Minimally invasive mitral valve surgery: a systematic review and meta-analysis

Video assistance in mitral surgery: reaching the "Thru" port access

BACKGROUND

Minimally invasive and video assisted mitral valve surgery has been used widely since beginning of 20^th. Different reduced surgical approaches allowed replacing or repairing a mitral valve sparing sternal incision. Nevertheless the most used strategy has been in the last years the right mini thoracotomy and the extra thoracic cardiopulmonary bypass (CPB). The main goal is avoiding sternal approach for mitral valve procedures and improve postoperative course of the patients. Some postoperative complication likes blood loss, need for transfusion, prolonged intubation and infection has been reduced using this alternative technique. A special advantages has been reported in elderly or high risk patients and in redo cases.

METHODS

Several cardiac centres using videoscopy and a revolutionary set up for CPB management and aortic occlusion have adopted the approach. The team approach, including surgeon, anaesthesiologist, nurse, cardiologist and perfusionist, is crucial for a safe and effective realization of this surgical strategy. The proper use of catheters and Seldinger skilfulness, and the guidance of trans-esophageal echocardiography (TEE) during the procedure are two milestones of this technique. A careful and progressive learning curve is required for all the components of the team. In fact some peculiarity likes modified surgical instruments, 3D and Full HD video assisted view, percutaneous canulation for CPB and myocardial protection, etc., make this procedure challenging for all members of the operative room (OR) team.

RESULTS

Our favourite set-up include right mini thoracotomy in the IV intercostal space, femoral vein and arterial canulation and an additional venous cannula in the superior vena cava for the drainage of the upper part of the body. Aortic occlusion is achieved usually using an endo-aortic clamp positioned by means of continuous and careful TEE guidance. A mitral valve procedure is realized by direct or video guided view; using adapted and shaft instruments or special atrial retractors all standard techniques are used in this setting.

CONCLUSIONS

The literature reports and our published results showed the technique is safe, easy to replicate and allows an excellent rate of valve repair even in more complex patients.

Late redo-port access surgery after port access surgery

OBJECTIVES

This study presents the first report on short- and long-term outcomes in redo-port access surgery after previous port access surgery (redo-PAS-PAS) for new or recurrent mitral valve (MV) and tricuspid valve (TV) disease.

METHODS

Our current surgical team performed redo-PAS-PAS in 26 consecutive patients who had previous port access surgery (mean age 65.8 ± 13.3 years, 46.2% female, 42.3% older than 70 years, mean logistical EuroSCORE 22.5 ± 21.6%) between 1 February 1997 and 30 June 2014. Surgical indications included among others MV prosthesis dysfunction (n = 8, 30.8%), endocarditis (n = 10, 38.5%) and TV dysfunction (n = 3, 11.5%). The mean time interval between primary PAS and redo-PAS-PAS was 70.32 ± 57.4 months.

RESULTS

Redo-PAS-PAS procedures included MV replacement (n = 19, 73.1%), MV repair (n = 5, 19.2%), and TV repair (n = 2, 7.7%). Sternotomy conversion was required in 5 patients (19.2%), of which 4 (15.4%) were early conversions due to lung adhesion and 1 (3.8%) due to a late intraoperative complication. The mean cardiopulmonary bypass and cross-clamp times were 163.3 ± 57.9 and 101.2 ± 43.8 min, respectively. Postoperative mechanical ventilation longer than 72 h was required in 4 patients (15.4%). In-hospital morbidities included hospital-acquired pneumonia (n = 3, 11.5%), postoperative air leaks (n = 2, 7.7%) and revision for bleeding (n = 1, 3.8%). The mean length of hospital stay was 16.1 days. Long-term clinical and echocardiographic follow-up were 48.3 ± 39.2 and 44.6 ± 32.9 months, respectively. The Kaplan-Meier analyses for survival and freedom from mitral and tricuspid valve reintervention (n = 26) at 5 years were 83.9 and 95.8%, respectively, with 91.3% of surviving patients classified as being NYHA II or less. Echocardiographic follow-up showed no residual mitral regurgitation more than grade I in all redo mitral valve repairs and no paravalvular leak post-valve replacement.

CONCLUSIONS

Redo-PAS-PAS is our routine approach and we apply this strategy in the majority of patients who had previous port access surgery. The predicted procedure-related mortality, morbidities, patient satisfaction and long-term outcomes are favourable.

Recent Developments in Minimally Invasive Cardiac Surgery: Evolution or Revolution?

Intraluminal aortic clamping has been achieved until now by means of a sophisticated device consisting of a three-lumen catheter named Endoclamp, which allows at the same time occlusion of the aorta, antegrade delivering of cardioplegia, and venting through the aortic root. This tool has shown important advantages allowing aortic occlusion and perfusate delivering without a direct contact with ascending aorta reducing meanwhile the risk of traumatic and/or iatrogenic injuries. Recently, a new device (Intraclude catheter) with the same characteristics and properties has been proposed and introduced in clinical practice. The aim of this paper is to investigate the differences between Endoclamp and Intraclude catheters and to analyze the advantages advocated by this new device for intraluminal aortic occlusion since it is noticeable as these new technological tools are gaining more and more attractiveness due to their appraised clinical efficacy.

