Comparison of transcatheter aortic valve implantation with other approaches to treat aortic valve stenosis: a systematic review and meta-analysis

Transcatheter Aortic Valve Implantation and Cardiac Conduction Abnormalities: Prevalence, Risk Factors and Management

Over the last decades, transcatheter aortic valve implantation (TAVI) or replacement (TAVR) has become a potential, widely accepted, and effective method of treating aortic stenosis in patients at moderate and high surgical risk and those disqualified from surgery. The method evolved what translates into a noticeable decrease in the incidence of complications and more beneficial clinical outcomes. However, the incidence of conduction abnormalities related to TAVI, including left bundle branch block and complete or second-degree atrioventricular block (AVB), remains high. The occurrence of AVB requiring permanent pacemaker implantation is associated with a worse prognosis in this group of patients. The identification of risk factors for conduction disturbances requiring pacemaker placement and the assessment of their relation to pacing dependence may help to develop methods of optimal care, including preventive measures, for patients undergoing TAVI. This approach is crucial given the emerging evidence of no worse outcomes for intermediate and low-risk patients undergoing TAVI in comparison to surgical aortic valve replacement. This paper comprehensively discusses the mechanisms, risk factors, and consequences of conduction abnormalities and arrhythmias, including AVB, atrial fibrillation, and ventricular arrhythmias associated with aortic stenosis and TAVI, as well as provides insights into optimized patient care, along with the potential of conduction system pacing and cardiac resynchronization therapy, to minimize the risk of unfavorable clinical outcomes.

Effectiveness of aortic valve replacement in Heyde syndrome: a meta-analysis

AIMS

Heyde syndrome is the co-occurrence of aortic stenosis, acquired von Willebrand syndrome, and gastrointestinal bleeding. Aortic valve replacement has been demonstrated to resolve all three associated disorders. A systematic review and meta-analysis were performed to obtain best estimates of the effect of aortic valve replacement on acquired von Willebrand syndrome and gastrointestinal bleeding.

METHODS AND RESULTS

A literature search was performed to identify articles on Heyde syndrome and aortic valve replacement up to 25 October 2022. Primary outcomes were the proportion of patients with recovery of acquired von Willebrand syndrome within 24 h (T1), 24-72 h (T2), 3-21 days (T3), and 4 weeks to 2 years (T4) after aortic valve replacement and the proportion of patients with cessation of gastrointestinal bleeding. Pooled proportions and risk ratios were calculated using random-effects models. Thirty-three studies (32 observational studies and one randomized controlled trial) on acquired von Willebrand syndrome (n = 1054), and 11 observational studies on gastrointestinal bleeding (n = 300) were identified. One study reported on both associated disorders (n = 6). The pooled proportion of Heyde patients with acquired von Willebrand syndrome recovery was 86% (95% CI, 79%-91%) at T1, 90% (74%-96%) at T2, 92% (84%-96%) at T3, and 87% (67%-96%) at T4. The pooled proportion of Heyde patients with gastrointestinal bleeding cessation was 73% (62%-81%). Residual aortic valve disease was associated with lower recovery rates of acquired von Willebrand syndrome (RR 0.20; 0.05-0.72; P = 0.014) and gastrointestinal bleeding (RR 0.57; 0.40-0.81; P = 0.002).

CONCLUSION

Aortic valve replacement is associated with rapid recovery of the bleeding diathesis in Heyde syndrome and gastrointestinal bleeding cessation. Residual valve disease compromises clinical benefits.

Chronological comparison of TAVI and SAVR stratified to surgical risk: a systematic review, meta-analysis, and meta-regression

BACKGROUND

Transcatheter aortic valve implantation (TAVI) has been established as a reasonable alternative to surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis. However, long-term outcomes including valve durability and the need for reintervention are unanswered, especially in younger patients who tend to be low surgical risk. We performed a meta-analysis comparing clinical outcomes after TAVI and SAVR over 5 years stratified to low, intermediate, and high surgical risks.

METHODS

We identified propensity score-matched observational studies and randomised controlled trials comparing TAVI and SAVR. Primary outcomes, including all-cause mortality, moderate or severe aortic regurgitation, moderate or severe paravalvular regurgitation, pacemaker placement, and stroke, were extracted. Meta-analyses of outcomes after TAVI compared to SAVR were conducted for different periods of follow-up. Meta-regression was also performed to analyse the correlation of outcomes over time.

RESULTS

A total of 36 studies consisting of 7 RCTs and 29 propensity score-matched studies were selected. TAVI was associated with higher all-cause mortality at 4-5 years in patients with low or intermediate surgical risk. Meta-regression time demonstrated an increasing trend in the risk of all-cause mortality after TAVI compared with SAVR. TAVI was generally associated with a higher risk of moderate or severe aortic regurgitation, moderate or severe paravalvular regurgitation, and pacemaker placement.

