BACKGROUNDCoronary artery disease (CAD) patients experience chest pain (CP) from cardiac and non-cardiac etiologies.OBJECTIVEProton pump inhibitor (PPI) treatment of CAD patients with atypical CP would result in less CP, as well as fewer emergency room (ER) visits for CP, medical evaluations, and hospitalizations.METHODSA randomized, prospective, placebo-controlled trial in patients with a history of severe CAD, without current ischemia, and not receiving acid reducing therapy. Patients received esomeprazole 40 mg or placebo daily added to standard cardiac medications for 6 months. The primary endpoint was percentage of patients experiencing CP.RESULTSIn 162 patients randomized, 78 received esomeprazole and 84 received placebo. Esomeprazole significantly reduced the primary endpoint of patients experiencing CP (24.4% versus 54.8%; p < 0.001). The absolute number of CP episodes and CP days was also significantly reduced. Fewer patients experienced the combined endpoint of doctor office/ER visits for CP (19.2% versus 48.8%; p < 0.001), mainly due to significantly fewer office visits for CP (14.1% versus 39.3%; p < 0.001). ER visits for CP trended less with esomeprazole (12.8% versus 22.6%; p = 0.10), as did hospitalizations for CP (14.1% versus 20.2%; p = 0.30). However, the study lacked statistical power to reach these secondary endpoints.CONCLUSIONSConcomitant esomeprazole therapy in CAD patients without active ischemia but with a history of atypical CP reduces number of patients with further CP symptoms and medical office visits for CP. Larger studies are needed to further evaluate PPI treatment on ER CP visits and hospitalizations in this patient population.