Saphenous Vein Graft Thrombosis Secondary to Heparin Induced Thrombocytopenia Two Weeks After Coronary Artery Bypass Graft Surgery
Document Type
Article
Abstract
Background: Heparin induced thrombocytopenia (HIT) with graft thrombosis has been noted in intra operative or early post-operative periods in patients undergoing coronary artery bypass grafting (CABG). There are no reported cases of CABG graft thrombosis occurring outside the perioperative period. We report a patient who developed saphenous vein graft (SVG) thrombosis secondary to heparin exposure 2 weeks after CABG.
Case: A 66 year old male with coronary artery disease underwent CABG with left internal mammary artery graft to the left anterior descending artery and SVGs to diagonal 1, obtuse marginal 1, right posterior descending, and right posterolateral branch arteries. 2 weeks after discharge the patient returned with pleuritic chest pain secondary to an acute pulmonary embolism. Intravenous (IV) heparin was initiated. On day 2 the patient had recurring chest pain. Troponin I was 6.6 ng/mL, peaking at 20 ng/mL in 4 hours. Platelet count was 82,000/uL, decreased from 250,000/uL on presentation. Left heart catheterization (LHC) showed 100% stenosis in the proximal 3rd of the SVG to the diagonal 1 branch, 95% stenosis of the SVG to obtuse marginal 1, and 100% occlusion of the proximal 3rd of SVG to right coronary artery.
Decision-making: Given the large thrombus burden, thrombocytopenia, with ongoing heparin infusion, HIT was suspected. Further coronary interventions were held. Heparin was transitioned to IV argatroban, and after 3 days, repeat LHC showed a patent SVG to the diagonal 1 with TIMI 2 flow in the distal vessel, a less prominent thrombus in the graft to the obtuse marginal 1, and a widely patent right coronary artery bypass graft. Subsequent heparin induced platelet antibody and serotonin release assays were highly positive. He was discharged on apixaban and dual antiplatelets. 1 month later, LHC showed that all SVG thrombi had abated.
Conclusion: While seroprevalence of heparin-dependent antibodies among cardiac surgery patients is striking, development of HIT with thrombosis is uncommon. Diagnosis of HIT is often challenging given the natural inclination of post-operative patients to develop thrombocytopenia. A high index of suspicion is needed for timely recognition and management.
First Page
3805
DOI
10.1016/S0735-1097(23)04249-3
Publication Date
3-7-2023
Recommended Citation
Amaratunga EA, Antoine MK, Thacker P, Shirani J. SAPHENOUS VEIN GRAFT THROMBOSIS SECONDARY TO HEPARIN INDUCED THROMBOCYTOPENIA TWO WEEKS AFTER CORONARY ARTERY BYPASS GRAFT SURGERY. Journal of the American College of Cardiology. 2023 Mar 7;81(8_Supplement):3805-.