Peripheral arterial disease is associated with coronary artery spasm as assessed by an intracoronary acetylcholine provocation test

1. Both peripheral arterial disease (PAD) and coronary artery spasm (CAS) are associated with endothelial dysfunction. Thus, a higher incidence of CAS may be expected in patients with PAD. In the present study, we evaluated the incidence and characteristics of CAS in patients with PAD. 2. A total of 78 patients with PAD and 241 age- and gender-matched patients without PAD who had chest pain with normal coronary appearance on coronary angiograms underwent intracoronary acetylcholine (ACh) provocation test. Acetylcholine was injected into the left coronary artery in incremental doses of 20, 50 and 100 microg/min. Significant CAS was defined as a transient > 70% luminal narrowing with concurrent chest pain and/or ST segment changes. 3. Patients with PAD had a significantly higher incidence of ACh-induced significant CAS than those without PAD (60.3 vs 34.0%, respectively P < 0.001), as well as chest pain and ST segment changes during the ACh provocation test. Patients with PAD were more sensitive to lower doses of ACh and had a higher incidence of multivessel spasm than those without PAD. Multivariable logistic analysis showed that age, current smoking, PAD and myocardial bridge were independent predictors of ACh-induced significant CAS. Moreover, of these factors, PAD was the strongest independent predictor (odds ratio 4.25; confidence interval 1.33-13.54; P = 0.014). 4. In patients with chest pain, the presence of arterial disease at another site should still push the clinician towards treating the chest pain as angina, even if the coronary anatomy is normal on a coronary angiogram.