Transcatheter vs Surgical Aortic Valve Replacement for Aortic Stenosis in Low-Intermediate Risk Patients: A Meta-analysis

Transcatheter interventions for valvular heart diseases in liver cirrhosis patients

There is an increasing prevalence of patients who have both liver cirrhosis (LC) and severe valvular heart disease. This combination typically poses prohibitive risk for liver transplantation. LC related malnourishment, hypoalbuminemia and hyperdynamic circulation places patients with severe LC at higher rates for significant bleeding and/or thrombosis, as well as infectious and renal complications, after either surgical or transcatheter valvular interventions. Although there remains scarce comparative evidence, the preponderance of data suggest that percutaneous strategies are preferred over surgical ones. A multidisciplinary team is ideal for identifying those patients with LC who would benefit from transcatheter valvular heart interventions.

Real-World Health-Economic Considerations Around Aortic-Valve Replacement in a Publicly Funded Health System

Herein, we describe the unique interplay among biomedical ethics, principles of distributive justice, and economic theory to highlight the role of health technology assessments to compare therapeutic options for aortic valve replacement. From the perspective of the Canadian health care system, transcatheter aortic-valve implantation is associated with higher costs but also higher incremental health benefits compared with surgical aortic-valve replacement. At current willingness to pay thresholds, transcatheter aortic-valve replacement is likely cost effective across the spectrum of risk, from inoperable patients to those at low surgical risk. However, we highlight the nuances within each subgroup of surgical risk that merit careful consideration by the heart team. Moreover, incorporation of patients and their preferences in decision-making is key. In particular, in young, low-risk patients, there remains uncertainty regarding the optimal treatment, with unique concerns around valve durability, selection of valve prosthesis, and consideration for special procedures such as the Ross procedure. Nonetheless, current research suggests that, universally, patients prefer a less invasive approach compared with a more invasive approach. Finally, we highlight that there remain critical issues around timeliness of access to care and unacceptable geographic inequities across Canada. Further research into alternative funding mechanisms and integrated cross-sector care pathways is necessary to address these issues.

Transcatheter vs surgical aortic valve replacement in low to intermediate surgical risk aortic stenosis patients: A systematic review and meta-analysis of randomized controlled trials

Background

Transcatheter aortic valve replacement (TAVR) is regarded as the most superior alternative treatment approach for patients with aortic stenosis (AS) who are associated with high surgical risk, whereas the effectiveness of TAVR vs surgical aortic valve replacement (SAVR) in low to intermediate surgical risk patients remained inconclusive. This study aimed to determine the best treatment strategies for AS with low to intermediate surgical risk based on published randomized controlled trials (RCTs).

Hypothesis and Methods

RCTs that compared TAVR vs SAVR in AS patients with low to intermediate surgical risk were identified by PubMed, EmBase, and the Cochrane library from inception till April 2019. The pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated for the data collected using random‐effects models.

Results

Seven RCTs with a total of 6929 AS patients were enrolled. We noted that TAVR significantly increased the risk of transient ischemic attack (TIA) (RR: 1.43; 95%CI: 1.04‐1.96; P = .029), and permanent pacemaker implantation (RR: 3.00; 95%CI: 1.70‐5.30; P < .001). However, TAVR was associated with lower risk of post‐procedural bleeding (RR: 0.57; 95%CI: 0.33‐0.98; P = .042), new‐onset or worsening of atrial fibrillation (RR: 0.32; 95%CI: 0.23‐0.45; P < .001), acute kidney injury (RR: 0.40; 95%CI: 0.25‐0.63; P < .001), and cardiogenic shock (RR: 0.34; 95%CI: 0.19‐0.59; P < .001). The risk of aortic‐valve reintervention at 1‐ (RR: 2.63; 95%CI: 1.34‐5.15; P = .005), and 2 years (RR: 3.19; 95%CI: 1.63‐6.24; P = .001) in low to intermediate surgical risk patients who received TAVR was significantly increased than those who received SAVR.

Conclusions

These findings indicated that low to intermediate surgical risk patients who received TAVR had low risk of complications, whereas the risk of TIA, permanent pacemaker implantation, and aortic‐valve reintervention was increased.

