Surgical sutureless and transcatheter aortic valves: hemodynamic performance and clinical outcomes in propensity score-matched high-risk populations with severe aortic stenosis

Heart failure hospitalization following surgical or transcatheter aortic valve implantation in low-risk aortic stenosis

AIMS

In low-risk patients with severe aortic stenosis (AS), sutureless surgical aortic valve replacement (SU-SAVR) may be an alternative to transcatheter aortic valve implantation (TAVI). The risk of heart failure hospitalization (HFH) after aortic valve replacement (AVR) in this population is incompletely characterized. This study aims to investigate the incidence, predictors, and outcomes of HFH in patients undergoing SU-SAVR versus TAVI.

METHODS AND RESULTS

Patients referred for AVR between 2013 and 2020 at two centres were consecutively included. The decision for SU-SAVR or TAVI was determined by a multidisciplinary Heart Team. Cox regression and competing risk analysis were conducted to assess adverse events. Of 594 patients (mean age 77.5 ± 6.4, 59.8% male), 424 underwent SU-SAVR, while 170 underwent TAVI. Following a mean follow-up of 34.1 ± 23.1 months, HFH occurred in 112 (27.8%) SU-SAVR patients and in 8 (4.8%) TAVI patients (P < 0.001). The SU-SAVR cohort exhibited higher all-cause mortality (138 [32.5%] patients compared with 30 [17.6%] in the TAVI cohort [P < 0.001]). These differences remained significant after sensitivity analyses with 1:1 propensity score matching for baseline variables. SU-SAVR with HFH was associated with increased all-cause mortality (61.6% vs. 23.1%, P < 0.001). Independent associates of HFH in SU-SAVR patients included diabetes, atrial fibrillation, chronic obstructive pulmonary disease, lower glomerular filtration rate and lower left ventricular ejection fraction. SU-SAVR patients with HFH had a 12-month LVEF of 59.4 ± 12.7.

CONCLUSIONS

In low-risk AS, SU-SAVR is associated with a higher risk of HFH and all-cause mortality compared to TAVI. In patients with severe AS candidate to SU-SAVR or TAVI, TAVI may be the preferred intervention.

Hemodynamic Performance of Transcatheter Aortic Valves: A Comprehensive Review

Transcatheter aortic valve implantation (TAVI) is a widely adopted treatment option for patients with severe aortic stenosis. Its popularity has grown significantly in recent years due to advancements in technology and imaging. As TAVI use is increasingly expanded to younger patients, the need for long-term assessment and durability becomes paramount. This review aims to provide an overview of the diagnostic tools to evaluate the hemodynamic performance of aortic prosthesis, with a special focus on the comparison between transcatheter and surgical aortic valves and between self-expandable and balloon-expandable valves. Moreover, the discussion will encompass how cardiovascular imaging can effectively detect long-term structural valve deterioration.

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.

Comparison of Sutureless Bioprosthetic Valve With Surgical or TAVR for Severe Aortic Stenosis

Background

Clinical advantages of sutureless rapid-deployment (RD) aortic valve replacement (AVR) for severe aortic valve stenosis (AS) have not been elucidated compared with surgical (SAVR) or transcatheter (TAVR) aortic valve replacement.

Objectives

This study sought to investigate comparative effectiveness and safety of RD-AVR compared with SAVR and TAVR in a prospective cohort of patients with severe AS.

Methods

The primary outcome was a composite of death, stroke, or rehospitalization at 12 months. Propensity score matching was used to assemble a cohort of patients with similar baseline characteristics.

Results

Among 1,020 eligible patients, 107 (10.5%) underwent RD-AVR, 437 (42.8%) underwent SAVR, and 476 (46.7%) underwent TAVR. In the matched cohorts of RD-AVR and SAVR (n = 107), the incidence of primary composite outcome at 12 months was similar between the 2 groups (8.0% vs 10.8%, respectively; hazard ratio [HR]: 0.74; 95% confidence interval [CI]: 0.30-1.84; P = 0.52). In the matched cohorts of RD and TAVR (n = 58), the incidence of primary composite outcome at 12 months did not statistically differ between the 2 groups (9.4% vs 16.2%, respectively; HR: 0.53; 95% CI: 0.18-1.57; P = 0.25).

