Post-Myocardial Infarction

Clinical Snapshot

The post-myocardial infarction (post-MI) period begins once the acute presentation described in Acute Coronary Syndromes — STEMI or NSTEMI — has been stabilized, reperfused where appropriate, and the patient is being prepared for or has completed hospital discharge. The clinical task shifts from minutes-matter reperfusion to lifelong secondary prevention: several independent drug classes, layered together, each reduce the risk of a subsequent major adverse cardiovascular event (MACE) — reinfarction, stroke, or cardiovascular death — with additive rather than overlapping benefit, so a patient undertreated on any one pillar is measurably worse off.^[1] This chapter covers the pharmacotherapy, duration decisions, and monitoring that carry a post-MI patient from the day of discharge through the rest of their life, and assumes the acute-phase diagnosis and initial reperfusion/antithrombotic therapy in Acute Coronary Syndromes has already occurred.

Recognize the Condition

A patient enters this chapter's scope the moment their index STEMI or NSTEMI has been diagnosed and acute management started — there is no separate diagnostic step for "post-MI" itself. What changes is the clinical task: instead of confirming the diagnosis, the pharmacist and prescriber are now tracking recovery, watching for early complications, and building the long-term drug regimen. Residual angina, new or worsening dyspnea, palpitations, and mood/sleep disturbance are all common in the weeks after MI, and each points toward a different problem — recurrent ischemia, evolving heart failure, arrhythmia, and depression, respectively — so a nonspecific "not feeling right" complaint after MI always deserves a specific follow-up question, not reassurance alone.

The clinical phenotypes that drive secondary-prevention drug selection

Reduced LV systolic function (LVEF ≤ 40%)

Drives indefinite ACE inhibitor/ARB and beta-blocker use, mineralocorticoid receptor antagonist eligibility, and eventual ICD referral if the reduction persists.

Preserved LV function (LVEF ≥ 50%), no other indication

The group in whom indefinite beta-blocker therapy is now being reassessed after 1 year rather than continued by default.

Concomitant atrial fibrillation or LV thrombus

Requires layering oral anticoagulation onto — and eventually in place of — antiplatelet therapy, via a specific dual-pathway or short triple-therapy strategy.

High bleeding risk

Shortens planned DAPT duration and shifts P2Y12/anticoagulant choices toward the lowest-bleeding-risk combination available.

High recurrent-ischemic risk

Supports extending DAPT, or adding a second antithrombotic agent, beyond the standard 12-month course — provided bleeding risk is not also high.

Risk Factors

Continued smoking after MI — the single highest-yield modifiable risk factor for recurrent events.
Persistently elevated LDL-C, or nonadherence to prescribed lipid-lowering therapy.
Uncontrolled hypertension.
Diabetes mellitus, particularly with poor glycemic control.
Obesity and sedentary lifestyle.
Chronic kidney disease.
Residual or progressive LV systolic dysfunction.
Incomplete revascularization or extensive multivessel coronary disease.
Depression, anxiety, and low social support — each independently associated with worse cardiovascular outcomes, not just quality of life.
Early or unintentional discontinuation of dual antiplatelet therapy.
Non-attendance at cardiac rehabilitation.

Red Flags & Refer

Any of the following after MI needs urgent assessment rather than routine follow-up:

Recurrent chest pain or pressure suggesting reinfarction or stent thrombosis — this risk is highest in the first weeks to months after PCI and rises sharply if dual antiplatelet therapy has been stopped early or interrupted.
New or worsening dyspnea, orthopnea, paroxysmal nocturnal dyspnea, peripheral edema, or rapid weight gain suggesting heart failure decompensation.
Signs of major bleeding while on dual antiplatelet therapy or an oral anticoagulant — melena, hematemesis, gross hematuria, an unexplained drop in hemoglobin, or any symptom suggesting intracranial hemorrhage (sudden severe headache, focal neurologic deficit, altered consciousness).
New palpitations, presyncope, or syncope suggesting a significant arrhythmia.
Focal neurologic symptoms suggesting stroke or TIA.
Severe, treatment-resistant hypertension, or symptomatic hypotension limiting titration of secondary-prevention drug therapy.
Expressed suicidal ideation or severe depressive symptoms.
A pharmacy-identified gap in P2Y12 inhibitor refills, or any other sign the patient has stopped a secondary-prevention drug without medical guidance — this needs prompt outreach, not just a chart note.

Assessment & Diagnosis

Follow-up history and examination

At the first post-discharge visit (typically within 1-2 weeks), reconcile every discharge medication against what the patient is actually taking, and specifically confirm the P2Y12 inhibitor, its dose, and its planned stop date — early or unintentional DAPT discontinuation is one of the highest-yield things a community pharmacist can catch.
Ask specifically about recurrent chest discomfort, exertional dyspnea, orthopnea, edema, palpitations, and any bleeding symptoms at every visit.
Screen for depression and anxiety at baseline and periodically thereafter — both are common after MI and both independently worsen adherence and cardiovascular outcomes.
Confirm cardiac rehabilitation referral was actually made, and ask whether the patient has started attending.
Blood pressure, resting heart rate, weight, and waist circumference at each visit.

Investigations

Fasting lipid panel 4-6 weeks after starting or changing lipid-lowering therapy, then at least annually once at target.
Serum creatinine and potassium within 1-2 weeks of starting or up-titrating an ACE inhibitor, ARB, or mineralocorticoid receptor antagonist, then periodically once stable.
Reassessment of left ventricular ejection fraction — at least 1 month post-MI in patients managed without revascularization, and at least 3 months post-MI in revascularized patients — to confirm LV recovery, guide continued mineralocorticoid receptor antagonist use, and determine whether a persistently reduced EF warrants implantable cardioverter-defibrillator referral.^[1]
HbA1c in patients with diabetes, per the usual monitoring interval (see Diabetes Mellitus).

