2. Literature search
Medline, EMBASE databases, and the Cochrane Library were searched from 1992 (date of first David procedure performed) to December 2021 by a librarian. Eligible studies were identified using various combinations of Medical Subject Headings and keywords in the abstract or title: valve-sparing aortic root replacement, David procedure, minimally invasive cardiac surgery, (upper) hemisternotomy. Six retrospective nonrandomized studies from 5 different centers were identified including a total of 250 patients operated via minimal access. Ethics Committee approval was not required as this is a review manuscript. Case reports, conference papers or abstracts and studies not published in languages other than English were excluded.
Patient selection and preoperative assessment
Recent evidence demonstrates that patient selection plays important role in the long-term outcomes of the David procedure in both conventional and minimally invasive access.5, 10, 13 Several centers reported how they started performing minimally invasive David procedure in carefully selected elective patients after having experience in performing David procedure via conventional sternotomy.10-13,15 In addition, a few studies emphasized the importance of developing fundamental skillset and having experience in minimally invasive AVR beforehand due to the challenges of the learning-curve.10,11,13
Shrestha and colleagues reported that they have initially performed minimally invasive David procedure in relatively young patients (<60 years) with isolated aortic root aneurysm, no significant co-morbidities, and AR without leaflet calcifications.10 Furthermore, excellent initial outcomes have encouraged performing minimally invasive David procedure in all elective patients with isolated aortic root aneurysm.13 However, minimally invasive access was generally not considered in patients with previous sternotomy and those requiring additional concomitant procedures (coronary bypass, valve surgery).10 A very deep aortic root might represent an anatomical contraindication for minimally invasive access. Still, the final decision whether to proceed with a valve-sparing technique was made by the surgeon intraoperatively after the assessment of AV using transesophageal echocardiography (TOE) and direct inspection.10,13,24
Preoperative work-up is another important aspect for performing minimally invasive David procedure safely.10,13 In addition to routine preoperative assessment, echocardiography, computed tomography scan of aorta and coronary angiography (age >40 years) are required.10,13,24