Minimal Access Aortic Valve Surgery

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

A Simple Approach for Minimally Invasive Combined Aortic and Mitral Valve Surgery

BACKGROUND

 There is now extension of minimally invasive techniques to involve concomitantly aortic and mitral valves through a single small incision. We share our experience in such surgeries through upper partial sternotomy with approaching the mitral valve through the dome of the left atrium.

METHODS

 Two matched groups of cases receiving concomitant aortic and mitral valve surgeries are compared regarding the surgical outcomes: the minimally invasive group (group A) including 72 patients and the conventional group (group B) including 78 patients.

RESULTS

 The mean age was 52 ± 8 years in group A and 53 ± 7 years in group B. Males represented (42%) in group A and (49%) in group B. The mean mechanical ventilation time was significantly shorter in group A (4.3 ± 1.2 hours) than in group B (6.1 ± 0.8 hours) with a p-value of 0.001. In addition, the amount of chest tube drainage and the need for blood transfusion units were significantly less in group A (250 ± 160 cm³ and 1.3 ± 0.8 units, respectively) when compared with group B (320 ± 180 cm³ and 1.8 ± 0.9 units, respectively) with p-values of 0.013 and 0.005, respectively. Over a follow-up period of 3.2 ± 1.1 years, one mortality occurred in each group with no significant difference (p-value = 0.512).

CONCLUSION

 Combined aortic and mitral valve surgery through upper partial sternotomy with approaching the mitral valve through the dome of the left atrium is safe and effective with the advantages of less postoperative blood loss, need for blood transfusion, and mechanical ventilation time compared with conventional aortic and mitral valve surgery.

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

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

Quantitating Mitral Regurgitation in Clinical Trials: The Need for a Uniform Approach

BACKGROUND

There is an established relationship between the degree of mitral regurgitation (MR) and prognosis. Quantitation of MR severity guides therapeutic approaches. Inconsistent definitions and categorization of MR severity in clinical studies limit meaningful comparisons between trials and compromise development of an effective evidence base. The purpose of this study was to quantify heterogeneity in grading systems for MR severity in the contemporary literature.

METHODS

We performed a systematic review of randomized (RCT) and propensity score (PS) adjusted clinical studies of MV interventions (surgical or percutaneous). A total of 35 articles from 2015-2020 were included (15 RCT, 20 PS).

RESULTS

There were 22 studies that reported MR severity in numerical categories, either values from the historical "plus" system or numerical MR grades, while 9 studies reported MR severity using text-only descriptive categories. Among the studies that used numerical categories, 2+ MR was defined as moderate in 64% of studies, mild in 27%, and mild-moderate in 9% and 3+ MR was defined as moderate in 14%, moderate-severe in 52%, and severe in 14%.

CONCLUSIONS

There was substantial variability in MR severity definition and reporting in contemporary clinical studies of MV interventions. We recommend the historical "plus" numerical grading system be abandoned and that inclusion and outcome criteria in MR clinical trials be based on American and European guideline-recommended categories as none/trace, mild, moderate, and severe. Adoption of these simple recommendations will improve the consistency and quality of MR clinical trial design and reporting.

Right Mini-Thoracotomy for Aortic Plus Mitral with or without Tricuspid Valve Surgery

OBJECTIVES

 Minimally invasive surgery is increasingly performed for isolated aortic or mitral valve procedures. However, combined minimally invasive aortic and mitral valve surgery is rare. We report our initial experience performing multiple valve procedures through a right-sided mini-thoracotomy (RMT) compared with sternotomy.

METHODS

 A total of 264 patients underwent aortic and mitral with or without tricuspid valve surgery through RMT (n = 25) or sternotomy (n = 239). Propensity score matching was used for outcome comparisons.

RESULTS

 Of the 264 patients, 25 (age: 72 ± 10 years; 72% male) underwent double (n = 19) and triple valve surgery (n = 6) through RMT and 239 (age: 71 ± 11 years; 54% male) underwent double (n = 176) and triple valve surgery (n = 63) through sternotomy. Sternotomy patients had more co-morbidities and preoperative risk factors (EuroSCORE II 10.25 ± 10.89 vs. RMT 3.58. ± 4.98; p < 0.001). RMT procedures were uneventful without intraoperative complications or conversions to sternotomy. After propensity score matching, surgical procedures were comparable between groups with a higher valve repair rate in RMT. Despite longer cardiopulmonary bypass times in RMT, there was no evidence for differences in 30-day mortality (RMT: n = 2 vs. sternotomy: n = 2) and there were no significant differences in other outcomes. During 5-year follow-up, reoperation was required in sternotomy patients only (n = 2). Follow-up echocardiography showed durable results after valve surgery. RMT patients showed higher survival probability compared with sternotomy, although this difference was not significant (hazard ratio = 0.33; 95% confidence interval: 0.06-1.65; p = 0.18).