The "Spacemaker", a New Device for Minimally Invasive Cardiothoracic Surgery: An Evaluation and Feasibility Study

OBJECTIVE

Our aim was to evaluate a new inflatable lung retractor, the "Spacemaker", and its efficacy in facilitating minimally invasive cardiothoracic surgery without the need of one lung ventilation or carbon dioxide overpressure insufflation.

METHODS

The device was tested in 12 anesthetized pigs (90-100 kg) placed on standard endotracheal ventilation. The device was introduced into the right or left side of the chest, depending on the intended procedure to be performed, via a 3-cm incision in the fifth intercostal space. A total of seven animals were used to evaluate hemodynamic and respiratory response to the device, whereas another five animals were used to assess the feasibility of a variety of minimally invasive cardiothoracic surgical procedures.

RESULTS

Introduction was easy and unhindered. The device was inflated up to 0.6 bar, thereby pushing the lung tissue gently away cranially, posteriorly, and caudally without interfering with pulmonary function or resulting in respiratory compromise. In addition, hemodynamics remained stable throughout the experiments. Different closed-chest surgical procedures such as left atrial appendage exclusion, pulmonary vein exposure, pacemaker lead placement, and endoscopic stabilization for coronary surgery, were successfully performed. Removal was quick and complete in all cases, and lung tissue showed no remnant atelectasis.

CONCLUSIONS

The "Spacemaker" may represent a reliable alternative to current conventional techniques to facilitate minimally invasive cardiothoracic surgery. Further research is warranted to confirm the effectiveness and the safety of this device and to optimize the model before its use in humans and its introduction into clinical practice.

Robot-assisted cardiac surgery

Recognition of the significant advantages of minimizing surgical trauma has resulted in the development of minimally invasive surgical procedures. Endoscopic surgery offers patients the benefits of minimally invasive surgery, and surgical robots have enhanced the ability and precision of surgeons. Consequently, technological advances have facilitated totally endoscopic robotic cardiac surgery, which has allowed surgeons to operate endoscopically rather than through a median sternotomy during cardiac surgery. Thus, repairs for structural heart conditions, including mitral valve plasty, atrial septal defect closure, multivessel minimally invasive direct coronary artery bypass grafting (MIDCAB), and totally endoscopic coronary artery bypass graft surgery (CABG), can be totally endoscopic. Robot-assisted cardiac surgery as minimally invasive cardiac surgery is reviewed.

Elevated Stroke Risk Associated With Femoral Artery Cannulation During Mitral Valve Surgery

Minimally invasive mitral valve (MV) surgery, often requiring femoral artery (FA) cannulation, is increasingly being adopted. There is concern about increased stroke rates associated with minimally invasive MV surgery. This study aims to examine whether FA cannulation is independently associated with increased stroke rates in minimally invasive MV procedures. MV procedures from January 2004 to June 2012 were reviewed using our institutional Society of Thoracic Surgeons database. We included 384 patients after the exclusion of patients with emergency procedures, with infective endocarditis, who underwent other concomitant procedures, who were older than 60 years, and with nonstandard aortic clamping (endoballoon or no clamp). Patients were divided into 2 groups: those who underwent aortic cannulation (n = 327) and those who underwent femoral cannulation (n = 57). Risk adjustments through multivariable regression were used to identify independent predictors for various outcomes. Adjustments were made for cardiopulmonary bypass and aortic clamp times. Preoperatively, the femoral cannulation group had less baseline cerebrovascular disease (P = 0.032), heart failure (P = 0.028), and atrial fibrillation (P = 0.012). Other baseline characteristics were similar. The aortic cannulation group had shorter cardiopulmonary bypass (P < 0.001) and clamp times (P < 0.001). There were more repairs done in the FA cannulation group as opposed to replacements. Risk-adjusted outcomes showed a higher incidence of permanent stroke in the femoral cannulation group (P = 0.032). Other outcomes were not significantly different. In conclusion, FA cannulation may be associated with increased stroke rates in isolated MV surgery. Antegrade arterial cannulation (direct aortic or axillary cannulation) may be preferable in minimally invasive MV procedures. Randomized trial data are needed.

Totally thoracoscopic versus open surgery for closure of atrial septal defect: propensity-score matched comparison

The purpose of this study is to compare early clinical outcomes of surgical repair for isolated atrial septal defect (ASD) with a totally thoracoscopic approach without robotic assistance versus a conventional open procedure.Between September 2010 and June 2012, 254 consecutive patients with isolated ASD underwent totally thoracoscopic surgery without robotic assistance in seven institutions participating in the nationwide multi-centered registry in China. During the same period, these patients were matched using propensity score methodology with 254 patients who had accepted conventional open surgery through a median sternotomy. The early in-hospital results between the two groups were analyzed and compared.The patient age was 26.8 ± 14.0 years and weight was 52.9 ± 16.9 kg in the totally thoracoscopic group. The totally thoracoscopic surgery required longer aortic clamp time (32.1 ± 17.3 minutes versus 28.3 ± 16.7 minutes, P = .01); shorter length of stay in the intensive care unit (25.3 ± 12.2 hours versus 34.8 ± 24.4 hours, P = .001); shorter length of stay in hospital (6.5 ± 6.3 days versus 7.9 ± 6.4 days, P = .008); and shorter mechanical ventilation time (8.3 ± 5.0 hours versus 11.4 ± 14.8 hours, P = .04). The cardiopulmonary bypass (CPB) time (62.7 ± 29.3 minutes versus 61.5 ± 28.0 minutes, P = .64) showed no significant difference between the two groups. The totally thoracoscopic group had significantly less postoperative chest tube drainage (322.1 ± 213.7 mL versus 462.8 ± 398.4 mL, P = .001). The intraoperative (35.4% versus 38.6%, P = .46) and postoperative blood products usage (20.9% versus 21.3%, P = .91) showed no significant difference between the two groups.There also was no significant difference in mortality and major in-hospital complications between the two groups. The early outcomes for treatment of isolated ASD were similar between the totally thoracoscopic group conventional open operation performed through median sternotomy, despite a longer aortic clamp time in the totally thoracoscopic group.

