Minimally invasive versus conventional aortic valve operations: a prospective study in 120 patients

Early Outcomes of Minimally Invasive Right Anterior Thoracotomy vs. Median Full Sternotomy in Isolated Aortic Valve Replacement: A Propensity Score Analysis

INTRODUCTION

This study aimed to compare the early postoperative outcomes of right anterior thoracotomy minimally invasive aortic valve replacement (RAT-MIAVR) surgery with those of median full sternotomy aortic valve replacement (MFS-AVR) approach with the goal of identifying potential benefits or drawbacks of each technique.

METHODS

This retrospective, observational, cohort study included 476 patients who underwent RAT-MIAVR or MFS-AVR in our hospital from January 2015 to January 2023. Of these, 107 patients (22.5%) underwent RAT-MIAVR, and 369 patients (77.5%) underwent MFS-AVR. Propensity score matching was used to minimize selection bias, resulting in 95 patients per group for analysis.

RESULTS

After propensity matching, two groups were comparable in preoperative characteristics. RAT-MIAVR group showed longer cardiopulmonary bypass time (130.24 ± 31.15 vs. 117.75 ± 36.29 minutes, P=0.012), aortic cross-clamping time (76.44 ± 18.00 vs. 68.49 ± 19.64 minutes, P=0.004), and longer operative time than MFS-AVR group (358.47 ± 67.11 minutes vs. 322.42 ± 63.84 minutes, P=0.000). RAT-MIAVR was associated with decreased hospitalization time after surgery, lower postoperative blood loss and drainage fluid, a reduced incidence of mediastinitis, increased left ventricular ejection fraction, and lower pacemaker use compared to MFS-AVR. However, there was no significant difference in the incidence of major complications and in-hospital mortality between the two groups.

CONCLUSION

RAT-MIAVR is a feasible and safe alternative procedure to MFS-AVR, with comparable in-hospital mortality and early follow-up. This minimally invasive approach may be a suitable option for patients requiring isolated aortic valve replacement.

Limited versus full sternotomy for aortic valve replacement

BACKGROUND

Aortic valve disease is a common condition easily treatable with cardiac surgery. This is conventionally performed by opening the sternum ('median sternotomy') and replacing the valve under cardiopulmonary bypass. Median sternotomy is well tolerated, but as less invasive options become available, the efficacy of limited incisions has been called into question. In particular, the effects of reducing the visibility and surgical access have raised safety concerns with regard to the placement of cannulae, venting of the heart, epicardial wire placement, and de-airing of the heart at the end of the procedure. These difficulties may increase operating times, affecting outcome. The benefits of smaller incisions are thought to include decreased pain; improved respiratory mechanics; reductions in wound infections, bleeding, and need for transfusion; shorter intensive care stay; better cosmesis; and a quicker return to normal activity. This is an update of a Cochrane review first published in 2017, with seven new studies.

OBJECTIVES

To assess the effects of minimally invasive aortic valve replacement via a limited sternotomy versus conventional aortic valve replacement via median sternotomy in people with aortic valve disease requiring surgical replacement.

SEARCH METHODS

We performed searches of CENTRAL, MEDLINE and Embase from inception to August 2021, with no language limitations. We also searched two clinical trials registries and manufacturers' websites. We reviewed references of primary studies to identify any further studies of relevance.

SELECTION CRITERIA

We included randomised controlled trials comparing aortic valve replacement via a median sternotomy versus aortic valve replacement via a limited sternotomy. We excluded trials that performed other minimally invasive incisions such as mini-thoracotomies, port access, transapical, transfemoral or robotic procedures. Although some well-conducted prospective and retrospective case-control and cohort studies exist, these were not included in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial papers to extract data, assess quality, and identify risk of bias. A third review author provided arbitration where required. We determined the certainty of evidence using the GRADE methodology and summarised results of patient-relevant outcomes in a summary of findings table.

MAIN RESULTS

The review included 14 trials with 1395 participants. Most studies had at least two domains at high risk of bias. We analysed 14 outcomes investigating the effects of minimally invasive limited upper hemi-sternotomy on aortic valve replacement as compared to surgery performed via full median sternotomy. Upper hemi-sternotomy may have little to no effect on mortality versus full median sternotomy (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.45 to 1.94; 10 studies, 985 participants; low-certainty evidence). Upper hemi-sternotomy for aortic valve replacement may increase cardiopulmonary bypass time slightly, although the evidence is very uncertain (mean difference (MD) 10.63 minutes, 95% CI 3.39 to 17.88; 10 studies, 1043 participants; very low-certainty evidence) and may increase aortic cross-clamp time slightly (MD 6.07 minutes, 95% CI 0.79 to 11.35; 12 studies, 1235 participants; very low-certainty evidence), although the evidence is very uncertain. Most studies had at least two domains at high risk of bias. Postoperative blood loss was probably lower in the upper hemi-sternotomy group (MD -153 mL, 95% CI -246 to -60; 8 studies, 767 participants; moderate-certainty evidence). Low-certainty evidence suggested that there may be no change in pain scores by upper hemi-sternotomy (standardised mean difference (SMD) -0.19, 95% CI -0.43 to 0.04; 5 studies, 649 participants). Upper hemi-sternotomy may result in little to no difference in quality of life (MD 0.03 higher, 95% CI 0 to 0.06 higher; 4 studies, 624 participants; low-certainty evidence). Two studies reporting index admission costs concluded that limited sternotomy may be more costly at index admission in the UK National Health Service (MD 1190 GBP more, 95% CI 420 GBP to 1970 GBP, 2 studies, 492 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

The evidence was of very low to moderate certainty. Sample sizes were small and underpowered to demonstrate differences in some outcomes. Clinical heterogeneity was also noted. Considering these limitations, there may be little to no effect on mortality. Differences in extracorporeal support times are uncertain, comparing upper hemi-sternotomy to full sternotomy for aortic valve replacement. Before widespread adoption of the minimally invasive approach can be recommended, there is a need for a well-designed and adequately powered prospective randomised controlled trial. Such a study would benefit from also performing a robust cost analysis. Growing patient preference for minimally invasive techniques merits thorough quality of life analyses to be included as end points, as well as quantitative measures of physiological reserve.

Minimal Access Aortic Valve Surgery

Minimally invasive approaches to the aortic valve have been described since 1993, with great hopes that they would become universal and facilitate day-case cardiac surgery. The literature has shown that these procedures can be undertaken with equivalent mortality rates, similar operative times, comparable costs, and some benefits regarding hospital length of stay. The competing efforts of transcatheter aortic valve implantation for these same outcomes have provided an excellent range of treatment options for patients from cardiology teams. We describe the current state of the art, including technical considerations, caveats, and complications of minimal access aortic surgery and predict future directions in this space.

