TAVI: Simplification Is the Ultimate Sophistication

Cardiology department versus intensive care unit admission after successful uncomplicated transcatheter aortic valve replacement (TAVR)

BACKGROUND

Most patients after transcatheter aortic valve replacement (TAVR) are admitted directly to the cardiac intensive care unit (CICU) despite low complication rates. Reducing unnecessary CICU hospitalization reduces healthcare costs. This study aimed to compare the outcomes between patients admitted directly to the cardiology department (CD) and those admitted to CICU based on prespecified protocols.

METHODS

Historical cohort study of all patients who underwent TAVR and were admitted directly to the CD according to a prespecified protocol (uncomplicated procedure, hemodynamically stable, without new conduction abnormalities) in 2017-2018, and the same number of patients meeting the same criteria who were admitted to the CICU in 2015-2016 before direct CD admission was initiated. Pacemaker implantation during the procedure was not considered a new conduction abnormality. In-hospital outcomes and 30-day post-discharge outcomes were compared.

RESULTS

Overall, 260 patients (130 CICU + 130 CD) were included in the study. There was no in-hospital mortality in either group, and the post-procedure length of stay was shorter for patients admitted to CD (median and IQR: 2, 2-4 vs. 4, 3-5 days, p <0.001). There was no significant difference in 30-day emergency department visits between groups (CICU:13.9% vs. CD:16.2%, p = 0.602), rehospitalization rate (9.3%) was the same in both groups, and one patient from the CICU group died. Similar results were observed in multivariable analysis and after matching.

CONCLUSION

Direct admission to the CD after TAVR, according to the proposed criteria, may be considered as a safe and less expensive alternative for stable patients after an uncomplicated TAVR procedure.

TAVI after More Than 20 Years

It has been more than 20 years since the first in man transcatheter aortic valve intervention (TAVI), and during this period we have witnessed an impressive evolution of this technique, with an extension of its use from non-operable patients to high-, intermediate- and even low-risk patients with aortic stenosis, and with a decrease in the incidence of complications. In this review, we discuss the evaluation of patients before TAVI, the procedure and the changes it has seen over time, and we present the current main complications and challenges of TAVI.

Temporal validation of 30-day mortality prediction models for transcatheter aortic valve implantation using statistical process control - An observational study in a national population

Background

Various mortality prediction models for Transcatheter Aortic Valve Implantation (TAVI) have been developed in the past years. The effect of time on the performance of such models, however, is unclear given the improvements in the procedure and changes in patient selection, potentially jeopardizing the usefulness of the prediction models in clinical practice. We aim to explore how time affects the performance and stability of different types of prediction models of 30-day mortality after TAVI.

Methods

We developed both parametric (Logistic Regression) and non-parametric (XGBoost) models to predict 30-day mortality after TAVI using data from the Netherlands Heart Registration. The models were trained with data from 2013 to the beginning of 2016 and pre-control charts from Statistical Process Control were used to analyse how time affects the models' performance on independent data from the mid of 2016 to the end of 2019. The area under the Receiver Operating Characteristics curve (AUC) was used to evaluate the models in terms of discrimination and the Brier Score (BS), which is related to calibration, in terms of accuracy of the predicted probabilities. To understand the extent to which refitting the models contribute to the models' stability, we also allowed the models to be updated over time.

Results

We included data from 11,291 consecutive TAVI patients from hospitals in the Netherlands. The parametric model without re-training had a median AUC of 0.64 (IQR 0.54-0.73) and BS of 0.028 (IQR 0.021-0.035). For the non-parametric model, the median AUC was 0.63 (IQR 0.48-0.68) and BS was 0.027 (IQR 0.021-0.036). Over time, the developed parametric model was stable in terms of AUC and unstable in terms of BS. The non-parametric model was considered unstable in both AUC and BS. Repeated model refitting resulted in stable models in terms of AUC and decreased the variability of BS, although BS was still unstable. The refitted parametric model had a median AUC of 0.66 (IQR 0.57-0.73) and BS of 0.027 (IQR 0.020-0.035) while the non-parametric model had a median AUC of 0.66 (IQR 0.57-0.74) and BS of 0.027 (IQR 0.023-0.035).

