Port-access aortic valve surgery: a technique in evolution

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.

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.

A systematic review of left ventricular cardio-endoscopic surgery

Better visualisation, accurate resection and avoidance of ventriculotomy associated with use of endoscopic devices during intracardiac surgery has led to increasing interest in their use. The possibility of combining a cardio-endoscopic technique with either minimally invasive or totally endoscopic cardiac surgery provides an incentive for its further development. Several devices have been used, however their uptake has been limited due to uncertainty around their impact on patient outcomes. A systematic review of the literature identified 34 studies, incorporating 54 subjects undergoing treatment of left ventricular tumours, thrombus or hypertrophic myocardium using a cardio-endoscopic technique. There were no mortalities (0%; 0/47). In 12 studies, the follow-up period was longer than 30 days. There were no post-operative complications apart from one case of atrial fibrillation (2.2%; 1/46). Complete resection of left ventricular lesion was achieved in all cases (100%; 50/50). These successful results demonstrate that the cardio-endoscopic technique is a useful adjunct in resection of left ventricular tumours, thrombus and hypertrophic myocardium. This approach facilitates accurate resection of pathological tissue from left ventricle whilst avoiding exposure related valvular damage and adverse effects associated with ventriculotomy. Future research should focus on designing adequately powered comparative randomised trials focusing on major cardiac and cerebrovascular morbidity outcomes in both the short and long-term. In this way, we may have a more comprehensive picture of both the safety and efficacy of this technique and determine whether such devices could be safely adopted for routine use in minimal access or robotic intra-cardiac surgery.

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.

A comparison of aortic valve replacement via an anterior right minithoracotomy with standard sternotomy: a propensity score analysis of 492 patients

OBJECTIVES

Right anterior minithoracotomy with central arterial cannulation is our preferred technique of minimally invasive aortic valve replacement (AVR). We compared perioperative outcomes with this technique to those via sternotomy.

METHODS

Between March 1999 and December 2013, 492 patients underwent isolated AVR via either sternotomy (SAVR, n = 198) or minimally invasive right anterior thoracotomy (MIAVR, n = 294) in our institution. Univariate comparisons between groups were made to evaluate overall outcomes and adverse events. To control treatment selection bias, propensity scores were constructed from core patient characteristics. A propensity score-stratified analysis of outcome and adverse events was then performed.

RESULTS

Overall mortality was 2.5 and 1.0% in the SAVR and MIAVR groups, respectively. Hospital and ICU stays were shorter, there was less intraoperative blood product usage, and fewer wound infections in the MIAVR group. There were no differences in other adverse events, including strokes. The composite end-point of alive and adverse event-free was significantly more common in the MIAVR group (83 vs 74%, P = 0.002). After adjusting for the propensity score, hospital and ICU stays remained shorter and intraoperative blood product usage remained less in the MIAVR group. There was no difference in mortality, stroke or other adverse events between groups.

CONCLUSION

Minimally invasive AVR via an anterior right thoracotomy with predominately central cannulation can be performed with morbidity and mortality similar to that of a sternotomy approach. There appear to be advantages to this minimally invasive approach when compared with sternotomy in terms of less intraoperative blood product usage, lower wound infection rates and decreased hospital stays. If mortality and the occurrence of adverse events are taken together, MIAVR may be associated with better outcomes. As minimally invasive AVR becomes more common, further long-term follow-up is needed and a prospective multicentre randomized trial would be warranted.

Conventional versus minimally invasive aortic valve replacement: pooled analysis of propensity-matched data

BACKGROUND

Minimally invasive aortic valve replacement (mAVR) is increasingly preferred over conventional AVR (cAVR). However, data comparing these procedures present conflicting results. Hence, we conducted a systematic review and meta-analysis comparing clinical results in these cohorts.

METHOD

Only randomized controlled trials (RCT) and propensity-matched observational studies (POS) (1998-2013) comparing clinical outcome of patients subjected to mAVR or cAVR were pooled. Continuous data was compared using mean/standardized mean difference (MD/SMD) while categorical results were pooled to obtain an odds ratio (OR) with a 95% confidence interval.