Conventional Versus Minimally Invasive Aortic Valve Replacement Surgery: A Systematic Review, Meta-Analysis, and Meta-Regression

Objective: To assess the potential benefits of minimally invasive aortic valve replacement (MIAVR) compared with conventional AVR (CAVR) by examining short-term outcomes. Methods: A systematic search identified randomized trials comparing MIAVR with CAVR. To assess study limitations and quality of evidence, we used the Cochrane Risk of Bias tool and GRADE and performed random-effects meta-analysis. We used meta-regression and sensitivity analysis to explore reasons for diversity. Results: Thirteen studies (1,303 patients) were included. For the comparison of MIAVR and CAVR, the risk of bias was judged low or unclear and the quality of evidence ranged from very low to moderate. No significant difference was observed in mortality, stroke, acute kidney failure, infectious outcomes, cardiac events, intubation time, intensive care unit stay, reoperation for bleeding, and blood transfusions. Blood loss (mean difference [MD] = -130.58 mL, 95% confidence interval [CI] = -216.34 to -44.82, I² = 89%) and hospital stay (MD = -0.93 days, 95% CI = -1.62 to -0.23, I² = 81%) were lower with MIAVR. There were shorter aortic cross-clamp (MD = 5.99 min, 95% CI = 0.99 to 10.98, I² = 93%) and cardiopulmonary bypass (CPB) times (MD = 7.75 min, 95% CI = 0.27 to 15.24, I² = 94%) in the CAVR group. In meta-regression analysis, we found that age was the variable with the greatest influence on heterogeneity. Conclusions: MIAVR seems to be an excellent alternative to CAVR, reducing hospital stay and incidence of hemorrhagic events. Despite significantly greater aortic cross-clamp and CPB times with MIAVR, this did not translate into adverse effects, with no changes in the results found with CAVR.

Minimally invasive and full sternotomy in aortic valve replacement: a comparative early operative outcomes

Introduction

aortic valve replacement is usually performed through a median full sternotomy (MFS) in our department. Minimally invasive aortic valve replacement (MIAVR) has been recently adopted as a new approach. According to the literature, the superiority of MIAVR is controversial. In this study we report early post-operative outcomes in MIAVR compared with MFS access with reference to blood Loss, wound infections, post-operative recovery, morbidity and mortality.

Methods

this study was a prospective data collection from 36 consecutive patients undergoing isolated valve replacement. Two population study was identified, MIAVR group (group I n=18) and MFS group (group II n=18). Patients´ data were collected and analyzed using IBM SPSS statistics 21 software and Khi2 test has been used to compare the variables. The study variables are presented as numbers, percentage, median with interquartile range. Pre-operative planning was performed so that to obtain similar characteristics.

Results

in group I, upper mini-sternotomy was used in 12 patients and right mini-thoracotomy in 6 patients. There was no difference in term of mortality and morbidity. MIAVR was associated with longer CPB time (93.25 (58-161) vs 131 (75-215) mins, P=0.047) with no significant difference in term of ACC time (81 (33-162) vs 58.8 (59-102) mins P=0.158). MIAVR´ Patients had likely lower incidence of red blood cells transfusion (16.7 vs 52.3%) without significant difference about post-operative haemoglobin (P = 0,330). Patients in group I had shorter ventilation time (2.35 (1-12) vs 9.3 (1-48) hours P < 0.01), shorter ICU stay (2.44 (1-8) vs 4.25 (1-9) days, P = 0,024). The length of hospital stay was shorter, 6.5 (5-9) days in group I vs 7.4 (6-11), P=0.0274. Length of chest tube stay was shorter in group I (mean 1.53 vs 2.4 days, P=0,033). Wound infections were not found in both groups.

Conclusion

minimally invasive aortic valve replacement is associated with less blood loss, faster post-operative recovery faster post-operative recovery but increase operation time.

Expertise-based design in surgical trials: a narrative review

Randomized controlled trials (RCTs) are the most robust study design for evaluating the safety and efficacy of a therapeutic intervention. However, their internal validity are at risk when evaluating surgical interventions. This review summarizes existing expertise- based trials in surgery and related methodological concepts to guide surgeons performing this work. We provide caseloads required to reach the learning curve for various surgical interventions and report criteria for expertise from published and unpublished expertise-based trials. In addition, we review design and implementation concepts of expertise-based trials, including recruitment of surgeons, crossover, ethics, generalizability, sample size and definitions for learning curve. Several RCTs have used an expertise-based design. We found that the majority of definitions used for expertise were vague, heterogeneous, and inconsistent across trials evaluating the same surgical intervention. Statistical methods exist to adjust for the learning curve; however, there is limited guidance. We developed the following criteria for surgical expertise for future trials: 1) decide on the proxy to be used for the learning curve, and 2) assess eligible surgeons by comparing their performance to the previously defined expertise criteria.

Comparative Evaluation of the Incidence of Postoperative Pulmonary Complications After Minimally Invasive Valve Surgery vs. Full Sternotomy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials and Propensity Score-Matched Studies

Background: Postoperative pulmonary complications remain a leading cause of increased morbidity, mortality, longer hospital stays, and increased costs after cardiac surgery; therefore, our study aims to analyze whether minimally invasive valve surgery (MIVS) for both aortic and mitral valves can improve pulmonary function and reduce the incidence of postoperative pulmonary complications when compared with the full median sternotomy (FS) approach. Methods: A comprehensive systematic literature research was performed for studies comparing MIVS and FS up to February 2021. Randomized controlled trials (RCTs) and propensity score-matching (PSM) studies comparing early respiratory function and pulmonary complications after MIVS and FS were extracted and analyzed. Secondary outcomes included intra- and postoperative outcomes. Results: A total of 10,194 patients from 30 studies (6 RCTs and 24 PSM studies) were analyzed. Early mortality differed significantly between the groups (MIVS 1.2 vs. FS 1.9%; p = 0.005). Compared with FS, MIVS significantly lowered the incidence of postoperative pulmonary complications (odds ratio 0.79, 95% confidence interval [0.67, 0.93]; p = 0.004) and improved early postoperative respiratory function status (mean difference -24.83 [-29.90, -19.76]; p < 0.00001). Blood transfusion amount was significantly lower after MIVS (p < 0.02), whereas cardiopulmonary bypass time and aortic cross-clamp time were significantly longer after MIVS (p < 0.00001). Conclusions: Our study showed that minimally invasive valve surgery decreases the incidence of postoperative pulmonary complications and improves postoperative respiratory function status.

J-ministernotomy for aortic valve replacement: a retrospective cohort study

Background

The advantage of minimally invasive sternotomy (MS) over full sternotomy (FS) for isolated aortic valve replacement (AVR) is still controversial. We aimed to examine if J-shaped MS is a safe alternative to FS in patients undergoing primary isolated AVR. This study is a retrospective and restricted cohort study that included 137 patients who had primary isolated AVR from February 2013 to June 2015. Patients with previous cardiac operations, low ejection fraction (< 40%), infective endocarditis, EuroSCORE II predicted mortality > 10%, and patients who had inverted T or inverted C-MS or right anterior thoracotomy were excluded. Patients were grouped into the FS group (n=65) and MS group (n=72). Preoperative variables were comparable in both groups. The outcome was studied, balancing the groups by propensity score matching.

Results

Seven (9%) patients in the MS group were converted to FS. Cardiopulmonary bypass (98.5 ± 29.3 vs. 82.1 ± 13.95 min; p ≤ 0.001) and ischemic times (69.1 ± 23.8 vs. 59.6 ± 12.2 min; p = 0.001) were longer in MS. The MS group had a shorter duration of mechanical ventilation (10.1 ± 11.58 vs. 10.9 ± 6.43 h; p = 0.045), ICU stay (42.74 ± 40.5 vs. 44.9 ± 39.3; p = 0.01), less chest tube drainage (385.3 ± 248.6 vs. 635.9 ± 409.6 ml; p = 0.001), and lower narcotics use (25.14 ± 17.84 vs. 48.23 ± 125.68 mg; p < 0.001). No difference was found in postoperative heart block with permanent pacemaker insertion or atrial fibrillation between groups (p = 0.16 and 0.226, respectively). Stroke, renal failure, and mortality did not differ between the groups. Reintervention-free survival at 1, 3, and 4 years was not significantly different in both groups (p = 0.73).

