Prospective comparison of minimally invasive and standard techniques for aortic valve replacement: initial experience in the first hundred patients

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.

Safety and Efficacy of the Transaxillary Access for Minimally Invasive Aortic Valve Surgery

Background and Objectives: Transaxillary access is one of the latest innovations for minimally invasive aortic valve replacement (MICS-AVR). This study compares clinical performance in a large transaxillary MICS-AVR group to a propensity-matched sternotomy control group. Materials and Methods: This study enrolled 908 patients undergoing isolated AVR with a mean age of 69.4 ± 18.0 years, logistic EuroSCORE of 4.0 ± 3.9%, and body mass index (BMI) of 27.3 ± 6.1 kg/m2. The treatment group comprised 454 consecutive transaxillary MICS-AVR patients. The control group was 1:1 propensity-matched out of 3115 consecutive sternotomy aortic valve surgeries. Endocarditis, redo, and combined procedures were excluded. The multivariate matching model included age, left ventricular ejection fraction, logistic EuroSCORE, pulmonary hypertension, coronary artery disease, chronic lung disease, and BMI. Results: Propensity-matching was successful with subsequent comparable clinical baselines in both groups. MICS-AVR had longer skin-to-skin time (120.0 ± 31.5 min vs. 114.2 ± 28.7 min; p < 0.001) and more frequent bleeding requiring chest reopening (5.0% vs. 2.4%; p < 0.010), but significantly less packed red blood cell transfusions (0.57 ± 1.6 vs. 0.82 ± 1.6; p = 0.040). In addition, MICS-AVR patients had fewer access site wound abnormalities (1.5% vs. 3.7%; p = 0.038), shorter intensive care unit stays (p < 0.001), shorter ventilation times (p < 0.001), and shorter hospital stays (7.0 ± 5.1 days vs. 11.1 ± 6.5; p < 0.001). No significant differences were observed in stroke > Rankin 2 (0.9% vs. 1.1%; p = 0.791), renal replacement therapy (1.5% vs. 2.4%; p = 0.4762), and hospital mortality (0.9% vs. 1.5%; p = 0.546). Conclusions: Transaxillary MICS-AVR is at least as safe as AVR by sternotomy and can be performed in the same time frame. Its advantages are fewer transfusions and quicker postoperative recovery with a significantly shorter hospital stay. The cosmetic result and unrestricted physical abilities due to the untouched sternum and ribs are unique advantages of transaxillary access.

Ministernotomy or sternotomy in isolated aortic valve replacement? Early results

Introduction

Aortic valve replacement (AVR) is the gold standard in treating symptomatic aortic valve defects. To improve the healing process and limit the trauma, the minimally invasive approach was introduced.

Aim

To compare the peri- and post-operative results of aortic valve replacement performed via conventional full sternotomy (con-AVR) and of AVR performed via partial upper sternotomy (mini-AVR).

Material and methods

The total study population was divided into 2 demographically homogeneous groups: mini-AVR (n = 74) and con-AVR (n = 76). There were no statistically significant differences in preoperative echocardiography.

Results

Aortic cross-clamp time and cardiopulmonary bypass time were significantly longer in the mini-AVR group. Shorter mechanical ventilation time, hospital stay and lower postoperative drainage were observed in the mini-AVR group (p < 0.05). Biological prostheses were more frequently implanted in the mini-AVR group (p < 0.05). Patients from the mini-AVR group reported less postoperative pain. No significant differences were found in the diameter of the implanted aortic prosthesis, the amount of inotropic agents and painkillers, postoperative left ventricular ejection fraction (LVEF), medium and maximum transvalvular gradient or the number of transfused blood units. There were no differences in the frequency of postoperative complications such as mortality, stroke, atrial fibrillation, renal failure, wound infection, sternal instability, or the need for rethoracotomy.

Conclusions

Ministernotomy for AVR is a safe method and does not increase morbidity and mortality. It significantly reduces post-operative blood loss and shortens hospital stay. Ministernotomy can be successfully used as an alternative method to sternotomy.

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.

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.

