The percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) coronary artery disease is difficult, the success rate is low, and the incidence of re-occlusion and restenosis is high. With the wide application of imaging technology represented by intravascular ultrasound (IVUS), the success rate of CTO PCI has been significantly improved. Drug-coated balloons (DCB), as a treatment without metal implantation, has lower lumen loss and no significant increase in the rate of revascularization. Through IVUS measurement of vascular lumen after CTO opening, appropriate instruments can be selected for adequate dilation, and appropriate treatment methods can be selected according to different lumen structures. Therefore, the purpose of this study was to evaluate the clinical effect of IVUS-guided DCB therapy on CTO lesions.

Inclusion Criteria:

1. Over the age of 18, male or female;
2. Patients who meet the diagnostic criteria for coronary heart disease, have clinical symptoms and seek interventional treatment;
3. Coronary angiography confirmed that the blood vessels met the diagnostic criteria of CTO;
4. Sign informed consent and be willing to undergo follow-up for at least 12 months.

Exclusion Criteria:

1. Patients with severe contrast allergy who cannot tolerate coronary angiography;
2. Patients known allergy to drug balloon coating;
3. Patients who is pregnant or breastfeeding;
4. Bleeding or other diseases, such as digestive tract ulcers, blood system diseases, etc., limit the use of platelet aggregation inhibitors and anticoagulation therapy;
5. Patients with cardiac shock;
6. Patients with a life expectancy of less than 1 year;
7. Other situations deemed unsuitable for inclusion by the researcher.

Among CTO lesions previously treated with DCB, the incidence of restenosis was 11.8%, with a sample size of 90-110. This is an observational study on the treatment of CTO, and all patients with CTO lesions were nonselectively enrolled. Continuous enrollment of CTO patients from September 2023 to August 2024 (an estimated 100 cases) was designed to observe the clinical effect of IVUS-directed DCB therapy on CTO lesions.