CONCLUSIONS

TAVI demonstrated an increasing trend of all-cause mortality compared with SAVR when evaluated over a long-term follow-up. More long-term data from recent studies using newer-generation valves and state-of-the-art techniques are needed to accurately assign risks.

Left Atrial Appendage Closure: What the Evidence Does and Does Not Reveal-A View from the Outside

This review summarizes the evidence for left atrial appendage closure (LAAC) as an alternative to oral anticoagulation (OAC) for stroke prevention in atrial fibrillation. LAAC reduces hemorrhagic stroke and mortality versus warfarin, but is inferior for ischemic stroke reduction based on randomized data. Whilst a feasible treatment in OAC-ineligible patients, questions remain over procedural safety, and the improvement in complications observed in nonrandomized registries is uncorroborated by contemporary randomized trials. Management of device-related thrombus and peridevice leak remain unclear, and robust randomized data versus direct OACs are required before recommendations can be made for widespread adoption in OAC-eligible populations.

Reduction of Gastrointestinal Bleeding in Patients With Heyde Syndrome Undergoing Transcatheter Aortic Valve Implantation

BACKGROUND

Heyde syndrome is the co-occurrence of aortic stenosis and gastrointestinal bleeding secondary to angiodysplasias. Surgical aortic valve replacement effectively reduces bleeding, but the effects of transcatheter aortic valve implantation (TAVI) are largely unknown. This study aimed to describe the reduction of gastrointestinal bleeding in patients with Heyde syndrome after TAVI and to identify the factors associated with rebleeding.

METHODS

We enrolled patients with Heyde syndrome from a prospective TAVI registry. Gastrointestinal bleeding episodes were assessed by the Bleeding Academic Research Consortium classification, and cumulative incidence functions were used to calculate cessation rates. Factors potentially associated with rebleeding were analyzed using logistic regression. Differences between Heyde and non-Heyde patients were assessed through a case-cohort study.

RESULTS

Between December 2008 and June 2020, 1111 patients underwent TAVI. There were 70 patients with Heyde syndrome (6.3%). In the first year following TAVI, gastrointestinal bleeding ceased in 46 of 70 patients (62% [95% CI, 50%-74%]). Bleeding episodes decreased from 3.2 (95% CI, 2.5-4.2) to 1.6 ([95% CI, 1.2-2.2] P=0.001) and hemoglobin levels increased from 10.3 (95% CI, 10.0-10.8) to 11.3 (95% CI, 10.8-11.6) g/dL (P=0.007). Between 1 and 5 years after TAVI (35 [interquartile range, 21-51] months), 53 of 62 patients (83% [95% CI, 72%-92%]) no longer experienced gastrointestinal bleeding. Paravalvular leakage (≥mild) was associated with rebleeding risk (odds ratio, 3.65 [95% CI, 1.36-9.80]; P=0.010). Periprocedural bleeding was more common in Heyde than in control patients (adjusted odds ratio, 2.55 [95% CI, 1.37-4.73]; P=0.003).

CONCLUSIONS

Patients with Heyde syndrome are at increased risk for periprocedural bleeding. Post-TAVI, gastrointestinal bleeding disappears in the majority of patients. Paravalvular leakage may curtail these clinical benefits.

Left Atrial Appendage Closure: What the Evidence Does and Does Not Reveal-A View from the Outside

This review summarizes the evidence for left atrial appendage closure (LAAC) as an alternative to oral anticoagulation (OAC) for stroke prevention in atrial fibrillation. LAAC reduces hemorrhagic stroke and mortality versus warfarin, but is inferior for ischemic stroke reduction based on randomized data. Whilst a feasible treatment in OAC-ineligible patients, questions remain over procedural safety, and the improvement in complications observed in nonrandomized registries is uncorroborated by contemporary randomized trials. Management of device-related thrombus and peridevice leak remain unclear, and robust randomized data versus direct OACs are required before recommendations can be made for widespread adoption in OAC-eligible populations.

Predictors of Permanent Pacemaker Implantation in Patients Undergoing Transcatheter Aortic Valve Replacement - A Systematic Review and Meta-Analysis

Background

As transcatheter aortic valve replacement (TAVR) technology expands to healthy and lower‐risk populations, the burden and predictors of procedure‐related complications including the need for permanent pacemaker (PPM) implantation needs to be identified.

