Long-term survival after transcatheter versus surgical aortic valve replacement for aortic stenosis: A meta-analysis of observational comparative studies with a propensity-score analysis

Comparison of transcatheter and surgical aortic valve replacement long-term outcomes: a retrospective cohort study with overlap propensity score weighting

BACKGROUND AND AIMS

Randomised controlled trials comparing transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) were performed in highly selected populations and data regarding long-term secondary complications beyond mortality are scarce. This study used data from Ontario, Canada to compare mid-term and long-term clinical outcomes in a representative real-world cohort of patients who underwent TAVR and SAVR from 2007 to 2016.

METHODS

A novel overlap weighting propensity score method was used to match patients undergoing TAVR or SAVR. Primary outcomes were all-cause, cardiovascular and non-cardiovascular mortality either in-hospital or at 1, 3 and 5 years postdischarge. Secondary outcomes included adverse outcomes and readmission. Long-term primary and secondary outcomes were compared using a weighted competing risks subdistribution proportional hazards model.

RESULTS

The study included 9355 SAVR and 2641 TAVR patients. All-cause mortality at 1 year (HR 1.21; 95% CI 1.02 to 1.43), 3 years (HR 1.45; 95% CI 1.28 to 1.64) and 5 years (HR 1.48; 95% CI 1.33 to 1.65) was significantly higher among patients underwent TAVR compared with SAVR, with both cardiovascular mortality at 3 and 5 years and non-cardiovascular mortality at 1, 3 and 5 years significantly higher for TAVR. Hazards of myocardial infarction and readmission for angina at 1, 3 and 5 years were significantly greater for TAVR.

CONCLUSIONS

In this overlap weighted cohort, both cardiac and non-cardiac mortality rates were increased in TAVR patients. Residual or unmeasured confounding may have contributed to these findings. More studies are needed to identify factors predictive of long-term outcomes in real-world cohorts.

Network Meta-Analysis Comparing Transcatheter, Minimally Invasive, and Conventional Surgical Aortic Valve Replacement

The landscape of aortic valve replacement (AVR) has evolved dramatically over the years, but time-varying outcomes have yet to be comprehensively explored. This study aimed to compare the all-cause mortality among 3 AVR techniques: transcatheter (TAVI), minimally invasive (MIAVR), and conventional AVR (CAVR). An electronic literature search was performed for randomized controlled trials (RCTs) comparing TAVI with CAVR and RCTs or propensity score-matched (PSM) studies comparing MIAVR with CAVR or MIAVR to TAVI. Individual patient data for all-cause mortality were derived from graphical reconstruction of Kaplan-Meier curves. Pairwise comparisons and network meta-analysis were conducted. Sensitivity analyses were performed in the TAVI arm for high risk and low/intermediate risk, as well as patients who underwent transfemoral (TF) TAVI. A total of 27 studies with 16,554 patients were included. In the pairwise comparisons, TAVI showed superior mortality to CAVR until 37.5 months, beyond which there was no significant difference. When restricted to TF TAVI versus CAVR, a consistent mortality benefit favoring TF TAVI was seen (shared frailty hazard ratio [HR] = 0.86, 95% confidence interval [CI] = 0.76 to 0.98, p = 0.024). In the network meta-analysis involving majority PSM data, MIAVR demonstrated significantly lower mortality than TAVI (HR = 0.70, 95% CI = 0.59 to 0.82) and CAVR (HR = 0.69, 95% CI = 0.59 to 0.80); this association remained compared with TF TAVI but with a lower extent of benefit (HR = 0.80, 95% CI = 0.65 to 0.99). In conclusion, the initial short- to medium-term mortality benefit for TAVI over CAVR was attenuated over the longer term. In the subset of patients who underwent TF TAVI, a consistent benefit was found. Among majority PSM data, MIAVR showed improved mortality compared with TAVI and CAVR but less than the TF TAVI subset, which requires validation by robust RCTs.

Trend in morbidity and mortality in surgical aortic valve replacement: a retrospective, observational, single-centre study

OBJECTIVES

Continuous improvement in the management of patients undergoing surgical aortic valve replacement (SAVR) may have considerably enhanced surgical outcomes including in-hospital mortality and perioperative complications. We aimed to analyse in-hospital mortality and morbidity trends in patients undergoing SAVR in a single centre to provide insights for future benchmarking for transcatheter aortic valve implantation indications.

METHODS

This was a retrospective study of prospectively collected data from patients undergoing either isolated SAVR or combined with coronary artery bypass grafting (CABG) at the Bristol Heart Institute, UK, from January 2000 to December 2017. Baseline characteristics were extracted and analysed across 3 different eras (2000-2005, 2006-2011 and 2012-2017). Risk-adjusted time trend was obtained from univariate and multivariate logistic regression including all baseline characteristics.

RESULTS

A total of 2719 patients (63.2%) underwent isolated SAVR, and 1581 (36.8%) underwent combined CABG and SAVR during the study period. For patients undergoing SAVR, in-hospital mortality decreased from 2.9% in 2000-2005 to 0.7% in 2012-2017 (risk-adjusted time trend 0.0001). Hospital mortality in patients aged 75-79 and ≥80 years decreased from 5.6% and 5.3% to 0.4% and 2.2%, respectively. Mortality after combined SAVR and CABG did not significantly decrease (from 3.9% in 2000-2005 to 3.5% in 2012-2017; risk-adjusted time trend = 0.62). However, in patients aged ≥80 years, index hospitalization mortality showed a decreasing non-significant trend from 9.8% to 4.8%.

