Epicardial Coronary Spasm in Women With Angina Pectoris and Unobstructed Coronary Arteries Is Linked With a Positive Family History: An Observational Study

Abstract Purpose Coronary spasm is frequently found in patients with angina and unobstructed coronaries. The pathophysiology is incompletely understood, although sex differences have been described. Often a positive family history (PFH) is encountered. We assessed the relationship between sex, coronary spasm, and a PFH for cardiovascular disease. Methods This single-center observational study recruited 415 stable angina patients with unobstructed coronaries (no stenosis >50%) between 2008 and 2011 (mean [SD] age, 62 [10] years; 38% men). Patients were referred for angiography because of signs and symptoms of myocardial ischemia. Intracoronary acetylcholine (ACh) testing was performed in all patients according to a standardized protocol. Risk factor assessment included hypertension, hypercholesterolemia, diabetes, smoking, and a PFH. The latter was defined as a first-degree relative with myocardial infarction or stroke. Statistical analysis involved comparison of categorical and continuous variables. Multivariable analysis aimed at identifying predictors for a pathologic ACh testing, microvascular spasm, and a PFH. Findings Epicardial spasm was found in 33% of patients and microvascular spasm in 30% of patients. A pathologic ACh test was more frequent in women than in men (72% vs 49%; P P  = 0.001). Among patients with epicardial spasm, women had a PFH significantly more often than men (66% vs 43%; P  = 0.006). The latter difference was not found when comparing women and men with microvascular spasm. Implications There is a female preponderance among patients with angina and unobstructed coronaries. ACh testing enables detection of coronary spasm. Epicardial spasm in women is associated with a PFH.