Makindo Medical Notes

Beta blockers, particularly non-selective ones, are avoided as they can exacerbate coronary artery spasms by allowing unopposed alpha-adrenergic receptor activity.

About Variant (Prinzmetal) Angina

• A type of chest pain associated with coronary artery spasms.
• Can cause transient chest pain and ST-segment elevation on ECG.

Aetiology

• Focal or diffuse coronary vasospasm leading to a temporary reduction in blood flow.
• 75% of cases may have a fixed atherosclerotic lesion.
• Can also occur in patients with normal coronary arteries.
• Hyperreactivity of the coronary artery smooth muscle is often implicated.

Clinical Features

• Chest Pain: Severe, often occurs at rest, typically in cycles, and is more common at night or in the early morning.
• Duration: Usually short-lived, lasting less than 15 minutes.
• Relief: The pain often resolves spontaneously or with the use of nitroglycerin.
• Associated Symptoms: Palpitations, dyspnoea (shortness of breath), dizziness.

Differential Diagnosis

• Ischaemic heart disease (IHD)

Investigations

• Bloods: FBC, U&E, LFTs, Troponin to rule out myocardial infarction.
• Electrocardiogram (ECG): Shows ST-segment elevation that promptly responds to sublingual nitrates.
• Coronary Angiography: The definitive test—displays coronary vasospasm. Spasm and chest pain may be provoked with IV ergonovine or acetylcholine.
• Holter Monitoring: May reveal episodes of ST-segment elevation during symptomatic periods.

Management (Treat as Acute Coronary Syndrome)

• Short-acting Nitrates: Sublingual glyceryl trinitrate (GTN) or nitroglycerin (NTG) to relieve acute chest pain episodes.
• Beta blockers: Generally avoided due to risk of exacerbating spasms.
• Calcium Channel Blockers: Diltiazem or verapamil are effective in managing symptoms.
• Long-acting Nitrates: Proven to be helpful in preventing recurrence of spasms.
• Risk Management: Encourage smoking cessation, control lipid levels, and avoid triggers such as stress and cold exposure.
• Statins: May be used to stabilize plaques if underlying atherosclerosis is present.
• Treat Coexisting Cardiac Diseases: Address any additional cardiac conditions as necessary.