Transcatheter Versus Surgical Aortic Valve Replacement in Patients With Lower Surgical Risk Scores: A Systematic Review and Meta-Analysis of Early Outcomes

Modern Cardiac Surgical Outcomes in Nonagenarians: A Multicentre Retrospective Observational Study

Background

There have been multiple recent advancements in the selection, optimisation and management of patients undergoing cardiac surgery. However, there is limited data regarding the outcomes in nonagenarians, despite this cohort being increasingly referred for these interventions. The objective of this study was to describe the patient characteristics, management and outcomes of a cohort of nonagenarians undergoing cardiac surgery receiving contemporary peri-operative care.

Methods

After receiving ethics approval, we conducted a retrospective observational study of nonagenarians who had undergone cardiac surgery requiring a classic median sternotomy. All operative indications were included. We excluded patients who underwent transcatheter aortic valve implantation (TAVI), and surgery on the thoracic aorta via an endovascular approach (TEVAR). Patients undergoing TEVAR often have the procedure done under sedation and regional blocks with local anesthetic solution. There is no open incision and these patients do not require cardiopulmonary bypass. We also excluded patients undergoing minimally invasive mitral valve surgery via a videoscope assisted approach. These patients do not have a median sternotomy, have the procedure done via erector spinae block, and often are extubated on table. Data were collected from four hospitals in Victoria, Australia, over an 8-year period (January 2012–December 2019). The primary objective was to assess 6-month mortality in nonagenarian patients undergoing cardiac surgery and to provide a detailed overview of postoperative complications. We hypothesized that cardiac surgery in nonagenarian patients would be associated with a 6-month postoperative mortality <10%. As a secondary outcome, we hypothesized that significant postoperative complications (i.e., Clavien Dindo Grade IIIb or greater) would occur in > 30% of patients.

Results

A total of 12,358 adult cardiac surgery patients underwent surgery during the study period, of whom 18 nonagenarians (0.15%) fulfilled inclusion criteria. The median (IQR) [min-max] age was 91.0 years (90.0:91.8) [90–94] and the median body mass index was 25.0 (kg/m²) (22.3:27.0). Comorbidities, polypharmacy, and frailty were common. The median predicted mortality as per EuroSCORE-II was 6.1% (4.1:14.5). There were no cases of intra-operative, in-hospital, or 6-month mortality. One (5.6%) patient experienced two Grade IIIa complications. Three (16.7%) patients experienced Grade IIIb complications. Three (16.7%) patients had an unplanned hospital readmission within 30 days of discharge. The median value for postoperative length of stay was 11.6 days (9.8:17.6). One patient was discharged home and all others were discharged to an inpatient rehabilitation facility.

Conclusion

In this selected, contemporary cohort of nonagenarian patients undergoing cardiac surgery, postoperative 6-month mortality was zero. These findings support carefully selected nonagenarian patients being offered cardiac surgery (Trials Registry: https://www.anzctr.org.au/ACTRN12622000058774.aspx).

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.

Transcatheter aortic valve implantation in low-risk patients: is it too early?

The median age of patients treated by transcatheter aortic valve implantation (TAVI) is falling across Europe, and low-risk patients with severe aortic stenosis (AS) represent 80% of patients with severe AS undergoing surgical aortic valve replacement (SAVR). There are few data for TAVI in low-risk patients, but there are four ongoing randomised trials of SAVR versus TAVI. The key issues relate to pacemaker implantation rates and the associated potential longer term deleterious effects, and the need to minimise vascular complications and paravalvular leak. Valve leaflet thrombosis and paucity of data on valve durability remain a concern. Given the higher incidence of bicuspid aortic valves in younger patients, outcomes of TAVI in this setting need clarification and are discussed.

