Abstract
Increasingly hemophiliacs are reaching ages where they acquire coronary artery disease (CAD) that necessitates consideration of coronary artery bypass grafting surgery (CABG). Treatment of vasculopathic hemophiliacs can be challenging in that there are no specific guidelines for this setting, particularly with respect to anticoagulant use. Detailed here are two cases of mild hemophilia who presented in 2003 with symptomatic, unstable CAD and who elected CABG. The first was a 48 year old man with CAD, unstable angina, hypertension, diabetes mellitus, hyperlipidemia, polycystic kidney disease, cigarette use, obstructive sleep apnea, obesity, and mild hemophilia-B that had manifested in his third decade as post-surgical hemorrhages. His factor IX activity had been measured at 20% and the inhibitor screening was negative. His body mass index was high (34). Cardiac catheterization demonstrated moderate to severe three-vessel stenoses with regional myocardial hypokinesis. Pre-CABG he was infused with a non-recombinant human factor IX dose [calculated at 80% of total body replacement (6,700 units)] per manufacturers infusion protocol. Within ten minutes of infusion the patient developed substernal chest pain radiating to the left arm, dyspnea, ischemic pattern on electocardiogram (EKG), bradycardia, hypotension, and unresponsiveness. Resuscitation attempts were immediately instituted but the patient expired. The second case was that of a 57 year old man with CAD, unstable angina, cigarette use, hyperlipidemia, obesity, rheumatoid arthritis, and mild hemophilia-A that had manifested in the past as easy bruisability and dental bleeding. His factor VIII activity was measured at 9% and the inhibitor screening was negative. Coronary catheterization revealed moderate to severe three-vessel stenoses. Pre-CABG the patient was infused simultaneously with recombinant human factor VIII {Caculated at 80% of total body replacement (5,000 units)] and unfractionated heparin (to keep partial thromboplastin time at 2.5 times the normal range) before being placed on the pump-oxygenator at surgery. A pentuple CABG (including an internal mammary artery graft) was performed without incident. Post-operatively factor VIII and unfractionated heparin infusion protocols were restarted. The heparin was discontinued prophylactically by the surgical team to prevent wound bleeding at three hours post-surgery. Within 90 minutes of heparin stoppage, the patient developed chest pain, ventricular arrhythmia, and EKG-troponin-creatine phosphokinase changes consistent with a sub-endocardial myocardial infarction. Heparin was immediately restarted and the remainder of the hospitalization was uneventful. In the two cases cited, mild hemophiliacs with unstable CAD suffered coronary thromboses when antihemophiliac factor therapy was unopposed by simultaneous anticoagulant therapy. We can find no previous approaches to this important scenario in the literature. Our experience here suggests that systematic, prospective study of anticoagulant protocol in vasculopathic hemophiliacs undergoing CABG is needed.
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