Risk stratification for extended dual antiplatelet therapy

The DAPT score is a published point-sum that estimates the ischemic-versus-bleeding tradeoff of continuing a P2Y12 inhibitor beyond 12 months; a score of 2 or higher favours benefit from continuation, while a score below 2 favours stopping.^[2]

Criterion	Points
Age ≥ 75 years	-2
Age 65 to < 75 years	-1
Age < 65 years	0
Current cigarette smoker	+1
Diabetes mellitus	+1
MI at presentation	+1
Prior PCI or prior MI	+1
Stent diameter < 3 mm	+1
Paclitaxel-eluting stent	+1
Congestive heart failure or LVEF < 30%	+2
Saphenous vein graft PCI	+2

The PRECISE-DAPT score is a separate, continuously-weighted tool — age, creatinine clearance, hemoglobin, white cell count, and prior spontaneous bleeding are all entered as continuous or graded values rather than a simple point-sum — that estimates out-of-hospital bleeding risk on DAPT. Because it is a regression-based score rather than an unambiguous point-sum, use a validated external calculator rather than manual scoring.

Treatment Targets

LDL-C below 1.8 mmol/L (70 mg/dL) — or at least a 50% reduction from untreated baseline if that absolute target cannot be reached — on maximally tolerated lipid-lowering therapy.
Blood pressure controlled to the target appropriate for the patient's comorbidities (see Hypertension).
HbA1c below 7% in most patients with diabetes (see Diabetes Mellitus); avoid thiazolidinediones given their heart failure risk.
Resting heart rate 50-60 bpm in patients on beta-blocker therapy.
Complete smoking cessation.
BMI 18.5-25 kg/m2 and waist circumference below 100 cm (men) or 90 cm (women), pursued through a sustained 5-10% weight reduction where indicated.
Completion of a structured cardiac rehabilitation program.
Full adherence to the prescribed dual antiplatelet therapy course for its entire planned duration.
Annual influenza vaccination.
Recognition and treatment of post-MI depression or anxiety where present.

Choose Initial Treatment

DAPT duration tracks after MI

Standard risk

ASA plus a P2Y12 inhibitor for 12 months, then ASA monotherapy indefinitely.

High bleeding risk

Short DAPT — ASA plus a P2Y12 inhibitor for 1-3 months, then P2Y12 inhibitor (or ASA) monotherapy indefinitely.

High ischemic risk, low bleeding risk

Consider extending DAPT beyond 12 months, or an extended low-dose antithrombotic combination, for up to 3 years.

Concomitant atrial fibrillation or LV thrombus

Oral anticoagulation is layered onto — and eventually replaces — antiplatelet therapy; see the anticoagulation decision below.

Direct treatment rule

Antiplatelet therapy

1st line ASA 81 mg PO daily, started at diagnosis and continued indefinitely in essentially every post-MI patient regardless of any later P2Y12-inhibitor decision.

1st line P2Y12 inhibitor ticagrelor or prasugrel, added to ASA as dual antiplatelet therapy.

Use clopidogrel instead — when ticagrelor/prasugrel are contraindicated, not tolerated (e.g., ticagrelor-associated dyspnea), or when the patient also needs an oral anticoagulant.

Default DAPT duration is 12 months. High bleeding risk (prior major bleed, oral-anticoagulant requirement, advanced CKD, anemia, thrombocytopenia) shortens this to 1-3 months, followed by single antiplatelet monotherapy.^[3]

High ischemic risk, low bleeding risk (recurrent MI, diabetes with prior stent thrombosis, extensive multivessel disease, CKD) supports extending DAPT beyond 12 months, up to 3 years — either ticagrelor 60 mg PO BID plus ASA, or a switch to rivaroxaban 2.5 mg PO BID plus ASA.^[4]

Beta-blocker duration

1st line start a beta-blocker (metoprolol, bisoprolol, or carvedilol) within the first few days post-MI in every patient without a contraindication, titrated to a resting heart rate of 50-60 bpm.

Continue indefinitely — when LVEF remains <50%, or the patient has ongoing angina, a primary arrhythmia indication, hypertension needing the agent, or a history of spontaneous coronary artery dissection.^[1]

Reassess ongoing need at 1 year — in a patient with LVEF ≥50% and no other indication for the drug; a large randomized trial found no reduction in death or reinfarction from routine indefinite beta-blocker use in this specific group.^[5]

If de-escalating, taper gradually in consultation with the prescriber rather than stopping abruptly or unilaterally — a separate randomized trial found that interrupting an already-established beta-blocker was not proven as safe as continuing it, with more cardiovascular hospitalizations in the interruption arm.^[6]

ACE inhibitor or ARB

1st line start an ACE inhibitor (ramipril, perindopril, or lisinopril) within 24-48 hours of MI in every patient without hypotension, and continue indefinitely — benefit is greatest, but not limited to, patients with LVEF <40%, hypertension, diabetes, or chronic kidney disease.

Switch to an ARB — when ACE-inhibitor cough develops. Do not combine an ACE inhibitor with an ARB; combination increases adverse events without added benefit.

Statin and lipid-lowering escalation

1st line, all patients high-intensity statin (atorvastatin 40-80 mg or rosuvastatin 20-40 mg) started before discharge, regardless of baseline LDL-C.

Add if LDL-C ≥1.8 mmol/L (70 mg/dL) on maximally tolerated statin — ezetimibe 10 mg PO daily.^[7]

Add if still ≥1.8 mmol/L (70 mg/dL) despite statin plus ezetimibe — a PCSK9 inhibitor (evolocumab or alirocumab) or inclisiran.

Consider bempedoic acid as an additional or alternative non-statin option for patients who remain above target, or who are statin-intolerant.

