FRIDAY, July 29 (HealthDay News) -- Compared to unfractionated heparin (UFH), low-molecular-weight heparin (LMWH) is associated with reduced mortality and reduced major bleeding in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI); but it shows no benefit in those treated with PCI after thrombolysis, according to a study published online July 20 in the Journal of Thrombosis and Haemostasis.
Eliano Pio Navarese, M.D., from the Nicolaus Copernicus University in Bydgoszcz, Poland, and colleagues reviewed available literature to compare the safety and efficacy of LMWH with UFH in patients with STEMI treated either with pPCI or with PCI after thrombolysis. A total of 10 studies, including 16,286 patients, were analyzed. All-cause mortality and major bleeding complications were the outcome measures after a median follow-up of two months. Relative risk (RR) with 95 percent confidence interval, and absolute risk reduction (ARR) were the effect measures.
The investigators found that enoxaparin was the most frequently used LMWH. In the pPCI group, compared to UFH, LMWHs were associated with a reduction in mortality (RR, 0.51; ARR = 3 percent) and major bleeding (RR, 0.68; ARR = 2 percent). However, the PCI group after thrombolysis showed no benefits with LMWH. Meta-regression revealed greater LMWH benefits in patients with higher baseline risk.
"LMWHs were associated with greater efficacy and safety than UFH in STEMI patients treated with pPCI, with a significant relationship between risk profile and clinical benefits. Based on this meta-analysis, LMWH may be considered as a preferred anticoagulant among STEMI patients undergoing pPCI," the authors write.