Comparing the endo-aortic balloon and the external aortic clamp in minimally invasive mitral valve surgery

OBJECTIVES

The aim of this study was to assess the differences in perioperative outcomes and complications between the endo-aortic balloon (EAB) and the external aortic clamp (EAC) during primary elective minimally invasive mitral valve surgery (MIMVS) in a single referral centre by one surgeon. Primary outcomes were cardiopulmonary bypass time (CPB), cross-clamp time (CX) and occurrence of postoperative cerebrovascular accidents (CVAs). Secondary outcomes were other perioperative parameters and complications.

METHODS

We retrospectively analysed 340 consecutive patients who underwent MIMVS for mitral regurgitation (MR), mitral stenosis or combined regurgitation/stenosis between November 2010 and March 2014 in a single referral centre. In total, 221 patients who underwent an isolated mitral valve repair or isolated mitral valve replacement or repair/replacement combined with an atrial fibrillation (AF)-ablation procedure were included. Patients who had previous cardiac surgery or concomitant tricuspid valve surgery, myxoma or atrial septal defect closure surgery were excluded.

RESULTS

A total of 57 patients (Group A) underwent MIMVS using the EAC and 164 patients (Group B) were operated using an EAB. Preoperative variables showed a significant difference in poor left ventricular function (LVF, P = 0.18) and moderate LVF (P = 0.019). No significant differences were found in CPB-time, cross-clamp time or postoperative CVA. Furthermore, no significant differences were found in complications, 30-day mortality or postoperative echocardiographical MR gradation. Hospital stay, however, was prolonged in Group A (P = 0.001) and maximum troponin T levels were significantly lower in Group B (P = 0.014). In Group B however, 10 procedures were converted (6%) from EAB to EAC.

CONCLUSIONS

There is no difference in use between the EAB and the EAC in terms of CPB-time and cross-clamp time, complications or MR gradation at discharge. Use of the EAC showed significantly higher postoperative levels of troponin T, implying more myocardial damage, compared with the EAB. In 6% of the cases however, patients were converted from the EAB to the EAC.

Femoral cannulation: a safe vascular access option for cardiopulmonary bypass in minimally invasive cardiac surgery

Femoral cannulation during cardiopulmonary bypass has become a common approach for many cardiac procedures and serves as an important access option, especially during minimally invasive cardiac surgery. Opponents, however, argue that there is significant risk, including site-specific and overall morbidity, which makes the use of this modality dangerous compared to conventional aortoatrial cannulation techniques. We analyzed our institutional experience to elucidate the safety and efficacy of femoral cannulation. All data were collected from a single hospital’s cardiac surgery database. A total of 346 cardiac surgeries were evaluated from September 2012 to September 2013, of which 85/346 (24.6%) utilized a minimally invasive approach. Of the 346 operations performed, 72/346 (20.8%) utilized femoral cannulation while 274/346 (79.2%) used aortoatrial cannulation. Stroke occurred in 1/72 (1.39%) after femoral cannulation, specifically, in a conventional sternotomy patient, while it occurred in 6/274 (2.19%) [p=0.67] after aortoatrial cannulation. When comparing postoperative complications between the femoral cannulation and aortoatrial cannulation groups, the rates of atrial fibrillation [10/72 (13.9%) versus 46/274 (16.8%), p=0.55], renal failure [2/72 (2.78%) versus 11/274 (4.01%), p=0.62], prolonged ventilation time [4/72 (5.56%) versus 27/274 (9.85%), p=0.26] and re-operation for bleeding [3/72 (4.17%) versus 13/274 (4.74%), p=0.84] showed no significant difference. Selective femoral cannulation provides a safe alternative to aortoatrial cannulation for cardiopulmonary bypass and is especially important when performing minimally invasive cardiac surgery. When comparing aortoatrial and femoral cannulation, we found no significant difference in the postoperative complication rates and overall mortality.

Minimally invasive concomitant aortic and mitral valve surgery: the "Miami Method"

Valve surgery via a median sternotomy has historically been the standard of care, but in the past decade various minimally invasive approaches have gained increasing acceptance. Most data available on minimally invasive valve surgery has generally involved single valve surgery. Therefore, robust data addressing surgical techniques in patients undergoing double valve surgery is lacking. For patients undergoing combined aortic and mitral valve surgery, a minimally invasive approach, performed via a right lateral thoracotomy (the "Miami Method"), is the preferred method at our institution. This method is safe and effective and leads to an enhanced recovery in our patients given the reduction in surgical trauma. The following perspective details our surgical approach, concepts and results for combined aortic and mitral valve surgery.