Mineralocorticoid receptor antagonist

Special situation add eplerenone or spironolactone when LVEF is ≤40% and the patient has either clinical heart failure or diabetes, provided the patient is already on an ACE inhibitor/ARB and a beta-blocker, has a serum potassium ≤5.0 mmol/L, and an eGFR ≥30 mL/min/1.73m2.^[8]

Anti-inflammatory therapy

Consider low-dose colchicine 0.5 mg PO daily for residual inflammatory risk in a patient with established coronary disease who remains on optimized standard secondary prevention, provided eGFR is at least 30 mL/min/1.73m2 and there is no significant hepatic/biliary disease or severe heart failure.^[9]

Anticoagulation for atrial fibrillation or LV thrombus

LV thrombus warfarin (target INR 2-3) is preferred over a DOAC for this specific indication given the lack of DOAC trial evidence; repeat echocardiography at 3 months and consider stopping if the thrombus has resolved.

Atrial fibrillation, preferred approach dual-pathway therapy — a DOAC (apixaban, rivaroxaban, dabigatran, or edoxaban) plus a single P2Y12 inhibitor, clopidogrel preferred — omitting ASA as early as the first day after PCI and by 1 week in most patients.^[10]

Reserve triple therapy (ASA plus a P2Y12 inhibitor plus an oral anticoagulant) for patients at especially high ischemic risk (e.g., stent thrombosis, complex multivessel PCI), and only for the shortest effective period — typically up to 1 week and rarely beyond 1 month — given the substantial added bleeding risk.^[3]

Beyond the initial antithrombotic period (up to 12 months after PCI), continue oral anticoagulant monotherapy at standard stroke-prevention dosing in most patients.

Non-Pharmacologic Treatment

Refer every patient to a structured cardiac rehabilitation program before or shortly after discharge — an exercise-based, multidisciplinary program that reduces mortality and improves quality of life; referral should not be left to "if the patient asks."^[1]
Prescribe an individualized aerobic and resistance exercise program once cleared — generally about 150 minutes of moderate-intensity aerobic activity per week (roughly 30-45 minutes, 3-5 times weekly) — adjusted for age, fitness level, and any residual LV dysfunction.
Counsel on a Mediterranean-style or similarly cardioprotective dietary pattern, with specific attention to sodium restriction if hypertensive or with residual LV dysfunction.
Offer intensive smoking cessation support (counselling plus pharmacotherapy) starting during the admission and reinforced at every subsequent visit — one of the highest-yield interventions available.
Target sustained 5-10% weight loss where BMI or waist circumference exceed the treatment-target thresholds; nutritional counselling supports this.
Screen for and address psychosocial issues — depression, anxiety, and reduced social support are all common after MI and all affect adherence and outcomes; offer cognitive behavioural therapy or refer for pharmacotherapy when indicated.
Provide sublingual nitroglycerin with clear instructions for use in the setting of recurrent chest discomfort, and equally clear instructions on when that discomfort instead warrants calling emergency services.
Offer annual influenza vaccination and ensure pneumococcal and other routine vaccinations are up to date.
Counsel that resumption of sexual activity is generally safe once the patient can tolerate mild-to-moderate exertion (roughly climbing 2 flights of stairs) without symptoms, and that phosphodiesterase-5 inhibitors are contraindicated with nitrate use.
Support medication adherence directly — blister packaging/dosette use, synchronized refills, and a specific pharmacist follow-up call in the first weeks after discharge all measurably reduce early nonadherence, which is highest for the P2Y12 inhibitor specifically.

Pharmacologic Treatment Options

The pillars of post-MI secondary-prevention pharmacotherapy

Antiplatelet therapy

ASA indefinitely, plus a P2Y12 inhibitor for a risk-adjusted duration.

Beta-blocker

Started in every patient without contraindication; ongoing need reassessed after 1 year if LV function is preserved.

ACE inhibitor or ARB

Started early and continued indefinitely, with the greatest benefit in reduced LV function.

Statin

High-intensity for every patient regardless of baseline LDL-C, escalated with ezetimibe and a PCSK9 inhibitor as needed.

Mineralocorticoid receptor antagonist

Added when LVEF ≤40% plus heart failure or diabetes, on top of the other four pillars.