Conclusions

In this propensity-matched cohort of patients who underwent AVR for severe AS, we did not detect significant differences in the rates of the primary composite of death, stroke, or rehospitalization at 12 months when comparing RD-AVR with SAVR and TAVR. Because the study was underpowered, the results should be considered as hypothesis generating highlighting the need for further research. (ASAN Medical Center Aortic Valve Replacement Registry [ASAN-AVR]; NCT03298178)

Outcomes of sutureless aortic valve replacement versus conventional aortic valve replacement and transcatheter aortic valve replacement, updated systematic review, and meta-analysis

BACKGROUND

Sutureless aortic valve replacement (SuAVR) is an alternative to surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR). This study compares the effectiveness of SuAVR to SAVR and TAVR.

METHODS

We searched MEDLINE and EMBASE from inception to July 2021 for studies evaluating SuAVR, SAVR, and TAVR in adults with aortic stenosis. We performed screening, full-text assessment, data collection, and risk of bias evaluation independently and in duplicate. We evaluated risk of bias using by Cochrane and CLARITY's tools, and certainty in evidence using the GRADE framework. Data were pooled using a random-effects model.

RESULTS

We identified one randomized and 78 observational studies (n = 60,689; SuAVR vs. SAVR = 39,171, vs. TAVR = 21,518). All studies were at high or unclear risk of bias, with very-low certainty in effect estimates. Compared to TAVR, SuAVR demonstrates no significant difference in mortality at 30-days (odds ratio [OR]: 0.52, 95% confidence interval [CI: 0.85, 1.16], I²  = 0%), but decreased odds at 2-years (OR: 0.39, 95% CI [0.17, 0.88], I²  = 0%). SuAVR also reduced odds of mild paravalvular regurgitation (OR: 0.11, 95% CI [0.06, 0.21], I²  = 50%). Compared to SAVR, SuAVR was associated with a similar mortality at 30-days (OR: 0.99, 95% CI [0.85, 1.16], I²  = 0%) and 2-years (OR: 0.99, 95% CI [0.43-2.30], I²  = 7%). SuAVR significantly increased odds of permanent pacemaker implantation (OR: 2.5, 95% CI [2.25, 2.77], I²  = 0%). Pooled effect estimates were consistent with results from the randomized trial comparing SuAVR and SAVR.

CONCLUSION

Based on very-low quality evidence, SuAVR is associated with similar short- and midterm outcomes compared to TAVR and SAVR. Comparative randomized data with long-term follow-up are required to clarify the role of SuAVR.

Are Sutureless and Rapid-Deployment Aortic Valves a Serious Alternative to TA-TAVI? A Matched-Pairs Analysis

BACKGROUND

Transcatheter aortic valve implantation is a feasible alternative to conventional aortic valve replacement with expanding indication extending to low-risk patients. Sutureless and rapid-deployment aortic valves were developed to decrease procedural risks in conventional treatment. This paired-match analysis aims to compare patients undergoing surgical transcatheter aortic valve implantation to sutureless and rapid-deployment aortic valve implantation.

METHODS

Retrospective database analysis between 2010 and 2016 revealed 214 patients undergoing transcatheter aortic valve implantation procedures through surgical access (predominantly transapical) and 62 sutureless and rapid-deployment aortic valve procedures including 26 patients in need of concomitant coronary artery bypass surgery. After matching, 52 pairs of patients were included and analyzed.

