Minimal access reoperative mitral and aortic valve surgery

Minimally invasive reoperative aortic valve replacement: a systematic review and meta-analysis

BACKGROUND

With prolonged life expectancy and more frequent use of biological prostheses, an increasingly higher proportion of patients are undergoing aortic valve replacement (AVR) after previous sternotomy. We critically appraised the quantity and quality of evidence to demonstrate the efficacy and safety of the minimally invasive (MIrAVR) versus conventional (CrAVR) approaches for reoperative AVR.

METHODS

Electronic searches were performed using six databases from their inception to April 2014. Relevant studies utilizing a MIrAVR were identified. Data were extracted and analyzed according to predefined clinical endpoints.

RESULTS

Four single-arm and seven comparative observational studies including a total of 441 MIrAVR patients were included for quality assessment, data extraction and analysis. In-hospital mortality ranged from 0-9.5%, and was similar between the MIrAVR and CrAVR groups (RR, 0.77; 95% CI, 0.39-1.54; P=0.46). Stroke rates ranged from 2.6-8% and were also similar between the two cohorts. The rates of pacemaker implantation, renal failure and reoperation for bleeding were not significantly different between the two groups. There were no reports of myocardial infarctions in the included studies. No significant difference in hospital stay was observed for the MIrAVR versus CrAVR group.

CONCLUSIONS

The current literature suggests that MIrAVR has similar efficacy and mortality outcomes compared to CrAVR without compromise to myocardial protection or hospitalization duration. It appears to be a valid alternative option for patients requiring reoperative AVR.

Is a minimally invasive approach for re-operative aortic valve replacement superior to standard full resternotomy?

A best-evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'is a minimally invasive approach for re-operative aortic valve replacement (AVR) superior to standard full resternotomy?' A total of 193 papers were found using the reported search of which 13 represented the best evidence to answer the clinical question. The authors, country, journal and date of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that minimally invasive re-operative AVR can be performed with an operative morbidity and mortality at least similar to the standard full sternotomy approach. A shorter hospital length of stay and less blood product requirements are the main advantages of this technique. The incidence of prolonged ventilation, bleeding requiring re-operation, sternal wound infections and in-hospital mortality may be reduced with a minimally invasive approach. Prospective studies are required to confirm the potential benefits of minimally invasive surgery and, up to date, conventional full re-sternotomy is still the standard approach for re-operative AVR.

Minimally invasive valve surgery: different techniques and approaches

Less invasive approaches to cardiac surgical procedures are being developed in an effort to decrease patient morbidity and enhance postoperative recovery in comparison with conventional methods. Although full median sternotomy has been the standard surgical approach to the heart for more than 30 years, minimally invasive techniques using limited incisions are rapidly gaining acceptance. Potential advantages of a small skin incision include less trauma and tissue injury, leading to a less painful and quicker overall recovery, as well as shorter hospital stays for patients. Decreasing the size of the skin incision for minimally invasive valve surgery to significantly less than the cardiac size requires specific access to the valve to be repaired or replaced. Thus, various minimally invasive techniques and approaches have been described for aortic and mitral valve surgery. This article will review the different minimally invasive techniques and approaches, as well as early results and outcomes for aortic and mitral valve surgery.

Minimally invasive technology for mitral valve surgery via left thoracotomy: experience with forty cases

BACKGROUND

Recent evolution of minimally invasive technology has expanded the application of the right thoracotomy approach for mitral valve surgery. These same technological advances have also made the left posterior minithoracotomy approach attractive in complex mitral procedures.

METHODS

From 1996 to 2003, 921 isolated mitral valve procedures were performed without sternotomy; 40 (4.3%) of these were performed via left posterior minithoracotomy. In the left posterior minithoracotomy group, ages ranged from 18 to 84 years; 36 patients had had previous cardiac surgery (9 on > or =2 occasions). Other factors precluding right thoracotomy included mastectomy/radiation and pectus excavatum.

RESULTS

Arterial perfusion was via femoral artery (n = 26) or descending aorta (n = 14); long femoral venous cannulas with vacuum-assisted drainage were used in 39 procedures. Two patients had direct aortic crossclamping, 18 had hypothermic fibrillation, and 20 had balloon endoaortic occlusion. The mean crossclamp and bypass times were 81.9 and 117.2 minutes, respectively. Hospital mortality was 5.0% (2/40); both deaths occurred in octogenarians. There were no injuries to bypass grafts or conversions to sternotomy. Complications included perioperative stroke (2/40; 5.0%), bleeding (2/40; 5.0%), and respiratory failure (1/40; 2.5%); 28 patients (70%) had no postoperative complications. There was no incidence of perioperative myocardial infarction, renal failure, sepsis, or wound infection. The median length of stay was 7 days.

CONCLUSIONS

Advances in minimally invasive cardiac surgery technology are readily adaptable to a left-sided minithoracotomy approach to the mitral valve. The left posterior minithoracotomy approach is a valuable option in complicated reoperative mitral procedures with acceptable perioperative morbidity and mortality.