-day) outcomes (major periprocedural complications, device success/valve performance, and mortality) following transcatheter aortic valve implantation with the Sapien 3 versus Evolut transcatheter valve systems. This was a systematic review from PubMed and EMBASE databases for studies reporting raw data or estimates. The outcomes analyzed were (1) in-hospital/30-day major periprocedural complications, (2) device success and valve performance, and (3) mortality. The outcomes were defined according to VARC-2 criteria. A total of 24,628 transcatheter aortic valve implantation patients from 9 studies (1 randomized, 8 observational [5 case- or propensity-matched analyses]) were included: 12,411 and 12,217 patients had Sapien 3 and Evolut valve implantation, respectively. There were no differences between devices regarding in-hospital/30-day stroke (risk ratio [RR] 0.95, 95% confidence interval [CI] 0.34 to 2.66), major vascular complications (RR 1.03, 95% CI 0.63 to 1.68), acute kidney injury (RR 1.17, 95% CI 0.78 to 1.77), device success (RR 1.00, 95% CI 0.97 to 1.04) and moderate-severe residual aortic regurgitation (RR 0.49, 95% CI 0.20 to 1.17). Sapien 3 recipients exhibited lower risk of permanent pacemaker implantation (RR 0.66, 95% CI 0.55 to 0.80), a higher risk of life-threatening bleeding (RR 1.82, 95% CI 1.18 to 2.80), and higher residual transvalvular gradients (mean difference 3.95 mmHg, 95% CI 3.37 to 4.56). A lower risk of in-hospital/30-day mortality was observed for Sapien 3 (RR 0.79, 95% CI 0.69 to 0.90). In conclusion, the similarities in device success rate and major periprocedural complications (except for a higher and lower risk of permanent pacemaker implantation and life-threatening bleeding, respectively, with the Evolut system) support the lack of a valve type effect accounting for the increased mortality risk observed with the Evolut valve.

Evaluation of Acquired Thrombocytopenia According to the Balloon-Expandable Versus Self-Expandable Valves in Patients Undergoing Transcatheter Aortic Valve Replacement

In patients with severe aortic stenosis, the data about the incidence of acquired thrombocytopenia according to the use of balloon-expandable or self-expandable valves are limited. We investigated the relationship between the post-transcatheter aortic valve replacement (TAVR) thrombocytopenia and the balloon-expandable or self-expandable valves. A total of 127 consecutive patients who underwent TAVR were retrospectively analyzed. Among the study population, 61 (48%) patients underwent TAVR with the balloon-expandable valve and the 66 (52%) patients with the self-expandable valve. Procedural success did not differ between the groups (P = .575). The access site complications and in-hospital mortality were the same across the groups (P = .225 and P = .466). However, paravalvular (PV) leaks were significantly higher in the self-expandable valve group (P = .007). Among all, 65 patients experienced thrombocytopenia, which was more frequent in the self-expandable valve group (63.6 vs 37.7%, P = .005). In multivariate analyses, admission platelet count, PV leak, and self-expandable valve deployment were the predictors of thrombocytopenia (P = .001, P = .002, and P = .021, respectively). The present study showed a higher incidence of acquired thrombocytopenia in the self-expandable valve group. Although the procedural success was similar between the groups, postprocedural PV leaks were more common in the self-expandable valve group.

Early Valve Replacement for Severe Aortic Valve Disease: Effect on Mortality and Clinical Ramifications

Timing of aortic valve intervention for chronic aortic regurgitation (AR) and/or aortic stenosis (AS) potentially affects long-term survival. The 2014 American Heart Association/American College of Cardiology (AHA/ACC) guidelines provide recommendations for the timing of intervention. Subsequent to the guidelines' release, several studies have been published that suggest a survival benefit from earlier timing of surgery for severe AR and/or AS. The aim of this review was to determine whether patients who have chronic aortic regurgitation (AR) and/or aortic stenosis (AS) have a survival benefit from earlier timing of aortic valve surgery. Medical databases were systematically searched from January 2015 to April 2020 for randomized controlled trials (RCTs) and observational studies that examined the timing of aortic valve replacement surgery for chronic AR and/or AS. For chronic AR, four observational studies and no RCTs were identified. For chronic AS, five observational studies, one RCT and one meta-analysis were identified. One observational study examining mixed aortic valve disease (MAVD) was identified. All of these studies, for AR, AS, and MAVD, found long-term survival benefit from timing of aortic valve surgery earlier than the current guidelines. Larger prospective RCTs are required to evaluate the benefit of earlier surgical intervention.

