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A3411 - Catastrophic Antiphospholipid Syndrome and Heparin Induced Thrombocytopenia After Pulmonary Vein Isolation Ablation
Author Block: L. Khalid1, T. B. Ferreira2, O. Sheikh3, J. J. Byrnes4; 1Pulmonary and Critical Care Medicine, Jackson Memorial Hospital/ University of Miami, Miami, FL, United States, 2Pulmonary and Critical Care Medicine, University of Miami, Miami, FL, United States, 3Jackson memorial hospital, Miami, FL, United States, 4Hemetology and Oncology, University of Miami, Miami, FL, United States.
Introduction: Antiphospholipid syndrome can rarely manifest as catastrophic antiphospholipid syndrome (CAPS). Main characteristics of the syndrome are small vessel thrombosis, microangiopathic hemolytic anemia and rapid onset multisystem involvement. The underlying mechanism is believed to be proinflammatory and prothrombotic milieu created by antiphospholipid antibodies directed against a heterogeneous group of phospholipid associated proteins. Heparin induced thrombocytopenia (HIT) is similar to antiphospholipid syndrome in that both are mediated by prothrombotic autoantibodies. Case: We present a case of a 53 year old male with known antiphospholipid syndrome, hypertension and atrial fibrillation who developed catastrophic antiphospholipid syndrome after pulmonary vein isolation ablation. Patient presented with acute renal failure, bilateral adrenal hemorrhage and multiple deep venous thrombosis. He was started on anticoagulation with heparin and developed heparin induced throbocytopenia with positive platelet factor 4 and serotonin assay. He was then transitioned to Argatroban. His clinical course was further complicated by diffuse alveolar hemorrhage after steroids were tapered and thrombotic cerebrovascular accidents. Patient was treated with high dose steroids and once clinically stable restarted on anticoagulation with argatroban and bridged to coumadin with good clinical response. Discussion: Pulmonary vein isolation ablation is increasingly being used to treat atrial fibrillation. This procedure involves isolation of pulmonary veins and burning tissue around the veins to create scar tissue. The endothelial injury releases phospholipids which can lead to autoantibody mediated disseminated acute thrombotic microangiopathy leading to multi organ failure as seen in our patient. This case not only helps highlight that minimally invasive procedures that cause endothelial injury can lead to a significant “second hit” in patients with antiphospholipid syndrome leading to catastrophic events but also documents simultaneous occurrence of CAPS and clinical heparin induced thrombocytopenia (HIT). Although around 65% of patients with CAPS will have thrombocytopenia it is important to have high suspicion for HIT not only as a differential for the multiple thrombi but also as a coexisting entity. Catastrophic antiphospholipid syndrome creates a systemic inflammatory response which leads to platelet activation and can predispose these patients to heparin induced thrombocytopenia.