Conclusions

The temporal validation of the TAVI 30-day mortality prediction models showed that the models refitted over time are more stable and accurate when compared to the frozen models. This highlights the importance of repeatedly refitted models over time to improve or at least maintain their performance stability. The non-parametric approach did not show improvement over the parametric approach.

OUP accepted manuscript

Transcatheter aortic valve implantation (TAVI) varies considerably in terms of the procedural approach taken and the hospital length of stay (LoS); both directly affect the cost of care. Our coronary and standard cardiology unit aimed to simplify TAVI (and thus shorten the LoS) while maintaining safety. A shorter LoS would also reduce the burden on hospital resources and free up beds for other patients. Data on 214 consecutive patients undergoing TAVI at a single centre between April 2018 and March 2021 were retrospectively collected. A simplified protocol was implemented in January 2020; patients were stratified by whether they underwent TAVI before or after simplification. All procedural phases were simplified. For cost comparison purposes, the LoS was defined as the number of hospitalization days from admission to discharge. The total hospitalization cost was the sum of the direct and indirect (including reallocated overhead) costs. The LoS fell significantly (by 36%) after TAVI simplification. The times in the coronary care unit (CCU) and standard cardiac unit (SCU) also fell significantly (by 33% and 37% respectively). Patients in the simplified TAVI group were discharged, on average, 6 days after admission. The CCU costs decreased by 31% and the SCU costs by 39%. Transcatheter aortic valve implantation simplification did not compromise safety. Indeed, patients who underwent the simplified procedure seemed to develop fewer complications, especially bleeding. Transcatheter aortic valve implantation simplification significantly reduced the LoS and other costs without compromising patient safety.

Setting a benchmark for resource utilization and quality of care in patients undergoing transcatheter aortic valve implantation in Europe-Rationale and design of the international BENCHMARK registry

Background

The use of transcatheter aortic valve implantation (TAVI) for treating aortic stenosis (AS) has increased exponentially in recent years. Despite the availability of clinical practice guidelines for the management of valvular heart disease, disparities in quality of care (QoC) for TAVI patients remain widespread across Europe. Tailored QoC measures will help to reduce resource utilization and improve patient outcomes without compromising patient safety. Using a clear set of QoC measures, the BENCHMARK registry aims to document the progress that can be achieved if such tailored QoC measures are implemented.

Methods

The BENCHMARK registry (BENCHMARK) is a non‐interventional, multicenter registry in patients with severe symptomatic AS undergoing TAVI with a 1‐ and 12‐months follow‐up. BENCHMARK will be conducted at 30 centers across Europe and will enroll a total of 2400 consecutive TAVI patients. Patients suffering from severe symptomatic AS who undergo TAVI with a balloon‐expandable transcatheter aortic valve will be included. The registry will comprise four phases: (1) a retrospective baseline evaluation phase; (2) an education phase; (3) an implementation phase; and (4) a prospective effect documentation phase (prospective phase). The registry's primary objectives are to reduce the length of hospital stay and accelerate the post‐procedural patient recovery pathway, but without compromising safety. The study started in April 2021 and has an estimated completion date of May 2023.

Discussion

BENCHMARK will establish QoC measures to reduce resource utilization, intensive care unit bed occupancy, and overall length of hospitalization with uncompromised patient safety post‐TAVI (ClinicalTrials.gov Identifier: NCT04579445).

Highlights

The BENCHMARK registry is a non‐interventional, multicenter international registry.

A total of 2400 patients with severe AS will be enrolled at 30 European centers.

The registry is designed to be partly retrospective and partly prospective.

The BENCHMARK registry will help to improve TAVI QoC standards across Europe.