Comparison of postoperative quality of life for patients who undergo atrial myxoma excision with robotically assisted versus conventional surgery

BACKGROUND

Robotically assisted cardiac surgery is an alternative to conventional, open-chest surgery. Although studies have been done on the clinical effect, morbidity, and mortality of robotically assisted atrial myxoma excision, few have addressed surgical outcomes, such as pain, quality of life (QOL), and length of sick leave from work. In this study, our aim was to evaluate these clinical variables among patients after they undergo robotically assisted atrial myxoma excision surgery.

METHODS

Between January 2007 and January 2013, a total of 93 patients underwent either conventional sternotomy or robotically assisted atrial myxoma excision in our unit. The 36-item Medical Outcomes Study Short Form Survey was used to assess the clinical outcomes in these patients postoperatively, at day 30 and 6 months.

RESULTS

The QOL scores for 7 of 8 variables in the robotically assisted group were significantly higher than those in the conventional group at postoperative day 30 (P < .05). The degree of pain and its influence on work or life was lower in the robotically assisted group (P < .05), and these patients returned to work after 0.9 ± 0.1 months, whereas those in the conventional group needed a sick leave of 3.3 ± 0.4 months.

CONCLUSIONS

The level of restoration of normal QOL within 30 days after atrial myxoma surgery is excellent with the robotically assisted approach, which may enable early return to employment and satisfactory recovery.

Anterolateral minithoracotomy versus median sternotomy for mitral valve disease: a meta-analysis

OBJECTIVE

Mitral valve disease tends to be treated with anterolateral minithoracotomy (ALMT) rather than median sternotomy (MS), as ALMT uses progressively smaller incisions to promote better cosmetic outcomes. This meta-analysis quantifies the effects of ALMT on surgical parameters and post-operative outcomes compared with MS.

METHODS

One randomized controlled study and four case-control studies, published in English from January 1996 to January 2013, were identified and evaluated.

RESULTS

ALMT showed a significantly longer cardiopulmonary bypass time (P=0.001) and aortic cross-clamp time (P=0.05) compared with MS. However, the benefits of ALMT were evident as demonstrated by a shorter length of hospital stay (P<0.00001). According to operative complications, the onset of new arrhythmias following ALMT decreased significantly as compared with MS (P=0.05); however, the incidence of peri-operative mortality (P=0.62), re-operation for bleeding (P=0.37), neurologic events (P=0.77), myocardial infarction (P=0.84), gastrointestinal complications (P=0.89), and renal insufficiency (P=0.67) were similar to these of MS. Long-term follow-up data were also examined, and revealed equivalent survival and freedom from mitral valve events.

CONCLUSIONS

Current clinical data suggest that ALMT is a safe and effective alternative to the conventional approach and is associated with better short-term outcomes and a trend towards longer survival.

Very high repair rate using minimally invasive surgery for the treatment of degenerative mitral insufficiency

BACKGROUND

Minimally invasive mitral valve surgery (MIMVS) is an established alternative to median sternotomy for mitral valve repair. However, this technique has yet to gain widespread adoption, partly because of concerns that this approach might yield lower repair rates or repairs that are less durable than those performed through a sternotomy. The purpose of this study was to report our inaugural experience with MIMVS, with a focus on mitral valve repair rate and midterm outcomes.

METHODS

Between May 2006 and April 2012, minimally invasive mitral valve repair was attempted in 200 consecutive patients with degenerative mitral disease. The approach used was a 4- to 5-cm right anterolateral minithoracotomy with femorofemoral cannulation for cardiopulmonary bypass. Mean follow-up was 2.9 ± 1.8 years, and follow-up was 99% complete.

RESULTS

The mitral valve was successfully repaired in all but 2 patients, yielding a repair rate of 99%. Hospital mortality occurred in 2 patients (1%). Intraoperative conversion to sternotomy was necessary in 12 patients (6%), including 1 of the 2 unsuccessful repairs. Mean cardiopulmonary bypass and aortic cross-clamp times were 130.8 ± 41.3 minutes and 104.8 ± 35.6 minutes, respectively. Median hospital stay was 5 days. The 5-year survival and freedom from reoperation were 97.9% ± 1.5% and 98.1% ± 1.3%, respectively.

CONCLUSIONS

A very high repair rate can be achieved using MIMVS for the treatment of degenerative mitral regurgitation, including during the learning phase. Midterm survival and freedom from valve-related reoperation are excellent. MIMVS is a safe and effective alternative to mitral valve repair through a sternotomy.

A Technical Review of Minimally Invasive Mitral Valve Replacements

Mitral regurgitation is one of the most common forms of heart valve disorder, which may result in heart failure. Due to the rapid ageing of the population, surgical repair and replacement treatments, which have represented an effective treatment in the past, are now unsuitable for about half of symptomatic patients, who are judged high-risk. Encouraged by the positive experience with transcatheter aortic valves and percutaneous reconstructive mitral treatments, a number of research groups are currently engaged in the development of minimally invasive approaches for the functional replacement of the mitral valve. The first experiences have clearly demonstrated that the approach is feasible and promising, though significant progress is still required in the prostheses design and implantation procedures before the treatment can establish as a safe and effective solution. This review analyses the devices currently at a most advanced stage of development, describing their main features and the technical solutions that they adopt in order to respond to the functional requirements of the most challenging of the heart valves.

