Impact of Deep Sternal Wound Infection on Long-Term Survival Based on Revascularisation Strategy: Results From the Polish National Registry.

Background: This multicentre study aimed to investigate the impact of deep sternal wound infection (DSWI) on long-term survival among patients undergoing coronary artery bypass grafting (CABG) using multiple arterial grafting (MAG) or single artery with saphenous vein grafts (SAG).

Methods: Data were obtained from the Polish National Registry of Cardiac Surgery Procedures database. Between January 2012 and December 2020, 81,136 patients who underwent CABG for multivessel disease were included in the study. Patients were divided into four groups: MAG with DSWI (n=219), MAG without DSWI (n=8,611), SAG with DSWI (n=1,432), and SAG without DSWI (n=70,874). Inverse probability of treatment weighting based on the generalised propensity score was used to minimise imbalance between the groups.

Results: In the weighted sample, DSWI in patients who received MAG was associated with reduced long-term survival when compared with patients without DSWI and MAG (hazard ratio [HR] 1.89, 95% confidence interval [CI] 1.29-2.78; Bonferroni corrected p=0.01). Deep sternal wound infection in patients who received SAG was associated with reduced long-term survival when compared with patients without DSWI and SAG (HR 1.92, 95% CI 1.69-2.17; Bonferroni corrected p=0.01). In patients who did not develop DSWI, MAG was associated with improved long-term survival compared with SAG (HR 0.68, 95% CI 0.63-0.74; Bonferroni corrected p=0.01). However, patients who received MAG and developed DSWI had similar long-term survival when compared with patients who received SAG and did not develop DSWI (HR 1.31, 95% CI 0.90-1.92; Bonferroni corrected p=0.63). A landmark analysis excluding the first 6 months of follow-up was performed to exclude the risk of acute mortality due to DSWI. In the weighted sample, the results were consistent with the main analysis.

Conclusion: Deep sternal wound infection is associated with worse survival in patients receiving MAG and SAG. Moreover, the superior effect of MAG over SAG diminishes once DSWI develops.