Conclusion

J-ministernotomy could be a safe alternative to FS in isolated primary AVR. Besides the cosmetic advantage, it could have better clinical outcomes without added risk.

Minimally invasive aortic valve surgery

Since their introduction, it has been demonstrated that minimally invasive aortic valve replacement (MIAVR) approaches are safe and effective for the treatment of aortic valve diseases. To date, the main advantage of these approaches is represented by the reduced surgical trauma, with a subsequent reduced complication rate and faster recovery. This makes such approaches an appealing choice also for frail patients [obese, aged, chronic obstructive pulmonary disease (COPD)]. The standardization of the minimally invasive techniques, together with the implementation of preoperative workup and anesthesiological intra- and post-operative care, led to an amelioration of surgical results and reduction of surgical times. Moreover, the improvement of surgical technology and the introduction of new devices such as sutureless and rapid deployment (SURD) valves, has helped the achievement of comparable results to traditional surgery. However, transcatheter technologies are nowadays more and more important in the treatment of aortic valve disease, also in low risk patients. For this reason surgeons should put new efforts for further reducing the surgical trauma in the future, even taking inspiration from other disciplines. In this review, we aim to present a review of literature evidences regarding minimally invasive treatment of aortic diseases, also reflecting our personal experience with MIAVR techniques. This review could represent a tool for a well-structured patient assessment and preoperative planning, in order to safely carrying out an MIAVR procedure with satisfactory outcomes.

Comparing quality of life and postoperative pain after limited access and conventional aortic valve replacement: Design and rationale of the LImited access aortic valve replacement (LIAR) trial

Background

Surgical aortic valve replacement (SAVR) via limited access approaches (‘mini-AVR’) have proven to be safe alternative for the surgical treatment of aortic valve disease. However, it remains unclear whether these less invasive approaches are associated with improved quality of life and/or reduced postoperative pain when compared to conventional SAVR via full median sternotomy (FMS).

Study design

The LImited access Aortic valve Replacement (LIAR) trial is a single-center, single blind randomized controlled clinical trial comparing 2 arms of 80 patients undergoing limited access SAVR via J-shaped upper hemi-sternotomy (UHS) or conventional SAVR through FMS. In all randomized patients, the diseased native aortic valve is planned to be replaced with a rapid deployment stented bioprosthesis. Patients unwilling or unable to participate in the randomized trial will be treated conventionally via SAVR via FMS and with implantation of a sutured valve prosthesis. These patients will participate in a prospective registry.

Study methods

Primary outcome is improvement in cardiac-specific quality of life, measured by two domains of the Kansas City Cardiomyopathy Questionnaire up to one year after surgery. Secondary outcomes include, but are not limited to: generic quality of life measured with the Short Form-36, postoperative pain, perioperative (technical success rate, operating time) and postoperative outcomes (30-day and one-year mortality), complication rate and hospital length of stay.

Conclusion

The LIAR trial is designed to determine whether a limited access approach for SAVR (‘mini-AVR’) is associated with improved quality of life and/or reduced postoperative pain compared with conventional SAVR through FMS.

The study is registered at ClinicalTrials.gov, number NCT04012060.

Quality of Life After Ministernotomy Versus Full Sternotomy Aortic Valve Replacement

Quality of life and patient satisfaction after ministernotomy have never been compared to conventional full sternotomy in randomized trials. The QUALITY-AVR trial is a single-blind, single-center, independent, randomized clinical trial comparing ministernotomy to full sternotomy in patients with isolated severe aortic stenosis scheduled for elective aortic valve replacement. One hundred patients were randomized in a 1:1 computational fashion. The primary endpoint was a difference between intervention groups of ≥0.10 points in change from baseline quality of life Questionnaire EuroQOL-index, measured at 1, 6, or 12 months. Secondary endpoints were differences in change from other baseline EuroQOL-index utilities, cardiac surgery-specific satisfaction questionnaire (SATISCORE), a combined safety endpoint of 4 major adverse complications at 1 month (all-cause mortality, acute myocardial infarction, neurologic events, and acute renal failure), bleeding through drains within the first 24 hours, intubation time, and other minor endpoints. Clinical follow-up was scheduled at baseline, 1, 6, and 12 months after randomization. Change from baseline mean difference EQ-5D-index was +0.20 points (95% confidence interval 0.10-0.30, P < 0.001) and median difference +0.14 (95% confidence interval 0.06-0.22, P < 0.001), favoring the ministernotomy group at 1 month. Patient satisfaction was also better at 1 month (Satiscore 83 ± 9 vs 77 ± 13 points; P = 0.010). The ministernotomy group had significantly less bleeding in the first 24 hours (299 ± 140 vs 509 ± 251 mL, P = 0.001). Ministernotomy provides a faster recovery with improved quality of life and satisfaction at 1 month compared to full sternotomy.

[Aortic valve replacement via J-shaped partial upper sternotomy: randomized trial, mid-term results]

OBJECTIVE

To evaluate the effectiveness and safety of aortic valve replacement through upper partial J-shaped sternotomy compared to conventional sternotomy.

MATERIAL AND METHODS

There were 240 procedures of isolated aortic valve replacement for the period 2012-2017. According to inclusion criteria, 112 patients were randomized into 2 groups: group I - median sternotomy, group II - upper partial J-shaped sternotomy. Mean age of patients was 56.1±14.3 and 53.1±14.9 years, respectively (p=0.284). Females prevailed in both groups (55.4% vs. 57.1%, p=0.848). Peak pressure gradient on the aortic valve was 106.2±23.9 and 102.8±25.3 mm Hg, respectively (p=0.484).

RESULTS

In-hospital mortality was 1.8% (n=1) in group I (p=0.315). Incidence of postoperative complications (complete atrioventricular blockade, ventricular septal defect) was similar (p=1.0). Mean time cross clamping in I and II groups was 65.5±12.5 and 64.7±13.1 min (p=0.729). Mean follow-up period was 31.6 and 33.5 months, respectively. Kaplan-Meier survival rate was 92.6 and 93.0%, respectively (log-rank test=0,767). Freedom from thromboembolic events was 91.7 and 90% (log-rank test=0.213).

CONCLUSION. U

Pper partial J-shaped sternotomy is safe and effective for aortic valve surgery and characterized by similar outcomes compared to conventional sternotomy.

Right anterior mini-thoracotomy and sutureless valves: the perfect marriage

Background

A minimally invasive approach (MIA) reduces mortality and morbidity in patients referred for aortic valve replacement (AVR). Sutureless technology facilitates a MIA. We describe our experience with the sutureless Perceval (LivaNova, Italy) aortic bioprosthesis through a right anterior mini-thoracotomy (RAMT) approach.

Methods

Between March 2011 and October 2019, 1,049 patients underwent AVR with Perceval bioprosthesis. Five hundred and three patients (48%) were operated through a RAMT approach in the second intercostal space. Considering only isolated AVR (881), 98% of patients were operated with MIA, and Perceval in RAMT approach was performed in 57% of these patients. Eight patients (1.6%) had previously undergone cardiac surgery. The prosthesis sizes implanted were: S (n=91), M (n=154), L (n=218) and XL (n=40). Concomitant procedures were mitral valve surgery (n=6), tricuspid valve repair (n=1), mitral valve repair and tricuspid valve repair (n=1) and miectomy (n=2). Mean age was 78±4 years (range, 65-89 years), 317 patients were female (63%) and EuroSCORE II was 5.9%±8.4%.

