Microvascular angina
Microvascular angina is angina from coronary microvascular dysfunction with no obstructive epicardial disease, part of the INOCA spectrum. It causes exertional or rest chest pain with evidence of ischemia but normal angiography, is diagnosed by tests of coronary flow reserve, and is managed with risk-factor control and antianginal therapy.
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What this article covers
- Overview
Definition: microvascular angina is angina caused by coronary microvascular dysfunction (impaired vasodilation or microvascular spasm) in the absence of obstructive epicardial coronary disease, part…
- Epidemiology
More common in women. A frequent explanation for angina with non-obstructive coronaries.
- Risk factors
Female sex (especially post-menopausal). Traditional risk factors: hypertension, diabetes, dyslipidemia, and smoking.
- Pathophysiology
Microvascular dysfunction: impaired endothelium-dependent and independent vasodilation reduces the ability to augment coronary flow (reduced coronary flow reserve).
- Clinical features
Exertional or rest angina, often with a prolonged response to rest or nitrates.
- Differential diagnosis
Obstructive coronary artery disease: exertional angina with objective ischemia, distinguished by a flow-limiting epicardial stenosis on angiography, which is absent in microvascular disease (Chronic stable angina).
- Diagnosis
Establish by demonstrating ischemia or impaired microvascular function with non-obstructive coronary arteries: the diagnostic basis is angina with objective ischemia and non-obstructive coronaries on…
- Management
First-line, aggressive risk-factor control and antianginal therapy: A statin (atorvastatin 40 to 80 mg PO daily) and blood pressure control.
- Complications
Recurrent angina and reduced quality of life.
- Prognosis
Better than obstructive disease but not benign, with excess events.
- Prevention
Blood pressure control to a target below 130/80 mmHg.
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