Low-molecular-weight heparins in the treatment of pulmonary embolism

More than 621 patients diagnosed with a PE have been treated with LMWH. This review included five randomized clinical trials (> 433 patients treated with LMWH) comparing LMWH with UFH. The remainder of the clinical studies were dose-response trials, noncomparative trials, or trials that included a subset of patients diagnosed with a PE. Additionally, 138 patients diagnosed with a PE were included in the group of 510 patients with venous thromboembolism and were subsequently treated with an LMWH. The data available suggest that LMWHs may be safe and effective in the treatment of submassive PE. However, the current data on LMWHs are limited by small sample size, inadequate patient description, and inadequate follow-up. The majority of studies fail to provide concurrent disease state information (e.g., renal disease), thus limiting their usefulness. The results of these trials must be confirmed in comparative studies using different LMWHs (since they may not be interchangeable) in various patient populations before LMWHs are considered to be a safe and effective alternative to UFH in the management of submassive PE.