The economic value of INTUITY in aortic valve replacement

OBJECTIVE

The recent development of the EDWARDS INTUITY Elite™ (EIE) valve system enables the rapid deployment of a prosthetic surgical heart valve in an aortic valve replacement (AVR) procedure via both the minimally invasive (MISAVR) and conventional (CAVR) approaches. In order to understand its economic value, this study performed a cost evaluation of the EIE valve system used in a MIS rapid-deployment approach (MIS-RDAVR) vs MISAVR and CAVR, respectively, compared to standard prosthetic aortic valves.

METHODS

A simulation model was developed using TreeAge (and validated with MS Excel) to compare the inpatient utilization and complication costs for each treatment arm. Thirty-day clinical end-points for the MIS-RDAVR (mortality and complications) were taken from the TRANSFORM trial; and a best evidence review of the published literature was used for the MISAVR and CAVR approaches. Studies were pooled and parameter estimates were weighted by sample size in order to compare the TRANSFORM patients. Cost data (2016 USD) were taken from the Premier database. Incremental cost and cost-effectiveness was assessed and one-way/probabilistic sensitivity analyses performed to gauge the robustness of the results.

RESULTS

MIS-RDAVR costs $2,621 less than CAVR and had lower mortality rates, making it a superior (dominant) technology relative to CAVR. MIS-RDAVR costs $4,560 more than MISAVR, but was associated with an additional 0.20 life years-per-patient. This implies a cost-effectiveness ratio of $22,903 per-life-year-gained. Thus, MIS-RDAVR is cost-effective compared to MISAVR.

CONCLUSIONS

The EIE valve system deployed in a MIS approach appears to be a cost-effective technology compared to MISAVR and CAVR. When compared to CAVR it may achieve cost savings as well. These results suggest that MIS-RDAVR confers superior economic value compared to both standard MISAVR and CAVR via lowered key complication rates (re-operation, renal complications, wound infection, TIA, endocarditis) and utilization (cross-clamp time, hospital ward days).

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.

Mini-aortic surgery with percutaneous cannulation and rapid-deployment valve

Background

We aimed to evaluate the results of the combined use of rapid-deployment valves, percutaneous cardioplegia delivery and left heart venting during minimally invasive aortic valve replacement surgery.

Methods

We identified 2 propensity-matched cohorts of patients who underwent primary elective isolated minimally invasive aortic valve surgery at our center over a 3-years period: 30 patients in group A had a conventional valve prosthesis and 30 patients in group B received a rapid-deployment valve using percutaneous cardioplegia delivery and percutaneous left heart venting. Skin incision length, intraoperative times, postoperative hospital outcomes, and 30-day echocardiographic results were compared between the 2 groups.

Results

Patients in group B had significantly shorter operative times and shorter skin incisions compared to group A (total operative time 196.0 ± 40.6 vs. 225.1 ± 30.8 min, respectively, p < 0.003; cardiopulmonary bypass time 79.9 ± 10.6 vs. 92.9 ± 17.2 min respectively, p < 0.001; crossclamp time 52.3 ± 9.6 vs. 74.9 ± 10.2 min, respectively, p < 0.001; incision length 3.6 ± 0.5 vs. 6.0 ± 0.6 cm, respectively, p < 0.001). Postoperative hospital outcomes and echocardiographic evaluation showed no significant differences.

Conclusions

The combined use of rapid-deployment valves, percutaneous cardioplegia, and left heart venting is safe and effective and allows a significant reduction of the skin incision together with a significant reduction of intraoperative times without affecting hospital outcomes or hemodynamic performance of the prosthetic valves.

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.

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.

Aortic valve replacement through J-shaped partial upper sternotomy

The introduction of minimally invasive techniques in general surgery, in the late 1980s, influenced cardiac surgery as well. This led to the emergence of several minimal access approaches for aortic valve replacement (AVR). Currently, the upper partial sternotomy with unilateral J-shaped extension to the right through the fourth intercostal space is the most popular minimal access approach. This approach offers the comfort factor of sternotomy, improved cosmetic result, preserved respiratory mechanics, and last but not the least cost saving as no new equipment is required. On the other hand, inability to visualize the whole heart, adequately de-air the left heart, and failure to apply epicardial pacing wires are some of the perceived disadvantages of this approach. This article provides a comprehensive review of the indications, contraindications, technical aspects, outcomes, advantages and disadvantages of AVR through J-shaped partial upper sternotomy.

Minimally invasive heart valve surgery: already established in clinical routine?