Transapical transcatheter aortic valve implantation for predominant aortic regurgitation with a self-expandable valve

Background

Transcatheter aortic valve implantation (TAVI) has become the gold standard for high-risk severe aortic stenosis. However, the experience of treating aortic regurgitation (AR) with this technology is still limited. Previously, we have demonstrated excellent 1-year outcomes of transapical TAVI with J-Valve^TM (JieCheng Medical Technology Co., Ltd., Suzhou, China) in treating predominant AR, while the mid-term outcomes up to 4 years have never been reported.

Methods

Transapical TAVI with J-Valve^TM to treat predominant AR was performed in 47 patients in Zhongshan Hospital from May 2014 through October 2018. Procedural and clinical outcomes with follow-up up to 4 years were analyzed using Valve Academic Research Consortium-2 criteria (VARC-2).

Results

All patients (age 73.7±7.9 years) were considered to be prohibitive or high-risk for surgical aortic valve replacement (SAVR) (logistic European System for Cardiac Operative Risk Evaluation, 21.1% to 44.4%; mean, 24.3%±5.1%) after evaluated by a multidisciplinary heart team. Transapical implantations were successful in all patients. The clinical outcomes of the entire cohort in the latest follow-up (371 to 1,968 days, median 574 days) included all-cause mortality (6.4%), disabling stroke (2.3%), new permanent pacemaker (6.8%) and valve-related re-intervention (0). Paravalvular leak (PVL) was rate as none or trace in 37 of 44 and mild in 7 of 44 patients at the latest follow-up. Mean transvalvular gradient was favorable after valve implantation during follow-up at 9.3±2.5 mmHg.

Conclusions

This study revealed that, transapical TAVI with J-Valve^TM for treating AR has encouraging mid-term outcomes, and the advantages at one year demonstrated in previous study can be maintained through 4 years.

Valve Hemodynamics Following Transcatheter or Surgical Aortic Valve Replacement in Patients With Small Aortic Annulus

This study aimed to compare the hemodynamic performance of transcatheter and surgical aortic valves in patients with severe symptomatic aortic stenosis and small aortic annulus (SAA) and to determine the valve hemodynamics according to transcatheter valve type. Consecutive surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) patients with SAA were case-matched (1:1) on the basis of sex, body surface area, aortic annulus diameter, and left ventricular ejection fraction. A total of 357 patients in each group constituted the final study population. A second match on the basis of aortic annulus diameter and valve/annulus calcium burden was performed within the TAVR group to compare the valve performance between balloon- (n = 52) and self-expanding (n = 52) transcatheter valve systems (BEV, SEV). The echocardiograms performed at hospital discharge were used for evaluating valve hemodynamics. The mean annulus diameter of the study population was 19.2 ± 0.3 mm. The TAVR group (vs SAVR) exhibited lower mean gradient (12 ± 7 mm Hg vs 15 ± 6 mm Hg, p <0.001), larger effective orifice area (1.46 ± 0.39 cm² vs 1.25 ± 0.37 cm², p <0.001) and a lower rate of severe prosthesis-patient mismatch (PPM) (14% vs 24%, p = 0.001). Moderate-severe AR was present in 2.5% of the TAVR recipients versus none patient in the SAVR group. There were no differences in valve hemodynamics between balloon-expanding transcatheter valve system and self-expanding transcatheter valve system, and similar rates of severe PPM were observed in both groups (p = 0.488). In conclusion, TAVR presented superior valve hemodynamics and lower incidence of severe PPM compared with SAVR in SAA patients. Similar valve performance results were observed between transcatheter valve types.

