Underrecognized cardiovascular complications after hepatectomy: population-level mortality burden from a multicentre population-attributable fraction (PAF) analysis.

Postoperative complications remain major determinants of outcomes after hepatectomy for hepatocellular carcinoma (HCC), but whether complications that prolong hospitalization are also those that contribute most to mortality remains unclear. This multicentre cohort study included 1,883 patients undergoing curative-intent hepatectomy for HCC across seven tertiary centers. Postoperative complications were categorized by organ system, and adjusted population-attributable fractions (PAFs) were calculated to estimate their contributions to 90-day mortality and prolonged hospital stay. Multivariable Cox models were used to assess associations with overall survival and recurrence-free survival. A divergence between hospitalization burden and mortality burden was observed. Liver surgery-specific complications accounted for the largest population-level burden of prolonged hospitalization (PAF 11.0%) and 90-day mortality (PAF 10.0%). Cardiovascular complications were the leading non-liver contributor to 90-day mortality (PAF 9.4%), despite a smaller contribution to prolonged hospitalization (PAF 4.1%). Pulmonary complications, cardiovascular complications, renal complications, and glucose dysregulation were independently associated with worse overall survival, whereas no complication domain was independently associated with recurrence-free survival. These findings show that postoperative recovery burden and mortality burden are not interchangeable after hepatectomy. Liver surgery-specific complications dominated hospitalization burden, whereas cardiovascular complications represented an underrecognized non-liver contributor to early mortality and worse long-term survival. An integrated perioperative framework incorporating systematic cardiovascular risk assessment may improve risk prioritization after hepatectomy for HCC.