Results

The 30-day mortality was 0.8% (4/503). Cardiopulmonary bypass (CPB) and aortic cross-clamp times were 81.6±30.8 and 50.3±24.5 minutes respectively for stand-alone procedures. In two patients, early moderate paravalvular leakage appeared as a result of incomplete expansion of the sutureless valve due to oversizing of the bioprosthesis, requiring reoperations at two and nine postoperative days with sutured aortic bioprosthesis implantation. Permanent pacemaker implantation within the first thirty days was necessary in 26 (5.2%) patients. At the mean follow-up of 4.6 years (range, 1 month to 8.6 years), survival was 96%, freedom from reoperation was 99.2%, and mean transvalvular pressure gradient was 11.9±4.3 mmHg.

Conclusions

AVR with the Perceval bioprosthesis in a RAMT approach is a safe and feasible procedure associated with low mortality and excellent hemodynamic performance. Sutureless technology facilitates a RAMT approach.

Multiple Valve Implantation Through a Minimally Invasive Approach: Comparison of Standard Median Sternotomy and Right Anterior Thoracotomy

BACKGROUND

Following developments in the area of minimally invasive surgery and good, recently published surgical results, the areas in which minimally invasive surgery can be used are beginning to expand. This study aimed to describe experience and show the feasibility and safety of minimally invasive multiple valve implantation with right anterior minithoracotomy (RAT) and compare the outcomes with cases that underwent multiple valve surgery via a standard median sternotomy.

METHODS

The study cohort comprised 52 patients with combined valvular disease who underwent aortic valve replacement and mitral valve replacement or repair, and/or tricuspid valve ring annuloplasty through median sternotomy (control group n=32) or minimally invasive surgery through a RAT (study group n=20) between January 2012 and December 2018 at the current centre. Preoperative evaluation included coronary catheterisation and multisliced computerised tomography in all patients. Postoperative clinical outcomes and haemodynamic performance of heart valves were reviewed.

RESULTS

The mean age of patients was 72.6±7.1 years, and 50% were male. Seventeen (17) patients (32.6%) were in New York Heart Association functional class III or IV. Three (3) patients (7.6%) had third-degree atrioventricular block requiring permanent pacemaker implantation. Mean follow-up was 21±3.9 months (maximum 26 months). No major paravalvular leakage occurred, and there was no postoperative valve migration in either group. Non-valve-related deaths occurred in five patients during follow-up.

CONCLUSION

This study showed that minimally invasive multiple valve implantation is a technically feasible and safe procedure with acceptable surgical outcomes and similar postoperative quality when compared with median sternotomy.

Minimally invasive aortic valve replacement with central cannulation: A cost-benefit analysis in a developing country

Background

Minimally-invasive approaches to aortic valve replacement (MIAVR) are technically and logistically demanding. However, few centers have started using these approaches with standard equipment because of the limited resources. We sought to report intra- and postoperative clinical outcomes and address health resource utilization after MIAVR.

Results

A total of 102 eligible patients who had aortic valve replacement were enrolled in a prospective, multicenter cohort study conducted from June 2015 to December 2017. Fifty patients underwent aortic valve surgery via upper inverted T-shaped hemi-sternotomy (MS), and 52 patients were operated using full sternotomy (FS) in two centers in a developing country. Central cannulation was performed in all cases. Major adverse cardiac events, pain, and wound complications were compared. A cost analysis was performed, and exposure and feasibility for cannulation were assessed. The mean length of MS skin incision was 5.82 ± 0.67 cm. Cumulative cross-clamp time was insignificant between both groups (91.87 ± 34.41 versus 94.91 ± 33.96 min; p = 0.66). MS exhibited shorter ventilation time (6.18 ± 1.86 versus 10.68 ± 12.78 h; p = 0.029) and intensive care stays (33.27 ± 19.75 versus 49.42 ± 47.1 h; p = 0.037). Major adverse cardiac events (MACEs) were compared, and MS group exhibited fewer transfusions (1.18 ± 0.89 versus 1.7 ± 0.97 units; p = 0.002), fewer pulmonary complications (1 (2%) versus 2 (3.8%); p < 0.001), and less sternotomy wound infection (1 (2%) versus 5 (9.6%); p = 0.048). Total operative mortality of 4.46% was recorded (n = 5). Significant cost reduction was recorded favoring MS; central cannulation saved $907.16 and carried a total cost reduction of $580 (9.3%) when compared with the FS approach (p < 0.0001).

Conclusions

With a lack of logistics in developing countries, MIAVR not only has a cosmetic advantage but carries a significant reduction in blood use, respiratory complications, pain, and cost. MIAVR can be feasible, with a rapid learning curve in developing centers.

Does minimal invasive cardiac surgery reduce the incidence of post-operative atrial fibrillation?

Atrial fibrillation (AF) is the most common post-operative complication and tends to be the most common arrhythmia after cardiac surgery. The etiology and risk factors for post-operative AF are poorly understood, but older age, large left atrium, diffuse coronary artery disease, a history of AF paroxysms and in general, pre-existing cardiac conditions that cause restricting and susceptibility towards inflammation have been consistently linked with post-operative atrial fibrillation (POAF). It has been traditionally thought that post-operative AF is transient, well-tolerated, benign to the patient and self-limiting complication of cardiac surgery that was temporary and easily treated. However, recent evidence suggests that POAF may be more "malignant" than previously thought, associated with follow-up mortality and morbidity. Several minimally invasive approaches, including the right parasternal approach, upper and lower mini-sternotomy (MS), V-shaped, Z-shaped, inverse-T, J-, reverse-C and reverse-L partial MS, transverse sternotomy and right mini-thoracotomy, have been developed for cardiac surgery operations since 1993 and have been associated with better outcomes and lower perioperative morbidity compared to full sternotomy (FS). The common goal of several minimally invasive approaches is to reduce invasiveness and surgical trauma. According to a statement from the American Heart Association (AHA), the term "minimally invasive" refers to a small chest wall incision that does not include a FS. This review is aimed to evaluate the use of minimally invasive techniques like mini-sternotomy, mini-thoracotomy and hybrid techniques versus conventional techniques which are used in cardiac surgery and to compare the frequency of post-operative AF and its effect on post-operative complications, morbidity and mortality, after cardiac surgery operations with FS versus cardiac surgery operations with the use of minimally invasive techniques.

Improved Patient Recovery With Minimally Invasive Aortic Valve Surgery: A Propensity-Matched Study

Objective

Despite conflicting evidence available, minimally invasive aortic valve replacement (MIAVR) is increasingly used as an alternative to full sternotomy. We sought to compare early outcomes of aortic valve replacement through a full sternotomy (conventional aortic valve replacement [CAVR]) and upper ministernotomy (MIAVR).

Methods

We analyzed 297 patients having undergone primary, elective, isolated MIAVR or CAVR between January 2014 and June 2018. Following propensity score matching, 120 patients remained in each group.

