What medication should be given for chest pain in a patient with Coronary Artery Disease (CAD)?

Management of Chest Pain in Patients with Coronary Artery Disease

Sublingual nitroglycerin should be administered immediately for acute relief of chest pain in patients with coronary artery disease (CAD). 1

First-Line Treatment for Acute Chest Pain in CAD

Immediate Management

• Sublingual nitroglycerin (0.3-0.4 mg) should be administered every 5 minutes for up to 3 doses 2
• After 3 doses, assess the need for intravenous nitroglycerin if pain persists and there are no contraindications 2
• For persistent ischemia, heart failure, or hypertension, intravenous nitroglycerin is indicated 2

Important Contraindications

• Do not administer nitroglycerin if patient has recently taken phosphodiesterase inhibitors:
  • Within 24 hours of sildenafil or vardenafil
  • Within 48 hours of tadalafil 2
• Nitroglycerin is contraindicated in patients with hypertrophic obstructive cardiomyopathy 2

Second-Line Treatments

If chest pain persists despite nitroglycerin:

Beta-Blockers

• Initiate oral beta-blockers within 24 hours if no contraindications exist (heart failure, low-output state, risk for cardiogenic shock) 2
• Preferred agents for CAD with heart failure: metoprolol succinate, carvedilol, or bisoprolol 2, 3
• Avoid intravenous beta-blockers when risk factors for shock are present 2

Calcium Channel Blockers (CCBs)

• Use non-dihydropyridine CCBs (verapamil, diltiazem) for recurrent ischemia when:
  • Beta-blockers are contraindicated
  • No left ventricular dysfunction exists
  • No increased risk for cardiogenic shock 2
• For coronary artery spasm, long-acting CCBs and nitrates are recommended 2
• Important caution: Immediate-release nifedipine is contraindicated without concurrent beta-blocker therapy 2

Special Considerations

For Vasospastic Angina

• First-line: Calcium channel blockers (e.g., verapamil 40 mg BID, uptitrated as needed)
• Second-line: Add long-acting nitrate (e.g., isosorbide mononitrate 10 mg BID)
• Third-line: Consider nicorandil if available 2

For Microvascular Angina

• Beta-blockers (e.g., carvedilol 6.25 mg BID, uptitrated as needed) 2
• Sublingual nitroglycerin as needed for acute symptoms 2

Common Pitfalls and Caveats

1. Do not rely on nitroglycerin response for diagnosis: Relief of chest pain with nitroglycerin does not reliably distinguish between cardiac and non-cardiac chest pain 4, 5. In one study, nitroglycerin relieved chest pain in 35% of patients with active CAD and 41% of patients without active CAD 4.

2. Patient education is critical: Many CAD patients (37% in one study) are not prescribed sublingual nitroglycerin despite guidelines recommending it, and only 43% of those prescribed receive proper instruction 6. Ensure patients:

   • Keep nitroglycerin available at all times
   • Know to call emergency services if chest pain is unrelieved after 3 doses

3. Consider intravenous nitroglycerin for refractory angina: For patients with chest pain refractory to multiple doses of sublingual nitroglycerin, intravenous nitroglycerin can be effective in approximately 85% of cases 7.

4. NSAIDs (except aspirin) should be discontinued during management of chest pain in CAD patients due to increased risk of major adverse cardiac events 2.

By following this evidence-based approach to chest pain management in CAD patients, clinicians can effectively relieve symptoms while reducing morbidity and mortality associated with coronary ischemia.