RESULTS

A total of 18 studies (6 RCT and 12 POS) (1973 mAVR patients; 2697 cAVR patients) were analyzed. The mean ischemic time was significantly longer with mAVR (MD 9.42 minutes [4.25-14.59]; p < 0.01). However, early mortality (mAVR [1.8%] and cAVR [3%]) was comparable (OR 0.70 [0.46-1.06]; p = 0.09). Postoperative ventilation time was slightly shorter after mAVR (7.5 vs 11.1 hours; p = 0.07), and hospital discharge was earlier after mAVR (MD -1.05 [-1.64 to -0.46]; p < 0.01). However, mAVR failed to reduce transfusion requirement (OR 0.77 [0.51-1.14]; p = 0.19) or pain scores (SMD -0.25 [-0.65 to 0.13]; p = 0.20). Postoperative atrial fibrillation (p = 0.67) and stroke (p = 0.79) rates were comparable. Pooled rate of conversion to full sternotomy was 2.5%. Cosmetic satisfaction could not be pooled due to reporting heterogeneity.

CONCLUSION

Minimally invasive aortic valve replacement can be performed safely despite the longer ischemic time. While minimally invasive surgery does demonstrate some advantages in postoperative recovery, we failed to find any other substantial improvement in outcome over conventional aortic valve replacement.

Aortic valve replacement via right minithoracotomy versus median sternotomy: a propensity score analysis

OBJECTIVE

The aim of this study was to define the relative role of a right minithoracotomy (RT) versus standard median sternotomy (ST) for open aortic valve replacement (AVR).

METHODS

A retrospective analysis was performed of all 1348 patients undergoing isolated, open AVR at a single institution during a 14-year period. Because relatively few patients were technically suitable for redo AVR with the RT approach (n = 20), all redo patients (n = 209) were excluded, leaving 1139 patients available for analysis. Patients converting from RT to ST approach (n = 15) were analyzed separately.

RESULTS

Relative to ST (n = 672), the RT patients (n = 452) were older with more stenosis but with more recent operation year, lower rate of congestive heart failure, higher ejection fraction, lower rate of endocarditis, and lower rate of renal disease than the ST AVR patients (all P < 0.0001). Right minithoracotomy AVR was associated with longer cardiopulmonary bypass times [157 (25) vs 131 (38), P = 0.0004] and clamp times [103 (20) vs 85 (27), P < 0.0001] but less transfusion (1.4 vs 3.4 U, P = 0.0003), less chest tube output (405 vs 950 mL, P < 0.0001), fewer reoperations for bleeding (0.4% vs 4%, P < 0.0001), shorter length of stay (6 vs 8 days, P = 0.03), and lower rate of atrial fibrillation (15% vs 20%, P = 0.03). Stroke, operative mortality, and survival were not significantly different between the groups.

CONCLUSIONS

Given the biases of retrospective propensity-adjusted analysis, these data suggest that RT AVR is a safe alternative to ST AVR in selected patients, with advantages of avoiding sternotomy with associated bleeding, transfusion, and delayed wound healing, at the expense of longer pump and clamp times.

Preoperative Vascular Imaging for Predicting Intraoperative Modification of Peripheral Arterial Cannulation during Minimally Invasive Mitral Valve Surgery

Objective

Minimally invasive mitral valve surgery using peripheral cannulation for cardiopulmonary bypass (CBP) is increasingly prevalent. Although conceptually straightforward, peripheral CBP involves challenges and risks specific to this method of perfusion. The utility of preoperative vascular imaging in predicting these technical challenges and preventing vascular complications was studied.

Methods

We performed a retrospective analysis of 73 consecutive patients undergoing minimally invasive mitral valve surgery using femorofemoral CBP with intraluminal aortic occlusion balloon catheter. All patients underwent preoperative computed tomography angiogram or magnetic resonance angiography to study the iliofemoral axes.

Results

None of the patients operated with this technique was found to have arterial stenoses. Patients with a femoral artery diameter of less than 7.3 mm needed bilateral or side-graft arterial cannulation significantly more frequently than patients with larger femoral arteries (46.2% vs 9.1%, P = 0.001). There was a trend toward more frequent modification of arterial cannulation strategy in patients with body surface area less than 1.7 m2 compared with larger patients (body surface area, 1.7–2.0) (26.3% vs 8.3%, P = 0.07). Patients needing high CBP flow rate (>5 L/min) were no more likely to need dual arterial cannulation (18.2% vs 19.1%, P = 0.68). No patient experienced a vascular complication.

Conclusions

This preliminary study suggests that preoperative vascular imaging and patient evaluation may predict difficulties with femoral cannulation and perfusion, which can lead to better preoperative planning and potentially prevent vascular complications. Further data will be accumulated and analyzed to confirm these findings.