Results

MIAVR required longer bypass (93 ± 26 vs 81 ± 24 minutes, P < 0.01) and operative times (214 ± 39 vs 182 ± 37 minutes, P < 0.01). However, aortic cross-clamp times were comparable (57 ± 17 vs 54 ± 14 minutes for MIAVR and CAVR, respectively, P = 0.14). MIAVR had less 24-hour blood loss (253 ± 204 vs 323 ± 296 mL, P = 0.03), less red blood cells transfusions [1.4 packs (1.1 o 1.9) vs 2.1 packs (1.8 to 2.7), P = 0.01], and shorter assisted ventilation time (7.1 ± 3.3 vs 9.7 ± 3.8 hours, P < 0.01) when compared to CAVR. These results led to significantly shorter intensive care unit and hospital stays for MIAVR patients (2.5 ± 1.3 vs 3.4 ± 1.1 days, P < 0.01 and 6.9 ± 4.1 vs 8.2 ± 4.8 days, P = 0.03, respectively). Thirty-day mortality and clinical outcomes did not differ significantly among groups.

Conclusions

MIAVR through upper ministernotomy was shown to be as safe and reliable as CAVR. Patient recovery time was improved by shortening mechanical ventilation and reducing blood loss and transfusions. These results may be significant for high-risk patients undergoing aortic valve surgery.

Evolution of Minimally Invasive Surgical Aortic Valve Replacement at a Veterans Affairs Medical Center

OBJECTIVE

The majority of minimally invasive surgical aortic valve replacements (MIAVRs) are performed at high-volume cardiac surgery centers. However, outcomes at lower volume federal facilities are not yet reported in the literature and not captured in the national Society of Thoracic Surgeons (STS) database. Our study objective was to describe the evolution of MIAVR at a Veterans Affairs Medical Center (VAMC).

METHODS

A single-center retrospective cohort study was performed of 114 patients who underwent MIAVR for isolated aortic valvular disease between January 2011 and August 2018. Preoperative STS risk factors were determined and perioperative outcomes were analyzed.

RESULTS

By 2016, 100% of isolated surgical aortic valve replacements were performed as MIAVRs at our VAMC. Introduction of automatic knot-fastening devices, single-shot del Nido cardioplegia, and rapid deployment valves decreased aortic cross-clamp (AXC) times from a median of 96 (interquartile range [IQR]: 84 to 103) to 53 minutes (38 to 61, P < 0.001, Kruskal-Wallis). Thirty-day mortality was 0.9%. Median length of hospital stay was 9 days (7 to 13). Postoperative atrial fibrillation occurred in 54% of patients, stroke occurred in 1.8% of patients, and 7.1% of patients required permanent pacemakers. Transition to rapid deployment valves decreased postoperative mean pressure gradient from median 14 mmHg (10 to 17) to 7 mmHg (4.7 to 10, P < 0.001, Mann-Whitney). At median 1.5-year follow-up echocardiogram, mean gradient was 10.8 mmHg with mild paravalvular leak rate of 1.8%.

CONCLUSIONS

Facilitating technologies decreased operative times during MIAVR adoption at our VAMC. For patients with isolated aortic valve pathology, MIAVR can be performed with low morbidity and mortality at lower volume federal institutions, with outcomes comparable to those reported from higher volume centers.

Minimally invasive surgical aortic valve replacement

Minimally invasive aortic valve replacement (MIAVR) is defined as a surgical aortic valve replacement which involves smaller chest incisions as opposed to full sternotomy. It is performed using cardiopulmonary bypass with cardiac arrest. It benefits from potential advantages of a less invasive procedure. To date, over 14 000 MIAVR have been reported in the literature. Due to heterogeneity of the studies, different surgical techniques and mainly the non-randomised nature of these studies comparing MIAVR with conventional aortic valve replacement, it is difficult to draw definitive conclusions. The two main techniques of MIAVR are mini-sternotomy and right anterior mini-thoracotomy. Both techniques with other less common forms of MIAVR will be discussed in this review. The advantages, disadvantages and surgical pitfalls will be discussed. Some of the advantages include shorter intensive care and hospital stay, reduced perioperative blood loss, less pain, improved respiratory function and cosmesis. The possible disadvantage of longer bypass and cross-clamp times may be counter balanced by the recent sutureless and rapid deployment valves. Despite some of the benefits, MIAVR has not been adopted by a significant proportion of the surgeons possibly related to the learning curve and requirements for re-training. As MIAVR becomes more common, randomised trials comparing this technique with transcatheter aortic valve implantation is warranted. In addition, assessing quality of life including return to work and functional capacity is needed.

The Opportunities and Limitations of Minimally Invasive Cardiac Surgery

BACKGROUND

Over the past two decades, minimally invasive techniques for classic heart valve surgery and isolated bypass surgery have been developed that enable access to the heart via partial sternotomy for most aortic valve procedures and via sternotomy-free mini-thoracotomy for other procedures.

METHODS

We review the current evidence on minimally invasive cardiac surgery on the basis of pertinent randomized studies and database studies retrieved by a selective search in the MEDLINE and PubMed Central databases, as well as by the Google Scholar search engine.

RESULTS

A PubMed search employing the search term "minimally invasive cardiac surgery" yielded nearly 10 000 hits, among which there were 7 prospective, randomized, controlled trials (RCTs) on aortic valve replacement, with a total of 477 patients, and 3 RCTs on mitral valve surgery, with a total of 340 patients. Only limited reports of specified centers are currently available for multiple valvular procedures and multiple coronary artery bypass procedures. The RCTs reveal that the minimally invasive techniques are associated with fewer wound infections and faster mobilization, without any difference in survival. Minimally invasive procedures are technically demanding and have certain anatomical prerequisites, such as appropriate coronary morphology for multiple bypass operations and the position of the aorta in the chest for sternotomy-free aortic valve procedures. The articles reviewed here were presumably affected by selection bias, in that patients in the published studies were preselected, and there may have been negative studies that were not published at all.

CONCLUSION

Specialized surgeons and centers can now carry out many cardiac valvular and bypass operations via minithoracotomy rather than sternotomy. According to current evidence, these minimally invasive techniques yield results that are at least as good as classic open-heart surgery.

Quality of life, satisfaction and outcomes after ministernotomy versus full sternotomy isolated aortic valve replacement (QUALITY-AVR): study protocol for a randomised controlled trial

BACKGROUND

During the last decade, the use of ministernotomy in cardiac surgery has increased. Quality of life and patient satisfaction after ministernotomy have never been compared to conventional full sternotomy in randomised trials. The aim of the study is to determine if this minimally invasive approach improves quality of life, satisfaction and clinical morbimortality outcomes.

METHODS/DESIGN

The QUALITY-AVR trial is a single-blind, single-centre, independent, and pragmatic randomised clinical trial comparing ministernotomy ("J" shaped upper hemisternotomy toward right 4th intercostal space) to full sternotomy in patients with isolated severe aortic stenosis scheduled for elective aortic valve replacement. One hundred patients will be randomised in a 1:1 computational fashion. Sample size was determined for the primary end point with alpha error of 0.05 and with power of 90% in detecting differences between intervention groups of ≥ 0.10 points in change from baseline quality of life Questionnaire EuroQOL-index (EQ-5D-5 L®), measured at 1, 6 or 12 months. Secondary endpoints are: the differences in change from other baseline EQ-5D-5 L® utilities (visual analogue scale, Health Index and Severity Index), cardiac surgery specific satisfaction questionnaire (SATISCORE®), a combined safety endpoint of four major adverse complications at 1 month (all-cause mortality, acute myocardial infarction, neurologic events and acute renal failure), bleeding through drains within the first 24 h, intubation time, postoperative hospital and intensive care unit length of stay, transfusion needs during the first 72 h and 1-year survival rates. Clinical follow up is scheduled at baseline, 1, 6, and 12 months after randomization. All clinical outcomes are recorded following the Valve Academic Research Consortium 2 criteria.

