Targeted pharmacotherapy of vasospastic angina can be difficult in the absence of a defined etiology. For that reason, clinicians should select an agent based on and guided by patient-specific factors. These include tolerability, adverse effects, drug-drug, and drug-disease interactions. Incidence of episodes of angina have been found to decrease with smoking cessation; therefore, patients should be advised to quit smoking.
Overall, evidence supporting pharmacotherapeutic options for the treatment of vasospastic angina remains limited. Recommendations for several classes of agents available to treat vasospastic angina are summarized in the 2014 non-ST-segment elevation ACS guidelines.2 The calcium channel blockers (CCBs) are the currently recommended first-line agents to treat and prevent vasospastic angina (Table 1), especially in patients with comorbid atrial fibrillation, hypertension, or heart failure with preserved ejection fraction. When initiating treatment with CCBs in patients newly diagnosed with vasospastic angina, a moderate to high dose—verapamil 240–480mg/day, diltiazem 180–360mg/day, or nifedipine ER 60–120mg/day—may be recommended. Use CCBs with caution in those with heart failure with reduced ejection fraction, hypotension, conduction abnormalities, and hepatic dysfunction.
For patients who respond poorly to CCBs, agents such as the nitrates, the HMG-CoA reductase inhibitors (statins), or alpha1-adrenergic receptor antagonists may be used (Table 2).
Limited evidence is available for the alternative pharmacotherapeutic agents ranolazine, bosentan, and cilostazol (Table 3).
Beta-adrenergic receptor antagonists and aspirin should be avoided. Two clinical studies in 133 patients found propranolol to be ineffective, and may actually increase the frequency of angina attacks, exacerbating coronary vasospasm. Similarly, the use of aspirin was found in 3 studies of more than 3,200 patients to fail to reduce morbidity or attacks of recurrent angina. In fact, high-dose aspirin may be associated with increased incidence of angina attacks.
Prior to initiating therapy for vasospastic angina, clinicians should advise patients to modify their risk factors, such as stopping smoking. Other patient-specific factors to consider are drug-drug interactions, drug-disease interactions, and adverse effects. To prevent morbidity following treatment, safety and efficacy should be frequently evaluated. Since symptoms of vasospastic angina can overlap those of a myocardial infarction, patients should be advised to contact emergency services if their symptoms are not alleviated with nitroglycerin.
1. Harris JR, Hale GM, Dasari TW, Schwier NC. Pharmacotherapy of vasospastic angina. J Cardiovasc Pharmacol Ther. 2016;1-13. DOI: 10.1177/1074248416640161
2. Amsterdam EA, Wenger NK, Brindis RG, et al. 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2014;64(24):e139-228.