Comparison of surgical versus transcatheter aortic valve replacement for patients with aortic stenosis at low-intermediate risk

Double crosslinking decellularized bovine pericardium of dialdehyde chondroitin sulfate and zwitterionic copolymer for bioprosthetic heart valves with enhanced antithrombogenic, anti-inflammatory and anti-calcification properties

Due to the increasing aging population and the advancements in transcatheter aortic valve replacement (TAVR), the use of bioprosthetic heart valves (BHVs) in patients diagnosed with valvular disease has increased substantially. Commercially available glutaraldehyde (GA) cross-linked biological valves suffer from reduced durability due to a combination of factors, including the high cell toxicity of GA, subacute thrombus, inflammation and calcification. In this study, oxidized chondroitin sulfate (OCS), a natural polysaccharide derivative, was used to replace GA to cross-link decellularized bovine pericardium (DBP), carrying out the first crosslinking of DBP to obtain OCS-BP. Subsequently, the zwitterion radical copolymerization system was introduced in situ to perform double cross-linking to obtain double crosslinked BHVs with biomimetic modification (P(APM/MPC)-OCS-BP). P(APM/MPC)-OCS-BP presented enhanced mechanical properties, collagen stability and enzymatic degradation resistance due to double crosslinking. The ex vivo AV-shunt assay and coagulation factors test suggested that P(APM/MPC)-OCS-BP exhibited excellent anticoagulant and antithrombotic properties due to the introduction of P(APM/MPC). P(APM/MPC)-OCS-BP also showed good HUVEC-cytocompatibility due to the substantial reduction of its residual aldehyde group. The subcutaneous implantation also demonstrated that P(APM/MPC)-OCS-BP showed a weak inflammatory response due to the anti-inflammatory effect of OCS. Finally, in vivo and in vitro results revealed that P(APM/MPC)-OCS-BP exhibited an excellent anti-calcification property. In a word, this simple cooperative crosslinking strategy provides a novel solution to obtain BHVs with good mechanical properties, and HUVEC-cytocompatibility, anti-coagulation, anti-inflammatory and anti-calcification properties. It might be a promising alternative to GA-fixed BP and exhibited good prospects in clinical applications.

Native aortic leaflets and permanent pacemaker implantation risk following balloon-expandable transcatheter aortic valve implantation

OBJECTIVE

Permanent pacemaker implantation (PPI) risk is higher following transcatheter aortic valve implantation (TAVI) than surgical valve replacement. Native aortic leaflets are retained in patients undergoing TAVI, unlike in surgical valve replacement. Whether the retained leaflets influence PPI risk because of their proximity to the conduction system is unknown. The study sought to determine the association between infra-annular extension of native right coronary cusp/noncoronary cusp (RCC/NCC) post balloon-expandable TAVI and PPI risk.

METHODS

We performed a retrospective analysis of 190 patients undergoing balloon-expandable TAVI at a single center. Manifestation of infra-annular extension of RCC/NCC was considered to be present when part of leaflet extended below aortic-annular plane on post-implantation aortic-root angiography.

RESULTS

Infra-annular extension of RCC/NCC was observed in 33 patients (17.37%). PPI incidence post-TAVI was higher in patients with infra-annular extension of RCC/NCC than in those without (36.36% versus 8.92%, relative-risk: 4.08, p˂0.0001). On logistic-regression analysis, preexisting right bundle-branch block (RBBB) (odds-ratio: 12.73, 95% confidence-interval: 2.16-74.93, p = 0.005), and infra-annular extension of RCC/NCC (odds-ratio: 5.63, 95% confidence-interval: 2.17-14.58, p < 0.0001) were independently associated with PPI risk. Preexisting RBBB (φ = +0.25, p = 0.001) and infra-annular extension of RCC/NCC (φ = +0.30, p < 0.0001) showed a positive-correlation with PPI risk. Infra-annular extension of RCC/NCC was a significant predictor of PPI risk on receiver-operating-characteristic curve analysis (area under-the-curve 0.67; 95% confidence-interval: 0.54-0.79, p = 0.006).