Minimally invasive surgery for aortic stenosis in the geriatric patient: where are we now?

Minimally invasive aortic valve surgery has evolved with time and become the routine approach for aortic surgery in select surgical centers. The success of these procedures in the nonelderly has led some to embark on using minimal access techniques in the geriatric population as well. With the geriatric community often inflicted with the greatest disease burden, suffering not only from a valvular process but also cumulative comorbidities, geriatric patients may be the patients most likely to derive benefit from a minimally invasive approach. Alternative therapies for symptomatic aortic stenosis include conventional full-sternotomy aortic valve replacement in addition to transcatheter aortic valve implantation. Each option has its advantages and disadvantages. The role of minimal access aortic valve surgery and its impact on the progressively aging population in the face of conventional surgery and transcatheter technology is discussed.

Aortic Valve Replacement through Right Minithoracotomy in 306 Consecutive Patients

Objective

To define the role and early results of aortic valve surgery through a right minithoracotomy.

Methods

A retrospective analysis was performed on 306 consecutive patients undergoing aortic valve replacement through an 8-cm right minithoracotomy in the second intercostal space. The initial experience was included. The right second and third ribs were detached from the sternum in most cases and repaired at the end of each case. Most operations were performed using anterograde and retrograde cardioplegic arrest with percutaneous femoral venous cannulation and direct aortic cannulation through the incision. Standard instruments were used with direct digital knot tying.

Results

Mean age was 65 ± 14 (range, 20–90) years. Aortic valve disease cause was calcific disease in 160 of 306 (52%) patients, bicuspid disease in 95 of 306 (31%) patients, and endocarditis in 9 of 306 (3%) patients. Previous cardiac surgery was present in 13 of 306 (4%) patients. Biologic prostheses were used in 240 of 306 (78%) patients. Median valve size was 23 mm. Mean clamp times and pump times were 103 ± 26 and 158 ± 35 minutes, respectively. Median postoperative length of stay was 5 days. Thirty-day mortality was found in 4 of 306 (1%) cases. There were no deep wound infections or mediastinitis. Stroke occurred in 5 of 306 (1.6%) patients, and new pacemaker required in 11 of 306 (4%) patients. Reoperation for bleeding occurred in 2 of 306 (1%) patients. Conversion to median sternotomy occurred in 15 of 306 (5%) patients caused by chest wall anatomy (n = 7), bleeding (n = 3), coronary disease (n = 2), or aortic disease (n = 3). Patients were allowed to return to driving or preoperative activity in 2 weeks. With a mean follow-up of 2.8 ± 2.2 years, one patient required reoperation for aortic root disease.

Conclusions

Right minithoracotomy is a safe but limited alternative to sternotomy in isolated aortic valve replacement. This approach may be particularly valuable in some higher risk, elderly patients and opens options for a hybrid approach combined with percutaneous coronary angioplasty.

Aortic valve replacement surgery: comparison of outcomes in matched sternotomy and PORT ACCESS groups

BACKGROUND

In the past decade, minimally invasive approaches have been developed for aortic valve surgery. We reviewed our data to determine if the use of the PORT ACCESS technique has improved hospital morbidity and mortality.

METHODS

Data were collected on 90 patients who had a replacement of their aortic valve using PORT ACCESS procedures (PORT ACCESS aortic valve replacement [PAVR]). This group was then matched 1:4 to a control group having aortic valve replacement surgery using a standard sternotomy approach.

RESULTS

The two groups had no statistically significant differences in preoperative risk factors. The perioperative and 30-day outcomes from the matched AVR and PAVR groups showed no mortalities in the PAVR group and 3.1% in the AVR group. Mean length of stay was shorter for PAVR patients (7.2 +/- 5.0 days; median 6 days) compared with the mean stay in the sternotomy group (8.5 +/- 9.5 days; median 6 days), PAVR patients also had statistically significant shorter intensive care unit stays, and time on ventilator. The number of patients needing ventilator support postoperatively was significantly lower in the PORT ACCESS group. Cross-clamp and perfusion times were longer in the PAVR group. No other morbidity was significantly different between groups, except for postoperative tamponade (higher in PAVR group).

CONCLUSIONS

In this analysis of matched patients, the patients having aortic valve replacement using PORT ACCESS procedures, spent a shorter time in the intensive care unit and had less need for postoperative ventilator usage (both number of patients using a ventilator and the mean time of use) in comparison with patients undergoing conventional sternotomy.

