What is the best course of action for a patient experiencing angina (chest pain) at rest but not during exercise?

Angina at Rest Without Exertional Symptoms: Vasospastic Angina (Prinzmetal's Angina)

This presentation strongly suggests vasospastic angina (Prinzmetal's angina), which requires immediate diagnostic confirmation with ECG during symptoms showing transient ST-segment elevation, followed by first-line treatment with calcium channel blockers and long-acting nitrates—not beta-blockers, which may worsen coronary spasm. 1

Diagnostic Approach

Key Clinical Features to Confirm

• Angina occurring spontaneously at rest without preceding increase in myocardial oxygen demand, with most patients having normal exercise tolerance and potentially negative stress testing 1
• Episodes typically cluster in the early morning hours due to circadian variation, with prolonged asymptomatic periods of weeks to months between clusters 1
• Exquisite response to nitroglycerin, with rapid resolution of both symptoms and ECG changes 1
• Younger age compared to typical stable angina patients, with fewer coronary risk factors except for smoking 1

Essential Diagnostic Documentation

• The gold standard is capturing transient ST-segment elevation during chest discomfort that resolves when pain abates 1
• Continuous 12-lead ECG monitoring (in-hospital or outpatient Holter) should be performed to document ST-elevation during symptomatic episodes 1
• Coronary angiography is usually part of the workup to determine whether spasm occurs on normal vessels, non-obstructive plaques, or significant stenoses, as this guides treatment strategy 1

Provocative Testing Considerations

• Provocative tests (acetylcholine, ergonovine, or hyperventilation) can confirm vasospastic tendency but are rarely used now due to risk of refractory spasm, MI, or death 1, 2
• These tests should only be considered when: (1) attempts to document spontaneous ST-elevation have failed, (2) symptoms are highly suggestive but unconfirmed, or (3) verifying treatment efficacy in high-risk patients 1
• Nitrates and calcium channel blockers must be withdrawn well before any provocative testing 1

Treatment Strategy

First-Line Pharmacotherapy

• Calcium channel blockers at moderate to high doses are first-line therapy: verapamil 240-480 mg/day, diltiazem 180-360 mg/day, or nifedipine 60-120 mg/day 1
• Long-acting nitrates should be added, often in combination with calcium channel blockers for patients with very active disease 1
• Medication schedule should be adapted to the circadian variation in spasm episodes, with higher doses timed for early morning hours when attacks most commonly occur 1

Critical Medication Pitfall

• Beta-blockers have theoretical adverse potential and controversial clinical effect in vasospastic angina—they may worsen coronary spasm by allowing unopposed alpha-adrenergic vasoconstriction 1
• This is a critical distinction from typical exertional angina, where beta-blockers are first-line therapy 1

Immediate Symptom Management

• Sublingual nitroglycerin (0.3-0.6 mg) should be dissolved under the tongue at first sign of attack, with doses repeated every 5 minutes up to 3 tablets over 15 minutes 3
• If pain persists after 3 tablets or is different than typically experienced, prompt medical attention is mandatory as prolonged vasospasm can result in MI, high-degree AV block, life-threatening ventricular tachycardia, or sudden death 1, 3

Risk Stratification

High-Risk Features Requiring Aggressive Management

• Multivessel spasm on angiography or provocative testing 1
• Complex ventricular arrhythmias or AV block associated with ischemic episodes 1
• Syncope during chest pain episodes, suggesting severe ischemia from acute occlusion 1
• Obstructive coronary disease underlying the spasm: 39% have single-vessel disease and 19% have multivessel disease on angiography 1

Prognosis and Long-Term Outcomes

• With appropriate treatment, long-term outcome is favorable with cardiovascular death rate of 0.5% per year and MI risk of 1.2% per year 1
• However, more than one-third of patients remain symptomatic despite treatment 1
• The greater the number of diseased arteries, the higher the risk of death or MI during follow-up 1

Essential Lifestyle Modifications

• Smoking cessation is mandatory, as smoking is the predominant risk factor in vasospastic angina patients 1
• Avoid triggers: emotional stress, hyperventilation, cold exposure, and early morning exertion 1

When to Consider Revascularization

• Stent implantation has been proposed for focal refractory spasm that does not respond to maximal medical therapy 1
• However, this is reserved for highly selected cases, as the primary pathophysiology is vasomotor dysfunction rather than fixed obstruction 1

Critical Distinction from Unstable Angina

While both conditions present with rest angina, unstable angina typically shows ST-segment depression (not elevation), has elevated troponins indicating myocardial necrosis, and requires immediate hospitalization with antiplatelet therapy and early invasive strategy 4, 5. In contrast, vasospastic angina shows transient ST-elevation that resolves spontaneously or with nitroglycerin, normal troponins, and responds to vasodilators rather than antiplatelet agents 1.