Late Electrocardiographic Changes in Patients With New-Onset Left Bundle Branch Block Following Transcatheter Aortic Valve Implantation

This study sought to determine, in patients with new-onset persistent left bundle branch block (NOP-LBBB) after transcatheter aortic valve implantation (TAVI), the incidence and factors associated with (i) LBBB recovery and (ii) permanent pacemaker implantation (PPI) at 1-year follow-up. This was a multicenter study including 153 patients (mean age: 81 ± 5 years, 56% of women) with NOP-LBBB post-TAVI (balloon-expandable valve in 112 patients). Delta PR (ΔPR) and delta QRS (ΔQRS) were defined as the difference in PR and QRS length between baseline and hospital discharge ECG, and the relative ΔPR and ΔQRS as absolute ΔPR and ΔQRS divided by baseline PR and QRS length, respectively. The patients had a clinical visit and 12-lead ECG at 1-year follow-up. LBBB recovery was observed in 50 patients (33%), and 14 patients (9%) had advanced conduction disturbances requiring PPI during the follow-up period. No clinical or ECG variables were associated with LBBB recovery, including prosthesis type (self- or balloon-expandable valve, p = 0.563), QRS width at baseline/discharge or absolute/relative ΔQRS (p >0.10 for all). The presence of atrial fibrillation at baseline (0.026), a longer PR interval at discharge (0.009), and a longer absolute and relative ΔPR (p = 0.002 and p = 0.004, respectively) were associated with an increased risk of PPI at 1-year follow-up. In conclusion, NOP-LBBB post-TAVI resolved in one-third of patients at 1-year follow-up, but no clinical or ECG variables were associated with LBBB recovery. Conversely, a nonsinus rhythm at baseline and a longer ΔPR were associated with an increased risk of PPI within the year after TAVI.

Antithrombotic Therapy After Transcatheter Aortic Valve Replacement

The performance of transcatheter aortic valve replacement has expanded considerably during the past decade. Technological advances and refinement in implantation techniques have resulted in improved procedural outcomes, whereas indications are progressively extending toward lower-risk patients. Ischemic/embolic complications and major bleeding remain important and strongly correlate to mortality. In this regard, the optimal antithrombotic regimen after successful transcatheter aortic valve replacement remains unclear, in the absence of randomized trials. For patients without an indication for oral anticoagulation, empirical treatment with dual antiplatelet therapy (aspirin plus clopidogrel) for 3 to 6 months is currently recommended. However, dual antiplatelet therapy has been preliminarily associated with increased risk of bleeding compared with single antiplatelet therapy without significant ischemic benefit. Non-vitamin K oral anticoagulants and warfarin have also entered clinical investigation, to address the issue of preexisting or new-onset of atrial fibrillation and potentially attenuate subclinical leaflet thrombosis. Clinical trials are necessary to systematically address the risks and benefits of these approaches. In this review, we present the pathophysiological mechanisms of post-transcatheter aortic valve replacement complications and provide updated insights on the rationale behind the various antithrombotic regimens being currently evaluated in large randomized trials.

Blood Disorders in Patients Undergoing Transcatheter Aortic Valve Replacement: A Review

Transcatheter aortic valve replacement (TAVR) is well established for treating patients with severe aortic stenosis considered at intermediate to high surgical risk. Blood disorders such as anemia, thrombocytopenia, and acquired type 2A von Willebrand disease are relatively frequent in TAVR candidates, and multiple studies to date have highlighted their potential clinical association with mortality and/or bleeding complications post-TAVR. The present review provides an overview of various blood disorders observed pre- and post-TAVR, with special focus on their incidence, etiology, clinical association, and management.

Incidence, Clinical Characteristics, and Impact of Acute Coronary Syndrome Following Transcatheter Aortic Valve Replacement

OBJECTIVES

The authors sought to assess the incidence, predictors, management, and prognosis of acute coronary syndrome (ACS) following TAVR.

