The following patients should have antiplatelet therapy for life (unless they develop an indication for anticoagulation):
Aspirin oral 75mg daily (dispersible tablet) is the agent of choice (but see separate guidance here for stroke and TIA). Enteric coated aspirin does not reduce gastrointestinal (GI) symtoms. Only if aspirin is contraindicated or the side effects are intolerable (see section below 'Contraindications to aspirin') should clopidogrel oral 75mg daily be used instead.
Caution with all antiplatelets - ideally blood pressure should be under control (<150/90mmHg) prior to commencing any antiplatelet agent, and certainly systolic <180mmHg.
|Indication||Drug regimens and duration|
|Thrombotic stroke (also see additional 'Notes' below)|
|Stable thrombotic stroke or TIA||See Secondary Prevention of Stroke and TIA guideline|
|Carotid artery stent||Aspirin oral 75mg daily indefinitely AND clopidogrel oral 75mg daily for 4 weeks|
|ST elevation MI|
|Primary PCI drug-eluting stent||Aspirin oral 75mg indefinitely AND ticagrelor oral 90mg twice daily for 6 months|
|Primary PCI bare metal stent||Aspirin oral 75mg indefinitely AND ticagrelor oral 90mg twice daily for 3 months|
|Angiography only / Medical management||Aspirin oral 75mg indefinitely AND ticagrelor oral 90mg twice daily for 3 months|
|Non-ST elevation MI|
|PCI with drug-eluting stent||Aspirin oral 75mg indefinitely AND ticagrelor oral 90mg twice daily for 6 months|
|PCI with bare metal stent||Aspirin oral 75mg indefinitely AND ticagrelor oral 90mg twice daily for 3 months|
|Medical management||Aspirin oral 75mg indefinitely AND ticagrelor oral 90mg twice daily for 3 months|
|Elective PCI in stable coronary artery disease|
|Drug-eluting stent||Aspirin oral 75mg daily indefinitely AND clopidogrel oral 75mg daily for 6 months|
|Bare metal stent||Aspirin oral 75mg indefinitely AND clopidogrel oral 75mg daily for 4 weeks. Some patients may receive clopidogrel 150mg daily for the first week and/or a 3 month course of clopidogrel at the discretion of the interventional cardiologist.|
This combination is associated with a significantly higher major haemorrhage complication rate than either agent alone, without offering any proven benefit in reducing ischaemic or thromboembolic events (except in patients with metallic prosthetic heart valves).
Low thrombosis risk patients (e.g. moderate risk atrial fibrillation (AF), deep vein thrombosis (DVT) >3 months previously) who develop an indication for dual antiplatelet therapy (e.g. AF patient requiring coronary stent) should stop warfarin or receive triple therapy for as short a time as possible. Consideration should be given to the use of a bare metal stent.
High thrombosis risk patients (e.g. high risk AF, recent venous thromboembolism) developing an ACS, require specialist advice and be considered for triple therapy.
In patients with stable vascular disease, on a single antiplatelet agent, this agent should be discontinued for the duration of warfarin therapy.
In patients with unstable vascular disease (e.g. recent ACS or stent) receiving dual antiplatelet therapy warfarin should be commenced cautiously with close monitoring and discontinuation of aspirin +/- ticagrelor / clopidogrel earlier than planned should be discussed with an interventional cardiologist.
It is accepted that some high thrombotic risk patients, with low inherent bleeding risk, may merit short-term triple therapy, however each case should be considered individually with a full risk:benefit assessment.
These are rare, but include aspirin allergy (aspirin-induced angioedema, asthma or skin rash).
Relative contraindications for all antiplatelet agents (only prescribe on expert advice):
|Consider other contributory factors e.g.:
If GI symptoms persist despite modification of contributory factors:
Patient complying and GI symptoms still persist?
(This will be a rare event.)
Change to clopidogrel oral 75mg daily (secondary prevention only) and stop PPI.
Seek specialist gastroenterology advice if symptoms do not resolve.