Redo mitral valve replacement through a right mini-thoracotomy with an unclamped aorta

Redo cardiac surgery represents a clinical challenge due to a higher rate of perioperative morbidity and mortality. Mitral valve (MV) re operations can particularly be demanding in patients with patent coronary grafts, previous aortic valve replacement, calcified aorta or complications following a previous operation (abscesses, leaks or thrombosis). In this article we describe our technique to manage complex mitral reoperations using a minimally invasive approach, moderate hypothermia and avoiding aortic cross-clamping. Minimally invasive procedures with an unclamped aorta have the potential to combine the benefits of less invasive access and continuous myocardial perfusion. The advantage of a right mini-thoracotomy is the avoidance of sternal re-entry and limited dissection of adhesions, reducing the risk of cardiac structures or patent graft injury. Moderate hypothermia and continuous blood perfusion can guarantee adequate myocardial protection particularly in the case of patent grafts, decreasing the dangers of an incomplete or imperfect aortic clamping at mild hypothermia and potential lesions due to demanding clamp placing. Complex MV reoperations can be safely and effectively performed through a smaller right thoracotomy in the fourth intercostal space with an unclamped aorta.

Mitral durability after robotic mitral valve repair: analysis of 200 consecutive mitral regurgitation repairs

OBJECTIVES

The study objective was to review a single-center experience on robotic mitral valve repair to treat mitral regurgitation, with a specific focus on midterm echocardiographic mitral durability. No data assessing the quality or durability of repaired mitral valves are currently available.

METHODS

A total of 200 patients who underwent robotic mitral regurgitation repair using the da Vinci system (Intuitive Surgical, Inc, Sunnyvale, Calif) between August 2007 and December 2012 were evaluated. Serial echocardiographic results and operative and procedural times were analyzed.

RESULTS

Mitral regurgitation repairs were successfully performed, and no or mild residual mitral regurgitation developed in 98.0% of patients, with no conversion to sternotomy. No in-hospital deaths occurred. Follow-up was completed in 96.5% of patients with a median of 31.4 months (interquartile range, 12.4-42.3 months). During follow-up, 4 late deaths, 2 strokes, 1 low cardiac output, 1 newly required dialysis, and 1 reoperation for mitral regurgitation occurred. Freedom from major adverse cardiac events at 5 years was 87.7% ± 5.1%. Regular echocardiographic follow-up (>6 months) was achieved in 187 patients (93.5%). At a median of 29.6 months (interquartile range, 14.9-45.8 months), 21 patients (10.5%) demonstrated moderate or greater mitral regurgitation. Freedom from moderate or greater mitral regurgitation at 5 years was 87.0% ± 2.6%. Mean cardiopulmonary bypass and crossclamping times were 182.9 ± 48.4 minutes and 110.9 ± 34.1 minutes, respectively, demonstrating a significant decrease in both times according to the chronologic date of surgery.

CONCLUSIONS

Robotic mitral regurgitation repair is technically feasible and efficacious, demonstrating favorable midterm mitral durability and improved procedural times as experience increases.

Aortic valve replacement and concomitant right coronary artery bypass grafting performed via a right minithoracotomy approach

OBJECTIVE

We present our experience of concomitant right coronary artery bypass grafting (CABG) and aortic valve replacement performed via a right minithoracotomy in patients with coronary lesions not amenable to percutaneous intervention.

METHODS

A total of 17 patients underwent concomitant aortic valve replacement and right CABG between April 2008 and July 2013. A 5- to 6-cm minithoracotomy incision was made over the right second or third intercostal space, and the costochondral cartilage was transected. A saphenous vein bypass to the right coronary artery was then performed, initiating the anastomosis from the toe of the graft. Subsequently, the aortic valve was replaced using standard techniques.

RESULTS

There were 6 men and 11 women. The median European System for Cardiac Operative Risk Evaluation II score mortality risk was 5% [interquartile range (IQR), 2%-8%]. The mean (SD) age was 77 (10) years, the left ventricular ejection fraction was 59% (8%), and the New York Heart Association functional class was 2.4 (0.8). One patient had a history of CABG. The mean (SD) cardiopulmonary bypass time was 168 (57) minutes, and the aortic cross-clamp time was 133 (36) minutes. Three patients underwent concomitant mitral valve surgery (replacement, 2; repair, 1). The median intensive care unit and hospital lengths of stay were 47 hours (IQR, 24-90) and 9 days (IQR, 5-13), respectively. There was one reoperation for bleeding, and there was one postoperative stroke. All patients were alive at a mean (SD) follow-up of 2 (1.1) years.

CONCLUSIONS

Aortic valve replacement with concomitant CABG performed via a right minithoracotomy approach is feasible.

Review of mitral valve insufficiency: repair or replacement

Mitral valve (MV) dysfunction is the second-most common clinically significant form of valvular defect in adults. MV regurgitation occurs with the increasing frequency of degenerative changes of the aging process. Moreover, other causes of clinically significant MV regurgitation include cardiac ischemia, infective endocarditis and rhematic disease more frequently in less developed countries. Recent evidence suggests that the best outcomes after repair of severe degenerative mitral regurgitation (MR) are achieved in asymptomatic or minimally symptomatic patients, who are selected for surgery soon after diagnosis on the basis of echocardiography. This review will focus on the surgical management of mitral insufficiency according to its aetiology today and will give insight to some of the perspectives that lay in the future.