RESULTS

In-hospital death (5.8% vs. 3.8%; p = 0.308) was comparable between transcatheter aortic valve implantation (mean age 77 ± 4.3 years) and sutureless and rapid-deployment aortic valve implantation groups (mean age 75 ± 4.0 years), including 32 females in each group. The logistic EuroSCORE was similar (19 ± 12 vs. 17 ± 10; p = 0.257). Postoperative renal failure (p = 0.087) and cerebrovascular accidents (p = 0.315) were without significant difference. The incidence of complete heart block requiring permanent pacemaker treatment was relatively low for both groups (1.9% vs. 7.7%; p = 0.169) for TAVI and sutureless and rapid-deployment valves respectively. Intraoperative use of blood transfusion was higher in the sutureless and rapid-deployment aortic valve implantation group (0.72 U vs. 1.46 U, p = 0.014). Estimated survival calculated no significant difference between both groups after 6 months (transcatheter aortic valve implantation: 74 ± 8% vs. sutureless and rapid-deployment aortic valve implantation: 92 ± 5%; log rank p = 0.097).

CONCLUSION

Since sutureless and rapid-deployment aortic valve implantation is as safe and effective as transapical transcatheter aortic valve implantation, combining the advantage of standard diseased-valve removal with shorter procedural times, sutureless and rapid-deployment aortic valve replacement may be considered as an alternative for patients with elevated operative risk considered to be in the "gray zone" between transcatheter aortic valve implantation and conventional surgery, especially if concomitant myocardial revascularization is required.

Sutureless aortic valve prostheses

Conventional surgical aortic valve replacement (AVR) is the 'gold standard' for treatment of severe or symptomatic aortic valve stenosis. The increasing age of patients and increasing comorbidities has led to the development of procedures to minimise operative time and reduce risks of surgery. One method of reducing operative times is the use of sutureless aortic valves (SU-AVR). We examine the current literature surrounding the use of SU-AVR. Alternatives to AVR are SU-AVR, sometimes referred to as rapid deployment valves, or transcatheter aortic valve implantation (TAVI). TAVI has been demonstrated to be superior over medical therapy in patients deemed inoperable and non-inferior in high and intermediate-risk patients compared with surgical AVR. However, the lack of excision of the calcified aortic valve and annulus raises concerns regarding long-term durability and possibly thromboembolic complications. TAVI patients have increased rates of paravalvular leaks, major vascular complications and pacemaker implantation when compared with conventional AVR. SU-AVR minimises the need for suturing, leading to reduced operative times, while enabling complete removal of the calcified valve. The increase in use of SU-AVR has been mostly driven by minimally invasive surgery. Other indications include patients with a small and/or calcified aortic root, as well as patients requiring AVR and concomitant surgery. SU-AVR is associated with decreased operative times and possibly improved haemodynamics when compared with conventional AVR. However, this has to be weighed against the increased risk of paravalvular leak and pacemaker implantation when deciding which prosthesis to use for AVR.

Incidence, predictors, and outcome of prosthesis-patient mismatch after transcatheter aortic valve replacement: A meta-analysis

BACKGROUND

Prosthesis-patient mismatch (PPM) following transcatheter aortic valve replacement (TAVR) is common, but the incidence, predictors and outcome of PPM are still controversial.

METHODS

A total of 18 articles incorporating 72,016 patients were identified form PubMed and Embase online database.

RESULTS

The pooled incidences of overall, and severe PPM following TAVR were 32.0% and 10.0% separately. Comparing to surgical aortic valve replacement (SAVR), TAVR had lower incidence of overall (OR, 0.31, 95% CI, 0.20-0.50) and severe PPM (OR, 0.38, 95% CI, 0.28-0.52). PPM was associated with a larger body surface area (BSA), larger body mass index (BMI) and previous myocardial infarction in comparison with those patients without PPM. Although PPM was not rare after TAVR, no significant differences were observed both in short- and mid-term all-cause mortality (30 day: OR: 1.51, 95% CI, 0.79-2.87, 1 year: OR: 1.02, 95% CI, 0.96-1.08, and 2 years: OR: 0.99, 95% CI, 0.79-1.24) between patients with PPM and those without PPM.

