Certoparin versus unfractionated heparin to prevent venous thromboembolic events in patients hospitalized because of heart failure: A subgroup analysis of the randomized, controlled CERTIFY study

Background Despite the elevated risk for developing venous thromboembolic events in patients with heart failure, there are no randomized, double-blind, controlled trial data on the comparison of low-molecular-weight heparin with unfractionated heparin (UFH) in this patient population. Methods This was a subgroup analysis of the CERTIFY trial, which included 3,239 nonsurgical, acutely ill medical patients 70 years or older. Patients were randomized to receive 3,000-U anti-Xa certoparin once daily or 5,000-IU UFH 3 times a day. The analysis was performed on a subgroup of 542 patients diagnosed with heart failure at hospital admission. Results Patients with heart failure differed from patients without heart failure in that they were more likely using antiplatelets (67.2% vs 48.9%; P < .0001) and had a lower glomerular filtration rate (8.0% vs 5.5%; ≤30 mL/min per 1.73 m2 ; P = .0232). Thromboembolic risk was comparable except for a higher incidence of distal deep venous thrombosis (DVT) in patients with heart failure (10.80% vs 7.26%; P = .0144). Within the heart failure population, patient characteristics were comparable between randomized treatment groups. The incidence of the primary end point (proximal DVT, symptomatic nonfatal pulmonary embolism, and venous thromboembolism–related death combined) was numerically, slightly smaller with certoparin (3.78% vs 4.74% with UFH; odds ratio 0.79, 95% CI 0.32-1.94), and the incidence of major bleeding was 0.72% with certoparin versus 0.38% with UFH. Conclusions Patients hospitalized for heart failure are at high risk for developing distal DVT and bleeding complications compared with acutely ill medical patients without heart failure. Within the heart failure population, the observed differences in prophylactic efficacy between 3,000-U anti-Xa certoparin once daily and 5,000-IU UFH 3 times a day were similar to those observed in the overall study population; this suggests that certoparin might be at least as effective as UFH also in this subgroup. There were no relevant differences in bleeding risk or frequency of adverse events.