Cardiac valve replacement with the need for open heart surgery still has the highest morbidity and mortality rates among routine cardiac surgery, with the exception of aortic aneurysm repair and surgery for congenital heart defects. Reducing invasiveness is a desirable goal, and different strategies and approaches have been used to achieve this with valve repair or replacement less invasive. Despite the good results reported with minimally invasive techniques, time on extracorporal circulation is always longer compared with the conventional procedures. Since these techniques do not reduce real invasiveness but rather improve the cosmetic results, minimal-access surgery would be a better nomenclature. With the exception of patients at a high risk for sternal infections or redo heart operations, a reduction in postoperative morbidity by the avoidance of a median sternotomy is not yet definitely proven. Meanwhile, most surgeons comply with the demand for minimally invasive surgery posed by patients by reducing the length of the incision in aortic valve replacement and by using a right anterolateral approach with a limited incision for mitral valve operations. However, the use of endoscopic or robotic devices is limited to a few centers, and has not yet found its way into clinical routine. Nonetheless, minimally invasive or minimal-access surgery is now established in many centers, and patients should always be informed of these techniques. When this information is provided objectively and patient selection is carried out accurately, these alternative approaches can help to improve postoperative convalescence.

Sutureless Aortic Valve Replacement via Partial Sternotomy

OBJECTIVE

: For elderly patients with symptomatic aortic valve stenosis, aortic valve replacement with tissue valves is still the treatment of choice. Stentless valves were introduced to clinical practice for better hemodynamic features as compared with stented tissue valves. However, the implantation is more complex and time demanding, especially in minimal invasive aortic valve replacement. We present our clinical data on 22 patients having received a sutureless ATS 3f Enable aortic bioprosthesis via partial upper sternotomy.

METHODS

: The procedure was performed using CPB with cardioplegic arrest. After resection of the stenotic aortic valve and debridement of the annulus, the valve was inserted and released. Mean age was 79 years, and mean logistic Euroscore was 13. Subvalvular myectomy was performed in two patients. Prosthetic valve sizes were 19 mm (n = 1), 21 mm (n = 7), 23 mm (n = 6), 25 mm (n = 6), and 27 mm (n = 2).

RESULTS

: Implantation of the valve required 10 ± 6 minutes. Cardiopulmonary bypass and aortic crossclamp time were 87 ± 16 and 55 ± 11 minutes, respectively. Early mortality (<90 days) was 9% (2 patients). No paravalvular leakage was detected intraoperatively or in follow-up echocardiography. The mean transvalvular gradients were 9 ± 6 mm Hg at discharge and 8 ± 2 mm Hg at 1-year follow-up.

CONCLUSIONS

: Sutureless valve implantation via partial sternotomy is feasible and safe with the ATS 3f Enable bioprosthesis. Reduction of cardiopulmonary bypass and aortic crossclamp time seems possible with increasing experience. Hemodynamic data are very promising with low gradients at discharge and after 12 month. Sutureless valve implantation via minimal invasive access may be an alternative treatment option for elderly patients with high comorbidity.

Perceval S sutureless aortic valve prosthesis implantation via a right anterior minithoracotomy

The rapid development and refinement of techniques over the past decade have led to the realization that a minimally invasive approach enables aortic valve surgery to be performed with results, at the very least, equivalent to those of traditional (open) valve surgery done in experienced centres. Minimally invasive aortic valve replacement (MIAVR) has now evolved into a safe, efficient treatment option providing greater patient satisfaction and fewer complications. For rapidly ageing population of industrialized countries, aortic valve replacement (AVR) has become the most frequent heart valve surgery. However, transcatheter aortic valve implantation techniques and sutureless aortic valve prostheses recently introduced into clinical practice are challenging now the results of MIAVR in certain high surgical risk patients. Right anterior minithoracotomy results in excellent exposure and a safe conduct of AVR. The minithoracotomy is performed via the second intercostal space with a 6-7&emsp14;cm long skin incision and no bone transection. After direct aortic and peripheral venous cannulation, aortic valve is exposed in a conventional manner, and further conduct of the intervention is not different from the sutureless AVR in median sternotomy. Herein, we discuss the indications, surgical technique and initial results of sutureless AVR through right anterior minithoracotomy.