Methods and Results

Digital databases were systematically searched to identify studies reporting the incidence of PPM implantation after TAVR. A random‐ and fixed‐effects model was used to calculate unadjusted odds ratios (OR) for all predictors. A total of 78 studies, recruiting 31 261 patients were included in the final analysis. Overall, 6212 patients required a PPM, with a mean of 18.9% PPM per study and net rate ranging from 0.16% to 51%. The pooled estimates on a random‐effects model indicated significantly higher odds of post‐TAVR PPM implantation for men (OR, 1.16; 95% CI, 1.04–1.28); for patients with baseline mobitz type‐1 second‐degree atrioventricular block (OR, 3.13; 95% CI, 1.64–5.93), left anterior hemiblock (OR, 1.43; 95% CI, 1.09–1.86), bifascicular block (OR, 2.59; 95% CI, 1.52–4.42), right bundle‐branch block (OR, 2.48; 95% CI, 2.17–2.83), and for periprocedural atriorventricular block (OR, 4.17; 95% CI, 2.69–6.46). The mechanically expandable valves had 1.44 (95% CI, 1.18–1.76), while self‐expandable valves had 1.93 (95% CI, 1.42–2.63) fold higher odds of PPM requirement compared with self‐expandable and balloon‐expandable valves, respectively.

Conclusions

Male sex, baseline atrioventricular conduction delays, intraprocedural atrioventricular block, and use of mechanically expandable and self‐expanding prosthesis served as positive predictors of PPM implantation in patients undergoing TAVR.

Bias estimation in study design: a meta-epidemiological analysis of transcatheter versus surgical aortic valve replacement

BACKGROUND

Paucity of RCTs of non-drug technologies lead to widespread dependence on non-randomized studies. Relationship between nonrandomized study design attributes and biased estimates of treatment effects are poorly understood. Our purpose was to estimate the bias associated with specific nonrandomized study attributes among studies comparing transcatheter aortic valve implantation with surgical aortic valve replacement for the treatment of severe aortic stenosis.

RESULTS

We included 6 RCTs and 87 nonrandomized studies. Surgical risk scores were similar for comparison groups in RCTs, but were higher for patients having transcatheter aortic valve implantation in nonrandomized studies. Nonrandomized studies underestimated the benefit of transcatheter aortic valve implantation compared with RCTs. For example, nonrandomized studies without adjustment estimated a higher risk of postoperative mortality for transcatheter aortic valve implantation compared with surgical aortic valve replacement (OR 1.43 [95% CI 1.26 to 1.62]) than high quality RCTs (OR 0.78 [95% CI 0.54 to 1.11). Nonrandomized studies using propensity score matching (OR 1.13 [95% CI 0.85 to 1.52]) and regression modelling (OR 0.68 [95% CI 0.57 to 0.81]) to adjust results estimated treatment effects closer to high quality RCTs. Nonrandomized studies describing losses to follow-up estimated treatment effects that were significantly closer to high quality RCT than nonrandomized studies that did not.

CONCLUSION

Studies with different attributes produce different estimates of treatment effects. Study design attributes related to the completeness of follow-up may explain biased treatment estimates in nonrandomized studies, as in the case of aortic valve replacement where high-risk patients were preferentially selected for the newer (transcatheter) procedure.

Comparison of outcomes following transfemoral versus trans-subclavian approach for transcatheter aortic valve Implantation: A meta-analysis

BACKGROUND

The subclavian artery is an alternative access route for transcatheter aortic valve implantation (TAVI), with a potential advantage in patients unsuitable for traditional access routes such as the femoral artery. This study aimed to determine the safety and efficacy of the trans-subclavian (TSc) compared to the trans-femoral (TF) approach.

METHODS

A systematic review was conducted on two online databases: Embase and Medline. The initial search returned 508 titles. Nine observational studies were included: n = 2938 patients (2382 TF and 556 TSc).

RESULTS

Both TSc and TF groups were comparable for: 30-day mortality (Odds ratio, OR 0.75, 95% CI 0.49 - 1.16, p = 0.195); in-hospital stroke (OR 1.05, 95% CI 0.60-1.85, p = 0.859); myocardial infarction (OR 1.97, 95% CI 0.74-5.23, p = 0.176); paravalvular leaks (OR 1.20, 95% CI 0.76-1.90, p = 0.439); rates of postoperative permanent pacemaker implantation (OR 1.49, 95% CI 0.92-2.41, p = 0.105); in-hospital bleeding and meta-analysis demonstrated no significant difference between access points (OR 3.44, 95% CI 0.35-34.22, p = 0.292). Procedural time was found to be longer in the TSc group (SMD 1.02; 95% CI 0.815-1.219, p < 0.001). Major vascular complications were significantly higher in the TF group (OR 0.55, 95% CI 0.32-0.94, p = 0.029). Meta regression found no influence of the covariates on the outcomes.