CONCLUSION

The retained native aortic leaflets play a significant role in PPI risk following balloon-expandable TAVI. Infra-annular extension of RCC/NCC is a novel predictor, and is associated with a four-fold higher risk of PPI.

Risk and protective factors for atrial fibrillation after cardiac surgery and valvular interventions: an umbrella review of meta-analyses

Objective

Postoperative atrial fibrillation (POAF) is a common complication affecting approximately one-third of patients after cardiac surgery and valvular interventions. This umbrella review systematically appraises the epidemiological credibility of published meta-analyses of both observational and randomised controlled trials (RCT) to assess the risk and protective factors of POAF.

Methods

Three databases were searched up to June 2021. According to established criteria, evidence of association was rated as convincing, highly suggestive, suggestive, weak or not significant concerning observational studies and as high, moderate, low or very low regarding RCTs.

Results

We identified 47 studies (reporting 61 associations), 13 referring to observational studies and 34 to RCTs. Only the transfemoral transcatheter aortic valve replacement (TAVR) approach was associated with the prevention of POAF and was supported by convincing evidence from meta-analyses of observational data. Two other associations provided highly suggestive evidence, including preoperative hypertension and neutrophil/lymphocyte ratio. Three associations between protective factors and POAF presented a high level of evidence in meta-analyses, including RCTs. These associations included atrial and biatrial pacing and performing a posterior pericardiotomy. Nineteen associations were supported by moderate evidence, including use of drugs such as amiodarone, b-blockers, glucocorticoids and statins and the performance of TAVR compared with surgical aortic valve replacement.

Conclusions

Our study provides evidence confirming the protective role of amiodarone, b-blockers, atrial pacing and posterior pericardiotomy against POAF as well as highlights the risk of untreated hypertension. Further research is needed to assess the potential role of statins, glucocorticoids and colchicine in the prevention of POAF.

PROSPERO registration number

CRD42021268268.

Transcatheter aortic valve implantation versus surgical aortic valve replacement in patients with severe aortic stenosis: a systematic review and meta-analysis

OBJECTIVES

Patients undergoing surgery for severe aortic stenosis (SAS) can be treated with either transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR). The choice of procedure depends on several factors, including the clinical judgement of the heart team and patient preferences, which are captured by actively informing and involving patients in a process of shared decision making (SDM). We synthesised the most up-to-date and accessible evidence on the benefits and risks that may be associated with TAVI versus SAVR to support SDM in this highly personalised decision-making process.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

MEDLINE (Ovid), Embase (Ovid) and the Cochrane Central Register of Controlled Trials (CENTRAL; Wiley) were searched from January 2000 to August 2020 with no language restrictions. Reference lists of included studies were searched to identify additional studies.

ELIGIBILITY CRITERIA

Randomised controlled trials (RCTs) that compared TAVI versus SAVR in patients with SAS and reported on all-cause or cardiovascular mortality, length of stay in intensive care unit or hospital, valve durability, rehospitalisation/reintervention, stroke (any stroke or major/disabling stroke), myocardial infarction, major vascular complications, major bleeding, permanent pacemaker (PPM) implantation, new-onset or worsening atrial fibrillation (NOW-AF), endocarditis, acute kidney injury (AKI), recovery time or pain were included.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers were involved in data extraction and risk of bias (ROB) assessment using the Cochrane tool (one reviewer extracted/assessed the data, and the second reviewer checked it). Dichotomous data were pooled using the Mantel-Haenszel method with random-effects to generate a risk ratio (RR) with 95% CI. Continuous data were pooled using the inverse-variance method with random-effects and expressed as a mean difference (MD) with 95% CI. Heterogeneity was assessed using the I² statistic.