CONCLUSIONS

Despite the fact that the incidence of PPM was lower than that of SAVR, PPM was not seen to have an impact on short- and mid-term survival.

Valve Hemodynamics Following Transcatheter or Surgical Aortic Valve Replacement in Patients With Small Aortic Annulus

This study aimed to compare the hemodynamic performance of transcatheter and surgical aortic valves in patients with severe symptomatic aortic stenosis and small aortic annulus (SAA) and to determine the valve hemodynamics according to transcatheter valve type. Consecutive surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) patients with SAA were case-matched (1:1) on the basis of sex, body surface area, aortic annulus diameter, and left ventricular ejection fraction. A total of 357 patients in each group constituted the final study population. A second match on the basis of aortic annulus diameter and valve/annulus calcium burden was performed within the TAVR group to compare the valve performance between balloon- (n = 52) and self-expanding (n = 52) transcatheter valve systems (BEV, SEV). The echocardiograms performed at hospital discharge were used for evaluating valve hemodynamics. The mean annulus diameter of the study population was 19.2 ± 0.3 mm. The TAVR group (vs SAVR) exhibited lower mean gradient (12 ± 7 mm Hg vs 15 ± 6 mm Hg, p <0.001), larger effective orifice area (1.46 ± 0.39 cm² vs 1.25 ± 0.37 cm², p <0.001) and a lower rate of severe prosthesis-patient mismatch (PPM) (14% vs 24%, p = 0.001). Moderate-severe AR was present in 2.5% of the TAVR recipients versus none patient in the SAVR group. There were no differences in valve hemodynamics between balloon-expanding transcatheter valve system and self-expanding transcatheter valve system, and similar rates of severe PPM were observed in both groups (p = 0.488). In conclusion, TAVR presented superior valve hemodynamics and lower incidence of severe PPM compared with SAVR in SAA patients. Similar valve performance results were observed between transcatheter valve types.

Men are from mars, women are from venus: Factors responsible for gender differences in outcomes after surgical and trans-catheter aortic valve replacement

Females suffer higher operative (30-day) mortality than males after surgical aortic valve replacement (SAVR). In contrast, outcomes after trans-catheter aortic valve replacement (TAVR) seem to favor females, both in terms of procedural mortality, and more prominently, medium to long-term survival. With an ever-greater number of TAVR procedures being performed, an understanding of factors responsible for gender differences in outcomes after the two AVR modalities is critical for better patient selection. Current evidence suggests that this gender difference in outcomes after SAVR and TAVR stems from differences in baseline risk profiles, as well as inherent anatomic/physiological differences between genders. This review attempts to examine these clinical and physiological factors, with a goal of guiding better patient selection for each AVR modality, and to highlight areas that beg further investigation.

Current Key Issues in Transcatheter Aortic Valve Replacement Undergoing a Paradigm Shift

As a new technology in the management of valvular heart disease, transcatheter aortic valve replacement (TAVR) has drawn much attention since its emergence. To date, numerous studies have investigated the safety and efficacy of TAVR in patients of various risk profiles with severe aortic stenosis (AS) and demonstrated comparable or superior outcomes of TAVR when compared with surgical aortic valve replacement (SAVR). The favorable outcomes of TAVR in inoperable patients, as well as in high- and intermediate-risk patients, are endorsed in current guidelines, and trials of low-risk patients have shown non-inferior or even superior results of TAVR than for SAVR, suggesting that the clinical indications of TAVR can be expanded to low-risk patients. Moreover, a therapeutic role of TAVR has been suggested in various aortic valve (AV) diseases, such as bicuspid AV, moderate AS with heart failure, aortic regurgitation, and bioprosthetic valve failure. In this review, we summarize the current issues of TAVR in various patient populations and discuss the expanding clinical indications of TAVR, which are driving a major paradigm shift in the management of AV disease.

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.