Comparing Transcatheter Aortic Valve Replacement (AVR) With Surgical AVR in Lower Risk Patients: A Comprehensive Meta-Analysis and Systematic Review

Background

Transcutaneous aortic valve replacement (TAVR) is a novel percutaneous procedure for severe aortic stenosis and has been recently approved by Food and Drug Administration in lower risk patients. We performed the first ever meta-analysis and literature review of clinical trials comparing both 30-day and 1-year outcomes in lower risk patients undergoing TAVR vs. surgical aortic valve replacement (SAVR, having Society of Thoracic Surgeons score < 4% or equivalent).

Methods

Using predefined selection criteria as above, 68 articles were identified. Seven eligible articles were selected after extensive review. Primary effect outcomes were 30-day and 1-year all-cause mortality using risk ratio (RR) with significant P value of < 0.05.

Results

A total of 4,859 subjects were included. Risk of 30-day all-cause mortality was 40.1% less in TAVR group, RR 0.59 (95% confidence interval (CI): 0.38 - 0.92, P = 0.02) with no significant heterogeneity. Six studies except Schymik et al also reported 1-year risk. This was, however, not statistically significant with a 21% decrease in the TAVR group, RR 0.79 (95% CI: 0.57 - 1.09, P = 0.15). Six studies reported 30-day risk of secondary outcomes. The risk of 30-day stroke was 36% less in TAVR group, although this was not statistically significant, RR 0.64 (95% CI: 0.38 - 1.9, P = 0.10). The risk of acute kidney injury (AKI) stage 2 and above was 56% less in post-TAVR patients, RR 0.43 (95% CI: 0.35 - 0.54, P < 0.001) with no heterogeneity. For vascular complications, RR was high in TAVR group 4.62 (95% CI: 1.42-15.18, P = 0.01). Significant heterogeneity was demonstrated though (I² = 81). The risks for permanent pacemaker (PPM) were also higher in the TAVR group, RR 3.30 (95% CI: 2.04 - 5.33, P < 0.001) and significant heterogeneity was observed. After removing Thyregod et al and Partner 3 trial from the analysis, heterogeneity was removed, but the RR was still high 3.21 (95% CI: 2.54 - 4.068, P < 0.001). Post-operative incidence of endocarditis among TAVR patients was low but not statistically significant. The 30-day risk for infective endocarditis was RR 0.67 (95% CI: 0.13 - 3.48, P = 0.63). The 1-year risk was similarly low but not significant, RR 0.73 (95% CI: 0.28 - 1.92, P = 0.53).

Conclusions

Among low risk patients, TAVR was found to be superior in short-term all-cause mortality and 1-year stroke, a result that was statistically significant for TAVR and close to significance for stroke. TAVR patients were also less likely to have post-operative bleeding and AKI stage 2 and beyond. Post-operative incidence of endocarditis among TAVR patients was low but not statistically significant. However, the rates of PPM and vascular complications are higher in TAVR patients. The results of TAVR in low risk population are thus extremely encouraging. However, the issue of long-term valve durability in this group needs further studies. Also, caution needs to be exercised while extending the indications to extremely young patients due to lack of enough studies.

Current issues in transcatheter aortic valve replacement

Aortic stenosis is the most common valvular disease worldwide. With transcatheter aortic valve replacement (TAVR) being increasingly expanded to lower-risk populations, several challenging issues remain to be solved. The present review aims at discussing modern approaches to such issues as well as the current status of TAVR. TAVR has undergone several developments in the recent years: an increased use of transfemoral access, the development of prostheses in order to adapt to challenging anatomies, improved delivery systems with repositioning features, and outer skirts aiming at reducing paravalvular leak. The indication of TAVR is increasingly being expanded to patients with lower surgical risk. The main clinical trials supporting such expansion are reviewed and the latest data on low-risk patients are discussed. A number of challenges need still to be addressed and are also reviewed in this paper: the need for updated international guidelines including the latest evidence; a reduction of main complications such as permanent pacemaker implantation, paravalvular leak, and stroke (and its potential prevention by using anti-embolic protection devices); the appropriate role of TAVR in patients with concomitant cardiac ischemic disease; and durability of bio-prosthetic implanted valves. Finally, the future perspectives for TAVR use and next device developments are discussed.

