Routine Use of Potassium Competitive Acid Blocker vs. Guideline-Directed Gastrointestinal Protection Strategy in Acute Myocardial Infarction

Inclusion Criteria: * Patients aged 19 years or older. * Patients diagnosed with acute myocardial infarction (ST-segment elevation myocardial infarction \[STEMI\] or non-ST-segment elevation myocardial infarction \[NSTEMI\]). * Patients who underwent percutaneous coronary intervention (PCI) with drug-eluting stents (DES) or drug-coated balloons (DCB). * Patients (or their legal representatives) who understood the study risks and benefits and provided voluntary written informed consent. * Patients with suspected gastroesophageal reflux disease (GERD). Exclusion Criteria: * History of hypersensitivity (e.g., allergic reaction, anaphylactic shock) or contraindication to study drugs (potassium-competitive acid blocker \[P-CAB\] or proton pump inhibitor \[PPI\]). * Presence of active gastrointestinal bleeding. * Pregnant or breastfeeding women. * Non-cardiac life expectancy of less than 1 year or patients expected to have low compliance (as determined by the investigator's medical judgment). * Patients who refuse to participate or are unable to follow the requirements specified in the study protocol.