RESULTS

8969 records were retrieved and nine RCTs (61 records) were ultimately included (n=8818 participants). Two RCTs recruited high-risk patients, two RCTs recruited intermediate-risk patients, two RCTs recruited low-risk patients, one RCT recruited high-risk (≥70 years) or any-risk (≥80 years) patients; and two RCTs recruited all-risk or 'operable' patients. While there was no overall change in the risk of dying from any cause (30 day: RR 0.89, 95% CI 0.65 to 1.22; ≤1 year: RR 0.90, 95% CI 0.79 to 1.03; 5 years: RR 1.09, 95% CI 0.98 to 1.22), cardiovascular mortality (30 day: RR 1.03, 95% CI 0.77 to 1.39; ≤1 year: RR 0.90, 95% CI 0.76 to 1.06; 2 years: RR 0.96, 95% CI 0.83 to 1.12), or any type of stroke (30 day: RR 0.83, 95% CI 0.61 to 1.14;≤1 year: RR 0.94, 95% CI 0.72 to 1.23; 5 years: RR 1.07, 95% CI 0.88 to 1.30), the risk of several clinical outcomes was significantly decreased (major bleeding, AKI, NOW-AF) or significantly increased (major vascular complications, PPM implantation) for TAVI vs SAVR. TAVI was associated with a significantly shorter hospital stay vs SAVR (MD -3.08 days, 95% CI -4.86 to -1.29; 4 RCTs, n=2758 participants). Subgroup analysis generally favoured TAVI patients receiving implantation via the transfemoral (TF) route (vs non-TF); receiving a balloon-expandable (vs self-expanding) valve; and those at low-intermediate risk (vs high risk). All RCTs were rated at high ROB, predominantly due to lack of blinding and selective reporting.

CONCLUSIONS

No overall change in the risk of death from any cause or cardiovascular mortality was identified but 95% CIs were often wide, indicating uncertainty. TAVI may reduce the risk of certain side effects while SAVR may reduce the risk of others. Most long-term (5-year) results are limited to older patients at high surgical risk (ie, early trials), therefore more data are required for low risk populations. Ultimately, neither surgical technique was considered dominant, and these results suggest that every patient with SAS should be individually engaged in SDM to make evidence-based, personalised decisions around their care based on the various benefits and risks associated with each treatment.

PROSPERO REGISTRATION NUMBER

CRD42019138171.

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.

The International Society for Minimally Invasive Cardiothoracic Surgery Expert Consensus Statement on Transcatheter and Surgical Aortic Valve Replacement in Low- and Intermediate-Risk Patients: A Meta-Analysis of Randomized and Propensity-Matched Studies

OBJECTIVE

There is an increasing amount of evidence supporting use of transcatheter aortic valve replacement (TAVR) for treatment of aortic stenosis in patients at low or intermediate risk for surgical aortic valve replacement (SAVR). TAVR is now approved for use in all patient cohorts. Despite this, there remains debate about the relative efficacy of TAVR compared with SAVR in lower-risk cohorts and various subgroups of patients. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) and propensity-matched trials to guide a consensus among expert cardiologists and surgeons.

METHODS

Studies comparing TAVR and SAVR in low- and intermediate-risk patients were identified by a thorough search of the major databases. Mortality, stroke, and other perioperative outcomes were assessed at 30 days and 1 year.

RESULTS

Early mortality was lower in TAVR compared to SAVR in RCTs, but not propensity-matched studies in low-risk cohorts (0.66% vs 1.5%; odds ratio [OR] = 0.44, 95% confidence interval [CI] 0.20 to 0.98, I² = 0%). No difference in mortality between TAVR and SAVR was identified in intermediate-risk patients at early or later time points. Incidence of perioperative stroke in 3 low-risk RCTs was significantly lower in TAVR (0.4%) than SAVR (1.4%; OR = 0.33, 95% CI 0.13 to 0.81, I² = 0%). There was no difference in stroke for intermediate-risk patients between TAVR and SAVR. The expert panel of cardiologists and cardiac surgeons provided recommendations for TAVR and SAVR in various clinical scenarios.

CONCLUSIONS

In RCTs comparing TAVR and SAVR in low-risk patients, early mortality and stroke were lower in TAVR, but did not differ at 1 year. There was no difference in mortality and stroke in intermediate-risk patients. The Multidisciplinary Heart Team must consider individual patient characteristics and preferences when recommending TAVR or SAVR. The decision must consider the long-term management of each patient's aortic valve disease.