6. Patients with de novo, in situ lesions of small coronary vessels, the length of the lesion should be ≤26mm according to visual inspection. In the small vessel cohort, the diameter of the target lesion should be ≥2.25mm and ≤2.75mm according to visual inspection, and in the very small vessel cohort, the diameter of the target lesion should be ≥2. 00mm and <2.25mm according to visual inspection.