BACKGROUND

About one-half of the patients undergoing transcatheter aortic valve replacement (TAVR) have concurrent coronary artery disease (CAD). However, the occurrence and clinical impact of coronary events following TAVR remain largely unknown.

METHODS

Consecutive patients undergoing TAVR in our institution between May 2007 and November 2017 were included. Patients were followed at 1, 6, and 12 months, and yearly thereafter. ACS was diagnosed and classified according to the Third Universal Definition of Myocardial Infarction.

RESULTS

A total of 779 patients (mean age 79 ± 9 years, 52% male, mean STS: 6.8 ± 5.1%) were included, 68% of which had a history of CAD. At a median follow-up of 25 (interquartile range: 10 to 44) months, 78 patients (10%) presented at least 1 episode of ACS, with one-half of the events occurring within the year following TAVR. Clinical presentation was type 2 non-ST-segment elevation myocardial infarction (35.9%), unstable angina (34.6%), type 1 non-ST-segment elevation myocardial infarction (28.2%), and ST-segment elevation myocardial infarction (1.3%). Male sex (hazard ratio [HR]: 2.19; 95% confidence interval [CI]: 1.36 to 3.54; p = 0.001), prior CAD (HR: 2.78; 95% CI: 1.50 to 5.18; p = 0.001), and nontransfemoral approach (HR: 1.71; 95% CI: 1.04 to 2.75; p = 0.035) were independently associated with ACS. Coronary angiography was performed in 53 (67.9%) patients with ACS, and 30 of them (56.6%) underwent percutaneous coronary intervention. In-hospital death rate at the time of the ACS episode was 3.8%. At a median follow-up of 21 (interquartile range: 8 to 34) months post-ACS, all-cause and cardiovascular death rates were 37.3% and 25.3%, respectively.

CONCLUSIONS

Approximately one-tenth of patients undergoing TAVR were readmitted for an ACS after a median follow-up of 25 months. Male sex, prior CAD, and nontransfemoral approach were independent predictors of ACS. ACS was associated with high midterm mortality.

Transcatheter aortic valve replacement: clinical safety and performance data

Introduction: Patients with severe aortic stenosis and regurgitation who are inoperable or at high-risk for surgery can be treated with transcatheter aortic valve replacement (TAVR). The aim of this study was to provide a comprehensive overview of the literature of TAVR and reported clinical and performance outcomes. Areas covered: A total of 16 devices, described in 204 articles describing clinical and performance outcomes, were included. The most frequently observed outcome was 30-day mortality, ranging between 0-23%. Other commonly reported clinical outcomes were 30-day stroke, ranging between 0-14.3% and pacemaker implantation, ranging from 0-44.9%. The most common valve performance outcome was aortic valve regurgitation, however, mostly reported at 7 days follow-up. Next to a follow-up period of 30 days, numerous articles reported outcomes at 6 months and 1 year. The numbers of articles describing outcomes with a longer follow-up as well as including intermediate and low-risk patients were limited. Expert commentary: This literature review provided a clear overview of the reported clinical and performance outcomes of TAVR devices. Despite the frequently used VARC-2 definitions, we identified a huge variation across studies. Future studies using standardized definitions of study set-ups and outcomes are essential and might lead to better insights of TAVR.

Long-Term Outcomes After Transcatheter Aortic Valve-in-Valve Replacement

BACKGROUND

Data on long-term outcomes after valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) are scarce. The objective of this study was to determine the long-term clinical outcomes and structural valve degeneration (SVD) over time in patients undergoing ViV-TAVR.

