Scar-specific outcomes following minimally invasive versus conventional median sternotomy in cardiac surgery: A systematic review and meta-analysis

Background With improved cardiac surgical outcomes, attention has shifted to patient-centred outcomes, including cosmetic appearances of surgical scars. Minimally invasive cardiac surgery (MICS) is often promoted for its cosmetic benefits, yet empirical evidence remains limited. This study aimed to systematically evaluate scar-specific outcomes comparing MICS to conventional full median sternotomy (FMS) in adult cardiac surgery. Methods A systematic review and meta-analysis was conducted following PRISMA guidelines. PubMed, Embase, Central, and Scopus were searched from inception to August 2025. Studies comparing MICS to FMS, reporting scar-related patient-reported outcomes, wound complications, or cosmetic satisfaction, were included. The primary outcome was scar assessment using validated instruments. Random-effects models calculated standardised mean differences (SMD) and risk ratios (RR) with 95% confidence intervals. Results Twenty-two studies comprising 3131 patients (1459 MICS, 1672 FMS) met inclusion criteria. MICS demonstrated significantly better scar assessment scores (SMD −0.74, 95% CI −1.27 to −0.22; p < 0.01; I 2 = 88%, six studies), higher patient satisfaction rates (RR 1.42, 95% CI 1.21–1.66; p < 0.001; I 2 = 84%, 12 studies), and reduced wound complications (RR 0.31, 95% CI 0.20–0.47; p < 0.001; I 2 = 0%, nine studies). Only six studies reported validated scar assessment scores, highlighting limited integration of these measures. Substantial heterogeneity was observed due to diverse assessment tools and surgical techniques. Conclusions MICS can offer significant advantages in scar-specific outcomes compared to FMS in carefully selected patient populations. Cosmetic outcomes should be interpreted within the context of overall effectiveness and may support shared decision making only when clinical outcomes between surgical approaches are comparable. The lack of standardised scar assessment protocols and limited reporting of cosmetic outcomes represent critical gaps. Future research should prioritise standardised scar evaluation tools and expand cosmetic outcome reporting across all cardiac surgical procedures.