CONCLUSIONS

Our findings support the hypothesis that mortality and morbidity rates following SAVR have significantly improved over the years, including for patients at high risk.

Transcatheter aortic valve implantation versus surgical aortic valve replacement for treatment of severe aortic stenosis: comparison of results from randomized controlled trials and real-world data

Objective

Results from randomized controlled trials (RCTs) and real-world study (RWS) appear to be discordant. We aimed to investigate whether data derived from RCTs and RWS evaluating long-term all-cause mortality of transcatheter aortic valve implantation (TAVI) versus surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis (AS) were in agreement.

Methods

RCTs or RWS comparing TAVI and SAVR, reporting longterm (≥2-year follow-up) all-cause mortality, were identified. We also carried out subgroup analyses to access the effect in different subgroups. A pre-designated data extraction form including 5 domains and 26 items was used to explore the relationship between RCTs and RWS. Mortality and effect in different subgroups were evaluated using random-effects meta-analyses.

Results

Five RCTs (5421 participants, TAVI: 2759, SAVR: 2662) and 33 RWS (20839 participants; TAVI: 6585, SAVR: 14254) were identified. Pooled RCT analysis showed no difference in all-cause mortality between TAVI and SAVR (HR=0.97, 95% CI: 0.88-1.07; P=0.55). In RWS, TAVI was associated with an increased risk of allcause mortality (HR=1.46, 95% CI: 1.26-1.69; P<0.001) compared to SAVR.

Conclusion

These results highlight the inconsistencies between RCTs and RWS in assessing long-term all-cause mortality in the treatment of AS using TAVI or SAVR, which may be caused by interactions of clinical characteristics or study design. RCTs as well as RWS are both developing and improving; the advantages of one kind of design, measurement and evaluation can and should be thoughtfully referred to the other.

A meta-analysis of ≥5-year mortality after transcatheter versus surgical aortic valve replacement

INTRODUCTION

It remains unclear whether long-term survival is superior following transcatheter aortic valve implantation (TAVI) than following surgical aortic valve replacement (SAVR). We performed a meta-analysis of mortality with ≥5-year follow-up in randomized controlled trials (RCTs) and propensity-score matched (PSM) studies of TAVI versus SAVR.

EVIDENCE ACQUISITION

MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched through March 2019. Eligible studies were RCTs or PSM studies of TAVI versus SAVR enrolling patients with severe aortic stenosis and reporting all-cause mortality with ≥5-year follow-up as an outcome. A hazard ratio of mortality for TAVI versus SAVR was extracted from each individual study.

EVIDENCE SYNTHESIS

Our search identified 3 RCTs and 7 PSM studies enrolling 5498 patients. A pooled analysis of all 10 studies demonstrated a statistically significant 38% increase in mortality with TAVI relative to SAVR. A subgroup meta-analysis showed no statistically significant difference between TAVI and AVR in RCTs and a statistically significant 68% increase with TAVI relative to SAVR in PSM studies.

CONCLUSIONS

On the basis of a meta-analysis of 7 PSM studies, TAVI is associated with greater all-cause mortality with ≥5-year follow-up than SAVR. However, another meta-analysis of 3 RCTs suggests no difference in mortality between TAVI and SAVR.

Preoperative Anemia and Postoperative Mortality in Patients with Aortic Stenosis Treated with Transcatheter Aortic Valve Implantation (TAVI): A Systematic Review and Meta-Analysis

BACKGROUND Patients with severe aortic stenosis who have comorbidities that prevent general anesthesia and open cardiothoracic surgery are candidates for transcatheter aortic valve implantation (TAVI). However, TAVI can result in patient mortality following the procedure. This systematic review of the literature and meta-analysis aimed to determine the relationship between preoperative anemia and postoperative mortality in patients following TAVI. MATERIAL AND METHODS PubMed, EMBASE, the Cochrane Library, and the Web of Science were systematically searched from their inception to February 2019 for relevant published studies that included patients with bicuspid aortic valve stenosis and tricuspid aortic valve stenosis who underwent TAVI and who had preoperative data on hemoglobin levels. The pooled odds ratios (OR) and 95% confidence interval (CI) were calculated using a random-effects generic inverse variance method. RESULTS Six published studies that involved 6,406 patients with aortic stenosis were included in the meta-analysis. There was no significant difference observed for the final pooled result for patients with and without anemia for the short-term 30-day postoperative mortality (OR, 1.34; 95% CI, 0.77-2.35). However, long-term mortality rates were significantly worse in patients with preoperative anemia compared with those without anemia (OR, 1.77; 95% CI, 1.34-2.35). CONCLUSIONS Systematic review of the literature and meta-analysis showed that pre-procedural anemia reduced long-term mortality following TAVI. This finding supports the need to correct preoperative anemia in patients with aortic stenosis to improve patient outcome following TAVI.