Sutureless aortic valves: who is the right patient?

PURPOSE OF REVIEW

Sutureless aortic valve replacement (AVR) has emerged as an alternative to traditional AVR for patients with aortic stenosis who present a higher surgical risk, such as the elderly, or those with small or highly calcified aortic roots. With transcatheter aortic valve implantation - the other major AVR alternative - being used in increasingly lower-risk patients, the place of sutureless valves in the AVR landscape needs to be defined. In this review, we discuss recent data and expert opinion as it pertains to the subject of sutureless AVR.

RECENT FINDINGS

Several recent studies have evaluated the performance of sutureless valves in a variety of clinical contexts, including minimally invasive operations and high-risk surgical procedures. The optimal surgical technique for sutureless AVR has been refined through the publication of several reports addressing technical considerations. Reduction in operative times represents the main advantage of sutureless valves over conventional surgical prostheses, and the possibility of complete annular decalcification - and hence a reduced incidence of paravalvular leak - is the primary advantage over TAVI.

SUMMARY

Sutureless valves have emerged as an attractive option for high-risk patients or for complex surgeries where a minimization of bypass time is critical. However, there is limited data regarding long-term outcomes, durability or reoperation.

Patient-prosthesis mismatch in patients treated with transcatheter aortic valve implantation - predictors, incidence and impact on clinical efficacy. A preliminary study

Introduction

Patient-prosthesis mismatch (PPM) is relatively frequent after surgical aortic valve replacement (SAVR) and negatively impacts prognosis.

Aim

We sought to determine the frequency and clinical effects of PPM after transcatheter aortic valve implantation (TAVI).

Material and methods

Overall, 238 patients who underwent TAVI were screened. Moderate PPM was defined as indexed effective orifice area (EOAi) between 0.65 and 0.85 cm²/m², and severe PPM as < 0.65 cm²/m². All-cause mortality and the Valve Academic Research Consortium 2 (VARC-2) defined composite of clinical efficacy at 1 year were the primary endpoints.

Results

Finally, 201 patients were included (mean age: 79.6 ±7.4 years, 52% females). The femoral artery served as the delivery route in 79% and most of the prostheses were self-expanding (68%). Any PPM was present in 48 (24%) subjects, and only 7 (3.5%) had severe PPM. Body surface area (BSA) independently predicted any PPM (OR = 16.9, p < 0.001) whereas post-dilation tended to protect against PPM (OR = 0.46, p = 0.09). All-cause mortality was similar in patients with moderate or severe PPM as compared to those with no PPM (14.6% vs. 14.3% vs. 13.1%, respectively, log-rank p = 0.98). Neither moderate (OR = 1.6, 95% CI: 0.8-3.2, p = 0.16) nor severe PPM (OR = 1.67, 95% CI: 0.36-7.7, p = 0.51) had a significant impact on composite endpoint, or its elements, with the exception of transvalvular pressure gradient > 20 mm Hg.

Conclusions

Severe PPM after TAVI is rare, can be predicted by larger BSA and does not seem to affect mid-term mortality or composite clinical outcome. Larger studies are needed to find different independent predictors of PPM and elucidate its impact in terms of device durability and long-term clinical efficacy.

Incidence, Predictors and Outcome of Prosthesis-Patient Mismatch after Transcatheter Aortic Valve Replacement: a Systematic Review and Meta-analysis