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.

Transcatheter aortic valve implantation in the patients with chronic liver disease: A mini-review and meta-analysis

BACKGROUND

Chronic liver disease is traditionally conceived as a risk factor for cardiovascular surgery. Transcatheter aortic valve implantation (TAVI) has recently burgeoned to precede surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis at intermediate to high surgical risk. The evidence regarding TAVI in the patients with chronic liver disease is currently scarce.

METHODS

This article aims to assess the application of TAVI technique in the patients with chronic liver disease.

RESULTS

TAVI in the patients with chronic liver disease produced acceptable postoperative results. The post-TAVI outcomes were comparable between the patients with or without chronic liver disease, except for a lower rate of pacemaker implantation in the patients with chronic liver disease (OR, 0.49[0.27-0.87], P = .02). In the patients with chronic liver disease, compared to SAVR, TAVI led to a decrease in the in-hospital mortality (OR, 0.43[0.22-0.86], P = .02) and need for transfusion (OR, 0.39[0.25-0.62], P < .0001). The rest outcomes were similar between the 2 groups.

CONCLUSIONS

This systematic review and meta-analysis supported that TAVI is a reliable therapeutic option for treating severe aortic stenosis in the patients with chronic liver disease. Future large-scale randomized controlled trials investigating the mid-term and long-term prognosis are needed to further verify these results.

Mortality after transcatheter versus surgical aortic valve replacement: an updated meta-analysis of randomised trials

Background

To determine whether transcatheter aortic valve implantation (TAVI) improves early (30-day) and midterm (1-year) mortality compared with surgical aortic valve replacement (SAVR), we performed an updated meta-analysis of all the currently available randomised controlled trials (RCTs).

Methods

To identify all RCTs providing both 30-day and 1‑year mortality after TAVI versus SAVR, PubMed and ClinicalTrials.gov were searched up to and including July 2019. A risk difference (RD) and its 95% confidence interval were generated using data of prespecified outcomes in both the TAVI and SAVR groups. Study-specific estimates were pooled using inverse variance-weighted averages of RDs in the random-effects model.

Results

We identified seven eligible high-quality RCTs including a total of 7631 as-treated patients. Pooled analyses demonstrated significantly lower 30-day (RD −0.60%; p = 0.046) and 1‑year all-cause mortality (RD −1.12%; p = 0.03) after TAVI than after SAVR. No funnel plot asymmetry was detected for 30-day and 1‑year mortality. Meta-regression analyses indicated that RDs of 30-day and 1‑year mortality between TAVI and SAVR were not modulated by mean Society of Thoracic Surgeons Predicted Risk of Mortality score. Bleeding complications at 30 days and 1 year and stage 2/3 acute kidney injury at 30 days were significantly less frequent after TAVI than after SAVR, whereas major vascular complications and new permanent pacemaker implantation at 30 days and 1 year were significantly more frequent after TAVI than after SAVR.

Conclusion

The best evidence from the present meta-analysis of all the currently available RCTs suggests that TAVI may reduce 30-day and 1‑year all-cause mortality compared with SAVR.

Electronic supplementary material

The online version of this article (10.1007/s12471-020-01378-1) contains supplementary material, which is available to authorized users.

Meta-Analysis Comparing Transcatheter Aortic Valve Implantation to Surgical Aortic Valve Replacement in Low Surgical Risk Patients