A meta-analysis of minimally invasive versus conventional mitral valve repair for patients with degenerative mitral disease

BACKGROUND

Minimally invasive mitral valve surgery through a mini-thoracotomy approach was developed in the mid-1990s as an alternative to conventional sternotomy, but with reduced trauma and quicker recovery. However, technical demands and a paucity of comparative data have thus far limited the widespread adoption of minimally invasive mitral valve repair (MIMVR). Previous meta-analyses have grouped various surgical techniques and underlying valvular disease aetiologies together for comparison. The present study aimed to compare the clinical outcomes of MIMVR versus conventional mitral valve repair in patients with degenerative mitral valve disease.

METHODS

A systematic review of the current literature was performed through nine electronic databases from January 1995 to July 2013 to identify all relevant studies with comparative data on MIMVR versus conventional mitral valve surgery. Measured endpoints included mortality, stroke, renal failure, wound infection, reoperation for bleeding, aortic dissection, myocardial infarction, atrial fibrillation, readmission within 30 days, cross clamp time, cardiopulmonary bypass time and durations of intensive care unit (ICU) stay and overall hospitalization. Echocardiographic outcomes were also assessed when possible.

RESULTS

Seven relevant studies were identified according to the predefined study selection criteria, including one randomized controlled trial and six retrospective studies. Meta-analysis of clinical outcomes did not identify any statistically significant differences between MIMVR and conventional mitral valve repair. The duration of ICU stay was significantly shorter for patients who underwent MIMVR, but this did not translate to a shorter hospitalization period. Patients who underwent MIMVR required longer cross clamp time as well as cardiopulmonary bypass time. Both surgical techniques appeared to achieve satisfactory echocardiographic outcomes. Pain-related outcomes was assessed in one study and reported significantly less pain for patients who underwent MIMVR. However, this limited data was not suitable for meta-analysis.

CONCLUSIONS

The existing literature has limited data on comparative outcomes after MIMVR versus conventional mitral valve repair for patients with degenerative disease. From the available evidence, there are no significant differences between the two surgical techniques in regards to clinical outcomes. Patients who underwent MIMVR required longer cardiopulmonary bypass and cross clamp times, but the duration of stay in the ICU was significantly shorter than conventional mitral valve repair.

Minimally invasive approach for redo mitral valve surgery

Redo cardiac surgery represents a clinical challenge due to a higher rate of peri-operative morbidity and mortality. Mitral valve re-operations can be particularly demanding in patients with patent coronary artery bypass grafts, previous aortic valve replacement, calcified aorta or complications following a previous operation (abscesses, perivalvular leaks, or thrombosis). Risk of graft injuries, hemorrhage, the presence of dense adhesions and complex valve exposure can make redo valve operations challenging through a median sternotomy. In this review article we provide an overview of minimally invasive approaches for redo mitral valve surgery discussing indications, techniques, outcomes, concerns and controversies. Scientific literature about minimally invasive approach for redo mitral surgery was reviewed with a MEDLINE search strategy combining "mitral valve" with the following terms: 'minimally invasive', 'reoperation', and 'alternative approach'. The search was limited to the last ten years. A total of 168 papers were found using the reported search. From these, ten papers were identified to provide the best evidence on the subject. Mitral valve reoperations can be safely and effectively performed through a smaller right thoracotomy in the fourth intercostal space termed "mini" thoracotomy or "port access". The greatest potential benefit of a right mini-thoracotomy is the avoidance of sternal re-entry and limited dissection of adhesions, avoiding the risk of injury to cardiac structures or patent grafts. Good percentages of valve repair can be achieved. Mortality is low as well as major complications. Minimally invasive procedures with an unclamped aorta have the potential to combine the benefits of minimally invasive access and continuous myocardial perfusion. Less invasive trans-catheter techniques could be considered as the natural future evolution for management of structural heart disease and mitral reoperations. The safety and efficacy of these procedures has never been compared to open reoperations in a randomized trial, although published case series and comparisons to historical cohorts suggest that they are an effective and feasible alternative. Ongoing follow-up on current series will further define these procedures and provide valuable clinical outcome data.

Minimally invasive mitral surgery through right mini-thoracotomy under direct vision

In the 1990s, the success of 'minimally invasive' laparoscopic operations in other surgical subspecialties sparked an interest in minimally-invasive approaches for cardiac surgery, specifically for mitral valve repair. In 1996 at New York University (NYU) we began our experience with minimally invasive mitral valve repair performed through a small right anterior mini-thoracotomy incision using the Port-Access system in a phase I clinical trial. This was the beginning of our extensive right mini-thoracotomy experience for mitral valve repair at NYU. Currently at our institution the preferred approach for the right mini-thoracotomy mitral valve surgery is through the 3rd or 4th interspace mini-thoracotomy incision. Perfusion is accomplished with direct aortic or femoral cannulation, long femoral venous cannula drainage, and a retrograde cardioplegia catheter placed trans-atrialy in the coronary sinus under TEE guidance. An antegrade cardioplegia and venting needle is placed in the ascending aorta and direct external aortic clamping is achieved with one of several specialized crossclamps. With over four decades of experience, more than 4,000 patients have undergone mitral valve repair at NYU including 1,922 performed through a right mini-thoracotomy. We have reported an overall operative mortality of 1.3%, 8-year freedom from reoperation of 95%, freedom from reoperation or severe recurrent mitral regurgitation of 93%, and freedom from all valve-related complications of 90% for our initial series of 1,071 right mini-thoracotomy mitral valve repair. Based on our extensive experience we believe that mitral valve repair through a right mini-thoracotomy provides a durable and safe alternative to a traditional sternotomy with the benefits of improved cosmesis, reduced post-operative pain, less blood loss with fewer blood transfusions, fewer infections, shorter length of stay, and faster return to activity. It is our standard of care approach for mitral valve surgery.

