Objective: To study incident and clinical characteristics of the coronary microcirculation dysfunction (CMD) in patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI) by myocardial contrast echocardiography (MCE) and to explore the predictive value of CMD for in-hospital acute heart failure event. Methods: One hundred and forty five patients with AMI who had received PCI and completed MCE during hospitalization in Peking University People' s Hospital from November 2015 to July 2021 were enrolled in our study. The patients were divided into CMD group and normal group according to the coronary microcirculation status detected by MCE. Clinical data and MCE data of the two groups were collected and analyzed. The acute heart failure event during hospitalization was described. A multivariate Logistic regression model was built to analyze the risk of acute heart failure in patients with CMD. A receiver operating characteristic (ROC) curve was drawn to evaluate the value of CMD in predicting acute heart failure event. Results: CMD detected by MCE occurred in 87 patients (60%). Compared with normal group, patients with CMD had higher troponin I (TnI) peak level [52.8 (8.1, 84.0) μg/L vs. 18.9 (5.7, 56.1) μg/L, P=0.005], poorer Killip grade on admission (P=0.030), different culprit vessel (P < 0.001) and more patients had thrombolysis in myocardial infarction (TIMI) flow pre-PCI less than grade 3 in culprit vessel (65.1% vs. 43.1%, P=0.025). Meanwhile, patients with CMD had poorer left ventricular ejection fraction (LVEF) [52% (43%, 58%) vs. 61% (54%, 66%)], poorer global longitudinal strain (GLS) [-11.2% (-8.7%, -14.0%) vs.-13.9% (-10.8%, -17.0%)] and worse wall motion score index (WMSI) (1.58±0.36 vs. 1.25± 0.24) (P all < 0.001). Acute left heart failure happened in 13.8% of the CMD patients, which were significant higher than that in the patients with normal coronary microcirculation perfusion (1.7%, P=0.013). After correcting for the culprit vessel, the TIMI flow pre-PCI in the culprit vessel and the peak TnI value, the risk of acute left heart failure in the patients with CMD was still high (OR=9.120, 95%CI: 1.152-72.192, P=0.036). The area under ROC curve (AUC) was 0.677 (95%CI: 0.551-0.804, P=0.035). Conclusion: The incidence of CMD detected by MCE in patients with AMI post-PCI was 60%. Patients with CMD have a higher risk of acute left heart failure during hospitalization.