STEMI - ST-segment Elevation Myocardial Infarction

The main symptom that initiates the diagnostic and therapeutic process for patients with suspected acute coronary syndrome is chest pain. Based on a standard 12-lead electrocardiogram (ECG), patients can be diagnosed with ST-segment elevation myocardial infarction (STEMI), which requires immediate medical treatment. Recently, wearable devices like smartwatches with ECG capabilities have opened new pathways for cardiac triage, but their diagnostic precision and technical viability in a real, unselected Emergency Department setting need to be confirmed. The primary objective of this prospective, observational study is to compare the diagnostic capacity of a 9-lead ECG obtained with a smartwatch against the standard 12-lead ECG for diagnosing STEMI in patients consulting for chest pain. During the study, patients evaluated by the on-call cardiologist for ischemic chest pain will undergo their standard care. In addition to the standard 12-lead ECG, a 9-lead ECG will be sequentially recorded using a smartwatch. This is an observational study, meaning the smartwatch recording will not cause any delay in clinical action or negatively impact the patient's standard treatment. Specifically, the study aims to: * Analyze the diagnostic agreement between expert cardiologists when blindly and independently classifying the smartwatch recordings versus the standard ECG recordings as "STEMI" or "non-STEMI". * Evaluate the technical feasibility of using the smartwatch in an Emergency Department setting by assessing the percentage of unreadable records due to artifacts.

Despite the success of restoration of epicardial blood flow by the primary percutaneous coronary intervention (PPCI), approximately one half of patients with ST-segment elevation myocardial infarction (STEMI) have failed myocardial reperfusion, namely microvascular dysfunction. Previous studies have shown that coronary microvascular damage significantly impacts the prognosis of patients with STEMI. Therefore, restoration of microvascular function is quite important during the PPCI procedures. Recent clinical trials found that nicorandil, a hybrid ATP-sensitive potassium channel opening agent, improved microvascular function, prevented no-reflow phenomenon, and had beneficial cardioprotective effects in patients receiving PPCI. However, there was a lack of evidence on the protective effects of nicorandil on microvascular function. The coronary angiography-derived IMR (AMR) is a novel wire-free technology developed for fast computation of IMR in patients undergoing coronary angiography, thereby enabling the quantification of coronary microcirculation of patients. This study is aimed to investigate the effects of nicorandil on microvascular dysfunction as evaluated by AMR in patients with STEMI.