Phys · cardiovascular
Anticoagulation and Antiplatelet Therapy (Physician-Managed)
Also known as anticoagulation · antiplatelet therapy · warfarin · DOAC · apixaban · rivaroxaban · dabigatran · edoxaban · DAPT · dual antiplatelet therapy · anticoagulant reversal · bridging anticoagulation · HIT
Consultant-physician-depth guide to anticoagulant and antiplatelet prescribing — warfarin and the DOACs with doses and renal thresholds, VTE duration, mechanical valves, reversal agents, perioperative management, HIT, cancer-associated VTE, DAPT and triple therapy — structured for FRACP DWE and DCE preparation.
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Target exams
Red flags
- Mechanical heart valve on a DOAC — contraindicated; warfarin only (RE-ALIGN showed harm with dabigatran)
- Falling platelets 5-10 days into heparin with new thrombosis — HIT until proven otherwise; stop all heparin immediately
- Intracranial or haemodynamically significant bleeding on an anticoagulant — activate reversal pathway now
- DAPT stopped within the first months after coronary stenting — risk of stent thrombosis and death
- Unprovoked VTE in a patient over 50 — consider occult malignancy and take the history and examination seriously
Anticoagulation and Antiplatelet Therapy (Physician-Managed)
Meet the patient
A 74-year-old with atrial fibrillation and three falls in six months sits in your clinic, her apixaban held by a worried locum. Her CHA₂DS₂-VASc is 4; her creatinine clearance sits around 38. The registrar asks whether the falls make anticoagulation too dangerous.[34]
They do not — and proving that with arithmetic is the single skill this whole topic rewards. Antithrombotic prescribing is risk arbitration: every decision trades a thrombotic risk you can quantify against a bleeding risk you can modify, and the examiner wants to hear you do the sums aloud.[33]
References35ShowHide
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- [13]Agnelli G, Becattini C, Meyer G, et al. Apixaban for the Treatment of Venous Thromboembolism Associated with Cancer N Engl J Med, 2020.PMID 32223112
- [14]Raskob GE, van Es N, Verhamme P, et al. Edoxaban for the Treatment of Cancer-Associated Venous Thromboembolism N Engl J Med, 2018.PMID 29231094
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- [20]Douketis JD, Spyropoulos AC, Duncan J, et al. Perioperative Management of Patients With Atrial Fibrillation Receiving a Direct Oral Anticoagulant JAMA Intern Med, 2019.PMID 31380891
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- [22]Wiviott SD, Braunwald E, McCabe CH, et al. Prasugrel versus clopidogrel in patients with acute coronary syndromes N Engl J Med, 2007.PMID 17982182
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- [24]Mauri L, Kereiakes DJ, Yeh RW, et al. Twelve or 30 months of dual antiplatelet therapy after drug-eluting stents N Engl J Med, 2014.PMID 25399658
- [25]Bowman L, Mafham M, Wallendszus K, et al. Effects of Aspirin for Primary Prevention in Persons with Diabetes Mellitus N Engl J Med, 2018.PMID 30146931
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- [27]Gaziano JM, Brotons C, Coppolecchia R, et al. Use of aspirin to reduce risk of initial vascular events in patients at moderate risk of cardiovascular disease (ARRIVE): a randomised, double-blind, placebo-controlled trial Lancet, 2018.PMID 30158069
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- [30]Cannon CP, Bhatt DL, Oldgren J, et al. Dual Antithrombotic Therapy with Dabigatran after PCI in Atrial Fibrillation N Engl J Med, 2017.PMID 28844193
- [31]Lo GK, Juhl D, Warkentin TE, et al. Evaluation of pretest clinical score (4 T's) for the diagnosis of heparin-induced thrombocytopenia in two clinical settings J Thromb Haemost, 2006.PMID 16634744
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