Drug / intervention	Role	Dose / use	Important adverse effects	Teaching points
ASA Preferred	Antiplatelet backbone, all post-MI patients	81 mg PO daily, indefinitely	GI upset, bleeding, rare bronchospasm	Continue indefinitely regardless of any later change to the P2Y12 inhibitor.
Ticagrelor Preferred	1st-line P2Y12 inhibitor, standard or extended DAPT	90 mg PO BID (12-month DAPT); 60 mg PO BID if continuing beyond 12 months	Bleeding, dyspnea, bradyarrhythmias	Co-equal 1st-line choice with prasugrel. The 60 mg dose is specific to extended-duration therapy.
Prasugrel Preferred	1st-line P2Y12 inhibitor after PCI	10 mg PO daily (5 mg if age ≥75 or weight ≤60 kg)	Bleeding, especially age >75, weight under 60 kg, prior stroke/TIA	Contraindicated with prior stroke/TIA. Do not use together with an oral anticoagulant.
Clopidogrel Alternative	P2Y12 inhibitor when ticagrelor/prasugrel are not an option, or an oral anticoagulant is also required	75 mg PO daily	Bleeding, rash, purpura	Preferred P2Y12 partner for dual-pathway or triple antithrombotic therapy.
Metoprolol Preferred	Beta-blocker, started in-hospital	Titrate to resting heart rate 50-60 bpm	Bradycardia, hypotension, fatigue	Reassess ongoing need at 1 year if LVEF ≥50% and no other indication.
Carvedilol Preferred	Beta-blocker of choice when LVEF is reduced	3.125 mg PO BID initial, double no sooner than every 2 weeks to 25 mg PO BID target	Bradycardia, hypotension, dizziness, fatigue	Preferred over a beta-1-selective agent when heart failure with reduced EF coexists.
Ramipril Preferred	ACE inhibitor, within 24-48h of MI, continued indefinitely	1.25-2.5 mg PO BID initial, target 5 mg BID or 10 mg daily	Cough, hyperkalemia, hypotension, rare angioedema	Continue indefinitely, even with preserved LV function.
Candesartan Alternative	ARB when ACE-inhibitor cough develops	4-8 mg PO daily initial, titrated up per heart failure dosing guidance	Hyperkalemia, hypotension	Do not combine with an ACE inhibitor.
Atorvastatin (high-intensity) Preferred	Statin, every post-MI patient regardless of baseline LDL	40-80 mg PO daily, started before discharge	Myalgia, transaminase elevation	High-intensity statin is mandatory, not reserved for elevated LDL.
Ezetimibe Alternative	Add-on when LDL-C remains ≥1.8 mmol/L on maximally tolerated statin	10 mg PO daily	Mild GI upset, myalgia	First escalation step, before a PCSK9 inhibitor.
Evolocumab Special situation	Add-on when LDL-C remains ≥1.8 mmol/L on statin plus ezetimibe	140 mg SC every 2 weeks, or 420 mg SC monthly	Injection-site reaction	Alirocumab and inclisiran are alternative agents in this class.
Eplerenone Special situation	Mineralocorticoid receptor antagonist when LVEF ≤40% plus heart failure or diabetes	25 mg PO daily initial, target 50 mg daily	Hyperkalemia	Requires baseline and follow-up potassium/renal monitoring, and concurrent ACE inhibitor/ARB plus beta-blocker.
Colchicine Special situation	Anti-inflammatory secondary prevention for residual risk on optimized standard therapy	0.5 mg PO daily	GI upset (usually dose-limiting), rare myelosuppression at toxic levels	Avoid if eGFR under 30 mL/min/1.73m2 or with a strong CYP3A4/P-glycoprotein inhibitor.
Apixaban Special situation	Oral anticoagulation for concomitant atrial fibrillation after PCI/ACS	5 mg PO BID (2.5 mg BID if 2 of: age ≥80, weight ≤60 kg, SCr ≥133 micromol/L)	Bleeding	Preferred DOAC in the dual-pathway strategy, paired with clopidogrel; ASA omitted early.
Warfarin Special situation	Oral anticoagulation for LV thrombus, preferred over a DOAC for this specific indication	Dose-adjusted to a target INR of 2-3	Bleeding	Repeat echocardiography at 3 months; consider stopping once the thrombus resolves.
Varenicline Preferred	Smoking cessation pharmacotherapy	0.5 mg PO daily x3 days, then 0.5 mg PO BID x4 days, then 1 mg PO BID	Nausea, vivid dreams, insomnia	Safe to start during the post-MI admission; do not withhold on cardiovascular grounds.

Special Populations

Pregnancy

Most patients in this chapter are past the acute event, so the relevant pregnancy question is usually how to manage a patient with a prior MI who is pregnant or planning pregnancy, rather than a new peripartum MI (covered in Acute Coronary Syndromes). ACE inhibitors, ARBs, and statins are contraindicated in pregnancy and should be stopped before conception whenever feasible, with the indication reassessed and a pregnancy-appropriate alternative substituted where one exists. Low-dose ASA (81 mg/day) can be continued. If a P2Y12 inhibitor is still required, clopidogrel is preferred given more available safety experience than ticagrelor or prasugrel. If an oral anticoagulant is required (LV thrombus or atrial fibrillation), low molecular weight heparin is generally preferred over warfarin (teratogenic) or a DOAC (limited pregnancy safety data); this requires coordinated obstetric/cardiology/pharmacy management. Beta-blockers can generally be continued.

Breastfeeding

ASA and beta-blockers at usual secondary-prevention doses are considered compatible with breastfeeding. Clopidogrel, statins, and ACE inhibitors/ARBs have limited breastfeeding safety data — discuss the specific agent and clinical urgency with the treating team rather than assuming one answer applies to every drug in this chapter.

Pediatric

Not applicable — myocardial infarction is exceptionally rare in children and is managed individually by pediatric cardiology; the secondary-prevention framework, dosing, and evidence in this chapter are written for adults.

Renal impairment

Reduce or avoid mineralocorticoid receptor antagonists at eGFR <30 mL/min/1.73m2 given hyperkalemia risk. Reduce DOAC doses per each product's specific renal criteria (see Drug Tables) — apixaban, rivaroxaban, dabigatran, and edoxaban each have distinct rules. Avoid colchicine at eGFR <30 mL/min/1.73m2, and note reduced benefit in the pivotal trial at eGFR <60 mL/min/1.73m2.^[9] ACE inhibitor/ARB and eplerenone/spironolactone dosing all require closer potassium and creatinine monitoring as renal function declines.

Hepatic impairment

Use statins cautiously with active liver disease and monitor transaminases if clinically indicated. Warfarin requires closer INR monitoring given impaired synthesis of clotting factors. Most antiplatelet agents require no specific hepatic dose adjustment, but bleeding risk should be reassessed in significant hepatic dysfunction.

Older adults

Reduce prasugrel to 5 mg daily at age ≥75 (or favour ticagrelor/clopidogrel instead), and weigh bleeding risk carefully before any extended-DAPT decision. Start ACE inhibitor/ARB and beta-blocker titration at lower doses with more gradual up-titration. Reassess the overall regimen periodically for deprescribing opportunities as frailty, renal function, and bleeding risk evolve — polypharmacy itself is a modifiable risk factor for adverse events in this population.

Monitoring & Follow-Up

Schedule the first follow-up visit within 1-2 weeks of discharge specifically to reconcile medications, confirm the P2Y12 inhibitor duration plan, and check for early adverse effects or affordability barriers to any of the pillar drug classes. Recheck fasting lipids 4-6 weeks after starting or changing lipid-lowering therapy, then at least annually. Recheck creatinine and potassium 1-2 weeks after starting or up-titrating an ACE inhibitor, ARB, or mineralocorticoid receptor antagonist, then periodically once stable, and again after any dose change or intercurrent illness causing volume depletion. Reassess LVEF at the guideline-specified interval (see Assessment & Diagnosis) to confirm recovery, guide continued mineralocorticoid receptor antagonist use, and determine ICD-referral timing. Confirm cardiac rehabilitation attendance and screen for depression/anxiety at follow-up visits, not only at discharge. At the 12-month mark specifically, revisit both the DAPT-duration decision and the beta-blocker-duration decision as distinct, deliberate checkpoints rather than allowing either to continue by inertia alone. Reinforce smoking-cessation status, home blood-pressure readings, and influenza vaccination at every visit.