DISCUSSION

The QUALITY-AVR trial aims to test the hypothesis that ministernotomy improves quality of life, satisfaction and clinical outcomes in patients referred for isolated aortic valve replacement. Statistically significant differences favouring ministernotomy could modify the surgical "gold standard" for aortic stenosis surgery, and subsequently the need to change the control group in transcatheter aortic valve implantation trials. Recruitment started on 18 March 2016. In November 2017, 75 patients were enrolled.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT02726087 . Registered on 13 March 2016.

Are Sutureless Aortic Valves Suitable for Severe High-Risk Patients Suffering from Active Infective Aortic Valve Endocarditis?

Background

Sutureless aortic valves were introduced to facilitate minimally invasive aortic valve surgery. Since sutureless aortic valves are a feasible procedure, we evaluated if any benefits could be identified in severe high-risk patients with active infective endocarditis of the aortic valve.

Material/Methods

Between April 2014 and April 2015, a total of 42 patients received a sutureless Perceval^® aortic valve (Sorin Biomedica Cardio Srl, Saluggia, Italy) for different indications. Nine of these patients (median age 71 years, range 47–83 years) suffered from active infective endocarditis, including four patients with prosthetic aortic valve endocarditis. Five patients underwent prior cardiac surgery, including transcatheter aortic valve implantation (TAVI). The median EuroSCORE II was 29.5% (range 16.8–87.7%). Post-operatively, data regarding mortality, operative results, and early operative morbidity were collected.

Results

There were no cases of 30-day mortality. Four patients needed abscess closure with pericardium. Three patients underwent left atrial appendix closure: one left ventricular thrombectomy, one bypass grafting, and one arch replacement. Median aortic cross-clamp and cardiopulmonary bypass time was 35 minutes (range 26–88 minutes) and 52 minutes (range 40–133 minutes), respectively. The median intubation time was 14 hours (range 1–9 hours). In these high-risk patients, no postoperative morbidity was found except for one re-intubation due to extensive delirium and one re-exploration. No pacemaker implantation was needed. Echocardiographic evaluation showed no central or para-valvular regurgitation, and a median discharge mean gradient of 5.5 mm Hg (range 2.5–10.0 mm Hg).

Conclusions

Sutureless aortic valve replacement in very high-risk patients suffering from active infection endocarditis seems to be an option with limited morbidity and appropriate echocardiographic results, however, further studies are needed.

The economic value of rapid deployment aortic valve replacement via full sternotomy

Aim: To compare the economic value of EDWARDS INTUITY Elite™ (EIE) valve system for rapid-deployment aortic valve replacement (RDAVR) in a full sternotomy (FS) approach (EIE-FS-RDAVR) versus FS-AVR using conventional stented bioprosthesis. Data & methods: A simulation model to compare each treatment's 30-day inpatient utilization and complication rates utilized: clinical end points obtained from the TRANSFORM trial patient subset (EIE-FS-RDAVR) and a best evidence review of the published literature (FS-AVR); and costs from the Premier database and published literature. Results: EIE-FS-RDAVR costs $800 less than FS-AVR per surgery episode attributable to lowered complication rates and utilization. Combined with the lower mortality, EIE-FS-RDAVR was a superior (dominant) technology versus FS-AVR. Conclusion: This preliminary investigation of EIE-FS-RDAVR versus conventional FS-AVR found the EIE valve offered superior economic value over a 30-day period. Real-world analyses with additional long-term follow-up are needed to evaluate if this result can be replicated over a longer timeframe.

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.

Limited versus full sternotomy for aortic valve replacement

BACKGROUND

Aortic valve disease is a common condition that is easily treatable with cardiac surgery. This is conventionally performed by opening the sternum longitudinally down the centre ("median sternotomy") and replacing the valve under cardiopulmonary bypass. Median sternotomy is generally well tolerated, but as less invasive options have become available, the efficacy of limited incisions has been called into question. In particular, the effects of reducing the visibility and surgical access has raised safety concerns with regards to the placement of cannulae, venting of the heart, epicardial wire placement, and de-airing of the heart at the end of the procedure. These difficulties may increase operating times, affecting outcome. The benefits of smaller incisions are thought to include decreased pain; improved respiratory mechanics; reductions in wound infections, bleeding, and need for transfusion; shorter intensive care stay; better cosmesis; and a quicker return to normal activity.

OBJECTIVES

To assess the effects of minimally invasive aortic valve replacement via a limited sternotomy versus conventional aortic valve replacement via median sternotomy in people with aortic valve disease requiring surgical replacement.

SEARCH METHODS

We performed searches of CENTRAL, MEDLINE, Embase, clinical trials registries, and manufacturers' websites from inception to July 2016, with no language limitations. We reviewed references of identified papers to identify any further studies of relevance.

SELECTION CRITERIA

Randomised controlled trials comparing aortic valve replacement via a median sternotomy versus aortic valve replacement via a limited sternotomy. We excluded trials that performed other minimally invasive incisions such as mini-thoracotomies, port access, trans-apical, trans-femoral or robotic procedures. Although some well-conducted prospective and retrospective case-control and cohort studies exist, these were not included in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial papers to extract data, assess quality, and identify risk of bias. A third review author provided arbitration where required. The quality of evidence was determined using the GRADE methodology and results of patient-relevant outcomes were summarised in a 'Summary of findings' table.

MAIN RESULTS

The review included seven trials with 511 participants. These included adults from centres in Austria, Spain, Italy, Germany, France, and Egypt. We performed 12 comparisons investigating the effects of minimally invasive limited upper hemi-sternotomy on aortic valve replacement as compared to surgery performed via full median sternotomy.There was no evidence of any effect of upper hemi-sternotomy on mortality versus full median sternotomy (risk ratio (RR) 1.01, 95% confidence interval (CI) 0.36 to 2.82; participants = 511; studies = 7; moderate quality). There was no evidence of an increase in cardiopulmonary bypass time with aortic valve replacement performed via an upper hemi-sternotomy (mean difference (MD) 3.02 minutes, 95% CI -4.10 to 10.14; participants = 311; studies = 5; low quality). There was no evidence of an increase in aortic cross-clamp time (MD 0.95 minutes, 95% CI -3.45 to 5.35; participants = 391; studies = 6; low quality). None of the included studies reported major adverse cardiac and cerebrovascular events as a composite end point.There was no evidence of an effect on length of hospital stay through limited hemi-sternotomy (MD -1.31 days, 95% CI -2.63 to 0.01; participants = 297; studies = 5; I2 = 89%; very low quality). Postoperative blood loss was lower in the upper hemi-sternotomy group (MD -158.00 mL, 95% CI -303.24 to -12.76; participants = 297; studies = 5; moderate quality). The evidence did not support a reduction in deep sternal wound infections (RR 0.71, 95% CI 0.22 to 2.30; participants = 511; studies = 7; moderate quality) or re-exploration (RR 1.01, 95% CI 0.48 to 2.13; participants = 511; studies = 7; moderate quality). There was no change in pain scores by upper hemi-sternotomy (standardised mean difference (SMD) -0.33, 95% CI -0.85 to 0.20; participants = 197; studies = 3; I2 = 70%; very low quality), but there was a small increase in postoperative pulmonary function tests with minimally invasive limited sternotomy (MD 1.98 % predicted FEV1, 95% CI 0.62 to 3.33; participants = 257; studies = 4; I2 = 28%; low quality). There was a small reduction in length of intensive care unit stays as a result of the minimally invasive upper hemi-sternotomy (MD -0.57 days, 95% CI -0.93 to -0.20; participants = 297; studies = 5; low quality). Postoperative atrial fibrillation was not reduced with minimally invasive aortic valve replacement through limited compared to full sternotomy (RR 0.60, 95% CI 0.07 to 4.89; participants = 240; studies = 3; moderate quality), neither were postoperative ventilation times (MD -1.12 hours, 95% CI -3.43 to 1.19; participants = 297; studies = 5; low quality). None of the included studies reported cost analyses.