Transcatheter aortic valve implantation (TAVI) is recommended for inoperable and high risk surgical patients with severe aortic stenosis. It is noninferior to surgical aortic valve replacement (SAVR) in intermediate risk candidates. TAVI is currently being assessed for low surgical risk individuals. We performed a meta-analysis of randomized controlled trials (RCTs) and matched observational studies between TAVI and SAVR in low surgical risk patients. The primary outcomes were short-term and mid-term mortality and neurologic events. Secondary outcomes were other periprocedure complications. A total of 8 studies (3 RCTs and 5 matched observational studies) totaling 6,686 patients were included. No difference was seen in short-term mortality and neurologic events (risk ratio [RR] 0.68, 95% confidence interval [CI] 0.45 to 1.03, p 0.07 and RR 0.76, 95% CI 0.52 to 1.13, p 0.18) as well as mid-term mortality and neurologic events (RR 0.89, 95% CI 0.54 to 1.47, p 0.65 and RR 1.04, 95% CI 0.55 to 1.97, p 0.9) between the 2 groups. Reduced risk of new onset atrial fibrillation (RR 0.14, 95% CI 0.08 to 0.25, p <0.00001), acute kidney injury (RR 0.43, 95 CI 0.23 to 0.82, p 0.01), and bleeding (RR 0.43, 95% CI 0.27 to 0.69, p 0.0005) whereas increased risk of ≥ moderate aortic regurgitation (RR 6.53, 95% CI 3.48 to 12.24, p <0.00001), pacemaker or defibrillator implantation (RR 3.11, 95% CI 1.96 to 4.94, p <0.00001) and vascular complications (RR 5.29, 95% CI 1.58 to 17.70, p 0.007) was noted in TAVI arm. In conclusion, TAVI is comparable to SAVR in terms of short-term and mid-term mortality and neurologic events in low surgical risk patients. The risk of periprocedure events is variable.

Comparison of Outcomes of Transcatheter Versus Surgical Aortic Valve Replacement in Patients ≥80 Years of Age

Transcatheter aortic valve implantation (TAVI) procedures have increased exponentially since FDA approval in 2011. Older patients who underwent aortic valve replacement, either TAVI or surgical aortic valve replacement (SAVR), have elevated risk. Using the National Readmission Database, we included patients ≥80 years who underwent either TAVI or SAVR from 2011 to 2015. In-hospital outcomes of TAVI versus SAVR were compared using propensity-matched analysis to reduce the confounding effect of between-group imbalances. We identified a total of 30,590 TAVI and 54,204 SAVR procedures performed during the study period. The propensity score-matching algorithm yielded 19,713 patients in each group. The in-hospital mortality rates were significantly lower in TAVI compared with SAVR (3.4% vs 6.8%, p <0.001). Similarly, the 30-day readmission rate (15.2% vs 18.1% p = 0.001), in-hospital complications, mean length of stay (7 vs 12 days, p <0.001), and hospital cost (US$ 60,534 vs US$ 67,426) were significantly lower for TAVI patients. There was a significant increase in the use of TAVI (26 cased per month in 2011 to 1,237/month in 2015) and a decrease in SAVR (1,409/month in 2011 to 859/month in 2015) during the study period. In-patient mortality significantly decreased for patients who underwent TAVI (4.4% in 2011 to 2.5% in 2015) and did not significantly change for patients who underwent SAVR (5.0% in 2011 to 4.7% in 2015). Overall, the number of SAVR procedures remained two thirds higher than TAVI. In conclusion, in octo- and nonagenarians, TAVI is an effective and safer alternative to SAVR as it is associated with lower in-hospital mortality, lower major in-hospital complications, lower 30-day readmission rate, and hospital costs. Despite this, SAVR remained the most common approach in octogenarians, although the trends in this data set, suggest a shift in practice patterns for this cohort.

The state of transcatheter aortic valve implantation training in Canadian cardiac surgery residency programs

BACKGROUND

The current state of transcatheter aortic valve implantation (TAVI) training for Canadian cardiac surgical residents is unknown. Our goals were to establish a national inventory of TAVI educational resources, elucidate the role of residents in TAVI programs, and determine the attitudes and perspectives of residents and program directors regarding the importance of TAVI technology and training.

METHODS

We sent Web-based surveys and reminders to all Canadian cardiac surgical residents and program directors between February and July 2017. We used descriptive analyses to summarize data in an aggregate and anonymous manner. We analyzed patterned responses to open-ended survey questions using thematic analysis.

RESULTS

Seventy-eight of 92 residents (85%) and 11 of 12 program directors (92%) completed the survey, with broad representation from across Canada. A minority of residents (14 [18%]) and program directors (4 [36%]) reported that TAVI training in their program was adequate. Only 3 program directors (27%) reported that their residents had access to TAVI simulation training. Although most residents (76 [97%]) and program directors (10 [91%]) agreed that TAVI was important to the trainee's future practice, about two-thirds (54 [69%] and 7 [64%], respectively) agreed that TAVI should be a focus of fellowship training. A perceived lack of interest from interventional cardiologists to teach surgical residents, competition from TAVI fellows and lack of formalized time during residency were identified as perceived barriers to TAVI training.