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.

Transcatheter aortic valve implantation versus surgical aortic valve replacement for severe aortic stenosis in people with low surgical risk

BACKGROUND

Severe aortic valve stenosis (AS) is a major cause of morbidity and mortality worldwide. The definitive management for severe AS is aortic valve replacement (AVR). The choice of transcatheter approach versus open-heart surgery for AVR in people with severe AS and low surgical risk remains a matter of debate.

OBJECTIVES

To assess the benefits and harms of transcatheter aortic valve implantation (TAVI) compared to surgical aortic valve replacement (SAVR) in people with severe AS and low surgical risk.

SEARCH METHODS

We searched the following databases for randomised controlled trials (RCTs) on 29 April 2019: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and Web of Science Core Collection. We also searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform. We searched all databases from inception to present and imposed no restriction on language or date of publication.

SELECTION CRITERIA

We included RCTs that compared TAVI and SAVR in adults (18 years of age or older) with severe AS and low surgical risk.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. Two authors independently screened titles and abstracts for inclusion, performed data extraction, and assessed risk of bias in the studies included. We analysed dichotomous data using the risk ratio (RR) and continuous data using the mean difference (MD), with respective 95% confidence intervals (CI). We assessed the certainty of evidence for each outcome using the GRADE approach. Our outcomes of interest were assessed in the short term (i.e. during hospitalisation and up to 30 days of follow-up). Primary outcomes were all-cause mortality, stroke, and rehospitalisation. Secondary outcomes were myocardial infarction (MI), cardiac death, length of hospital stay (LOS), permanent pacemaker (PPM) implantation, new-onset atrial fibrillation, acute kidney injury (AKI), and any bleeding.

MAIN RESULTS

We identified four studies (13 reports), with 2818 participants, and one ongoing study. Overall certainty of evidence ranged from high to very low. There is probably little or no difference between TAVI and SAVR for the following short-term outcomes: all-cause mortality (RR 0.69, 95% CI 0.33 to 1.44; SAVR 11 deaths per 1000, TAVI 8 deaths per 1000 (95% CI 4 to 16); 2818 participants; 4 studies; moderate-certainty evidence); stroke (RR 0.73, 95% CI 0.42 to 1.25; SAVR 21 strokes per 1000, TAVI 16 strokes per 1000 (95% CI 9 to 27); 2818 participants; 4 studies; moderate-certainty evidence); MI (RR 0.82, 95% CI 0.42 to 1.58; SAVR 14 MI per 1000, TAVI 11 MI per 1000 (95% CI 6 to 21); 2748 participants; 3 studies; moderate-certainty evidence); and cardiac death (RR 0.71, 95% CI 0.32 to 1.56; SAVR 10 cardiac deaths per 1000, TAVI 7 cardiac deaths per 1000 (95% CI 3 to 16); 2818 participants; 4 studies; moderate-certainty evidence). TAVI may reduce the risk of short-term rehospitalisation, although the confidence interval also includes the possibility of no difference in risk between groups (RR 0.64, 95% CI 0.39 to 1.06; SAVR 30 cases per 1000, TAVI 19 cases per 1000 (95% CI 12 to 32); 2468 participants; 2 studies; low-certainty evidence). TAVI, compared with SAVR, probably increases the risk of PPM implantation (RR 3.65, 95% CI 1.50 to 8.87; SAVR 47 per 1000, TAVI 170 cases per 1000 (95% CI 70 to 413); number needed to treat for an additional harmful outcome (NNTH) = 7; 2683 participants; 3 studies; moderate-certainty evidence). We are uncertain whether TAVI, compared with SAVR, affects the LOS in days, although it appears to be associated with shorter LOS. TAVI, compared with SAVR, reduces the risk of atrial fibrillation (RR 0.21, 95% CI 0.15 to 0.30; 2683 participants; 3 studies), AKI (RR 0.30, 95% CI 0.16 to 0.58; 2753 participants; 4 studies), and bleeding (RR 0.31, 95% CI 0.16 to 0.62; 2753 participants; 4 studies) (all high-certainty evidence).