AUTHORS' CONCLUSIONS

The evidence in this review was assessed as generally low to moderate quality. The study sample sizes were small and underpowered to demonstrate differences in outcomes with low event rates. Clinical heterogeneity both between and within studies is a relatively fixed feature of surgical trials, and this also contributed to the need for caution in interpreting results.Considering these limitations, there was uncertainty of the effect on mortality or extracorporeal support times with upper hemi-sternotomy for aortic valve replacement compared to full median sternotomy. The evidence to support a reduction in total hospital length of stay or intensive care stay was low in quality. There was also uncertainty of any difference in the rates of other, secondary outcome measures or adverse events with minimally invasive limited sternotomy approaches to aortic valve replacement.There appears to be uncertainty between minimally invasive aortic valve replacement via upper hemi-sternotomy and conventional aortic valve replacement via a full median sternotomy. Before widespread adoption of the minimally invasive approach can be recommended, there is a need for a well-designed and adequately powered prospective randomised controlled trial. Such a study would benefit from performing a robust cost analysis. Growing patient preference for minimally invasive techniques merits thorough quality-of-life analyses to be included as end points, as well as quantitative measures of physiological reserve.

Assessment Based on EuroSCORE of Ministernotomy for Aortic Valve Replacement

To assess the advantages of a ministernotomy over a standard sternotomy for aortic valve replacement, 191 patients were classified as low-, medium-, and high-risk by EuroSCORE. A ministernotomy was carried out in 100 patients, and a standard sternotomy was used in 91. Among low-risk patients, those who had a ministernotomy showed a marginal increase in atrial fibrillation. Of the medium-risk patients, those who had a sternotomy had significantly more atrial fibrillation and slightly more general infections. In the high-risk subgroup, significantly more atrial fibrillation was observed in the sternotomy group, and more neurologic events were observed in the ministernotomy group; the difference became nonsignificant when only severe events were considered. There was a significant benefit in terms of rhythm disturbances in medium- and high-risk patients who underwent a ministernotomy compared to those who had a full sternotomy. Mortality, duration of intensive care, and hospital stay were not influenced by the operative method.

Minimally Invasive Aortic Valve Replacement in Left Ventricular Dysfunction

The safety and benefit of minimally invasive aortic valve replacement in patients with left ventricular dysfunction has not been well investigated. We conducted a retrospective review of 140 patients with ejection fraction ≤ 40% who underwent isolated aortic valve replacement between July 1996 and March 2005. Aortic valve replacement was performed via an upper hemisternotomy in 73 patients and via a full sternotomy in 67. Two matched cohorts of 41 patients each were constructed using propensity score analysis, and the outcomes were compared. There was no significant difference in operative mortality (hemisternotomy, 2.4% vs 4.8% for full sternotomy), incidence of postoperative complications, blood transfusion requirement, length of hospital stay, or discharge to home rates. Aortic valve replacement via an upper hemisternotomy can be performed safely, even in patients with left ventricular dysfunction, with morbidity and mortality outcomes similar to those of a full sternotomy.

Influence of body mass index on outcomes after minimal-access aortic valve replacement through a J-shaped partial upper sternotomy

Background

Minimal-access aortic valve replacement (MAAVR) may reduce post-operative blood loss and transfusion requirements, decrease post-operative pain, shorten length stay and enhance cosmesis. This may be particularly advantageous in overweight/obese patients, who are at increased risk of post-operative complications. Obese patients are however often denied MAAVR due to the perceived technical procedural difficulty. This retrospective analysis sought to determine the effect of BMI on post-operative outcomes in patients undergoing MAAVR.

Methods

Ninety isolated elective MAAVR procedures performed between May 2006–October 2013 were included. Intra- and post-operative data were prospectively collected. Ordinary least squares univariate linear regression analysis was performed to determine the effect of BMI as a continuous variable on post-operative outcomes. One-way ANOVA and Chi-squared testing was used to assess differences in outcomes between patients with BMI <25 (n = 36) and BMI ≥25 (n = 54) as appropriate.

Results

There was no peri-operative mortality, myocardial infarction or stroke. Univariate regression demonstrated longer cross-clamp times (p = 0.0218) and a trend towards increased bypass times (p = 0.0615) in patients with higher BMI. BMI ≥25 was associated with an increased incidence of hospital-acquired pneumonia (p = 0.020) and new-onset atrial fibrillation (p = 0.036) compared to BMI <25. However, raised BMI did not extend ICU (p = 0.3310) or overall hospital stay (p = 0.2614). Similar rates of sternal wound complications, inotrope requirements and renal dysfunction were observed in both normal- and overweight/obese-BMI groups. Furthermore, increasing BMI correlated with reduced mechanical ventilation time (p = 0.039) and early post-operative blood loss (p = 0.004).

Conclusions

Our results demonstrate that within the range of this study, MAAVR is a safe, reproducible and effective procedure, affording equivalent clinical outcomes in both overweight/obese and normal-weight patients considered for an isolated first-time AVR, with low post-operative morbidity and mortality. MAAVR should therefore be considered as an alternative surgical strategy to reduce obesity-related complications in patients requiring aortic valve replacement.

Early outcomes after isolated aortic valve replacement with rapid deployment aortic valve

OBJECTIVE

Minimal access aortic valve replacement is associated with favorable clinical outcomes; however, several meta-analyses have reported significantly longer crossclamp times compared with a full sternotomy. We examined the procedural and early safety outcomes after isolated rapid deployment aortic valve replacement by surgical approach in patients enrolled in the Surgical Treatment of Aortic Stenosis With a Next Generation Surgical Aortic Valve trial.

METHODS

The Surgical Treatment of Aortic Stenosis With a Next Generation Surgical Aortic Valve trial was a prospective, multicenter, single-arm study, with successful implants in 287 patients with aortic valve stenosis who underwent rapid deployment aortic valve replacement using the EDWARDS INTUITY Valve System (Edwards Lifesciences, Irvine, Calif). Patients were evaluated perioperatively for procedural times and technical success rates; at discharge, for hospital length of stay; and, at 30 days, for early adverse events.

RESULTS

A total of 158 patients underwent isolated aortic valve replacement through a full sternotomy (n = 71), upper hemisternotomy (n = 77), or right anterior thoracotomy (n = 10). Mean age at baseline was 75.7 ± 7.2 years. Mean aortic crossclamp and cardiopulmonary bypass times (minutes) were similar for full sternotomy and upper hemisternotomy, 43.5 ± 32.5/71.6 ± 41.8 and 43.1 ± 13.1/69.6 ± 19.1, respectively, and significantly longer for right anterior thoracotomy, 88.3 ± 18.6/122.2 ± 22.1 (P < .000). Early adverse event rates were similar, and in-hospital mortality rates were low regardless of surgical approach.

