Minimally invasive versus conventional mitral valve surgery: a systematic review and meta-analysis of randomised clinical trials.

BACKGROUND

The benefits of minimally invasive mitral valve surgery (MIMVS) compared with conventional approaches (CMVS, conventional mitral valve surgery) remain controversial. We conducted a systematic review and meta-analysis to evaluate the short-term benefits between these approaches.

OBJECTIVE

To evaluate the short-term benefits of MIMVS versus CMVS in adults.

METHODS

We searched PubMed/MEDLINE, EMBASE, Cochrane Library, LILACS, SciELO, clinical trial registries and grey literature using MeSH terms, without date or language restrictions. Randomised clinical trials (RCTs) comparing MIMVS and CMVS in adults (≥18 years) were included. Robotic, endovascular and redo procedures were excluded. Two reviewers independently extracted data following Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. Risk of bias was assessed with the Cochrane tool, and certainty of evidence with Grading of Recommendations, Assessment, Development and Evaluation. Meta-analyses used random-effects models. Primary outcomes were mortality, acute kidney injury (AKI) and wound infection.

RESULTS

Nine studies (1248 patients) from eight RCTs were included (686 CMVS, 562 MIMVS). MIMVS showed no significant difference in mortality or AKI compared with CMVS. There was a trend towards fewer wound infections (risk ratio=0.47; 95% CI=0.22 to 1.00) and shorter intensive care unit (ICU) stay (mean difference=-0.71 days; 95% CI=-1.47 to 0.04). MIMVS reduced reoperation for bleeding (RR=0.24; 95% CI=0.06 to 0.92) and hospital stay (mean difference=-1.83 days; 95% CI=-3.03 to -0.64). Operative times were longer with MIMVS, but without clinical impact. Stroke, myocardial infarction, mechanical ventilation time and transfusion rates were similar. Most studies had low risk of bias, with moderate to high certainty of evidence. No heterogeneity was detected for primary outcomes.

CONCLUSION

MIMVS enhances postoperative recovery through shorter hospital stays, fewer reoperations for bleeding and a trend towards fewer wound infections and shorter ICU stays compared with CMVS. Despite longer operative times, key safety is comparable between techniques. The overall certainty of evidence is high for most outcomes, supporting strong clinical recommendations in favour of MIMVS.

PROSPERO REGISTRATION NUMBER: CRD42022321939.