METHODS AND RESULTS

Consecutive patients undergoing ViV-TAVR in 9 centers between 2009 and 2015 were included. Patients were followed yearly, and clinical and echocardiography data were collected prospectively. SVD was defined as subclinical (increase >10 mm Hg in mean transvalvular gradient+decrease >0.3 cm² in valve area or new-onset mild or moderate aortic regurgitation) and clinically relevant (increase >20 mm Hg in mean transvalvular gradient+decrease >0.6 cm² in valve area or new-onset moderate-to-severe aortic regurgitation). A total of 116 patients (mean age, 76±11 years; 64.7% male; mean Society of Thoracic Surgeons score, 8.0±5.1%) were included. Balloon- and self-expandable valves were used in 47.9% and 52.1% of patients, respectively, and 30-day mortality was 6.9%. At a median follow-up of 3 years (range, 2-7 years), 30 patients (25.9%) had died, 20 of them (17.2%) from cardiovascular causes. Average mean transvalvular gradients remained stable up to 5-year follow-up ( P=0.92), but clinically relevant SVD occurred in 3/99 patients (3.0%), and 15/99 patients (15.1%) had subclinical SVD. One patient with SVD had redo ViV-TAVR.

CONCLUSIONS

About one-fourth of ViV-TAVR recipients had died after a median follow-up of 3 years. Overall valve hemodynamics remained stable over time and clinically relevant SVD was infrequent, but 1 out of 10 patients exhibited some degree of SVD.

Clinical and Technical Characteristics of Coronary Angiography and Percutaneous Coronary Interventions Performed before and after Transcatheter Aortic Valve Replacement with a Balloon-Expandable Valve

Objectives

To report on the feasibility and technical differences between coronary procedures performed before and after TAVR with the balloon-expandable Edwards-SAPIEN or the SAPIEN XT valves.

Background

Coronary artery disease (CAD) and aortic stenosis often coexist. Transcatheter aortic valve replacement (TAVR) is emerging as a treatment for younger and lower surgical risk patients who might not present with clinically evident CAD before TAVR. The demand for performing post-TAVR coronary angiograms (CAs) and percutaneous coronary interventions (PCIs) will thus increase, posing new technical challenges.

Methods

Over 1000 TAVRs were performed at the Quebec Heart and Lung Institute, of which 616 with the abovementioned valves. Of these, 28 patients had an analyzable pre- and post-TAVR CAs and 13 patients had pre- and post-TAVR PCIs performed. Procedural characteristics were gathered from all coronary procedures and subsequently compared amongst the same type of procedure performed at these two distinct time periods.

Results

Neither CAs‐nor PCIs‐performed after valve implantation revealed significant differences regarding arterial access site, catheter diameter, number of diagnostic or guiding catheters used, procedural duration, fluoroscopy time, or achievement of selective coronary injection. Lesion location and classification, as well as the preference of using a drug-eluting stent, remained unchanged. During post-TAVR CA, the amount of contrast delivered and the radiation dose area product were significantly lower compared with pre-TAVR CA values.

Conclusions

Performance of CA and PCI after TAVR with a balloon-expandable valve appears unaffected by its presence.

Transcatheter Aortic Valve Replacement With the HLT Meridian Valve

Background:

While most self-expanding transcatheter valves are repositionable, only one fully retrievable valve is currently available. The Meridian valve is a new self-expanding valve with full retrievability properties. The objective of our study was to evaluate the early feasibility, preliminary safety, and efficacy of transcatheter aortic valve replacement with the HLT Meridian valve (HLT, Inc).

Methods:

This was a multicenter early feasibility study including patients with severe aortic stenosis at high surgical risk undergoing transfemoral transcatheter aortic valve replacement with the 25-mm Meridian valve. All serious adverse events were adjudicated by an independent clinical events committee according to Valve Academic Research Consortium-2 criteria. Echocardiography data were assessed by an independent echocardiography core laboratory.

Results:

A total of 25 patients (mean age, 85±6 years; 80% of men) were included. The valve was successfully implanted in 22 (88%) patients (annulus too large and extreme horizontal aorta in 2 and 1 unsuccessful cases, respectively). Valve retrieval because of an initial nonadequate positioning was attempted and successfully performed in 10 (40%) patients. Echocardiography post-transcatheter aortic valve replacement showed a low mean residual gradient (10±4 mm Hg) and the absence of moderate-severe aortic regurgitation (none-trace and mild aortic regurgitation in 76% and 24% of patients, respectively). Mortality at 30 days was 8%, with no cases of disabling stroke, valve embolization, or major/life-threatening bleeding complications. At 6-month follow-up, the cumulative mortality rate was 12%, with no changes in echocardiographic parameters and no cases of valve dysfunction. The majority of patients (89%) were in New York Heart Association class I-II at 6 months.

