PHARMACOLOGICAL TREATMENT OF PATIENTS WITH ANGINA WITH NO OBSTRUCTIVE CORONARY ARTERY DISEASE (ANOCA): A SYSTEMATIC REVIEW

Abstract

Fifty-one percent of women and 33% of men with angina and ischemia on provocative testing have angina with no obstructive coronary artery disease (ANOCA). These patients have impairments in quality of life that are comparable to individuals with obstructive CAD. Clinicians generally treat ANOCA with traditional anti-anginal agents, despite prior studies demonstrating variable response to these medications. Due to these disparities, we performed a systematic review to evaluate the efficacy and safety of available pharmacological therapies for ANOCA. We systematically searched the Cochrane Central Register of Controlled Trials, Embase, MEDLINE, and the World Health Organization International Clinical Trials Registry Platform from inception to February 2017 for randomized controlled trials (RCTs) evaluating any pharmacological therapy for ANOCA, excluding coronary spasm or slow flow phenomenon. The primary outcome of interest was quality of life. Secondary outcomes included other efficacy measures (functional class, angina frequency and severity, nitroglycerin use, exercise time and time to ST depression on treadmill), and safety outcomes (drug discontinuation and adverse events). We included 28 RCTs from 410 identified studies. All included trials had high or unclear risk of bias in at least one domain. Consistent evidence of subjective and objective efficacy demonstrated support for the use of beta-blockers, angiotensin convertase enzyme (ACE) inhibitors and statins. We found conflicting evidence of subjective benefit for calcium-channel blockers and ranolazine. One trial demonstrated the efficacy of nicorandil. Other interventions, most notably nitrates, did not significantly improve either subjective or objective efficacy outcomes. Table 1 summarizes the available evidence. Significant heterogeneity and incomplete outcome reporting precluded meta-analysis. For patients with ANOCA, beta-blockers, ACE inhibitors and statins, either as monotherapy or in combination, demonstrated evidence for use as first-line agents for symptomatic angina relief. Clinicians may also consider calcium-channel blockers or ranolazine for patients with persistent symptoms despite first-line therapy; however, evidence for these interventions is less consistent.