CONCLUSION

 Combined aortic plus mitral with or without tricuspid valve surgery can safely be performed through a RMT with a trend toward better mid-term outcomes.

First Experiences with MANTA Vascular Closure Device in Minimally Invasive Valve Surgery

BACKGROUND

 To more minimize the minimally invasive valve surgeries, percutaneous vascular access and closure has been used for the establishment of extracorporeal circulation. This study investigates early clinical outcomes of patients who received MANTA for femoral artery closure as first experiences in minimally invasive valve surgery.

METHODS

 Between January 2019 and July 2019, 103 consecutive patients (mean age: 58 ± 11 years) underwent video-assisted minimally invasive valve surgery through right anterior minithoracotomy at two cardiac surgery referral centers in Germany. Percutaneous cannulation for cardiopulmonary bypass and femoral artery closure with MANTA were performed in all patients: 18-F and 14-F MANTA were used in 88 (85.4%) and 15 (14.6%) patient, respectively. Mitral, aortic, tricuspid, and double valve surgeries were performed in 51 (49.5%), 39 (37.9%), 7 (6.8%), and 6 (5.8%), patients, respectively. Clinical data were prospectively entered into our institutional database.

RESULTS

 Cardiopulmonary bypass time and cross-clamping time were 69 ± 23 and 38 ± 14 minutes, respectively. Except for two patients with late pseudoaneurysm on 15th and 23th postoperative day, neither major nor minor vascular complications nor vascular closure device failure according to the Valve Academic Research Consortium-2 definition criteria was observed. Additionally, no wound healing disorders or conversion to surgical closure was observed.

CONCLUSIONS

 MANTA as percutaneous femoral artery closure after decannulation of cardiopulmonary bypass is a safe, feasible, and effective approach and yields excellent early outcomes. Larger size studies are needed to evaluate more the efficacy and safety of MANTA.

Outcomes in minimally invasive double valve surgery

OBJECTIVE

To review current literature evidence on outcomes of minimally invasive double valve surgeries (MIS).

METHODS

A comprehensive electronic literature search was done from inception to 20th June 2020 identifying articles that discussed outcomes of minimally invasive approach in double valve surgeries either as a solo cohort or as comparative to conventional sternotomies. No limit was placed on time and place of publication and the evidence has been summarized in narrative manner within the manuscript.

RESULTS

Majority of current literature reported similar perioperative and clinical outcomes between MIS and conventional median sternotomy; except that MIS has better cosmetic effects and pain control. Nevertheless, minimal invasive techniques are associated with longer cardiopulmonary bypass and aortic cross-clamp times which may have impact on the reported outcomes and overall morbidity and mortality rates.

CONCLUSION

Minimally invasive double valve surgery continues to develop, but scarcity in the literature suggests uptake is slow, possibly due to the learning curve associated with MIS. Many outcomes appear to be comparable to conventional sternotomy. There is need for larger, multi-center, and randomized trial to fully evaluate and establish the early, mid- and long-term morbidity and mortality rates associated with both techniques.

Comparison of outcomes between minimally invasive and median sternotomy for double and triple valve surgery: A meta-analysis

BACKGROUND

Limited data exists demonstrating the efficacy of minimally invasive surgery (MIS) compared to median sternotomy (MS) for multiple valvular disease (MVD). This systematic review and meta-analysis aims to compare operative and peri-operative outcomes of MIS vs MS in MVD.

METHODS

PubMed, Ovid, and Embase were searched from inception until August 2019 for randomized and observational studies comparing MIS and MS in patients with MVD. Clinical outcomes of intra- and postoperative times, reoperation for bleeding and surgical site infection were evaluated.

RESULTS

Five observational studies comparing 340 MIS vs 414 MS patients were eligible for qualitative and quantitative review. The quality of evidence assessed using the Newcastle-Ottawa scale was good for all included studies. Meta-analysis demonstrated increased cardiopulmonary bypass time for MIS patients (weighted mean difference [WMD], 0.487; 95% confidence interval [CI], 0.365-0.608; P < .0001). Similarly, aortic cross-clamp time was longer in patients undergoing MIS (WMD, 0.632; 95% CI, 0.509-0.755; P < .0001). No differences were found in operative mortality, reoperation for bleeding, surgical site infection, or hospital stay.

CONCLUSIONS

MIS for MVD have similar short-term outcomes compared to MS. This adds value to the use of minimally invasive methods for multivalvular surgery, despite conferring longer operative times. However, the paucity in literature and learning curve associated with MIS warrants further evidence, ideally randomized control trials, to support these findings.