There were 26 included studies (n=4,891 patients): four RCTs, five prospective and 17 retrospective non-randomised controlled studies. Four of the non-randomised studies were classified as high quality.
There was a small difference in perioperative mortality in favour of minimal access aortic valve replacement in the overall meta-analysis (20 studies) but this was not robust when study quality was taken into account (OR 0.73, 95% CI 0.43 to 1.25; six studies).
There was a statistically significant difference in favour of minimal access aortic valve replacement in the number of days spent in intensive care unit (ICU), total length of hospital stay and ventilation time. There was statistically significant heterogeneity in all three analyses but the findings were robust in the sensitivity analysis and heterogeneity was reduced: ICU stay (WMD -0.39 days, 95% CI -0.67 to -0.11); length of hospital stay (WMD -0.67 days, 95% CI -1.08 to -26); number of hours ventilation (OR -1.02, 95% CI -1.66 to -0.38).
There were no statistically significant differences between minimal access aortic valve replacement and conventional aortic valve replacement for the other primary outcomes cerebrovascular accident, renal failure and respiratory failure. Eighteen other outcomes were assessed.
There was a benefit with conventional aortic valve replacement for length of cardiopulmonary bypass and total operative time that was robust to sensitivity analysis but there were no other differences between the groups.