Treatment Failure / Next Step

Recurrent angina or objective ischemia despite an optimized regimen: confirm adherence first, then reassess for restenosis, a new lesion, or incomplete revascularization with repeat angiography.
LDL-C not at target despite high-intensity statin: confirm adherence and the actual dose taken, then add ezetimibe, then add a PCSK9 inhibitor (or inclisiran) if still above target — do not skip the ezetimibe step.
Suspected statin intolerance: before abandoning the statin class, try a lower dose, an alternate statin, or non-daily dosing; add ezetimibe, a PCSK9 inhibitor, or bempedoic acid if a meaningful statin dose still cannot be tolerated.
Blood pressure not at target on an ACE inhibitor/ARB plus beta-blocker: confirm adherence and sodium intake, then add a further agent per Hypertension rather than simply pushing the ACE inhibitor/ARB beyond its target dose.
Persistent smoking despite counselling: escalate to combination pharmacotherapy (varenicline plus nicotine replacement) and refer to an intensive cessation program.
Early or unexplained P2Y12 inhibitor nonadherence identified by the pharmacy: identify the specific cause (cost, side effect, misunderstanding) and contact the prescriber before any change — never stop or substitute a P2Y12 inhibitor unilaterally given the stent-thrombosis risk.
New atrial fibrillation diagnosed in a patient already on an antiplatelet regimen: transition to the dual-pathway (or, rarely, short triple-therapy) anticoagulation strategy in the Choose Initial Treatment algorithm, in consultation with cardiology.

Common Errors to Avoid

Allowing dual antiplatelet therapy to lapse — or letting a patient stop it — without confirming this was a deliberate, guideline-concordant plan; unplanned early discontinuation carries a real stent-thrombosis risk.
Stopping a chronic beta-blocker in a preserved-EF patient unilaterally based on newer trial evidence without cardiology input — the evidence supports not routinely continuing indefinitely in this specific group, but interruption of an already-established beta-blocker has not itself been shown to be safe.
Withholding or under-titrating an ACE inhibitor/ARB or beta-blocker for a modestly low but hemodynamically tolerated blood pressure or heart rate without attempting cautious up-titration first.
Starting or up-titrating a mineralocorticoid receptor antagonist without checking baseline potassium/renal function, or without rechecking within about a week.
Defaulting to triple therapy (ASA plus a P2Y12 inhibitor plus an oral anticoagulant) for a patient with atrial fibrillation and a recent PCI instead of the now-preferred dual-pathway approach.
Missing colchicine's contraindications — significant renal impairment, active hepatic/biliary disease, or a strong CYP3A4/P-glycoprotein inhibitor — when considering it for residual inflammatory risk.
Recommending a nonselective NSAID for musculoskeletal pain in a post-MI patient without considering atherothrombotic risk; if an NSAID is truly needed, naproxen carries the most favourable cardiovascular safety signal among the options studied.
Skipping depression/anxiety screening — a common, undertreated post-MI complication that independently affects both adherence and cardiovascular outcomes.
Not confirming a cardiac rehabilitation referral was actually made, or not following up on whether the patient attended.
Assuming statin intolerance is a true class effect without first trying a lower dose, an alternate statin, or non-daily dosing.
Skipping ezetimibe and jumping straight to a PCSK9 inhibitor, or conversely treating ezetimibe alone as sufficient when LDL-C remains well above target — the escalation is stepwise, not either/or.

Clinical Decision Algorithm

Antiplatelet therapy and DAPT duration after MI

Post-MI: PCI with stent performed, or medically managed without stent

ASA 81 mg PO daily indefinitely, plus a P2Y12 inhibitor (ticagrelor or prasugrel preferred; clopidogrel if not an option) started at diagnosis

At the 12-month mark, assess bleeding risk and ischemic risk as a deliberate checkpoint

High bleeding risk (prior major bleed, oral-anticoagulant need, advanced CKD, anemia/thrombocytopenia)

Short DAPT: stop the P2Y12 inhibitor at 1-3 months, then single antiplatelet monotherapy indefinitely^[3]

Standard risk

Continue DAPT to 12 months, then ASA monotherapy indefinitely

High ischemic risk, low bleeding risk (recurrent MI, diabetes with prior stent thrombosis, extensive multivessel disease)

Consider extended therapy beyond 12 months: ticagrelor 60 mg PO BID plus ASA, or rivaroxaban 2.5 mg PO BID plus ASA, for up to 3 years^[4]

Beta-blocker duration decision

Beta-blocker started during the index MI admission, no contraindication

Titrate to resting heart rate 50-60 bpm; reassess ongoing need at the 1-year mark

LVEF under 50%, ongoing angina/arrhythmia/hypertension, or another primary indication

Continue the beta-blocker indefinitely^[1]

LVEF ≥ 50% and no other indication

Reassess ongoing need with the prescriber — a large randomized trial found no reduction in death or reinfarction from routine indefinite use in this group^[5]

If de-escalating, taper gradually with medical guidance rather than stopping abruptly — interrupting an already-established beta-blocker has not been shown to be as safe as continuing it^[6]

Lipid-lowering escalation pathway

High-intensity statin started before discharge (atorvastatin 40-80 mg or rosuvastatin 20-40 mg)

Recheck fasting LDL-C 4-6 weeks after initiation or any dose change

LDL-C under 1.8 mmol/L (70 mg/dL) on maximally tolerated statin

Continue current regimen; recheck lipids annually

LDL-C ≥ 1.8 mmol/L (70 mg/dL) on maximally tolerated statin

Add ezetimibe 10 mg PO daily^[7]

