[Critical analysis of early heparin therapy in cerebral ischemic infarction].

This is a critical review of the role of heparin in the acute phase of ischemic cerebral vascular accident (CVA). Completed clinical trials lead to the following conclusions: 1. The efficacy of heparin in the acute phase of CVA is unknown, given the many biases and methodological imprecisions contained in the studies performed so far, among them a reliance on temporal rather than etiological classification of infarctions and the small number of patients treated. 2. Heparin-related complications have been explored only anecdotally and retrospectively, even though the risk of hemorrhage would depend on the magnitude of the prolongation of PTTa. The severity of neurological deficit, infarction size and patient age, on the other hand, would be contributing factors. 3. Delay in start of heparin therapy based on the severity of clinical symptoms is not supported by the evidence. There are prospective studies, on the other hand, that indicate a lack of correlation between early instauration of heparin therapy and the appearance of complications in severe stroke. 4. PTTa must be controlled carefully in the heparinized patient and administration of the drug in continuous perfusion or by subcutaneous injection is recommended.