The golden age of minimally invasive cardiothoracic surgery: current and future perspectives

Over the past decade, minimally invasive cardiothoracic surgery (MICS) has grown in popularity. This growth has been driven, in part, by a desire to translate many of the observed benefits of minimal access surgery, such as decreased pain and reduced surgical trauma, to the cardiac surgical arena. Initial enthusiasm for MICS was tempered by concerns over reduced surgical exposure in highly complex operations and the potential for prolonged operative times and patient safety. With innovations in perfusion techniques, refinement of transthoracic echocardiography and the development of specialized surgical instruments and robotic technology, cardiac surgery was provided with the necessary tools to progress to less invasive approaches. However, much of the early literature on MICS focused on technical reports or small case series. The safety and feasibility of MICS have been demonstrated, yet questions remain regarding the relative efficacy of MICS over traditional sternotomy approaches. Recently, there has been a growth in the body of published literature on MICS long-term outcomes, with most reports suggesting that major cardiac operations that have traditionally been performed through a median sternotomy can be performed through a variety of minimally invasive approaches with equivalent safety and durability. In this article, we examine the technological advancements that have made MICS possible and provide an update on the major areas of cardiac surgery where MICS has demonstrated the most growth, with consideration of current and future directions.

Mini-sternotomy for aortic valve replacement reduces the length of stay in the cardiac intensive care unit: meta-analysis of randomised controlled trials

Background Mini-sternotomy for isolated aortic valve replacement aims to reduce operative trauma hastening recovery and improving the cosmetic outcome of cardiac surgery. The short-term clinical benefits from the mini-sternotomy are presumed to arise because the incision is less extensive and the lower half of the chest cage remains intact. The basic conduct of virtually all other aspects of the aortic valve replacement procedure remains the same. Therefore, similar long-term outcomes are to be expected. Objectives To conduct a meta-analysis of the only available randomised controlled trials (RCT) in the published English literature. Data sources Electronic search for relevant publications in MEDLINE, EMBASE and CENTRAL databases were performed. Four studies met the criteria. Study eligibility criteria RCT comparing minimally invasive (inverted C or L (J)-shaped) hemi-sternotomy versus conventional sternotomy for adults undergoing isolated aortic valve replacement using standard cardiopulmonary bypass technique. Methods Outcome measures were the length of positive pressure ventilation, blood loss, intensive care unit (ICU) and hospital stay. Results The length of ICU stay was significantly shorter by 0.57 days in favour of the mini-sternotomy group (CI -0.95 to -0.2; p=0.003). There was no advantage in terms of duration of ventilation (CI -3.48 to 0.36; p=0.11). However, there was some evidence to suggest a reduction in blood loss and the length of stay in hospital in the mini-sternotomy group. This did not prove to be statistically significant (154.17 ml reduction (CI -324.51 to 16.17; p=0.08) and 2.03 days less (CI -4.12 to 0.05; p=0.06), respectively). Limitations This study includes a relatively small number of subjects (n=220) and outcome variables. The risk of bias was not assessed during this meta-analysis. Conclusion Mini-sternotomy for isolated aortic valve replacement significantly reduces the length of stay in the cardiac ICU. Other short-term benefits may include a reduction in blood loss or the length of hospital stay.

Versatility of hemisternotomy for cardiac surgery

BACKGROUND

Hemisternotomy has been suggested as a way to reduce morbidity by limiting the invasiveness of surgical interventions but it is often limited to aortic valve disease. This study reviews the experience of one center employing hemisternotomy and compares patient outcomes, both in-hospital and post-discharge, with a matched group of full sternotomy patients.

METHODS

Propensity scores were used to match all hemisternotomy valve cases (Hemi) to full sternotomy valve cases (Full) (1:2). An in-hospital composite outcome (COMP) was defined as mortality, stroke, deep sternal wound infection, sepsis, or return to operating room (OR) for bleeding or valve dysfunction. Provincial administrative health databases were used to determine freedom from mortality and hospital readmission for cardiac cause.

RESULTS

During the study period, 70 patients received hemisternotomy for various cardiac surgical interventions with only 38 patients undergoing isolated aortic valve replacement. Examining valve surgery exclusively, 65 Hemi were matched to 130 Full. In-hospital complications were low in both groups, with 1.0% mortality and a non-significant trend toward COMP in the Full group (Hemi=4.6%; Full=8.5%; p=0.39). Ventilation time was significantly decreased in Hemi (median four vs. six hours; p=0.002). At two years follow-up, survival was excellent for both (Hemi=95.0%; Full=93.6%) and freedom from cardiac morbidity (Hemi=76.8%, Full=73.2%) was comparable.

