Drugs for Secondary Prevention of MI

Ensure the following medicines are prescribed as secondary prevention post-MI as appropriate:

Antiplatelet drugs

Refer to the Secondary Prevention of Coronary Heart Disease and Stroke – Antiplatelet guideline

Beta-blockers

Within 12-48 hours and certainly prior to discharge all patients without contraindications should be considered for beta-blockers.

Bisoprolol oral 2.5–5mg daily

Or if evidence of heart failure (once stabilised):

Carvedilol oral 3.125mg twice daily or

Bisoprolol oral 1.25mg daily, then slowly up-titrated

Avoid beta-blockers in patients with asthma, 2^nd or 3^rd degree heart block, bradycardia <50bpm, symptomatic hypotension or SBP <90mmHg, pulmonary oedema, concomitant verapamil (caution with digoxin).

Alternative options are:

• Cautious test dose with a short-acting beta-blocker such as metoprolol oral 12.5mg or 25mg twice daily (which may be switched to an alternative beta-blocker if tolerated).
• A rate limiting calcium antagonist e.g. verapamil or diltiazem instead of a beta-blocker should be considered in patients with asthma provided no evidence of cardiac failure, severe LVSD, symptomatic hypotension or 2^nd or 3^rd degree heart block.

Statins

Refer to the Management of Hyperlipidaemia guideline.

ACE inhibitors (ACEI)

Unless contraindicated, ACEI should be commenced in all patients with an MI (those with an anterior MI should, if possible, be commenced within 24 hours).

Use with caution:

• Symptomatic hypotension
• Impaired renal function (creatinine 200-250micromol/L)

Contraindicated:

• Severe aortic stenosis (discuss with consultant)
• Bilateral renal artery stenosis

Ramipril oral 1.25mg or lisinopril 2.5mg (as a test dose), then titrate as tolerated.

For ACEIs:

• Check U&Es 1-2 weeks after commencing (usually arranged with GP at discharge) to assess renal function.
• Gradually increase dose and titrate to maximum tolerated dose, unless symptomatic hypotension or deterioration in renal function. 
• If ACEI not tolerated due to cough, substitute with an angiotensin II receptor blocker (consider losartan or candesartan).

Calcium-channel blockers

May be considered if indicated for anginal symptoms

Amlodipine oral 5mg daily (increased to 10mg daily if needed). This is the preferred calcium-channel blocker for patients on a beta-blocker, and can be used safely post-MI or in LVSD.

or

Verapamil / Diltiazem (see BNF for dosing): in patients with asthma (where beta-blockers are contraindicated) oral verapamil or diltiazem should be considered, provided there has been no evidence of cardiac failure, severe LVSD, symptomatic hypotension or 2^nd or 3^rd degree heart block. N.B. Concomitant verapamil and beta-blockers should be avoided.

Nitrates

May be considered if indicated for anginal symptoms

Isosorbide mononitrate oral 10–40mg twice daily (prescribe 8am and 2pm). Nitrate free period recommended (usually at night) to avoid developing tolerance.

Eplerenone

Patients with heart failure complicating acute MI or LVEF <40%, should be considered for treatment with eplerenone oral 25mg daily.

To be titrated up to 50mg daily preferably within 4 weeks taking into account the potassium level. Major contraindications are hyperkalaemia and renal failure.

Glyceryl trinitrate spray

All patients should be discharged with glyceryl trinitrate spray 400micrograms unless contraindicated.