In their recent article, Hull et al1 state that "inadequate initial heparin therapy predisposes patients to late recurrence of thromboembolism [TE]." They defined "inadequate heparin therapy" as the failure of the activated partial thromboplastin time (aPTT) to reach a preselected value within 24 hours of the initiation of heparin therapy, without providing any evidence that patients whose aPTT did not reach this level received inadequate treatment. In fact, several points argue against this assumption.
Shojania AM. The Importance of Initial Heparin Treatment on Long-term Clinical Outcomes. Arch Intern Med. 1998;158(11):1270-1272. doi: