Patients with first-time acute deep vein thrombosis (DVT) or pulmonary embolism (PE) were administered unfractionated heparin (UFH) more frequently than low molecular weight heparin (LMWH), despite the fact that existing guidelines endorse LMWH rather than UFH in this setting. These results of a single-center study were presented at the Thrombosis & Hemostasis Summit of North America (THSNA) 2020 Virtual Conference.
The findings were presented by Saranya Dinesan, MD, of the Charleston Area Medical Center and West Virginia University — Charleston Division, in Charleston, West Virginia, and colleagues.
“We had several physicians who complained of overuse of heparin in the hospital setting with acute DVT/PE patients, especially with those patients requiring longer times to attain therapeutic aPTT,” said Dr Dinesan.
Along with advantages in dosing and monitoring requirements, the authors noted that LMWH is more cost-effective than UFH and has been shown to reduce heparin-induced thrombocytopenia when UFH is replaced with LMWH.
The retrospective cohort study used data from hospitalized patients with acute DVT/PE at the Charleston Area Medical Center from July to December 2018. Patients with creatinine clearance of less than 30 cc/min, acute coronary syndrome, prior diagnosis of HIT, extremes of weight (BMI >40 kg/m2 and weight <50 kg), or thrombocytopenia were excluded from the study.
In total, 228 patients (mean age, 64 years; 54% men) with DVT (48%) or PE (52%) were included in the study. Common comorbidities included diabetes (26%), hypertension (53%), and cancer (21%).
Overall, 75.4% and 24.6% of patients received UFH and LMWH, respectively. No differences among studied patient characteristics had an effect on treatment choice, including age (UFH vs LMWH, respectively: mean age, 62 ± 16 years vs 59 ± 18 years; P =.15), sex (% female, 45% vs 52%; P =.36), BMI (30 vs 28; P =.06) or presence of hypertension (55% vs 46%; P =.25), diabetes (28% vs 20%; P =.22), or cancer (21% vs 32%; P =.70). The length of hospital stay did not vary significantly between the 2 groups (8.5 ± 7 days for UFH vs 8.0 ± 9 days for LMWH; P =.70).
Among all patients, the median time to a therapeutic level for activated partial prothromboplastin time was 7 hours, but there was considerable variability from 17.20% of patients who needed 6 hours or less to 4% who needed more than 36 hours.
Adverse events during hospital stay included 4 cases of nontraumatic intracerebral hemorrhages (all UFH patients). However, no instances of heparin-induced thrombocytopenia occurred.
Major limitations of this study included its retrospective, single-center design, small sample size, and a lack of long-term follow up data.
“Several studies have shown that direct oral anticoagulant drugs (DOACs), such as rivaroxaban and apixaban, can be used as initial therapy for acute DVT/PE. These agents may eventually supplant the use of parenteral anticoagulants such as UFH and LMWH as drugs of choice for patients with DVT/PE,” wrote the authors.
In future studies, the team plans to evaluate whether choice of anticoagulation had an effect on morbidity, mortality, and recurrence of DVT/PE.
Dinesan S, Jubelirer SJ, Welch CA, et al. The overuse of unfractionated heparin (UFH) versus low molecular weight heparin (LMWH) in hospitalized patient with acute deep vein thrombosis (DVT) and pulmonary embolism (PE). Abstract presented at: THSNA 2020 Thrombosis & Hemostasis Summit of North America; October 27-30, 2020. Abstract 134.