CONCLUSION

Hemisternotomy appears to be a safe, effective, and versatile alternative for many cardiac surgical interventions. With a median follow-up of four years, this study represents the longest cardiac morbidity follow-up for hemisternotomy patients. However, we were unable to conclusively show a morbidity benefit with this incision.

Minimally Invasive Surgery for Valve Disease

Heart valve surgery evolved since the early 1960s toward routine clinical application with good patient outcome. Different surgical techniques and valve prostheses have been developed. Thus standard procedures were continuously established. The different surgical procedures have now gained widespread clinical acceptance with good patient outcomes. Aortic valve stenosis and mitral valve incompetence are the most frequently acquired heart valve lesions in the western communities. Usually such lesions reach clinical significance in patients during their fifth to eighth decade of life. Standard surgical techniques of aortic valve repair and mitral valve replacement or repair result in persistent cure of the disease. Surgical access was gained using conventional lateral thoracotomies in the early days and later on using median sternotomy. Minimally invasive techniques, mostly by a partial sternotomy for the aortic and a lateral minithoracotomy for the mitral position, have been increasingly applied to improve patient outcome since the mid 1990s. At specialized centers these techniques have evolved as clinical standard allowing all different valve procedures to be safely performed. Patient recovery is fast leading to a significant improvement in the individual's quality of life. Minimally invasive valve surgery can be considered the standard approach and will reach more widespread clinical application.

Percutaneous and surgical treatment of aortic stenosis

Aortic stenosis due to calcific degeneration is the most common valvular disorder among the elderly. With the growing elderly population, the prevalence of this disease will continue to increase. Based on converging lines of evidence linking calcific aortic stenosis with atherosclerosis, there has been interest in drug therapy to slow the progression of aortic stenosis. Unfortunately, recently completed prospective trials have been disappointing. Mechanical measures remain the principal form of therapy. Among percutaneous techniques, aortic valvuloplasty provides only transient and modest benefit at a significant risk of stroke and vascular injury. However, aortic valvuloplasty can play a useful role in stabilizing patients who require additional attention prior to definitive surgery. Building on this foundation, a bold new technique of percutaneously implanting a balloon-mounted valve has been developed. Although promising, there have been relatively few patients treated in this fashion (at a single center) and with only limited follow-up. Surgical treatment, specifically valve replacement, is still the definitive treatment of choice for patients with symptomatic aortic stenosis. Surgeons and patients must choose between a variety of models of both tissue and mechanical valves and a variety of surgical approaches. Recent trends include the use of tissue valves in increasingly younger patients and continued interest in alternatives to full median sternotomy in approaching the valve.

Will minimally invasive valve replacement ever really be important?

PURPOSE OF REVIEW

Most cardiac surgical centers worldwide have instituted some form of minimally invasive surgery into their operative armamentarium. However, skepticism still remains whether minimally invasive valve replacement will ever really be important. This review first addresses the definition of minimally invasive surgery and then analyzes the possible advantages and disadvantages of minimally invasive valvular surgery.

RECENT FINDINGS

The nomenclature for minimally invasive surgery is ill defined. Minimally invasive valve replacement is a safe and effective procedure compared with total sternotomy. The advantages of minimally invasive valve replacement are the length of stay and disposition after discharge, postoperative bleeding, cosmesis, and postoperative pain, whereas the main disadvantage involves the operative times early in the learning curve.

SUMMARY

Minimally invasive valve replacement is beneficial and will continue to evolve as an important treatment option for patients with valvular heart diseases.

Advances in Heart Valve Surgery

Heart valve surgery continues to evolve in a dynamic fashion. While the exact role of minimally invasive approaches still needs to be defined, progress has been made in the development of new bioprostheses and their durability. Most importantly, valve repair has been standardized for the mitral and introduced for the aortic valve with results that have been superior to valve replacement. Selection of the optimal procedure for the individual patient is now facilitated. In the future, a wider application of repair procedures and further improvements of biologic valves can be anticipated not only to influence long-term results but also the decision-making process for conservative or surgical treatment.