AUTHORS' CONCLUSIONS

Our meta-analysis indicates that, in the short term, TAVI probably has little or no mortality difference compared to SAVR for severe AS in individuals with low surgical risk. Similarly, there is probably little or no difference in risk of stroke, MI, and cardiac death between the two approaches. TAVI may reduce the risk of rehospitalisation, but we are uncertain about the effects on LOS. TAVI reduces the risk of atrial fibrillation, AKI, and bleeding. However, this benefit is offset by the increased risk of PPM implantation. Long-term follow-up data are needed to further assess and validate these outcomes, especially durability, in the low surgical risk population.

Echocardiographic outcomes from seven randomized trials of transcatheter versus surgical aortic valve replacement

AIMS

We performed meta-analyses of echocardiographic outcomes, including postprocedural aortic valve area (AVA), aortic valve mean pressure gradient (MPG), and paravalvular aortic regurgitation (PAR), exclusively from all currently available randomized controlled trials (RCTs) of transcatheter aortic valve implantation (TAVI) versus surgical aortic valve replacement (SAVR).

METHODS

To identify all RCTs providing echocardiographic outcomes (AVA, MPG, and PAR) up to 2 years after TAVI versus SAVR, PubMed and ClinicalTrials.gov were searched through June 2019. Mean differences in AVA (and MPG) between the TAVI and SAVR groups and odds (or hazard) ratios of at least moderate PAR for TAVI versus SAVR were pooled using the random-effects meta-analysis.

RESULTS

We identified seven eligible RCTs. At 30 days (P = 0.004), 1 year (P = 0.006), and 2 years (P = 0.03), AVA was significantly larger after TAVI than after SAVR. After TAVI than after SAVR, MPG was significantly lower at 30 days (P = 0.03) and 2 years (P = 0.01), and nonsignificantly lower at 1 year (P = 0.06). At 30 days (P < 0.00001), 1 year (P < 0.00001), and 2 years (P < 0.00001), incidence of at least moderate PAR was significantly greater after TAVI than after SAVR.

CONCLUSION

On the basis of the present meta-analyses of all the seven currently available RCTs, AVA is larger, MPG is lower, and incidence of at least moderate PAR is greater 30 days, 1 and 2 years after TAVI than after SAVR.

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.

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.

Length of Stay and Discharge Disposition After Transcatheter Versus Surgical Aortic Valve Replacement in the United States

BACKGROUND

As transcatheter aortic valve replacement (TAVR) extends its reach to lower surgical risk patients, the differences between resource utilization for TAVR and surgical AVR (SAVR) will become increasingly important.

METHODS AND RESULTS

AVR procedures between January 2012 and September 2015 at hospitals performing TAVR were identified using the National Inpatient Sample databases. Adults aged ≥50 years with aortic stenosis who underwent isolated TAVR or SAVR were eligible for inclusion. Standardized morbidity ratio weights were calculated using patient demographics, comorbidities, and hospital characteristics. Weighted linear and generalized logistic regression models were used to estimate the effect of undergoing TAVR, compared with undergoing SAVR, on length of stay (LOS) and discharge disposition. In TAVR-performing hospitals, 7266 (40%) patients underwent TAVR (6107 endovascular approach and 1159 transapical approach), while 10 833 (60%) underwent isolated SAVR. Patients undergoing TAVR were older, more likely to be female, and had more comorbidities. From 2012 to 2015, average LOS declined for both TAVR (6.3 days to 4.6 days; P<0.0001) and SAVR (7.5 days to 6.8 days; P<0.0001), with greater reduction in the TAVR group ( P<0.0001). An increase in home/home health discharge was noted with TAVR (67.7%-77.4%; P<0.0001) but not with SAVR (76.8%-79.5%; P=0.25). After standardizing, patients undergoing TAVR had significantly shorter LOS (change in estimate, -2.93, 95% CI, -3.26 to -2.60) and lower incidence of transfer to skilled nursing facility (odds ratio, 0.45; 95% CI, 0.40-0.51) but no difference in in-hospital mortality (odds ratio, 0.85; 95% CI, 0.61-1.20) compared with if they had undergone SAVR. As compared with SAVR, patients who had TAVR performed via an endovascular approach had shorter LOS and lower rates of skilled nursing facility transfer, whereas in the transapical cohort, LOS, and skilled nursing facility transfer were similar to SAVR.