Recheck LDL-C 4-6 weeks later

At target

Continue statin plus ezetimibe

Still ≥ 1.8 mmol/L (70 mg/dL)

Add a PCSK9 inhibitor (evolocumab, alirocumab, or inclisiran)

Atrial fibrillation or LV thrombus requiring anticoagulation after MI

New indication for oral anticoagulation after MI/PCI: atrial fibrillation or LV thrombus

LV thrombus

Warfarin, target INR 2-3 — preferred over a DOAC given limited DOAC trial evidence for this indication

Repeat echocardiography at 3 months

Thrombus resolved

Consider discontinuing warfarin

Thrombus persists

Continue warfarin; reassess with cardiology

Atrial fibrillation with recent PCI or ACS

Assess bleeding risk against ischemic/stroke risk

Preferred: dual-pathway therapy — a DOAC plus clopidogrel, with ASA omitted as early as day 1 and by 1 week in most patients^[10]

Reserve triple therapy (ASA plus clopidogrel plus an oral anticoagulant) for especially high ischemic risk only, for the shortest effective period^[3]

Transition to OAC monotherapy at standard stroke-prevention dosing by 12 months in most patients

Drug Tables

How to use this table: Doses are adult doses and require patient-specific confirmation, including renal/hepatic adjustment. Select any drug name to open its complete Pharmasist Drug Database page.

Antiplatelet agents

Drug	Dosage	Adverse effects	Drug interactions	Comments
ASA	Maintenance: 81 mg PO daily, indefinitely	Gastritis, GI ulceration/hemorrhage, rare bronchospasm, tinnitus/vertigo at high dose	Increased bleeding with heparin, warfarin, other antiplatelets, and other NSAIDs	Continue indefinitely regardless of any later change to the P2Y12 inhibitor.
Clopidogrel	High-dose lead-in (selected patients): 150 mg PO daily for 6 days Maintenance: 75 mg PO daily	Bleeding, rash, purpura, diarrhea	PPI use may modestly reduce antiplatelet efficacy; caution with other agents affecting hemostasis	Preferred P2Y12 inhibitor when combined with an oral anticoagulant, or when ticagrelor/prasugrel are contraindicated, not tolerated, or unavailable.
Prasugrel	Standard: 10 mg PO daily Age ≥75 or weight ≤60 kg: 5 mg PO daily	Increased bleeding, especially age >75, weight under 60 kg, prior stroke/TIA	Caution with other agents affecting hemostasis; avoid combining with an oral anticoagulant	Contraindicated with prior stroke/TIA. Do not start until coronary anatomy has been defined.
Ticagrelor	Standard (through 12 months): 90 mg PO BID Extended (beyond 12 months): 60 mg PO BID	Bleeding, dyspnea (may require agent switch), bradyarrhythmias	Avoid strong CYP3A4 inhibitors/inducers; increases digoxin levels	The 60 mg BID dose is specific to extended-duration therapy beyond 12 months.
Extended antithrombotic option (COMPASS regimen)	Combo (adults): Rivaroxaban 2.5 mg PO BID + ASA 81 mg PO daily	Bleeding — more than ASA alone, less than full-dose anticoagulation	Additive bleeding risk with other antiplatelet/anticoagulant agents	An alternative to extended DAPT for patients with additional vascular risk (peripheral arterial disease) or higher stroke risk; not combined with a P2Y12 inhibitor.

Beta-blockers

Start within the first few days post-MI in all patients without contraindication (reactive airway disease, HR ≤50, 2nd-/3rd-degree heart block without pacemaker, SBP under 90-100 mmHg).

Drug	Dosage	Adverse effects	Drug interactions	Comments
Metoprolol	Tartrate (immediate-release): Start low, given in 2 divided doses, titrate as tolerated Succinate (extended-release): Start low once daily, titrate as tolerated	Bradycardia, hypotension, fatigue, bronchospasm	Additive bradycardia with diltiazem/verapamil/digoxin; CYP2D6 inhibitors increase levels	Titrate at intervals of several days to weeks to a resting heart rate of 50-60 bpm.
Bisoprolol	Initial: 2.5 mg PO daily Usual target: 10 mg PO daily	Bradycardia, hypotension, fatigue	Additive bradycardia with diltiazem/verapamil/digoxin	Once-daily dosing.
Carvedilol	Initial: 3.125 mg PO BID Target: 25 mg PO BID, doubling no sooner than every 2 weeks	Bradycardia, hypotension, dizziness, fatigue, bronchospasm (non-selective)	Additive bradycardia with diltiazem/verapamil/digoxin; caution with CYP2D6 inhibitors	Preferred when heart failure with reduced ejection fraction coexists; requires slow titration.

ACE inhibitors

Start within 24-48 hours of MI unless SBP under 100 mmHg; continue indefinitely, even with preserved LV function. Use lower initial doses if the patient is also on a diuretic.

Drug	Dosage	Adverse effects	Drug interactions	Comments
Ramipril	Initial: 1.25-2.5 mg PO BID Target: 5 mg PO BID or 10 mg PO daily	Dry cough, hyperkalemia, hypotension, rare angioedema	Marked hyperkalemia risk with potassium-sparing diuretics/potassium supplements; reduced effect and renal-function risk with NSAIDs; elevated lithium levels
Perindopril erbumine	Initial: 2 mg PO daily Target: 8 mg PO daily	Dry cough, hyperkalemia, hypotension, rare angioedema	Marked hyperkalemia risk with potassium-sparing diuretics/potassium supplements; reduced effect and renal-function risk with NSAIDs; elevated lithium levels	Once-daily dosing option.
Lisinopril	Initial: 2.5 mg PO daily Target: 20-40 mg PO daily	Dry cough, hyperkalemia, hypotension, rare angioedema	Marked hyperkalemia risk with potassium-sparing diuretics/potassium supplements; reduced effect and renal-function risk with NSAIDs; elevated lithium levels

Angiotensin receptor blockers

Use when ACE-inhibitor cough develops; do not combine an ACE inhibitor with an ARB.