How the COVID-19 pandemic changed treatment of severe aortic stenosis: a single cardiac center experience

Background

Currently, two effective therapeutic options for severe aortic stenosis (AS) are available, one catheter-based [transcatheter aortic valve implantation (TAVI)], the other open surgical approach [surgical aortic valve replacement (SAVR)]. The COVID-19 pandemic has limited the availability of medical procedures. The purpose of this cross-sectional study was to assess if this pandemic had any impact on the treatment strategy of severe AS in a single cardiac center.

Methods

This study involved AS patients treated in 3-month periods (February through April) over 3 consecutive years 2018, 2019 [defined as COV(-) group] and 2020 [COV(+)]. We assessed if there were any differences regarding patients' clinical profile, applied therapeutic method, procedure complexity and early clinical outcomes.

Results

In the years 2018 through 2019, approximately 50% of AS patients were treated classically (SAVR) while in 2020 this rate dropped to 34%. The preoperative clinical characteristic of TAVI subjects was comparable irrespective of the year. Regarding SAVR, more patients in COV(+) underwent urgent and more complex procedures. More of them were found in NYHA class III or IV, and had lower left ventricular ejection fraction (LVEF) (51.9%±14.4% vs. 58.3%±8.1%; P=0.021) than in COV(-) individuals. During the pandemic, a change in applied therapeutic methods and differences in patients' clinical profile did not have an unfavorable impact on in-hospital mortality (2.0% before vs. 3.6% during pandemic) and morbidity. Of note, intubation time and in-hospital stay were significantly shorter (P<0.05) in 2020 (4.2 hours and 7.5 days) than in the previous years (7.5 hours and 9.0 days, respectively).

Conclusions

The coronavirus pandemic has changed substantially the management of severe AS. The shift into less invasive treatment method of AS patients resulted in shortening of in-hospital stay without compromise of short-term outcomes.

Evaluation of procedural and clinical outcomes of transcatheter aortic valve implantation: A single-center experience

Objective:

Transcatheter aortic valve implantation (TAVI) is an established alternative to surgical aortic valve replacement. Our study aimed to evaluate the implementation of TAVI at our large-volume center, having an all-comer patient population with short and long-term follow-ups.

Methods:

This retrospective, single-center analysis included 556 consecutive patients with symptomatic severe aortic stenosis (AS) who underwent TAVI between July 2011 and December 2019.

Results:

The mean age of the entire population was 77.6±7.9 years, and 54.9% were women. The Society of Thoracic Surgeons (STS) mean score of the cohort was 6.0%±3.5%. The balloon-expandable valve (Sapien XT, Sapien 3; Edwards Lifesciences, Irvine, California) was the most frequently used valves in this cohort (94.6%). Transfemoral access was used in 96.3% of patients. Implantation success was achieved in 96.6% of cases. During the TAVI procedure, 7.2% of patients required permanent pacemaker implantation, with 37.5% in the Lotus valve group needing the most permanent pacemakers. The mean length of hospital stay for the entire cohort was 4.5±2.3 days. Overall, 22 (3.9%) in-hospital deaths occurred before hospital discharge. The mean follow-up period was 15.1±14.9 months for all patients, and a significant improvement was noted in all echocardiographic parameters and functional capacity. Paravalvular leak (PVL) was documented in 18.9% patients, mild in 17.9%, and moderate in 1% at discharge. No cases with severe PVL, necessitating additional procedures. The multiple logistic regression analysis revealed that sex, STS score, baseline SYNTAX score, bicuspid valve morphology, common femoral artery diameter, and post-TAVI PVL were independent predictors of overall mortality.

Conclusion:

To our knowledge, this study, which is the largest single-center real-world experience of TAVI in Turkey, demonstrated low complication rates with favorable short- and mid-term THV performance in patients undergoing TAVI.