The aim of this study was to investigate the incidence, predictors and outcome of prosthesis-patient mismatch (PPM) following transcatheter aortic valve replacement (TAVR). A total of 30 articles incorporating 4,691 patients were identified. The pooled incidences of overall, moderate and severe PPM following TAVR were 33.0%, 25.0% and 11.0% respectively. Medtronic CoreValve (MCV) had lower incidence of overall (32% vs: 40%, P < 0.0001) and moderate (23% vs 32%, P < 0.0001) than Edwards Sapien (ESV). PPM was associated with a younger age, smaller annulus diameter and lower left ventricular ejection fraction in comparison with those patients without PPM. Post-dilation (OR, 0.51, 95% CI, 0.38 to 0.68, p < 0.001) during TAVR would decrease the incidence of PPM. Although PPM was common after TAVR, no significant differences were observed both in short- and mid-term all-cause mortality (30 day: OR: 1.1, 95% CI, 0.70 to 1.73 and 2 year: OR: 1.01, 95% CI, 0.74 to 1.38) between patients with PPM and those without PPM. In conclusion, despite being common after TAVR, the incidence of PPM was lower than that of surgical aortic valve replacement (SAVR) and decreased with the experience accumulating, and PPM was not seen to impact on short- and mid-term survival, regardless of its magnitude.

Prosthesis-patient mismatch - what cardiac anesthesiologists need to know?

Prosthesis-patient Mismatch (PPM) is not uncommon with an incidence reported up to 70% after aortic valve (AV) replacement. Severe forms of PPM are less common (up to 20%); PPM can lead to increased short- and long-term morbidity and mortality. It is important to discriminate PPM from other forms of prosthetic valve dysfunction. Sometimes, prosthetic valve degenerative disease may coexist with PPM. Echocardiography plays an important role in the prevention and diagnosis of PPM. Preemptive strategies to prevent PPM include insertion of newer generation prosthetic valves with better hemodynamic characteristics, stentless prosthesis, aortic root enlargement to insert a larger prosthesis, aortic homograft, and transcutaneous AV implantation. We present an illustrative case and review the literature on PPM pertinent to anesthesiologists.

Comparison of hemodynamic and clinical outcomes of transcatheter and sutureless aortic bioprostheses: how to make the right choice in intermediate risk patients

Current surgical treatment options for aortic valve stenosis (AS), as alternatives to that of conventional operation with a midline sternotomy, include sutureless valve replacement (SUAVR) and transcatheter valve implantation (TAVI). Patients with high surgical risk, or those who are judged to be inoperable, are typically good candidates for the TAVI procedure. The best treatment option in patients with an intermediate risk profile, however, the so called "grey zone", is still currently under debate. Sutureless aortic valve replacement has been recently presented as a valid alternative for patients with low- to intermediate-risk. Data available on prostheses' hemodynamic performance and patients' clinical outcomes play a crucial role in the process of device selection. Compared to TAVI, SUAVR provides lower rate of significant postoperative paravalvular leak (PVL), which has shown to be a predictor for mortality. On the contrary, transcatheter valves seem to perform better in terms of transvalvular mean and peak gradients. Therefore, SUAVR and TAVI are both reliable options in patients with severe aortic valve stenosis, as an alternative to conventional surgery, and the choice of the best device should be tailored to patient's anatomical and surgical characteristics.

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

BACKGROUND

Transcatheter aortic valve replacement (TAVR) has emerged as the treatment of choice for patients with severe aortic stenosis at high surgical risk; the role of TAVR compared with surgical aortic valve replacement (SAVR) in the low-intermediate surgical risk population remains uncertain. Our primary objective was to determine differences in 30-day and late mortality in patients treated with TAVR compared with SAVR at low-intermediate risk (Society of Thoracic Surgeons Predicted Risk of Mortality < 10%).

METHODS

Medline and Embase were searched from 2010 to March 2017 for studies that compared TAVR with SAVR in the low-intermediate surgical risk population, restricted to randomized clinical trials and matched observational studies. Two investigators independently abstracted the data and a random effects meta-analysis was performed.

RESULTS

Four randomized clinical trials (n = 4042) and 9 propensity score-matched observational studies (n = 4192) were included in the meta-analysis (n = 8234). There was no difference in 30-day mortality between TAVR and SAVR (3.2% vs 3.1%, pooled risk ratio: 1.02; 95% confidence interval, 0.80-1.30; P = 0.89; I² = 0%) or mortality at a median of 1.5-year follow-up (incident rate ratio: 1.01; 95% confidence interval, 0.90-1.15; P = 0.83; I² = 0%). There was a higher risk of pacemaker implantation and greater than trace aortic insufficiency in the TAVR group whereas the risk of early stroke, atrial fibrillation, acute kidney injury, cardiogenic shock, and major bleeding was higher in the SAVR group.

