title: An unusual presentation of heparin-induced thrombocytopenia in the setting of catheter-directed ablation of atrial fibrillation.
abstract: Heparin-induced thrombocytopenia type 2 is an immune-mediated phenomenon associated with heparin exposure that has the potential to evolve into life-threatening thrombosis if not recognized and treated early. Lack of immediate availability of a confirmatory assay often leaves the diagnosis to the clinician's discretion. Despite a high negative predictive value, the clinical '4Ts' scoring system carries a small but a real risk of missing the diagnosis, especially with atypical presentations. We describe one such case of rapid-onset, heparin-induced thrombocytopenia with thrombosis that developed in the setting of catheter-directed ablation of atrial fibrillation, several months after a brief exposure to low-molecular-weight heparin. The clinical scenario as well as the risk of progressing to catastrophic complications prompted immediate discontinuation of all heparin products and treatment with a direct thrombin inhibitor, despite a low pretest clinical score.
authors.affiliation: Department of Internal Medicine, Division of Hematology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Rakhee
authors.initials: R
authors.lastname: Vaidya
authors.forename: Rajiv
authors.initials: R
authors.lastname: Pruthi
authors.forename: Carrie
authors.initials: C
authors.lastname: Thompson
mesh_terms: D000925:Anticoagulants / Q000009:adverse effects* / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000150:complications* / Q000601:surgery; D006495:Heparin, Low-Molecular-Weight / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D013921:Thrombocytopenia / Q000139:chemically induced* / Q000150:complications / Q000175:diagnosis*
chemical_list: D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight