Background. Excessive bleeding after cardiac surgical procedures sometimes necessitates reexploration. This study described the associations between reexploration for bleeding and morbidity and mortality after cardiac surgical procedures. In addition, independent predictors of reexploration were identified. Methods. This retrospective observational study based on prospectively registered data included 5,392 consecutive cardiac surgical operations performed from 2009 through 2013. Reexplorations for bleeding within 24 hours of surgical procedures and perioperative morbidity and mortality (30-day, 90-day, and from 90 days until the end of follow-up) were registered. Factors independently associated with mortality, morbidity, and reexploration were identified with multivariable logistic or Cox regression models. Mean follow-up time was 2.4 years (range 0 to 5 years). Results. In this study, 320 patients (6.0%) underwent surgical reexploration. These patients had higher unadjusted mortality at 30 days, 90 days, and more than 90 days (all p < 0.0001). The increased risk remained statistically significant after adjustment for other risk factors at 90 days (odds ratio [OR]: 1.82; 95% confidence interval [CI]: 1.13 to 2.93; p = 0.013) and at more than 90 days (hazard ratio: 1.72; 95% CI: 1.14 to 2.61; p = 0.010). Reexploration was, after adjustment, independently associated with prolonged stay in the intensive care unit (> 24 hours), perioperative stroke, perioperative renal injury, need for dialysis postoperatively, prolonged mechanical ventilation (> 72 hours), and postoperative mechanical circulation support. Independent risk factors for reexploration were low body mass index, high EuroSCORE, low preoperative fibrinogen plasma concentration, long extracorporeal circulation time, combined valve and coronary artery bypass operations, and dual antiplatelet therapy less than 5 days preoperatively. Conclusions. Excessive bleeding leading to reexploration is associated with a twofold increased early postoperative mortality rate. Reexploration for bleeding is also associated with mortality beyond 90 days after operation. (C) 2016 by The Society of Thoracic Surgeons