The importance of accurate diagnosis of myocardial infarction with nonobstructive coronary arteries to prevent unnecessary coronary intervention

•Diagnosis of MINOCA (e.g. coronary spasm) is important to avoid unnecessary PCI.•Sufficient coronary dilatation is crucial, but accurate diagnosis may be still challenging.•Intravascular imaging such as IVUS or OCT can help determine the exact cause of Acute Myocardial Infarction.