• Age 18-75 years old (including threshold), gender unlimited

• acute ST-segment elevation myocardial infarction was diagnosed, and the following two criteria were met: A) ischemic chest pain lasting ≥30 min；B) ECG indicating ST-segment elevation ≥0.1 mV in two or more limb leads and/or ≥0.2 mV in two or more adjacent chest leads

• Coronary angiography confirmed that the culprit's vessel was located in the anterior descending branch, and the proximal and middle segments of the anterior descending branch were occluded (TIMI blood flow 0 or 1), Or TIMI blood flow grade 2 with obvious thrombus (TIMI thrombus score ≥ 2 points, which is determined after the guide wire passes and restores the forward blood flow. The TIMI thrombus score is determined as follows: 0 point: no thrombus is determined；1 point: blurred thrombus image is visible；2 point: clear thrombus image, but the length of the thrombus image is less than 1/2 vessel diameter；3 point: clear thrombus image, the length of the thrombus image is 1/2\

⁃ 2 times the vessel diameter；4 point: clear thrombus image, the thrombus image is more than 2 times the vessel diameter；5 points : complete occlusion of blood vessels)

⁃ 4：Emergency PCI revascularization was completed within 12 hours after the occurrence of myocardial infarction. Postoperative angiography confirmed that residual stenosis was less than 50%.

⁃ 5: Sign the informed consent form voluntarily