BACKGROUND: Translating evidence into clinical practice in the management of established atherosclerotic cardiovascular disease patients is challenging. Few quality improvement interventions have successfully improved patient care. OBJECTIVES: The main objectives are to evaluate the impact of a digitally enabled multifaceted quality improvement (QI) intervention on the control of LDL-cholesterol (LDL-C) in atherosclerotic cardiovascular disease (ASCVD). DESIGN: We designed a pragmatic 2-arm cluster randomized trial involving 28 clusters (outpatient clinics from public or private hospitals or private practices). Clusters are randomized to receive a digitally enabled multifaceted QI intervention or to routine practice (control). The QI intervention includes reminders, electronic clinical decision support algorithms, audit and feedback reports, and distribution of educational materials to health care providers, as well as electronic educational materials and app-based tools for drug adherence control, lipid profile control, and communication to participants. The primary endpoint is the LDL-C at 06 months after the intervention period. All analyses are performed following the intention-to-treat principle and take the cluster design into consideration by using individual-level regression modeling (generalized estimating equations-GEE). SUMMARY: If proven effective, this low-cost, digitally enabled multifaceted QI intervention would be highly useful in promoting optimal LDL-C control in ASCVD patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT05622929.