Drug	Dosage	Adverse effects	Drug interactions	Comments
Candesartan cilexetil	Initial: 4-8 mg PO daily Target: 32 mg PO daily	Hyperkalemia, hypotension, rare angioedema	Marked hyperkalemia risk with potassium-sparing diuretics/supplements; may elevate lithium levels
Valsartan	Initial: 20 mg PO BID Target: 160 mg PO BID	Hyperkalemia, hypotension, rare angioedema	Marked hyperkalemia risk with potassium-sparing diuretics/supplements; may elevate lithium levels	Demonstrated equivalent benefit to captopril in post-MI patients with heart failure/LV dysfunction in trial data.
Losartan	Initial: 50 mg PO daily Target: 150 mg PO daily	Hyperkalemia, hypotension, rare angioedema	Marked hyperkalemia risk with potassium-sparing diuretics/supplements; may elevate lithium levels

Mineralocorticoid receptor antagonists

For patients already on an ACE inhibitor/ARB and beta-blocker who have LVEF ≤40% plus clinical heart failure or diabetes. Requires baseline potassium/renal function and reassessment 3 and 7 days after starting or titrating, then every 1-3 months once stable.

Drug	Dosage	Adverse effects	Drug interactions	Comments
Eplerenone	Initial: 25 mg PO daily Target: 50 mg PO daily	Hyperkalemia, dizziness, diarrhea	Hyperkalemia risk with ACE inhibitor/ARB and potassium supplements; avoid strong CYP3A4 inhibitors	More selective for the mineralocorticoid receptor than spironolactone — less gynecomastia.
Spironolactone	Initial: 12.5-25 mg PO daily Target: 25-50 mg PO daily	Hyperkalemia, dehydration, gynecomastia (usually reversible)	Hyperkalemia risk with ACE inhibitor/ARB and potassium supplements	Choice between the two agents is based on tolerability (gynecomastia risk) and availability.

Lipid-lowering therapy

High-intensity statin for every post-MI patient regardless of baseline LDL-C, started before discharge; escalate stepwise if LDL-C remains ≥1.8 mmol/L (70 mg/dL).

Drug	Dosage	Adverse effects	Drug interactions	Comments
Atorvastatin (high-intensity)	Dosing: 40-80 mg PO daily	Myalgia, transaminase elevation, rare myopathy/rhabdomyolysis	CYP3A4 inhibitors (macrolides, azole antifungals, protease inhibitors, grapefruit juice) increase levels
Rosuvastatin (high-intensity)	Dosing: 20-40 mg PO daily	Myalgia, transaminase elevation, rare myopathy/rhabdomyolysis	Fewer CYP3A4 interactions than atorvastatin; may increase INR with warfarin
Ezetimibe	Dosing: 10 mg PO daily	Mild GI upset, myalgia	None clinically significant	First escalation step when LDL-C remains ≥1.8 mmol/L (70 mg/dL) on maximally tolerated statin.
Evolocumab	Dosing option 1: 140 mg SC every 2 weeks Dosing option 2: 420 mg SC monthly	Injection-site reaction, nasopharyngitis	None significant	Second escalation step, added to statin plus ezetimibe.
Alirocumab	Dosing: 75 mg or 150 mg SC every 2 weeks	Injection-site reaction	None significant	Alternative PCSK9 inhibitor to evolocumab.
Inclisiran	Initial: 284 mg SC on day 1 Repeat: 284 mg SC at 3 months, then every 6 months	Injection-site reaction	None significant	siRNA-based agent dosed twice yearly after the first two doses — a durability advantage for adherence over other PCSK9-pathway agents.
Bempedoic acid	Dosing: 180 mg PO daily	Hyperuricemia/gout, rare tendon rupture	Increases simvastatin and pravastatin levels — avoid simvastatin doses above 20 mg	An additional or alternative non-statin option, including for statin-intolerant patients.
Icosapent ethyl	Dosing: 2 g PO BID with meals (4 g/day total)	Increased bleeding risk, increased risk of atrial fibrillation	Additive bleeding risk with antiplatelet/anticoagulant therapy	For persistently elevated triglycerides (roughly 1.5-5.6 mmol/L) despite statin therapy in a patient with established cardiovascular disease.^[1]

Anti-inflammatory secondary prevention

Drug	Dosage	Adverse effects	Drug interactions	Comments
Colchicine	Dosing: 0.5 mg PO daily	GI upset (usually dose-limiting), rare myelosuppression at toxic levels	Strong CYP3A4/P-glycoprotein inhibitors (e.g., clarithromycin, cyclosporine) markedly raise levels and toxicity risk	Class 2b option for residual inflammatory risk in a patient on optimized standard secondary prevention. Avoid at eGFR <30 mL/min/1.73m2; reduced benefit was seen at eGFR <60 mL/min/1.73m2 in the pivotal trial; avoid with significant hepatic/biliary disease or severe heart failure.^[9]

Anticoagulation for atrial fibrillation or LV thrombus after MI

Dual-pathway therapy (a DOAC plus a single P2Y12 inhibitor) is now preferred over triple therapy for most patients with atrial fibrillation and recent PCI/ACS; triple therapy is reserved for especially high ischemic risk and only for the shortest effective period.

