What is the treatment for angina?

Treatment of Angina

All patients with angina should receive aspirin 75-150 mg daily and a statin for prognostic benefit, plus sublingual nitroglycerin for immediate symptom relief, with beta-blockers as first-line regular therapy for symptom control. 1, 2

Immediate Symptom Relief (All Patients)

• Sublingual nitroglycerin (0.3-0.4 mg) or nitroglycerin spray should be prescribed to every patient with angina for acute symptom relief and prophylactic use before activities that trigger angina 1, 2, 3
• Nitroglycerin spray offers advantages over tablets including faster onset, lower headache incidence, and effectiveness in patients with dry mouth 3
• If sublingual preparations fail to relieve symptoms, buccal nitroglycerin should be considered as it is more effective than sublingual formulations 4
• If angina does not respond to nitroglycerin, the patient should seek emergency care immediately as this may indicate myocardial infarction 2

Prognostic Medications (Reduce Mortality and Morbidity)

These medications improve outcomes and should be prescribed to all patients unless contraindicated:

• Aspirin 75-150 mg daily reduces subsequent vascular events and cardiovascular mortality 1, 2
• Statin therapy should be prescribed for all patients with documented coronary artery disease to reduce adverse ischemic events 1, 2
• ACE inhibitors should be prescribed in patients with hypertension, heart failure, left ventricular dysfunction, prior myocardial infarction, or diabetes 1, 2

Regular Symptomatic Treatment Algorithm

First-Line: Beta-Blockers

• Beta-blockers (metoprolol, atenolol, or bisoprolol) are first-line therapy and should be titrated to full dose for maintenance therapy 1, 2
• Beta-blockers are superior to calcium channel blockers in reducing exercise-induced ischemia 2
• Critical warning: Patients must not stop beta-blockers suddenly as this worsens angina; taper over four weeks if discontinuation is necessary 4, 1

Second-Line: When Beta-Blockers Fail or Are Contraindicated

If beta-blocker monotherapy at maximal dose is insufficient:

• Add a long-acting dihydropyridine calcium channel blocker (e.g., amlodipine) to the beta-blocker 1, 2
• Amlodipine 5-10 mg daily increases exercise time by 38-63 seconds and reduces angina attack rates 5

If beta-blockers are contraindicated or not tolerated:

• Use long-acting calcium channel blockers as monotherapy (verapamil or diltiazem for rate control; amlodipine or nifedipine for vasodilation) 1, 2
• Alternatively, use long-acting nitrates but must administer with a nitrate-free interval (remove patch at bedtime, reapply in morning) to prevent tolerance 1, 6
• Nitrate patches require dosages of at least 10 mg to be effective 4

Special Case: Vasospastic Angina

• High-dose calcium channel blockers are the mainstay (up to 480 mg/day verapamil, 260 mg/day diltiazem, or 120 mg/day nifedipine) 2, 7
• Sublingual nifedipine 5-10 mg can be used for acute attacks resistant to nitroglycerin 7

Third-Line Options and Refractory Angina

• Ranolazine 500-1000 mg twice daily can be added to existing therapy (beta-blockers or calcium channel blockers) and significantly reduces angina frequency and nitroglycerin use 8
• If symptoms remain uncontrolled on maximal doses of two drugs, refer to cardiology for angiography rather than adding a third drug, as evidence-based options become very limited 4, 1

Critical Medications to Avoid

• Never use short-acting dihydropyridine calcium antagonists (e.g., immediate-release nifedipine) without concurrent beta-blocker therapy due to increased risk of adverse cardiac events 1, 2
• Dipyridamole is contraindicated as it can enhance exercise-induced myocardial ischemia 1
• Chelation therapy has no evidence base and should not be used 1

Common Pitfalls

• Using three anti-anginal drugs simultaneously may provide less symptomatic protection than optimizing two drugs; always optimize dosing of existing medications before adding another 2
• Continuous 24-hour nitrate therapy causes tolerance in most patients; ensure nitrate-free intervals of 10-14 hours daily 1, 6
• Poor medication adherence is a common cause of treatment failure and must be assessed before escalating therapy 2
• Ensure patients understand proper nitroglycerin use: take at first sign of angina or prophylactically before triggering activities 1, 3

When to Refer to Cardiology

Refer patients in the following situations:

• All patients with clinically certain angina should be referred to identify whether they would benefit from prognostic investigation and revascularization 4, 1
• Symptoms uncontrolled on maximal doses of two anti-anginal drugs should prompt referral for angiography, not exercise testing 4, 1
• Diagnostic uncertainty warrants referral for clarification 4
• High-risk patients with left ventricular dysfunction should be considered for revascularization 2

Risk Factor Modification

• All patients who smoke must be advised to stop; nicotine patches can safely be used in coronary artery disease patients as part of a broader cessation strategy 4
• Blood pressure should be measured and managed according to published guidelines 4
• Cholesterol lowering with statins benefits all patients with coronary disease 4