Myocardial Injury After Balloon Predilatation Versus Direct Transcatheter Aortic Valve Replacement: Insights From the DIRECTAVI Trial

Background Myocardial injury is associated with higher mortality after transcatheter aortic valve replacement (TAVR) and might be increased by prior balloon aortic valvuloplasty (BAV). We aimed to evaluate the impact of prior BAV versus direct prosthesis implantation on myocardial injury occurring after (TAVR) with balloon-expandable prostheses. Methods and Results The DIRECTAVI (Direct Transcatheter Aortic Valve Implantation) trial, an open-label randomized study, demonstrated noninferiority of TAVR without BAV (direct TAVR group) compared with systematic BAV (BAV group) with the Edwards SAPIEN 3 valve. High-sensitivity troponin was assessed before and the day after the procedure. Incidence of myocardial injury after the procedure (high-sensitivity troponin elevation >15× the upper reference limit [14 ng/L]) was the main end point. Impact of myocardial injury on 1-month adverse events (all-cause mortality, stroke, major bleeding, major vascular complications, transfusion, acute kidney injury, heart failure, pacemaker implantation, and aortic regurgitation) was evaluated. Preprocedure and postprocedure high-sensitivity troponin levels were available in 211 patients. The mean age of patients was 83 years (78-87 years), with 129 men (61.1%). Mean postprocedure high-sensitivity troponin was 124.9±81.4 ng/L in the direct TAVR group versus 170.4±127.7 ng/L in the BAV group (P=0.007). Myocardial injury occurred in 42 patients (19.9%), including 13 patients (12.2%) in the direct TAVR group and 29 (27.9%) in the BAV group (P=0.004). BAV increased by 2.8-fold (95% CI, 1.4-5.8) myocardial injury probability. Myocardial injury was associated with 1-month adverse events (P=0.03). Conclusions BAV increased the incidence and magnitude of myocardial injury after TAVR with new-generation balloon-expandable valves. Myocardial injury was associated with 1-month adverse events. These results argue in favor of direct SAPIEN 3 valve implantation. Registration URL: https://www.Clinicaltrials.gov; Unique identifier: NCT02729519.

Transcatheter aortic valve replacement: potential use in lower-risk aortic stenosis

INTRODUCTION

The widespread use of transcatheter aortic valve implantation (TAVI) is expanding to low-risk patients. Nevertheless, a low clinical risk does not always correspond to a low procedural risk for the percutaneous approach.

AREAS COVERED

The initial trials on TAVI in low-risk populations had encouraging results, showing non-inferiority in comparison to surgical aortic valve replacement (SAVR). However, the low-risk definition is based on risk score calculators developed for the surgical setting and not including other specific features that are more relevant to TAVI and can affect procedural outcomes. For example, the presence of bicuspid aortic valves, high calcific burden, low coronary height or conduction disturbances is all potentially associated with suboptimal results or even procedural complications. In addition, the lack of longer follow-up prevents us to draw conclusions about long-term outcomes, including data about valve durability and coronary re-access.

EXPERT OPINION

Although current evidence suggest similar results for TAVI and SAVR in low-risk populations, there are some technical and procedural limitations that still need to be addressed in order to close the gap between TAVI and surgery. Optimal, lasting results with a low rate of procedural complications are highly expected in low-risk, otherwise healthy subjects, with potential for longevity.

Comparison of the self-expanding Evolut-PRO transcatheter aortic valve to its predecessor Evolut-R in the real world multicenter ATLAS registry

BACKGROUND

The Evolut PRO self-expanding transcatheter aortic valve has been designed to feature an outer pericardial wrap that aims to reduce paravalvular regurgitation (PVR) rates. Medium-term clinical outcomes, compared to its predecessor Evolut R, in a real-world setting, have not been investigated. The aim of the present study was to compare the two valves with regards to peri-procedural complications, early outcomes and mid-term survival.

METHODS

Consecutive patients, undergoing TAVI with either the Evolut PRO or Evolut R device, from the multicenter ATLAS registry were retrospectively studied. Outcomes studied included periprocedural complications, PVR at discharge, need for new pacemaker implantation and Kaplan-Meier estimated 1-year all-cause mortality.

