Ischemic Cardiomyopathy

Ischaemic cardiomyopathy is left ventricular systolic dysfunction (ejection fraction 40% or less) caused by coronary artery disease, from infarction, hibernation or chronic ischaemia. It is the commonest cause of heart failure with reduced ejection fraction in developed countries.

Mechanisms: infarct scar, hibernating and stunned myocardium, adverse remodelling and secondary mitral regurgitation.

Risk factors are the same as for coronary disease.

Prognosis: 5 year mortality of 40 to 50% with symptomatic disease. Sudden death from ventricular arrhythmia is common.

• Exertional dyspnoea, fatigue, orthopnoea, oedema, angina, palpitations.
• Prior infarction or revascularisation.
• Displaced apex, third heart sound, mitral regurgitation murmur, raised venous pressure.
• Ventricular arrhythmia, syncope.

• ECG: Q waves, left bundle branch block, arrhythmias. BNP or NT proBNP raised.
• Echocardiography: dilated left ventricle, regional wall motion abnormalities, ejection fraction, mitral regurgitation.
• Coronary angiography or CT angiography for anatomy.
• Viability assessment (cardiac MRI with late gadolinium enhancement, dobutamine echo, PET, SPECT) if revascularisation is considered. Transmural scar over 50% predicts poor recovery.
• Holter monitoring and electrophysiology as indicated.

Guideline directed medical therapy

• Sacubitril/valsartan 24/26 mg twice daily titrated to 97/103 mg (or ACE inhibitor: ramipril 2.5 to 10 mg daily; or ARB).
• Beta blocker: bisoprolol 1.25 to 10 mg daily, carvedilol 3.125 to 25 mg twice daily, metoprolol succinate 12.5 to 200 mg daily.
• Mineralocorticoid antagonist: spironolactone 25 to 50 mg or eplerenone 25 to 50 mg.
• SGLT2 inhibitor: dapagliflozin 10 mg or empagliflozin 10 mg daily.
• Loop diuretics for congestion; ivabradine (heart rate over 70 in sinus rhythm); hydralazine with isosorbide dinitrate where appropriate; vericiguat for worsening failure.
• Aspirin 75 to 100 mg, high intensity statin.

Revascularisation

Coronary bypass improves long term survival in multivessel disease with ejection fraction 35% or less (STICH). PCI for suitable anatomy with viability.

Devices

• ICD for ejection fraction 35% or less after at least 3 months of therapy (40 days after infarction, 90 days after revascularisation).
• Cardiac resynchronisation therapy for left bundle branch block with QRS 150 ms or more.
• Surgical mitral repair, ventricular reconstruction in selected patients.

Advanced

Left ventricular assist device or transplantation. Cardiac rehabilitation, vaccinations, sodium and fluid advice, depression treatment.