CONCLUSION

Subclavian access is both a safe and feasible alternative access route for TAVI with lower risks of major vascular complications. This study supports the use of subclavian access as a viable alternative in patient groups where transfemoral TAVI is contraindicated.

Assessing the safety and efficacy of TAVR compared to SAVR in low-to-intermediate surgical risk patients with aortic valve stenosis: An overview of reviews

Background

Transcatheter aortic valve replacement (TAVR) was initially introduced to treat patients with aortic valve stenosis (AS) at high-risk for surgical aortic valve replacement (SAVR). Today, there is ample evidence supporting TAVR in high-risk groups. However, in recent years TAVR has been extended to low-to intermediate risk groups and relevant clinical evidence is still emerging, leaving some uncertainties.

Methods

To obtain information on TAVR versus SAVR in low-to intermediate risk groups, we conducted an overview of systematic reviews following PRISMA guidelines and based on a systematic search of EMBASE, MEDLINE, Cochrane and CRD databases. We focused on systematic reviews assessing mortality and VARC 2 as clinical outcomes.

Results

The majority of the 11 systematic reviews included in our study reported no differences in mortality between TAVR and SAVR at short and long-term follow-up times. Two reviews that included the most recent RCTs on low-risk patients reported a decreased mortality risk with TAVR at one-year follow-up. Regarding the secondary endpoints of stroke and MI, the majority of studies presented similar results for TAVR and SAVR. Acute Kidney Injury, Bleeding Complications, Atrial Fibrillation were less frequent with TAVR, with lower risk of Permanent Pacemaker Implantation and Aortic Regurgitation with SAVR.

Conclusions

Our overview indicated that TAVR is a promising intervention for low-to-intermediate surgical risk patients; however additional evidence from longer term follow-up is needed to confirm these findings. This overview highlights inconsistencies about reporting and presentation of data, most notably limited clarity on effects of risk of bias on trial results.

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We reviewed the evidence for TAVR and SAVR in low-to intermediate risk patients.

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Most reviews found no difference in mortality between TAVR and SAVR.

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Acute Kidney Injury, Bleeding and Atrial Fibrillation were less frequent with TAVR.

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Pacemaker Implantation and Aortic Regurgitation were less frequent with SAVR.

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Most reviews found no difference for Stroke and Myocardial Infarction.

The Use of Biological Heart Valves

BACKGROUND

Biological heart-valve prostheses have undergone continuous devel- opment up to the present, and technological advances have been made in catheter- assisted valve systems (transcatheter aortic valve implantation, TAVI) and minimally invasive routes of application. These parallel trends have led to major changes in therapeutic strategies, widening the spectrum of patients who are candidates for biological aortic valve implantation.

METHODS

This review is based on pertinent publications retrieved by a systematic search in PubMed employing the search terms "conventional biological aortic pros- thesis," "rapid deployment prosthesis," and "transcatheter aortic valve implantation/ replacement."

RESULTS

Among biological heart-valve prostheses, a distinction is drawn between stented (conventional, rapid-deployment, and catheter-assisted) and non-stented types. The long-term durability of conventional, surgically implantable biological valve protheses is by far the best documented: the reported 5-year reoperation rates range from 13.4% to 36.6%, and the pacemaker implantation rate is ca. 4%. Rapid-deployment prostheses combine the advantages of conventional and ca- theter-assisted techniques and facilitate minimally invasive approaches. The TAVI method is currently recommended for high- and intermediate-risk patients, while conventional valve replacement remains the method of choice for those at low risk. Rapid-deployment and TAVI prostheses is associated with a higher pacemaker im- plantation rate than conventional prostheses: these rates are 8.5-15.3% for TAVI and 6.0-8.8% for rapid-deployment valves. The intermediate-term durability of catheter-assisted and rapid-deployment prostheses appears promising, but their long-term durability is still unclear.

CONCLUSION

The further development of biological heart-valve prostheses in the form of improved conventional, transcatheter, and rapid-deployment prostheses now enables individualized treatment. Before any such procedure is performed, the car- diac team must assess the patient's risk profile and the advantages and disadvan- tages of each type of prosthesis to determine which is best.

Transcatheter Double Valve-in-Valve Replacement of Aortic and Mitral Bioprosthetic Valves

Transcatheter aortic valve replacement (TAVR) is an evolving method which has become the treatment of choice in high-risk patients with severe aortic stenosis. Unlike TAVR, the experience with transcatheter mitral valve replacement (TMVR) remains at an early stage because of challenges of valve development and possible complications such as valve displacement and subsequent left ventricular outlet tract (LVOT) obstruction. Here we report a case of transcatheter double valve-in-valve replacement (TDVIVR) in a patient with severe mitral and aortic bioprosthetic valve stenosis, followed by an extensive literature review of the latest techniques and challenges in this field.