CONCLUSIONS

Although there was no difference in 30-day and late mortality, the rate of complications differed between TAVR and SAVR in the low-intermediate surgical risk population.

Sutureless Aortic Valves: Combining the Best or the Worst?

Aortic valve replacement is a life saving intervention. Significant progress has been made toward reducing surgical trauma through minimally invasive surgery and transcatheter techniques. Each of these approaches has its advantages and limitations. Sutureless aortic valves have been proposed to overcome these limitations and have been in use in Europe. It is however less than clear whether these valves will prove advantageous and whether they will have a role in the future. We review the published literature for sutureless aortic valves and their performance against standard and transcatheter aortic valve replacements.

Transcatheter aortic valve implantation (TAVI) versus sutureless aortic valve replacement (SUAVR) for aortic stenosis: a systematic review and meta-analysis of matched studies

BACKGROUND

With improving technologies and an increasingly elderly populations, there have been an increasing number of therapeutic options available for patients requiring aortic valve replacement. Recent evidence suggests that transcatheter aortic valve implantation (TAVI) is one suitable option for high risk inoperable patients, as well as high risk operable patients. Sutureless valve technology has also been developed concurrently, with facilitates surgical aortic valve replacement (SUAVR) by allow resection and replacement of the native aortic valve with minimal sutures and prosthesis anchoring required. For patients amenable for both TAVI and SUAVR, the evidence is unclear with regards to the benefits and risks of either approach. The objectives are to compare the perioperative outcomes and intermediate-term survival rates of TAVI and SUAVR in matched or propensity score matched studies.

METHODS

A systematic literature search was performed to include all matched or propensity score matched studies comparing SUAVR versus TAVI for severe aortic stenosis. A meta-analysis with odds ratios (OR) and mean differences were performed to compare key outcomes including paravalvular regurgitation and short and intermediate term mortality.

RESULTS

Six studies met our inclusion criteria giving a total of 741 patients in both the SUAVR and TAVI arm of the study. Compared to TAVI, SUAVR had a lower incidence of paravalvular leak (OR =0.06; 95% CI: 0.03-0.12, P<0.01). There was no difference in perioperative mortality, however SUAVR patients had significantly better survival rates at 1 (OR =2.40; 95% CI: 1.40-4.11, P<0.01) and 2 years (OR =4.62; 95% CI: 2.62-8.12, P<0.01).

CONCLUSIONS

The present study supports the use of minimally invasive SUAVR as an alternative to TAVI in high risk patients requiring aortic replacement. The presented results require further validation in prospective, randomized controlled studies.

Acute kidney injury following cardiac surgery: current understanding and future directions

Acute kidney injury (AKI) complicates recovery from cardiac surgery in up to 30 % of patients, injures and impairs the function of the brain, lungs, and gut, and places patients at a 5-fold increased risk of death during hospitalization. Renal ischemia, reperfusion, inflammation, hemolysis, oxidative stress, cholesterol emboli, and toxins contribute to the development and progression of AKI. Preventive strategies are limited, but current evidence supports maintenance of renal perfusion and intravascular volume while avoiding venous congestion, administration of balanced salt as opposed to high-chloride intravenous fluids, and the avoidance or limitation of cardiopulmonary bypass exposure. AKI that requires renal replacement therapy occurs in 2–5 % of patients following cardiac surgery and is associated with 50 % mortality. For those who recover from renal replacement therapy or even mild AKI, progression to chronic kidney disease in the ensuing months and years is more likely than for those who do not develop AKI. Cardiac surgery continues to be a popular clinical model to evaluate novel therapeutics, off-label use of existing medications, and nonpharmacologic treatments for AKI, since cardiac surgery is fairly common, typically elective, provides a relatively standardized insult, and patients remain hospitalized and monitored following surgery. More efficient and time-sensitive methods to diagnose AKI are imperative to reduce this negative outcome. The discovery and validation of renal damage biomarkers should in time supplant creatinine-based criteria for the clinical diagnosis of AKI.

