Minimally invasive aortic valve replacement with sutureless valve is the appropriate treatment option for high-risk patients and the “real alternative” to transcatheter aortic valve implantation

Considering alternatives to transcatheter heart valves for managing patients with severe aortic valve stenosis

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) is becoming the standard of care for severe symptomatic aortic stenosis (AS). Yet, some patients with AS are not indicated/eligible for TAVI. Several noninvasive, catheter-based or surgical alternatives exist, and other therapeutic options are emerging.

AREAS COVERED

This review provides an overview of non-TAVI options for severe AS. Non-invasive, transcatheter, and alternative surgical strategies are discussed, emphasizing their backgrounds, techniques, and outcomes.

EXPERT OPINION

Alternative therapies to TAVI, whether device-based or non-device-based, continue to evolve or emerge and provide either alternative treatments or a bridge to TAVI, for patients not meeting indications for, or having contraindications to TAVI.Although TAVI and SAVR are the current dominant therapies, there are still some patients that could benefit in the future from other alternatives.Data on alternative options for such patients are scarce. Many advantages and disadvantages arise when selecting a specific treatment strategy for individual patients.Head-to-head comparison studies could guide physicians toward better patient selection and procedural planning. Awareness of therapeutic options, indications, techniques, and outcomes should enable heart teams to achieve optimized patient selection. Furthermore, it can increase the use of these alternatives to optimize the management of AS among different patient populations.

Aortic Root Dissection Due to an Automated Fastener Device

Minimally invasive aortic valve replacement through a right thoracotomy is frequently performed in patients with aortic valve disease. The Cor-Knot Device (LSI Solutions) is an automated fastener that secures valve sutures. This case report is for a patient who developed postcardiotomy shock during a minimally invasive aortic valve surgery. The patient was found to have an aortic root dissection involving 90% of the aortic root circumference, including bilateral coronary ostia. The autopsy revealed that the aortic damage could be explained by a direct aortic intimal tear from the distal tip of the device shaft. The device was most likely not in perfect apposition to the sewing ring because of the restricted angle and space between the ribs.

Sutureless Valve in Repeated Aortic Valve Replacement: Results from an International Prospective Registry

OBJECTIVE

To report early and midterm results registry of patients undergoing repeated aortic valve replacement (RAVR) with sutureless prostheses from an international prospective registry (SURE-AVR).

METHODS

Between March 2011 and June 2019, 69 patients underwent RAVR with self-expandable sutureless aortic bioprostheses at 22 international cardiac centers.

RESULTS

Overall mortality was 2.9% with a predicted logistic EuroSCORE II of 10.7%. Indications for RAVR were structural valve dysfunction (84.1%) and infective prosthetic endocarditis (15.9%) and were performed in patients with previously implanted bioprostheses (79.7%), mechanical valves (15.9%), and transcatheter valves (4.3%). Minimally invasive approach was performed in 15.9% of patients. Rate of stroke was 1.4% and rate of early valve-related reintervention was 1.4%. Overall survival rate at 1 and 5 years was 97% and 91%, respectively. No major paravalvular leak occurred. Rate of pacemaker implantation was 5.8% and 0.9% per patient-year early and at follow-up, respectively. The mean transvalvular gradient at 1-year and 5-year follow-up was 10.5 mm Hg and 11.5 mm Hg with a median effective orifice area of 1.8 cm²and 1.8 cm², respectively.

CONCLUSIONS

RAVR with sutureless valves is a safe and effective approach and provides excellent clinical and hemodynamic results up to 5 years.

A new technique that prevents paravalvular leakage after aortic valve replacement using a rapid-deployment valve system

BACKGROUND

We report our 1-year single-center experience of a new technique of aortic valve replacement using a rapid-deployment valve (RD-AVR) to avoid postoperative complications. We also report the unexpected pitfalls and handling techniques that we have seen in past cases.

METHODS

We performed aortic valve replacement on 38 patients between May 2019 and April 2020. Their mean age was 74 years. The primary outcomes were in-hospital mortality and short-term results during a 1-year follow-up period, while the secondary outcomes were related to prosthetic valve function, especially paravalvular leakage (PVL). We further analyzed the relationship between the new technique and its outcomes.

RESULTS

The mean operative time was 196 min. There were no in-hospital deaths, and the mean duration of postoperative hospital stay was 11.8 days. Valvular measurements using three-dimensional computed tomography were larger and more accurate than those measured using ultrasonic echocardiography. Postoperative RD-AVR prosthetic valve function was excellent. However, PVL occurred in four cases 1 week and 1 year postoperatively and regurgitation did not improve. A gap associated with PVL was identified below the right-noncoronary commissure. To prevent PVL, we additionally stitched this gap in the later 18 cases; there was no case of PVL and no new pacemaker implantation in these cases.

CONCLUSIONS

PVL is more likely to occur if there is a gap below the R-N commissure, especially in cases with a large annulus; therefore, applying an additional stitch to the R-N commissure is extremely useful.