Conclusions:

Transcatheter aortic valve replacement with the Meridian valve was feasible and associated with acceptable early and 6-month clinical results. Valve retrieval after full valve deployment was successfully performed in all attempted cases, and valve performance was excellent, with low residual gradients, no cases of moderate-severe aortic regurgitation, and none-trace residual aortic regurgitation in the majority of patients.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT02838680 (RADIANT-Canada); NCT02799823 (RADIANT-US).

Effect of Aortic Regurgitation by Cardiovascular Magnetic Resonance After Transcatheter Aortic Valve Implantation

Cardiovascular magnetic resonance (CMR) has demonstrated a high accuracy for evaluating the severity of aortic regurgitation (AR). However, scarce data exist on the impact of AR as evaluated by CMR on clinical outcomes following transcatheter aortic valve implantation (TAVI). The objective of this study was to evaluate the impact of AR as determined by CMR on clinical outcomes (mortality, heart failure [HF] hospitalization) post-TAVI. A total of 448 TAVI recipients from 2 centers (mean age: 80 ± 7 years, mean STS: 5.8 ± 5.4%) who survived the periprocedural period with no pacemaker implantation were included. A newer generation transcatheter valve system was used in 213 patients (48%). The CMR examination was performed at a median of 12 (IQR: 7 to 21) days post-TAVI. After a mean follow-up of 24 ± 19 months, a total of 94 patients (21%) had died and 72 patients (16%) had at least 1 hospitalization because of decompensated HF. The aortic regurgitation fraction (RF) as determined by CMR was an independent predictor of mortality (hazard ratio[HR]:1.06 for each increase of 10%, 95% confidence interval [CI]: 1.01 to 1.12, p = 0.03) and HF hospitalization (HR:1.15 for each increase of 10%, 95% CI:1.02 to 1.30, p = 0.02). The rate of moderate-severe CMR-AR defined as a RF ≥30% was 3%, and this was associated with an increased risk of mortality (HR: 2.63, 95% CI: 2.30 to 2.99, p <0.001) and HF hospitalization (HR: 2.96, 95% CI: 1.62 to 5.42, p ˂0.001). A stepwise increase in the risk of mortality and HF hospitalization was observed with an increase in AR severity, with a peak increase among patients with RF ≥30%. In conclusion, our results showed the clinical usefulness of evaluating AR severity by CMR post-TAVI. CMR would be particularly helpful in doubtful cases or those with discordances between echocardiography and clinical data.

Transcatheter aortic valve implantation: a new standard of care

Aortic stenosis is the most common valvular lesion requiring intervention and with an ageing population, its burden is likely to increase. Increasing comorbidity and a desire for less invasive treatment strategies has facilitated the expansion of percutaneous aortic valve therapies. Robust clinical trial data are now available to support the role of transcatheter aortic valve implantation (TAVI) in patients of prohibitive, high and now intermediate surgical risk. The introduction of a Medicare Benefits Schedule reimbursement is likely to see TAVI use grow exponentially in Australia over the next 5 years. Clinical trials evaluating low risk patients may be the final frontier to see TAVI become the standard of care for most patients with severe aortic stenosis.

TAVI for Pure Native Aortic Regurgitation: Are We There Yet?

Treatment of degenerative aortic stenosis has been transformed by transcatheter aortic valve implantation (TAVI) over the past 10-15 years. The success of various technologies has led operators to attempt to broaden the indications, and many patients with native valve aortic regurgitation have been treated 'off label' with similar techniques. However, the alterations in the structure of the valve complex in pure native aortic regurgitation are distinct to those in degenerative aortic stenosis, and there are unique challenges to be overcome by percutaneous valves. Nevertheless some promise has been shown with both non-dedicated and dedicated devices. In this article, the authors explore some of these challenges and review the current evidence base for TAVI for aortic regurgitation.