The central role of conventional 12-lead ECG for the assessment of microvascular obstruction after percutaneous myocardial revascularization

Guidelines report that the optimal treatment for ST-elevation myocardial infarction (STEMI) is a primary percutaneous coronary intervention (PPCI) when performed timely by trained operators. Yet, the reopening of the infarct-related artery (IRA) is not always followed by myocardial reperfusion. This phenomenon is most commonly called "no-reflow", is caused by microvascular obstruction (MVO) and is associated to a worse outcome. Electrocardiogram (ECG) is crucial for the diagnosis of STEMI, but is also useful for the assessment of MVO. In this review we summarize ECG-derived parameters associated to MVO and their prognostic relevance.