Fabrication and in-vitro characterization of a polymeric aortic valve for minimally invasive valve replacement

The valve replacement therapy is the standard treatment for severe heart valve diseases. Nowadays, two types of commercial prosthesis are available: mechanical and biological, but both of them have severe limitations. Moreover, alternative therapeutic approach for valve replacement, based on minimally invasive techniques (MIAVR), motivates the search for new valve materials. In this study a polyurethane-based self-expandable tri-leaflets heart valve compatible with MIAVR procedure is proposed. The device is based on the development, fabrication and characterization of three different elements: the leaflets, the polymeric stent for supporting the leaflets, and the external metallic stent for anchoring the valve to the native aortic root. The polymeric stent and the valve leaflets were fabricated using a thermoplastic silicone-polycarbonate-urethane using 3D printing and spray technology while the external metallic stent was made in nickel titanium (Nitinol) to obtain a self-expandable valve after the crimping process. The three elements were assembled in the completed device and tested by crimping, fatigue and fluid-dynamic test. The novel polymeric valve proposed showed promising results about valve crimping capabilities, durability and fluid dynamic performances. This approach could offer advantages such as low cost and to produce a tailor-made device basing on patient's imaging data. Moreover, the selected biomaterial offers the potential to have a device that could need of permanent anticoagulation and lack of calcification.

Sutureless and rapid deployment valves: implantation technique from A to Z-the INTUITY Elite valve

In the last two decades, sutureless (Perceval, Livanova PLC, London, UK) and rapid deployment (INTUITY Elite, Edwards Lifesciences, Irvine, CA, USA) valves were introduced to the market as an innovative alternative to traditional valves for patients needing aortic valve replacement (AVR). These devices have been used and studied extensively across these fifteen years, and have proven to be a valid alternative treatment option compared to sutured biological valves, particularly helpful in minimally invasive cardiac surgery, and an almost curative treatment to patients with intermediate to high surgical risk, filling the gap between transcatheter and traditional AVR. However, both sutureless and rapid deployment valves require special steps for implantation, and also a learning curve. Proper specific training to all surgical team members is required as mandatory by the manufacturers. The aim of this review article is to provide cardiac surgeons with a thorough guide on the implantation technique from A to Z, for each of these two prosthetic devices. In this second part of our review article, we will focus on the INTUITY Elite valve.

Aortic valve replacement using stented or sutureless/rapid deployment prosthesis via either full-sternotomy or a minimally invasive approach: a network meta-analysis

Background

New technologies such as sutureless or rapid deployment prosthetic valves and access via minimally invasive incisions offer alternatives to traditional full-sternotomy aortic valve replacement (SAVR). However, a comprehensive comparison of these surgical techniques along with alternative valve prosthesis has not been completed.

Methods

Electronic databases were searched for studies comparing outcomes for SAVR, minimally invasive AVR (MiAVR), sutureless/rapid-deployment AVR (SuAVR) via full-sternotomy, or minimally invasive SuAVR (MiSuAVR) from their inception until September 2018. Early postoperative outcomes and follow-up data were included in a Bayesian network meta-analysis.

Results

Twenty-three studies with 8,718 patients were identified. Compared with standard SAVR, SuAVR had significantly lower incidence of postoperative AF [odds ratio (OR) 0.33, 95% confidence interval (CI): 0.14-0.79, P=0.013] and MiSuAVR greater requirement for postoperative permanent pacemaker (OR 2.27, 95% CI: 1.25-4.14, P=0.008). All sutureless/rapid-deployment procedures had reduced cardiopulmonary bypass and cross-clamp times, by a mean of 25.9 and 25.0 min, respectively. Hospital length of stay (LOS), but not intensive care LOS, was reduced for all groups (MiAVR -1.53 days, MiSuAVR -2.79 days, and SuAVR 3.37 days). A signal towards reduced early mortality, wound infections, and acute kidney injury was noted in both sutureless/rapid-deployment and minimally invasive techniques but did not achieve significance. Sutureless/rapid-deployment procedures had favourable survival and freedom from valve related reoperation, however follow-up times were short and demonstrated significant heterogeneity between intervention groups.

Conclusions

Minimally invasive and sutureless techniques demonstrate equivalent early postoperative outcomes to SAVR and may reduce ventilation time, hospital LOS and postoperative atrial fibrillation (POAF) burden.

Sutureless and rapid deployment valves: implantation technique from A to Z-the Perceval valve

In the last two decades, sutureless (Perceval, LivaNova PLC, London, UK) and rapid deployment valves (RD) (Intuity, Edwards Lifesciences, Irvine, CA, USA) were introduced to the market as an innovative alternative to traditional valves for patients requiring an aortic valve replacement (AVR). These devices have been studied extensively and in use across the last fifteen years. They have proven to not only demonstrate comparable results with conventional sutured biological valves-particularly helpful in minimally invasive cardiac surgery-but also provide an almost curative treatment to patients with intermediate-to-high surgical risk, filling the gap between transcatheter aortic valve implantation (TAVI) and traditional AVR. However, both sutureless and RD valves require special steps for implantation, resulting in a learning curve. Specific training for all surgical team members is mandatory, as recommended by the manufacturers. The aim of this review article is therefore to provide cardiac surgeons with a thorough guide on the implantation technique for each of these two prosthetic devices, from A to Z. In this first article, we will start by focusing on Perceval.