CONCLUSION

As Canadian surgical residency training moves toward a Competence by Design curriculum, there remains a pressing need to create uniform learning objectives and expectations in the TAVI curriculum.

Transcatheter, sutureless and conventional aortic-valve replacement: a network meta-analysis of 16,432 patients

Background

Minimally invasive surgical techniques pose alternatives to conventional surgery for the treatment of aortic stenosis (AS). We present a Bayesian network analysis comparing Valve Academic Research Consortium-2 clinical outcomes between transcatheter aortic valve implantation (TAVI), sutureless (SL-AVR) and conventional aortic valve replacement (CAVR).

Methods

Electronic searches of databases were conducted and seven two-arm randomized-controlled trials and 25 propensity-score-matched studies comparing clinical outcomes of TAVI, SL-AVR and CAVR for treatment of AS were identified. Bayesian Markov chain Monte Carlo modelling was used to analyze clinical outcomes.

Results

The analysis included 16,432 patients who underwent TAVI [7,056], SL-AVR [1,238] or CAVR [8,138]. Compared to CAVR, TAVI and SL-AVR were associated with reduced postoperative major bleeding of 59% (OR 0.41, 95% CI: 0.28-0.59) and 44% (OR 0.56, 95% CI: 0.30-0.99) respectively. TAVI had a 41% reduction in postoperative myocardial infarction (OR 0.59, 95% CI: 0.40-0.86) and SL-AVR had a 40% reduction in postoperative acute kidney injury (AKI) (OR 0.62, 95% CI: 0.42-0.86). Compared to TAVI, CAVR and SL-AVR had a reduction in moderate/severe paravalvular regurgitation of 89% (OR 0.11, 95% CI: 0.07-0.16) and 92% (OR 0.08, 95% CI: 0.03-0.17). CAVR had a 67% decreased postoperative permanent pacemaker (PPM) implantation compared to TAVI (OR 0.33, 95% CI: 0.24-0.45) and a 63% reduction compared to SL-AVR (OR 0.37, 95% CI: 0.22-0.61). There were no differences in 30-day mortality or postoperative stroke between the groups.

Conclusions

In selected patients, minimally invasive surgical interventions including TAVI and SL-AVR for severe AS are viable alternatives to conventional surgery. However, TAVI is associated with increased paravalvular regurgitation, whereas TAVI and SL-AVR are associated with increased conduction disturbances compared to CAVR.

Transcatheter mitral valve replacement for mitral regurgitation-A meta-analysis

OBJECTIVES

We performed a meta-analysis to determine the outcomes in patients undergoing transcatheter mitral valve replacement (TMVR) for mitral regurgitation (MR).

METHODS

Databases including MEDLINE and EMBASE were searched through April 2018 using Web-based search engines (PubMed and OVID) to identify single-arm observational (case series) studies of TMVR enrolling ≥5 patients with MR. For each study, data regarding observed 30-day mortality and predicted operative mortality (Society of Thoracic Surgeons Predicted Risk of Mortality) were used to generate risk ratios (RRs) and 95% confidence intervals (CIs). Study-specific estimates were combined using the inverse variance-weighted average of logarithmic RRs in the random-effects model. One-group meta-analyses of 30-day and >30-day (including 30-day) mortality were also performed in the random-effects model.

RESULTS

Of 222 potentially relevant articles screened initially, nine eligible studies enrolling a total of 146 patients with MR undergoing TMVR were identified. In all but two studies, STS-PROM was available and varied from 3.3% to 15.4% (arithmetic mean, 7.6%). Pooled analyses demonstrated 30-day mortality of 20.4% (95%CI, 9.6-31.2%), >30-day mortality of 32.0% (95%CI, 19.8-44.2%), and non-significantly higher observed 30-day mortality than predicted operative mortality (RR, 1.70; 95%CI, 0.85-3.42; P = 0.14). There was no evidence of significant publication bias.