CONCLUSIONS

These data suggest that isolated rapid deployment aortic valve replacement through an upper hemisternotomy can lead to shorter crossclamp times than has been reported historically in the literature. This may facilitate minimal access aortic valve replacement by eliminating the issue of prolonged crossclamp times. Further, low in-hospital mortality and new permanent pacemaker implant rates were observed regardless of surgical approach.

Minimally Invasive Aortic Valve Replacement

With the advent of transcatheter aortic valve replacement and the emergence of rapid deployment aortic valves, there is a resurgent interest in minimizing the trauma of surgical aortic valve replacement (AVR). The present review summarizes the history of minimal access AVR and attempts to collate the existing evidence regarding minimal access AVR.

Concurrent Minimally Invasive Aortic Valve Replacement and Coronary Artery Bypass via Limited Right Anterior Thoracotomy

An 89-year-old man and an 80-year-old woman were treated surgically for critical aortic stenosis secondary to senile calcific aortic disease and high-grade calcified lesions in the ostium of the right coronary artery. Minimally invasive aortic valve replacement and concurrent coronary artery bypass grafting were performed concurrently through a 5-cm right anterior thoracotomy in the second intercostal space. Surgery was uncomplicated in both cases, with no adverse events. Both patients were alive and well at midterm follow-up. Concurrent minimally invasive aortic valve replacement and coronary artery bypass grafting can be performed successfully through a limited right anterior thoracotomy.

Minimally invasive aortic valve replacement - pros and cons of keyhole aortic surgery

Over the last twenty years, minimally invasive aortic valve replacement (MIAVR) has evolved into a safe, well-tolerated and efficient surgical treatment option for aortic valve disease. It has been shown to reduce postoperative morbidity, providing faster recovery and rehabilitation, shorter hospital stay and better cosmetic results compared with conventional surgery. A variety of minimally invasive accesses have been developed and utilized to date. This concise review demonstrates and discusses surgical techniques used in contemporary approaches to MIAVR and presents the most important results of MIAVR procedures.

Minimally invasive aortic valve replacement: 12-year single center experience

BACKGROUND

This study reports the single center experience on minimally invasive aortic valve replacement (MIAVR), performed through a right anterior minithoracotomy or ministernotomy (MS).

METHODS

Eight hundred and fifty-three patients, who underwent MIAVR from 2002 to 2014, were retrospectively analyzed. Survival was evaluated using the Kaplan-Meier method. The Cox multivariable proportional hazards regression model was developed to identify independent predictors of follow-up mortality.

RESULTS

Median age was 73.8, and 405 (47.5%) of patients were female. The overall 30-day mortality was 1.9%. Four hundred and forty-three (51.9%) and 368 (43.1%) patients received biological and sutureless prostheses, respectively. Median cardiopulmonary bypass time and aortic cross-clamping time were 108 and 75 minutes, respectively. Nineteen (2.2%) cases required conversion to full median sternotomy. Thirty-seven (4.3%) patients required re-exploration for bleeding. Perioperative stroke occurred in 15 (1.8%) patients, while transient ischemic attack occurred postoperative in 11 (1.3%). New onset atrial fibrillation was reported for 243 (28.5%) patients. After a median follow-up of 29.1 months (2,676.0 patient-years), survival rates at 1 and 5 years were 96%±1% and 80%±3%, respectively. Cox multivariable analysis showed that advanced age, history of cardiac arrhythmia, preoperative chronic renal failure, MS approach, prolonged mechanical ventilation and hospital stay as well as wound revision were associated with higher mortality.

CONCLUSIONS

MIAVR via both approaches is safe and feasible with excellent outcomes, and is associated with low conversion rate and low perioperative morbidity. Long term survival is at least comparable to that reported for conventional sternotomy AVR.

Sutureless prostheses and less invasive aortic valve replacement: just an issue of clamping time?

BACKGROUND

Recently, sutureless aortic bioprostheses have been increasingly adopted to facilitate minimally invasive aortic valve replacement. We aimed at evaluating the impact of the transition from conventional bioprostheses to the routine use of the 3f Enable prosthesis (Medtronic ATS Medical, Minneapolis, MN) for aortic valve replacement through ministernotomy.

METHODS

Between November 2009 and November 2012, 83 consecutive minimally invasive aortic valve replacement procedures were performed in our institution by the same surgeon through an upper T-shaped ministernotomy. The earliest 42 patients (group A) received a conventional bioprosthesis, and the later 41 patients (group B) received the sutureless 3f Enable valve. Aortic clamping and cardiopulmonary bypass times, early outcomes, and valve hemodynamics were compared.

RESULTS

There was no statistical intergroup difference in baseline characteristics. In-hospital mortality was 1% (a single nonvalve-related death). Average aortic clamping times in group A and group B were, respectively, 85 ± 17 and 47 ± 11 minutes (p < 0.0001); the cardiopulmonary bypass time was 108 ± 21 and 69 ± 15 minutes, respectively (p < 0.0001). There were three paravalvular leakages in group A (grade I) and four in group B (two grade I, and two grade II); three pacemaker implantations occurred in group B (p = 0.07); mean transvalvular gradient at discharge was 16.9 ± 9.1 mm Hg in group A and 11.4 ± 4.3 mm Hg in group B (p = 0.0007). During follow-up (average 25.5 ± 12.9 months), one structural valve deterioration was registered in group A, and was treated with a valve-in-valve procedure.

CONCLUSIONS

In our initial experience, the sutureless 3f Enable technology significantly reduced the clamping and cardiopulmonary bypass times, as well as the mean transvalvular gradient in aortic valve replacement through ministernotomy.

Minimally invasive aortic valve replacement versus aortic valve replacement through full sternotomy: the Brigham and Women's Hospital experience

BACKGROUND

Minimally invasive aortic valve surgery (mini AVR) is a safe and effective treatment option at many hospital centers, but there has not been widespread adoption of the procedure. Critics of mini AVR have called for additional evidence with direct comparison to aortic valve replacement (AVR) via full sternotomy (FS).

METHODS

Our mini AVR approach is through a hemi-sternotomy (HS). We performed a propensity-score matched analysis of all patients undergoing isolated AVR via FS or HS at our institution since 2002, resulting in 552 matched pairs. Baseline characteristics were similar. Operative characteristics, transfusion rates, in-hospital outcomes as well as short and long term survival were compared between groups.

RESULTS

Median cardiopulmonary bypass and cross clamp times were shorter in the HS group: 106 minutes [inter-quartile ranges (IQR) 87-135] vs. 124 minutes (IQR 90-169), P≤0.001, and 76 minutes (IQR 63-97) vs. 80 minutes (IQR 62-114), P≤0.005, respectively. HS patients had shorter ventilation times (median 5.7 hours, IQR 3.5-10.3 vs. 6.3 hours, IQR 3.9-11.2, P≤0.022), shorter intensive care unit stay (median 42 hours, IQR 24-71 vs. 45 hours, IQR 24-87, P≤0.039), and shorter hospital length of stay (median 6 days, IQR 5-8 vs. 7 days, IQR 5-10, P≤0.001) compared with the FS group. Intraoperative transfusions were more common in FS group: 27.9% vs. 20.0%, P≤0.003. No differences were seen in short or long term survival, or time to aortic valve re-intervention.

CONCLUSIONS

Our study confirms the clinical benefits of minimally invasive AVR via HS, which includes decreased transfusion requirements, ventilation times, intensive care unit and hospital length of stay without compromising short and long term survival compared to conventional AVR via FS.