CONCLUSIONS

As compared with if they undergo SAVR, patients undergoing TAVR (by a nontransapical approach) had a shorter LOS and higher likelihood of home discharge, as opposed to skilled nursing facility. From 2012 to 2015, there was a greater trend towards a reduction of LOS and more home discharges among TAVR, as opposed to SAVR. These data have important implications in the era of constrained resources with a growing emphasis on reducing health care costs.

Why should we extend transcatheter aortic valve implantation to low-risk patients? A comprehensive review

Within the past decade, transcatheter aortic valve implantation (TAVI) has become established as the optimal treatment option for elderly, inoperable and high-risk patients with severe aortic stenosis, and is now recommended by international guidelines. Randomized controlled trials have demonstrated the non-inferiority of TAVI to open surgery in intermediate-risk patients and, most recently, in low-risk patients. Further randomized controlled trials are underway, but existing studies have already provided reassuring data in this cohort, and TAVI is offered routinely to younger and lower-risk patients in numerous centers. Improvements in the design of devices and delivery systems, accompanied by increased operator experience, have dramatically improved the safety of the procedure, and further expansion into low-risk groups seems inevitable once concerns about valve durability and device cost have been addressed. In this article, we provide a review of the existing literature, and estimate the clinical impact of TAVI in low-risk patients. Abbreviated title: Why should we extend TAVI to low-risk patients?

Pre-procedural fit-testing of TAVR valves using parametric modeling and 3D printing

BACKGROUND

Successful transcatheter aortic valve replacement (TAVR) requires an understanding of how a prosthetic valve will interact with a patient's anatomy in advance of surgical deployment. To improve this understanding, we developed a benchtop workflow that allows for testing of physical interactions between prosthetic valves and patient-specific aortic root anatomy, including calcified leaflets, prior to actual prosthetic valve placement.

METHODS

This was a retrospective study of 30 patients who underwent TAVR at a single high volume center. By design, the dataset contained 15 patients with a successful annular seal (defined by an absence of paravalvular leaks) and 15 patients with a sub-optimal seal (presence of paravalvular leaks) on post-procedure transthoracic echocardiogram (TTE). Patients received either a balloon-expandable (Edwards Sapien or Sapien XT, n = 15), or a self-expanding (Medtronic CoreValve or Core Evolut, n = 14, St. Jude Portico, n = 1) valve. Pre-procedural computed tomography (CT) angiograms, parametric geometry modeling, and multi-material 3D printing were utilized to create flexible aortic root physical models, including displaceable calcified valve leaflets. A 3D printed adjustable sizing device was then positioned in the aortic root models and sequentially opened to larger valve sizes, progressively flattening the calcified leaflets against the aortic wall. Optimal valve size and fit were determined by visual inspection and quantitative pressure mapping of interactions between the sizer and models.