Port-access aortic valve replacement

A 42-year-old man suffering from massive aortic valve regurgitation with mild stenosis because of a bicuspid valve underwent surgery in May 2007. The surgical procedure was performed through a right anterolateral thoracotomy using the peripheral cannulation method. Cardiac arrest was achieved by direct aortic cross-clamping and selective cardioplegia delivery. The aortic valve was replaced with a bioprosthesis. The operation and aortic cross-clamping periods were 265 and 117 min, respectively. The patient's recovery was uneventful, and he was discharged from hospital 8 days after surgery.

[Minimally invasive direct cardiac surgery with the jakoscope retractor]

The authors present a surgical retractor named jakoscope, useful in the field of abdominal, urological, vascular, thoracic and cardiac surgery procedures. This multifunctional device offers the possibility to utilize Minimally Invasive Direct Access Surgical Technology (MIDAST) in the above mentioned surgical specialties. In their department the authors use the jakoscope retractor for aortic valve replacement, off-pump coronary bypass operations and radiofrequency pulmonary vein ablation by mini-thoracotomy approach. In this report they published for the first time their experience with jakoscope device in the field of cardiac surgery. In these operations the device assured adequate minimally invasive direct access, without complications.

Percutaneous Aortic Valve Replacement

Objective

To improve the outcome of percutaneous valve replacement in aortic stenosis endovascular resection of calcified aortic valves will be necessary. In this study different sealing methods were evaluated. The focus of this research was feasibility and mechanical functionality in human anatomy.

Methods

The aortic valve isolation chamber (AVIC) is a catheter-based system to seal the aortic valve during resection, and was installed antegrade and retrograde. Firstly, AVIC was inserted antegrade via the cardiac apex in human postmortem models (n = 2), and secondly in porcine in vivo models under extra corporeal circulation (n = 5). Endoscopic inspection of the valve was recorded. AVIC was installed via a port system through the descending aorta. Micro- and macropathologies were performed.

Results

AVIC transapical deployment in the two human models took 3 and 4 minutes respectively and 2.2 ± 1.3 minutes in average in the porcine model. From the descending aorta, the deployment took 9.3 ± 5.5 minutes. Fluoroscopy and macroscopy demonstrated sealed chambers. Microscopic and histologic analysis demonstrated no profound damages of the surrounding tissue.

Conclusion

This study demonstrates the feasibility of transapical and retrograde endovascular sealing of the aortic valve in vitro and in vivo in nonbeating hearts.

Port-Access-Assisted Aortic Valve Replacement: A Comparison of Minimally Invasive and Conventional Techniques

BACKGROUND

A hybrid Port-Access (PA) approach to aortic valve surgery (MPAVR) was designed as a less invasive aortic valve operation. The approach combines components of Port-Access technology with conventional cardiac surgical techniques via a limited sternal incision. This technique is compared to conventional aortic vale replacement (CAVR) for safety and efficacy.

METHODS

One hundred eighty patients had aortic valve surgery between January 1, 2000, and June 30, 2004. Fifty-eight patients (32%) had primary isolated aortic valve replacement, 22 of those 58 patients (38%) underwent MPAVR procedures consisting of a limited inverted-T sternotomy, direct aortic cannulation, a percutaneous PA endocoronary sinus cardioplegia catheter, an endovent pulmonary artery catheter, and a percutaneous femoral endovenous return catheter. Thirty-six patients (62%) had aortic valve replacement by sternotomy and standard cardiopulmonary bypass techniques. The MPAVR and CAVR groups were compared for demographics and intraoperative and postoperative outcomes.

RESULTS

Age, obesity, diabetes, New York Heart Association classification, ejection fraction, and other patient characteristics were not significantly different between the groups. MPAVR patients had lower Society of Thoracic Surgery risk scores (3.1 versus 3.9; P = .277). MPAVR patients were more likely to receive a stentless valve (36% versus 11%; P = .042) and required longer operative times (237 min versus 189 min; P <.001). Postoperative complications were minimal and equivalent. A single mortality in the CAVR group resulted in an overall mortality of 1.7%.

CONCLUSION

This hybrid, less invasive PA-assisted approach to aortic valve surgery is safe and effective. A total sternotomy can be avoided in selected aortic valve patients. Results equivalent to CAVR can be expected with this minimal access operation.