Research advances in diagnostic methods for myocardial ischemia-reperfusion without reflow

In recent years, the incidence and mortality of cardiovascular events are increasing. Acute coronary syndrome (ACS), as one of the acute and critical illnesses of cardiovascular system, has an aggressive onset and a high mortality rate. Percutaneous coronary intervention is an effective treatment for patients with ACS, which can open the occluded vessels in time, realize myocardial reperfusion, and significantly reduce the mortality rate. However, the occurrence of coronary artery no-reflow after hemodialysis is an important cause of increased mortality in ACS. Early diagnosis of no-reflow is critical for urgent reperfusion therapy. Coronary angiography is the most direct method to diagnose no-reflow in the catheterization laboratory and is one of the commonly used diagnostic measures in clinical practice at this stage. Intracoronary physiologic assessment is based on the principles of coronary hemodynamics, which assesses the blood supply function of the heart by measuring coronary blood flow velocity and coronary pressure. In addition, the rise of many non-invasive cardiac imaging techniques has provided a broad application prospect for the diagnosis of no-reflow. In this article, we systematically summarize and analyze the recent advances and current challenges of diagnostic methods such as TIMI flow grading, corrected TIMI frame rate, coronary flow reserve, microcirculatory resistance index, electrocardiography, and cardiovascular magnetic resonance imaging, with the aim of providing a reference for early diagnosis and comprehensive assessment of anelectasis.