Aortic valve replacement and prosthesis-patient mismatch in the era of trans-catheter aortic valve implantation

Objective

The treatment strategy for aortic stenosis (AS) has been changing due to newly developed valvular prostheses and trans-catheter aortic valve implantation (TAVI). To determine the role of new modalities for AS with a small aortic root, papers using the concept of prosthesis-patient mismatch (PPM) were reviewed.

Methods

First, to determine the cut-off value of the indexed effective orifice area (IEOA) for defining PPM, the studies of surgical aortic valve replacement (SAVR) with a follow-up longer than 5 years and a patient number larger than 500 were reviewed. Second, the papers comparing TAVI and SAVR were reviewed. Furthermore, the prevalence of PPM was reviewed, with the addition of papers on aortic root enlargement, sutureless AVR, and aortic valve reconstruction with autologous pericardium.

Results and conclusion

The results of the long-term survival after aortic valve replacement (AVR) have indicated that an IEOA less than 0.65 cm²/m² should be avoided in all cases, whereas the indications for patients with an IEOA between 065 and 0.85 cm²/m² should be determined by considering multiple factors. A large body size and younger age have a significantly negative influence on the long-term survival. In Asian population, the prevalence of PPM was low, despite the fact that the size of the aortic annulus was small. The IEOA after TAVI was larger than after surgical AVR in population-matched studies. To evaluate the role of TAVI and other modalities for a small aortic root, studies with a longer follow-up and larger volume are thus warranted.

Geometric changes in ventriculoaortic complex after transcatheter aortic valve replacement and its association with post-procedural prosthesis-patient mismatch: an intraprocedural 3D-TEE study

AIMS

Prosthesis-patient mismatch (PPM) after transcatheter aortic valve replacement (TAVR) leads to increased mortality. However, its peri-procedural determinants remain unknown. We investigated geometric changes in aortic annulus (AoA) and left ventricular outflow tract (LVOT) during TAVR by three-dimensional transoesophageal echocardiography (3D-TEE) and its association with post-procedural PPM.

METHODS AND RESULTS

A total of 131 patients with severe aortic stenosis underwent intraprocedural 3D-TEE during balloon-expandable TAVR. The severity of PPM was graded using the indexed effective orifice area calculated by Doppler echocardiography at discharge, with moderate defined as ≥0.65 and ≤0.85 cm²/m² and severe defined as <0.65 cm²/m². 3D planimetered AoA area decreased after TAVR (P< 0.001), whereas the LVOT increased (P= 0.004). The eccentricity of both AoA and LVOT decreased after TAVR (both, P< 0.001). At discharge, the incidence of overall and severe PPM was 44 and 12%, respectively. Patients with PPM had a larger body surface area, smaller aortic valve area, and less frequent balloon dilation (all P< 0.05). Patients with PPM had a lower post-TAVR AoA area/pre-TAVR AoA area (91 ± 8 vs. 95 ± 7%, P= 0.001) than those without PPM. The post-TAVR AoA area/pre-TAVR AoA area was independently associated with overall PPM (odds ratio, 1.80; 95% CI, 1.06-3.05; P= 0.031) and severe PPM (odds ratio, 2.50; 95% CI, 1.05-5.36; P= 0.04). Additionally, a cut-off value of this ratio >86.3% had a sensitivity of 84% and a specificity of 44% for the prevention of severe PPM.

CONCLUSION

3D-TEE can evaluate geometric changes in AoA and LVOT during balloon-expandable TAVR and predicts post-procedural PPM.