Comparison Between Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers in Patients with Unstable Angina with Preserved Left Ventricular Systolic Function

Background: We investigated the clinical results of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) treatment in patients with unstable angina (UA) with preserved left ventricular systolic function who underwent percutaneous coronary intervention (PCI) due to uncertainty regarding the long-term prognosis using ACEIs or ARBs. Methods A total of 1627 UA patients with preserved left ventricular systolic function who successfully underwent PCI were enrolled. We classified those patients into two groups: the ACEI group (n=918) and the ARB group (n=709) based on discharge medications. The primary endpoint was the incidence of major adverse cardiovascular and cerebrovascular events (MACCEs), including all-cause death, nonfatal myocardial infarction (MI), stroke and target vessel revascularization (TVR), with a follow-up period of 13 months. The secondary endpoint was the occurrence of separate components of MACCEs. We applied the Kaplan–Meier method to depict survival curves, while intergroup differences were performed using the log-rank test. Multivariable Cox regression analysis was applied to assess the prognostic influence of various factors. To balance potential confounding biases derived from differences in baseline levels, propensity score matching (PSM) was used to adjust for confounders between the ACEI and ARB groups. Results After PSM, 660 pairs in each group were created. There were no differences in MACCEs (HR=0.860, 95%CI: 0.465-1.590, P =0.630), all-cause death (HR=0.334, 95%CI: 0.090-1.238, P =0.101), non-fatal MI (HR=4.929, 95%CI: 0.576-42.195, P =0.145), stroke (HR=1.049, 95%CI: 0.208-5.290, P =0.954) and TVR (HR=1.276, 95% CI: 0.537-3.031, P =0.581) between the ACEI and ARB groups. Conclusions Prognoses were comparable between ACEI or ARB treatment in UA patients who had preserved left ventricular systolic function after PCI.