Recent advances in aortic valve replacement

Aortic valve replacement has stood the test of time but is no longer an operation that is exclusively approached through a median sternotomy using only sutured prostheses. Currently, surgical aortic valve replacement can be performed through a number of minimally invasive approaches employing conventional mechanical or bioprostheses as well as sutureless valves. In either case, the direct surgical access allows inspection of the valve, complete excision of the diseased leaflets, and debridement of the annulus in a controlled and thorough manner under visual control. It can be employed to treat aortic valve pathologies of all natures and aetiologies. When compared with transcatheter valves in patients with a high or intermediate preoperative predictive risk, conventional surgery has not been shown to be inferior to transcatheter valve implants. As our understanding of sutureless valves and their applicability to minimally invasive surgery advances, the invasiveness and trauma of surgery can be reduced and outcomes can improve. This warrants further comparative trials comparing sutureless and transcatheter valves.

Video assisted right mini-thoracotomy for aortic valve replacement

Aortic valve replacement through minimally invasive access is increasing. These procedures have several advantages over conventional sternotomy including decreased intensive care unit and hospital length of stay and decreased ventilation time. The right anterior mini-thoracotomy (RAM) approach is potentially attractive in that it completely spares the sternum leading to improved cosmesis, reduced blood loss, and improved patient satisfaction. However, this approach is underutilized due to anticipated technical challenges including difficulty with visualization and annular suture placement. We employ a camera and automated suturing technology for supra-annular valve implant. A RAM is performed via a 5 cm incision in the right second intercostal space with a camera port placed lateral to the incision. Peripheral venous cannulation is performed along with central arterial cannulation. Aortic cross clamp is placed through a 5 mm incision in the third interspace anterior to mid axillary line. Histidine tryptophan ketoglutarate (HTK) cardioplegia is administered. After aortic leaflet removal, annular and prosthetic sutures are placed with shafted instruments or with automated suturing technology. Aortic valve replacement can be performed safely through a RAM. The use of a camera and automated suturing technology facilitates this procedure, potentially enabling more surgeons to offer this less invasive approach to patients.

Review of minimal access versus transcatheter aortic valve replacement for patients with severe aortic stenosis

Transcatheter aortic valve replacement (TAVR) and minimally invasive aortic valve replacement (miniAVR) have become alternatives to surgical aortic valve replacement via median sternotomy (SAVR) to treat severe aortic stenosis (AS). Despite increased interest and utilization, few studies have directly compared TAVR and miniAVR. A review of the current literature shows TAVR to be an indispensable tool for inoperable, high-risk, and perhaps intermediate-risk patients with severe AS. However, it is associated with a number of deleterious perioperative outcomes, such as valvular regurgitation and vascular complications. MiniAVR is associated with decreased intensive care unit (ICU) and hospital length of stay, a lower incidence of blood transfusions, decreased ventilation time, and improved cosmetic results. MiniAVR maintains potential advantages over SAVR, including the implantation of a durable prosthesis and low rates of perioperative myocardial infarction and paravalvular leak. It is associated with longer aortic cross clamp and cardiopulmonary bypass (CPB) times; however, the use of sutureless valve implants can circumvent this. Studies comparing TAVR and miniAVR demonstrate decreased postoperative mortality, valvular regurgitation, and incidence of stroke in the miniAVR cohorts. Few studies currently exist comparing TAVR and miniAVR, as it is hard to compare the typically low-risk miniAVR versus high-risk TAVR patient populations. It is clear that both strategies will be cornerstones in the modern AVR era, but the situations in which to apply each strategy have not yet been clearly delineated. This highlights the need for surgeons to adopt these minimally invasive techniques. We believe there is a compelling role for miniAVR in low- and intermediate-risk patients, but due to the paucity of data, neither TAVR nor miniAVR should be discounted before a randomized, risk-stratified trial is performed. More studies are needed to compare TAVR and miniAVR in low- and intermediate-risk patients.

Minimally invasive aortic valve replacement in high risk patient groups

Minimally invasive aortic valve replacement (AVR) aims to preserve the sternal integrity and improve postoperative outcomes. In low risk patients, this technique can be achieved with comparable mortality to the conventional approach and there is evidence of possible reduction in intensive care and hospital length of stay, transfusion requirement, renal dysfunction, improved respiratory function and increased patient satisfaction. In this review, we aim to asses if these benefits can be transferred to the high risk patient groups. We therefore, discuss the available evidence for the following high risk groups: elderly patients, re-operative surgery, poor lung function, pulmonary hypertension, obesity, concomitant procedures and high risk score cohorts.