Robotically assisted minimally invasive mitral valve surgery

Increased recognition of advantages, over the last decade, of minimizing surgical trauma by operating through smaller incisions and its direct impact on reduced postoperative pain, quicker recovery, improved cosmesis and earlier return to work has spurred the minimally invasive cardiac surgical revolution. This transition began in the early 1990s with advancements in endoscopic instruments, video & fiberoptic technology and improvements in perfusion systems for establishing cardiopulmonary bypass (CPB) via peripheral cannulation. Society of Thoracic Surgeons data documents that 20% of all mitral valve surgeries are performed using minimally invasive techniques, with half being robotically assisted. This article reviews the current status of robotically assisted mitral valve surgery, its advantages and technical modifications for optimizing clinical outcomes.

Hybrid approach of percutaneous coronary intervention followed by minimally invasive valve operations

BACKGROUND

A subset of patients requiring coronary revascularization and valve operations may benefit from a hybrid approach of percutaneous coronary intervention (PCI) followed by a minimally invasive valve operation, rather than the standard combined median sternotomy coronary artery bypass grafting (CABG) and a valve operation. This study sought to evaluate the outcomes of this approach in a heterogeneous group of patients with concomitant coronary artery and valvular disease.

METHODS

We retrospectively evaluated 222 consecutive patients with coronary artery and valvular heart disease who underwent PCI followed by elective minimally invasive valve operations at our institution between February 2009 and August 2013.

RESULTS

A total of 136 men and 86 women were identified. The mean age was 74.6 ± 8.2 years, with 181 (81.5%) undergoing 1-vessel, 27 (12.2%) undergoing 2-vessel, and 14 (6.3%) undergoing 3-vessel PCI. Within a median of 38 days (interquartile range [IQR] 18-65 days), 182 (82%) patients underwent primary and 34 (15.3%) underwent repeated valve operations, which consisted of 185 (83.3%) single-valve and 37 (16.7%) double-valve procedures. Operative mortality occurred in 8 patients (3.6%). At a mean follow-up of 16.2 ± 12 months, 6 patients required PCI, with target-vessel revascularization performed in 4 patients (2.1%). Survival at 1 and 4.5 years was 91.9% and 88.3%, respectively.

CONCLUSIONS

In a heterogeneous group of patients, a hybrid approach of PCI followed by minimally invasive valve operations in patients undergoing primary or repeated valve operations can be performed with excellent outcomes.

Mitral valve repair in a patient with an anomalous left coronary artery

Anomalous coronary arteries may course in close proximity to the mitral annulus, which increases the risk of iatrogenic occlusion due to annular suture placement. We report a mitral valve repair in a 55-year-old male with severe mitral regurgitation and an anomalous retro-aortic left coronary artery, originating from the right coronary sinus, coursing in close proximity to the anterior mitral annulus. To minimize iatrogenic occlusion risk an open annuloplasty ring was used with good long-term results.

Minimally invasive valve surgery

Cardiac valve surgery is life saving for many patients. The advent of minimally invasive surgical techniques has historically allowed for improvement in both postoperative convalescence and important clinical outcomes. The development of minimally invasive cardiac valve repair and replacement surgery over the past decade is poised to revolutionize the care of cardiac valve patients. Here, we present a review of the history and current trends in minimally invasive aortic and mitral valve repair and replacement, including the development of sutureless bioprosthetic valves.

Minimally invasive procedures - direct and video-assisted forms in the treatment of heart diseases

BACKGROUND

Minimally invasive cardiovascular procedures have been progressively used in heart surgery.

OBJECTIVE

To describe the techniques and immediate results of minimally invasive procedures in 5 years.

METHODS

Prospective and descriptive study in which 102 patients were submitted to minimally invasive procedures in direct and video-assisted forms. Clinical and surgical variables were evaluated as well as the in hospital follow-up of the patients.

RESULTS

Fourteen patients were operated through the direct form and 88 through the video-assisted form. Between minimally invasive procedures in direct form, 13 had aortic valve disease. Between minimally invasive procedures in video-assisted forms, 43 had mitral valve disease, 41 atrial septal defect and four tumors. In relation to mitral valve disease, we replaced 26 and reconstructed 17 valves. Aortic clamp, extracorporeal and procedure times were, respectively, 91,6 ± 21,8, 112,7 ± 27,9 e 247,1 ± 20,3 minutes in minimally invasive procedures in direct form. Between minimally invasive procedures in video-assisted forms, 71,6 ± 29, 99,7 ± 32,6 e 226,1 ± 42,7 minutes. Considering intensive care and hospitalization times, these were 41,1 ± 14,7 hours and 4,6 ± 2 days in minimally invasive procedures in direct and 36,8 ± 16,3 hours and 4,3 ± 1,9 days in minimally invasive procedures in video-assisted forms procedures.