CONCLUSION

TMVR for patients with MR results in increased early and late mortality.

Systematic review and meta-analysis in cardiac surgery: a primer

PURPOSE OF REVIEW

The purpose of this article is to review the strengths and weaknesses of systematic reviews and meta-analyses to inform our current understanding of cardiac surgery.

RECENT FINDINGS

A systematic review and meta-analysis of a focused topic can provide a quantitative estimate for the effect of a treatment intervention or exposure. In cardiac surgery, observational studies and small, single-center prospective trials provide most of the clinical outcomes that form the evidence base for patient management and guideline recommendations. As such, meta-analyses can be particularly valuable in synthesizing the literature for a particular focused surgical question. Since the year 2000, there are over 800 meta-analysis-related publications in our field. There are some limitations to this technique, including clinical, methodological and statistical heterogeneity, among other challenges. Despite these caveats, results of meta-analyses have been useful in forming treatment recommendations or in providing guidance in the design of future clinical trials.

SUMMARY

There is a growing number of meta-analyses in the field of cardiac surgery. Knowledge translation via meta-analyses will continue to guide and inform cardiac surgical practice and our practice guidelines.

Transcatheter versus surgical aortic valve replacement in patients at low surgical risk: A meta-analysis of randomized trials and propensity score matched observational studies

BACKGROUND

Although transcatheter aortic valve replacement (TAVR) is officially indicated for high risk aortic stenosis (AS) patients, the procedure is increasingly being performed in patients who are not at high surgical risk, including a substantial number of low risk patients. However, data on the benefit of TAVR in this patient population is limited.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies with propensity score matching (PSM) of TAVR versus surgical aortic valve replacement (SAVR) in patients who are at low surgical risk. The primary outcome was all-cause mortality. The secondary outcomes included stroke, myocardial infarction, bleeding, and various procedural complications.

RESULTS

Six studies (2 RCTs and 4 PSM studies) totaling 3,484 patients were included. Follow-up ranged from 3 months to 3 years (median 2 years). The short-term mortality was similar with either TAVR or SAVR (2.2% for TAVR and 2.6% for SAVR, RR 0.89, 95% CI 0.56-1.41, P = 0.62), however, TAVR was associated with increased risk for intermediate-term mortality (17.2% for TAVR and 12.7% for SAVR, RR 1.45, 95% CI 1.11-1.89, P = 0.006). In terms of periprocedural complications, TAVR was associated with reduced risk for bleeding and renal failure and an increase in vascular complications and Pacemaker implantation.

CONCLUSIONS

In patients who are at low surgical risk, TAVR seems to be associated with increased mortality risk. Until more data in this population is available, SAVR should remain the treatment of choice for these patients.

Variations in rotation of the aortic root and membranous septum with implications for transcatheter valve implantation

Objective

It is intuitive to suggest that knowledge of the variation in the anatomy of the aortic root may influence the outcomes of transcatheter implantation of the aortic valve (TAVI). We have now assessed such variation.

Methods

We used 26 specimens of normal hearts and 78 CT data sets of adults with a mean age of 64±15 years to measure the dimensions of the membranous septum and to assess any influence played by rotation of the aortic root, inferring the relationship to the atrioventricular conduction axis.

Results

The aortic root was positioned centrally in the majority of both cohorts, although with significant variability. For the cadaveric hearts, 14 roots were central (54%), 4 clockwise-rotated (15%) and 8 counterclockwise-rotated (31%). In the adult CT cohort, 44 were central (56%), 21 clockwise-rotated (27%) and 13 counterclockwise-rotated (17%). A mean angle of 15.5° was measured relative to the right fibrous trigone in the adult CT cohort, with a range of −32° to 44.7°. The dimensions of the membranous septum were independent of rotation. Fibrous continuity between the membranous septum and the right fibrous trigone increased with counterclockwise to clockwise rotation, implying variation in the relationship to the atrioventricular conduction axis.

Conclusions

The central fibrous body is wider, providing greater fibrous support, in the setting of clockwise rotation of the aortic root. Individuals with this pattern may be more vulnerable to conduction damage following TAVI. Knowledge of such variation may prove invaluable for risk stratification.