The coronary angiography-derived index of microcirculatory resistance (caIMR) can be used to provide a binary assessment whether patients（with stable angina, unstable angina, suspected myocardial ischemia, or coronary artery stenosis of less than 50%, and without cardiomyopathy or obstructive epicardial coronary artery disease） have microcirculatory dysfunction, using a cutoff value of 25.
This study aims to evaluate the binary classification performance of caIMR in two specific groups of patients: (1) those with caIMR values between 20 and 30, and (2) those with diffuse disease. We will do this by looking at differences in their Seattle Angina Questionnaire (SAQ) scores and their health outcomes over a three-year period.
Age between 18 and 80 years, regardless of gender;
Diagnosed with stable angina, unstable angina, or suspected myocardial ischemia;
targeted vessel stenosis < 50% and caIMR values between 20 and 30; or
Previously undergone percutaneous coronary intervention (PCI);
History of heart failure or myocardial infarction;
Acute myocardial infarction;
Primary or secondary cardiomyopathy;