Drug	Dosage	Adverse effects	Drug interactions	Comments
Warfarin	Dosing: Individualized, dose-adjusted to target INR	Bleeding	Numerous — INR affected by diet, antibiotics, and many other drugs; requires ongoing interaction screening	Preferred over a DOAC specifically for LV thrombus given a lack of DOAC trial evidence for this indication. Target INR 2.0-2.5 if combined with antiplatelet therapy for AF plus PCI, 2-3 for LV thrombus alone.
Apixaban	Standard: 5 mg PO BID Reduced dose (2 of: age ≥80, weight ≤60 kg, SCr ≥133 micromol/L): 2.5 mg PO BID	Bleeding	Additive bleeding risk with antiplatelet/other anticoagulant therapy	Preferred DOAC in the dual-pathway strategy studied for atrial fibrillation with recent ACS/PCI.
Rivaroxaban	AF, standard: 15 mg PO daily AF, reduced renal function: 10 mg PO daily	Bleeding	Additive bleeding risk with antiplatelet/other anticoagulant therapy	Studied in both a dual-pathway atrial-fibrillation regimen and, at a different dose, the COMPASS extended-antithrombotic regimen above.
Dabigatran etexilate	Standard: 150 mg PO BID Reduced (higher bleeding risk): 110 mg PO BID	Bleeding, dyspepsia	Additive bleeding risk with antiplatelet/other anticoagulant therapy	Studied in a dual-pathway atrial-fibrillation regimen with a P2Y12 inhibitor.
Edoxaban	Standard: 60 mg PO daily Reduced dose (weight ≤60 kg, CrCl 15-50 mL/min, or a potent P-glycoprotein inhibitor): 30 mg PO daily	Bleeding	Additive bleeding risk with antiplatelet/other anticoagulant therapy	Studied in a dual-pathway atrial-fibrillation regimen with a P2Y12 inhibitor.
Dual-pathway example regimens (AF plus recent PCI/ACS)	Apixaban-based: Apixaban 5 mg PO BID (2.5 mg BID if dose-reduction criteria met) + clopidogrel 75 mg PO daily Rivaroxaban-based: Rivaroxaban 15 mg PO daily (10 mg daily if reduced renal function) + clopidogrel 75 mg PO daily Dabigatran-based: Dabigatran 110 mg or 150 mg PO BID + clopidogrel 75 mg PO daily	Bleeding — lower than triple therapy in trial data	Additive bleeding risk with any further antiplatelet/anticoagulant agent	ASA is omitted from these combinations as early as day 1 and by 1 week in most patients; clopidogrel is the preferred P2Y12 partner.

Smoking cessation pharmacotherapy

Safe to start during the post-MI admission; do not withhold on cardiovascular grounds.

Drug	Dosage	Adverse effects	Drug interactions	Comments
Varenicline	Days 1-3: 0.5 mg PO daily Days 4-7: 0.5 mg PO BID Day 8 onward: 1 mg PO BID	Nausea, vivid dreams, insomnia	None clinically significant
Bupropion (sustained-release)	Days 1-3: 150 mg PO daily Day 4 onward: 150 mg PO BID	Insomnia, dry mouth, rare seizure	Avoid with other bupropion-containing products; caution with other drugs that lower seizure threshold	Contraindicated in seizure disorder and eating disorders.
Nicotine replacement therapy	Dosing: Per product-specific dosing based on baseline cigarette use	Local irritation (patch), mouth/throat irritation (gum/lozenge), insomnia, vivid dreams	None clinically significant	Combination therapy (patch plus a short-acting form) is more effective than either alone; safe post-MI.

Depression pharmacotherapy (when indicated)

Drug	Dosage	Adverse effects	Drug interactions	Comments
Sertraline	Initial: 25-50 mg PO daily Range: Up to 200 mg PO daily	GI upset, insomnia, sexual dysfunction	Serotonin syndrome risk with other serotonergic drugs; caution with antiplatelet/anticoagulant therapy given additive bleeding risk	Preferred first-line antidepressant post-MI given the largest post-MI safety evidence base among SSRIs. Avoid tricyclic antidepressants given their proarrhythmic and anticholinergic cardiac effects.

References

2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease — Circulation, American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines (Virani SS, Newby LK, Arnold SV, et al.). Circulation 2023;148(9):e9-e119
Development and Validation of a Prediction Rule for Benefit and Harm of Dual Antiplatelet Therapy Beyond 1 Year After Percutaneous Coronary Intervention — JAMA (Yeh RW, Secemsky EA, Kereiakes DJ, et al.). JAMA 2016;315(16):1735-1749
Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology 2023 Focused Update of the Guidelines for the Use of Antiplatelet Therapy — Canadian Journal of Cardiology (Bainey KR, Marquis-Gravel G, Bhatt DL, et al.). Can J Cardiol 2024;40(2):160-181
Long-Term Use of Ticagrelor in Patients with Prior Myocardial Infarction (PEGASUS-TIMI 54) — New England Journal of Medicine (Bonaca MP, Bhatt DL, Cohen M, et al.). N Engl J Med 2015;372(19):1791-1800
Beta-Blockers after Myocardial Infarction and Preserved Ejection Fraction (REDUCE-AMI) — New England Journal of Medicine (Yndigegn T, Lindahl B, Mars K, et al.). N Engl J Med 2024;390(15):1372-1381
Beta-Blocker Interruption or Continuation after Myocardial Infarction (ABYSS) — New England Journal of Medicine (Silvain J, Cayla G, Ferrari E, et al.). N Engl J Med 2024;391(14):1277-1286
2021 Canadian Cardiovascular Society Guidelines for the Management of Dyslipidemia for the Prevention of Cardiovascular Disease in Adults — Canadian Journal of Cardiology (Pearson GJ, Thanassoulis G, Anderson TJ, et al.). Can J Cardiol 2021;37(8):1129-1150
Eplerenone, a Selective Aldosterone Blocker, in Patients with Left Ventricular Dysfunction after Myocardial Infarction (EPHESUS) — New England Journal of Medicine (Pitt B, Remme W, Zannad F, et al.). N Engl J Med 2003;348(14):1309-1321
Colchicine in Patients with Chronic Coronary Disease (LoDoCo2) — New England Journal of Medicine (Nidorf SM, Fiolet ATL, Mosterd A, et al.). N Engl J Med 2020;383(19):1838-1847
Antithrombotic Therapy after Acute Coronary Syndrome or PCI in Atrial Fibrillation (AUGUSTUS) — New England Journal of Medicine (Lopes RD, Heizer G, Aronson R, et al.). N Engl J Med 2019;380(16):1509-1524

Professional reference only. Apply clinical judgment and verify patient-specific decisions against current authoritative guidance and product information.