RESULTS

Benchtop-predicted "best fit" valve size showed a statistically significant correlation with gold standard CT measurements of the average annulus diameter (n = 30, p < 0.0001 Wilcoxon matched-pairs signed rank test). Adequateness of seal (presence or absence of paravalvular leak) was correctly predicted in 11/15 (73.3%) patients who received a balloon-expandable valve, and in 9/15 (60%) patients who received a self-expanding valve. Pressure testing provided a physical map of areas with an inadequate seal; these corresponded to areas of paravalvular leak documented by post-procedural transthoracic echocardiography.

CONCLUSION

We present and demonstrate the potential of a workflow for determining optimal prosthetic valve size that accounts for aortic annular dimensions as well as the active displacement of calcified valve leaflets during prosthetic valve deployment. The workflow's open source framework offers a platform for providing predictive insights into the design and testing of future prosthetic valves.

Transcatheter aortic valve replacement in low risk patients

Transcatheter aortic valve replacement (TAVR) is a relatively new technology that has grown exponentially over the past decade. Although it was initially restricted to elderly patients at very high or prohibitive surgical risk, it is currently being evaluated as a treatment option in younger and lower risk patients. The increasing experience of the Heart Teams, along with the continued refinement of transcatheter valve technology has resulted in TAVR achieving results comparable to those of surgery for treating intermediate-risk patients. Furthermore, promising preliminary results have been obtained from observational and propensity matched studies in low risk patients, and a small randomized trial showed the non-inferiority of TAVR vs. SAVR regarding early and late (up to 6 years) outcomes. Three ongoing randomized trials will provide the definite response about the safety and efficacy of TAVR for treating low risk patients with severe aortic stenosis in the near future. The (expected) positive results of these studies would establish the basis for TAVR as the preferred treatment for the majority of patients with aortic stenosis. However, continuous research efforts for better determining valve durability among TAVR recipients, as well as reducing some of the genuine and frequent complications of TAVR (e.g. conduction disturbances) are important in this final effort for making TAVR the default treatment for aortic stenosis.

Two-Year Outcomes of Transcatheter Compared With Surgical Aortic Valve Replacement in "Minimal-Risk" Patients Lacking EuroSCORE Co-morbidities (from the TAVIK Registry)

We aimed to compare the outcomes of transcatheter aortic valve implantation (TAVI) with surgical aortic valve replacement (SAVR) in an elderly but nonfrail, minimally co-morbid population. Although data comparing these 2 procedures in intermediate- and low-risk patients are mounting, no distinction has been made between co-morbidity and age/gender as driving forces for surgical risk. Patients undergoing isolated TAVI or SAVR between May 2008 and March 2015 were documented. Data for 225 patients (TAVI 132, SAVR 93) aged ≥75 and <86 years and fulfilling minimal-risk criteria were analyzed. Patients who underwent TAVI were older (80.7 vs 77.4 years, p <0.0001) and had a higher mean Society of Thoracic Surgeons score (2.16% vs 1.72%, p <0.0001). Mild prosthetic valve regurgitation (odds ratio [OR] 4.9, 95% confidence interval [CI] 3.34 to 7.20) was more likely after TAVI, as were renal complications (predominantly stage I acute kidney injury; OR 2.86, 95% CI 1.79 to 4.55) and new pacemaker implantation (OR 3.33, 95% CI 1.76 to 6.26) at 30 days; however, life-threatening bleeding (OR 0.58, 95% CI 0.36 to 0.93) and reintervention for bleeding (OR 0.03, 95% CI 0.01 to 0.13) were less likely. Survival was comparable between groups at 30 days (99.2% vs 100%, p = 1.0) and 1 year (96.2% vs 96.8%, OR 0.85, 95% CI 0.20 to 3.63, p = 0.823), but it was poorer for patients who underwent TAVI at 2 years (OR 0.31, 95% CI 0.16 to 0.61). In conclusion, the short-term outcomes of TAVI in elderly, low-risk, minimally co-morbid patients appear to be similar to those of SAVR, with access-specific complications. Although these results point toward the potential for more liberal use of TAVI in minimal-risk patients, poorer midterm survival remains a concern, requiring further exploration.