CONCLUSION

Minimally invasive procedures were used in two forms - direct and video-assisted - with safety in the surgical treatment of video-assisted, atrial septal defect and tumors of the heart. These procedures seem to result in longer surgical variables. However, hospital recuperation was faster, independent of the access or pathology.

Minimally invasive mitral valve surgery utilizing heart port technology

OBJECTIVE

To determine operative outcomes of right mini-thoracotomy mitral valve surgery utilizing port access technology in first-time and reoperative cardiac surgery patients.

METHODS

From 2002 to 2011, 881 patients underwent minimally invasive mitral valve surgery. Of these, 154 patients had previous cardiac operations via sternotomy (Group 1), of which 18 (12%) had two previous operations. Seven hundred and twenty-seven patients had no previous cardiac operations (Group 2).

RESULTS

Patient demographics were similar in both groups. In Group 1, 76 (49%) patients had previous coronary artery bypass grafting, 13 (8%) had previous aortic valve surgery, and 57 (37%) had previous mitral valve surgery. Preoperative echo findings for Groups 1 and 2 included severe mitral regurgitation (MR) (88%, n = 135; 94%, n = 687), mitral stenosis (MS) (4%, n = 6; 2%, n = 12), MS + MR (8%, n = 13; 4%, n = 28), and ejection fraction (48%, 56%). Operative procedures in Groups 1 and 2 were MV repair (54%, n = 84; 89%, n = 645) and MV replacement (46%, n = 70; 11%, n = 82). Circulatory management techniques for Groups 1 and 2 included endoballoon (75%, n = 116; 79%, n = 576), Chitwood clamp (8%, n = 12; 20%, n = 147), and fibrillatory arrest (17%, n = 30; 0.5%, n = 4). Perioperative outcomes were: stroke: 2.5%, 1.6%; reoperation for bleeding: 5%, 6%; valvular reoperation rate: 0.6%, 2%; aortic dissection: 2.5%, 1%; and wound infection: 0%, 0%. Transfusion requirement was 49% (n = 76) and 31% (n = 232), respectively. Median hospital stay was seven and seven days, respectively. On postoperative echocardiography, 98% (n = 151) and 99% (n = 718) of patients had zero or trace MR (1+) with 100% freedom from MR > 2+. In-hospital mortality was 3% (n = 5) and 1% (n = 8).

CONCLUSIONS

Operative outcomes with minimally invasive mitral valve surgery utilizing port access technology can be performed safely. Stroke rate was higher in the reoperative cases (p = NS) although similar to reports evaluating redo sternotomy in mitral valve cases.

Video-assisted minimally invasive mitral valve surgery: transitioning from sternotomy to mini-thoracotomy

Minimally invasive right thoracotomy approaches to complex mitral valve surgery have emerged as safe and effective alternatives to traditional median sternotomy. Early experiences were associated with concerns over repair failures, neurological events and longer cardiopulmonary bypass times. However, several technique refinements over the last decade have led to a resurgence of minimally invasive thoracotomy/thoracoscopic mitral surgery with improved short-term outcomes and equivalent long-term durability to sternotomy. We describe one such approach that utilizes video assistance along with direct vision to facilitate reproducible mitral surgery.

Experience with a minimally invasive approach to combined valve surgery and coronary artery bypass grafting through bilateral thoracotomies

BACKGROUND

Minimally invasive coronary artery bypass grafting (MICS-CABG) and minimally invasive valve surgery (MIVS) have been used independently to manage occlusive coronary artery disease and valvular diseases, respectively. We present 12 patients who underwent combined MICS-CABG and MIVS via bilateral mini-thoracotomies.

METHODS

We retrospectively reviewed 116 consecutive valve/CABG operations by a single surgeon and compared the outcomes obtained via sternotomy with those obtained via bilateral minithoracotomies.

RESULTS

Six patients in the MIVS group underwent aortic valve replacement (sternotomy group, n = 70), 3 patients underwent mitral valve repair (sternotomy group, n = 9), and 3 underwent mitral valve replacement (sternotomy group, n = 25). The minimally invasive valve surgeries were combined with MICS-CABG for single- (n = 2), double- (n = 9), and triple-vessel (n = 1) coronary artery disease in a single operation. The mean SD duration of cardiopulmonary bypass was 164 ± 44.6 minutes (mean time via sternotomy, 152 ± 50.5 minutes; P = .4146), and the mean aortic cross-clamp time was 87.8 ± 22.1 minutes (mean time via sternotomy, 105 ± 39.8 minutes; P = .1455). The use of perioperative blood transfusions averaged to 2.3 ± 5.6 units (mean usage via sternotomy, 2.7 ± 4.9 units; P = .8326). There were no conversions to sternotomy in the minimally invasive group. Patients in the minimally invasive group were extubated earlier (24 ± 11 hours; sternotomy group, 40 ± 61 hours; P = .3684) and discharged earlier (7 ± 4 days) than patients who underwent median sternotomy (9 ± 10 days; P = .4027).

CONCLUSION

MICS-CABG combined with MIVS via bilateral minithoracotomies yielded short-term results comparable to those for CABG and valve repair via median sternotomy. There were no operative mortalities or reoperations. The possible advantages of the minimally invasive approach included earlier extubation and earlier discharge from the hospital. Combined CABG and valve surgery can be safely performed via bilateral thoracotomies.