RESULTS

Analysis included 673 patients (498 treated with Evolut R and 175 treated with Evolut PRO). At least moderate PVR was numerically lower amongst patients treated with Evolut PRO (7.4% vs 3.8% for Evolut R and Evolut PRO respectively, p = .108). Rates of new permanent pacemaker (PPM) implantation (21.1% vs. 11.9%, p = .023), and bail-out valve-in-valve (2.4% vs. 0%, p = .049) were significantly lower amongst the Evolut PRO group. No differences were demonstrated regarding bleeding, stroke or acute kidney injury. One-year Kaplan-Meier estimated survival was similar between groups (93% for Evolut R vs. 91.2% for Evolut PRO, p_log-rank = 0.806).

CONCLUSIONS

The Evolut PRO self-expanding valve demonstrates similar mid-term survival rates and numerically, yet not significant, lower incidence of PVR compared to its predecessor. Interestingly this new generation valve is associated with a significantly reduced rate for new PPM implantation. Future studies are required to confirm this finding.

Transcatheter Aortic Valve Replacement versus Surgical Aortic Valve Replacement: A Review of Aortic Stenosis Management

Severe aortic stenosis (AS) affects 3.4% of the elderly over 60 years of age. It presents with exertional dyspnea, syncope, angina, and progression to irreversible congestive heart failure. Early intervention produces a better outcome in preventing the clinical deterioration of AS. The choice of intervention is transcatheter aortic valve implantation or surgical aortic valve replacement (SAVR). The decision should be made after evaluating an individual case based on its clinical features and the user’s experience with transcatheter aortic valve replacement (TAVR). We reviewed available data to illustrate the types of ASs, the background of interventions, current guidelines for TAVR, and its comparison with SAVR in terms of adverse effects.

[TAVI simplification: A focus]

After a first procedure carried out in 2002 by Pr Cribier's, Transcatheter Aortic Valve Replacement or TAVR revolutionized the management of aortic stenosis with a constant increase in the number of procedures performed worldwide. Experience of operators and teams and evolution of the technique has been accompanied by a drastic reduction in complications in patients at lower surgical risk. In parallel, the procedure was considerably simplified, carried out more and more under local anesthesia, with percutaneous femoral approach, secondary radial approach, prosthesis implantation without predilatation, rapid pacing on left ventricle wire and early discharge. Thus, the "simplified" TAVR adopted in most centers nowadays is a real revolution of the technique. However, simplified TAVR must be accompanied upstream by a rigorous selection of patients who can benefit from a minimalist procedure in order to guarantee its safety.

[TAVI in women, very encouraging results]

The population of elderly patients comprises a high percentage of women. This population is more vulnerable due to the presence of numerous comorbidities and is, therefore, particularly exposed to the risk of aortic valve degeneration, resulting in aortic valve stenosis whose symptoms are predictors of poor short-term outcomes. In the presence of symptomatic aortic stenosis, the recommended therapeutic option in this vulnerable population is the implementation of transcatheter aortic valve implantation, preferably via the femoral route. The outcomes of this procedure are better in women than in men despite a more frequent occurrence of vascular, bleeding and cerebral complications. Several hypotheses have been reported in the literature regarding the reasons for such differences. Among other reasons, it is likely that in female patients, the myocardium adjusts better to the occurrence of aortic stenosis and that recovery after valve treatment is also more optimal. Another explanation is the higher frequency of coronary artery disease in this older population. This has a considerable impact on the outcome even when coronary lesions are treated prior to valve implantation. There is still room for improvement and progress can be achieved by further reducing the size of the equipment used in order to decrease the diameter of the vascular access, and by continuing to simplify TAVI procedures. Less invasive techniques should result in decreased complication rates. In addition, dedicated studies should allow us to further improve our practice in this growing population of vulnerable patients.