Comprehensive update on the new indications for transcatheter aortic valve replacement in the latest 2017 European guidelines for the management of valvular heart disease

New European guidelines on the management of valvular heart disease—supported by the European Society of Cardiology (ESC) and European Association of CardioThoracic Surgery (EACTS)—were recently published. Although these guidelines are very comprehensive, these typically are not very inviting to read. In this document, we aimed to distil all the information about transcatheter aortic valve replacement (TAVR) in the new 2017 ESC/EACTS guidelines to the essential and give additional comments on the position of TAVR in 2017.

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.

Access site complications in transcutaneous aortic valve replacement: frequency, outcomes, prevention, and treatment

Aortic stenosis (AS) is a common cause of valvular heart disease with heavy disease burden in elderly patients. It is present in almost 7% of patients older than 65. The mortality rate increases significantly once it becomes symptomatic with average life expectancy of around 1-year. Symptoms include angina, syncope, or heart failure. This requires either surgical or transcutaneous replacement. Transcutaneous aortic valve replacement (TAVR) use has increased in recent years from high risk patients to now even including intermediate risk patients. With the increased number of procedures performed, one of the consequences is access site complications. These complications can lead to increased hospitalization, cost, infections, and eventually worse outcomes. In this manuscript, we provide a comprehensive review discussing the consequences, outcomes, frequency, predictors and some possible solutions to these complications set forth in these studies.

Transcatheter aortic valve replacement in intermediate and low risk patients-clinical evidence

The encouraging results of the PARTNER 2 (Placement of AoRtic TraNscathetER Valves 2) trial led to the approval of transcatheter aortic valve replacement (TAVR) in intermediate-surgical-risk patients. Recently, the SURTAVI (SUrgical Replacement and Transcatheter Aortic Valve Implantation) investigators demonstrated the feasibility of TAVR with self-expanding valves in intermediate-risk patients. The focus has now shifted to clinical trials comparing TAVR to surgery in low-surgical-risk populations with a goal to expand TAVR to all-risk patients. However, low-surgical-risk patients continue to be acceptable candidates for surgical aortic valve replacement, with proven outcomes over many decades. Although new data has emerged showing feasibility of TAVR in young patients with bicuspid valves, with newer generation TAVR valves there will be minimal tolerance for adverse outcomes in the low risk category. To expand the reach of TAVR into low-surgical-risk patients, important questions about valve durability, leaflet thrombosis, higher rates of paravalvular leak and permanent pacemakers (PPM) will need to be addressed. However, as TAVR technology continues to evolve, it seems to be just a matter of time before TAVR establishes itself as a modality for aortic valve replacement regardless of surgical risk.

Outcomes of surgical and transcatheter aortic valve replacement in the octogenarians-surgery still the gold standard?

BACKGROUND

Contemporary options for aortic valve replacement (AVR) include transcatheter and surgical approaches (TAVR and SAVR). As evidence accrues for TAVR in high and intermediate risk patients, some clinicians advocate that all patients aged over 80 years should only receive TAVR. Our aim was to investigate the utility of SAVR and minimally invasive AVR (mAVR) among octogenarians in the current era of TAVR.

METHODS

From 2002 to 2015, 1,028 octogenarians underwent isolated AVR; 306 TAVR and 722 SAVR, of which 378 patients underwent mAVR. Logistic regression and Cox modeling were used to evaluate overall operative mortality and mid-term survival, respectively. Patients were stratified based on procedural approaches (mAVR or full sternotomy for SAVR, and transfemoral or alternate access for TAVR). Median follow-up was 35 [interquartile range (IQR) 14-65] months.

RESULTS

Compared to SAVR patients, TAVR patients were relatively older (86.2 versus 84.2 years) with co-morbidities such as chronic kidney disease (CKD), diabetes mellitus (DM), cerebrovascular disease (CVD), and prior myocardial infarction (MI), all P<0.05. The mean STS-PROM for the TAVR group was statistically higher, 6.81 versus 5.58 for the SAVR group (P<0.001). The median in-hospital LOS was statistically higher for the SAVR group (P<0.05). Cox proportional hazard modeling, adjusted for temporal differences in procedure and patient selection, identified age, New York Heart Association (NYHA) class III/IV, preoperative creatinine, severe chronic lung disease, prior cardiac surgery as significant predictors of decreased survival (all P<0.05), while type of intervention (approach) was non-contributory. Adjusted operative mortality stratified by procedure approaches was similar between full sternotomy SAVR and mAVR, and between alternative access and transfemoral TAVR.

CONCLUSIONS

After adjusting for confounders, TAVR (regardless of approach), SAVR, and mAVR had comparable operative mortality and mid-term survival. Treatment decisions should be individualized with consensus from a multi-disciplinary heart team, taking into account patient co morbidities, frailty, and quality of life. We believe certain patient groups will still benefit from SAVR even in this elderly population.

The association between renal recovery after acute kidney injury and long-term mortality after transcatheter aortic valve replacement

Background

This study aimed to examine the association between renal recovery status at hospital discharge after acute kidney injury (AKI) and long-term mortality following transcatheter aortic valve replacement (TAVR).

Methods

We screened all adult patients who survived to hospital discharge after TAVR for aortic stenosis at a quaternary referral medical center from January 1, 2008, through June 30, 2014. An AKI was defined as an increase in serum creatinine level of 0.3 mg/dL or a relative increase of 50% from baseline. Renal outcome at the time of discharge was evaluated by comparing the discharge serum creatinine level to the baseline level. Complete renal recovery was defined as no AKI at discharge, whereas partial renal recovery was defined as AKI without a need for renal replacement therapy at discharge. No renal recovery was defined as a need for renal replacement therapy at discharge.

Results

The study included 374 patients. Ninty-eight (26%) patients developed AKI during hospitalization: 55 (56%) had complete recovery; 39 (40%), partial recovery; and 4 (4%), no recovery. AKI development was significantly associated with increased risk of 2-year mortality (hazard ratio [HR], 2.20 [95% CI, 1.37–3.49]). For patients with AKI, the 2-year mortality rate for complete recovery was 34%; for partial recovery, 43%; and for no recovery, 75%; compared with 20% for patients without AKI (P < .001). In adjusted analysis, complete recovery (HR, 1.87 [95% CI, 1.03–3.23]); partial recovery (HR, 2.65 [95% CI, 1.40–4.71]) and no recovery (HR, 10.95 [95% CI, 2.59–31.49]) after AKI vs no AKI were significantly associated with increased risk of 2-year mortality.

Conclusion

The mortality rate increased for all patients with AKI undergoing TAVR. A reverse correlation existed for progressively higher risk of death and the extent of AKI recovery.

Review of Major Registries and Clinical Trials of Late Outcomes After Transcatheter Aortic Valve Replacement

The results of the Placement of AoRtic TraNscathetER Valves (PARTNER) 2 trial established the feasibility of transcatheter aortic valve replacement (TAVR) for intermediate surgical risk patients. The expansion of TAVR into the low-risk patient population will largely depend on its durability outcomes due to the high life expectancy in low-risk patients. Long-term follow-up results from low-risk clinical trials will take several years to be reported. Given this, we performed a systematic review of current long-term data to provide further insights into TAVR durability and long-term patient survival. We searched MEDLINE, Embase, Google Scholar, BIOSIS, and major conference abstracts for TAVR studies with follow-up of at least 4 years. Abstracts were retrieved and independently reviewed for eligibility. Final studies were selected irrespective of the type of TAVR valve, route of vascular access, or surgical risk profile. A total of 12 studies met the inclusion criteria. We reviewed data from these studies with emphasis on long-term survival and echocardiographic findings.