This is a prospective observational study of consecutive patients presenting with STEMI to the Prince of Wales Hospital over a 12-month period. All patients will receive standard of care including reperfusion and GDMT irrespective of study enrolment. Patient will be followed for 9 months after enrolled in this study. Point-of-care ultrasound (POCUS) using a hand-held ultrasound (Vscan, GE Healthcare) will be performed to assess baseline LVEF within 48 hours of admission. Patients with baseline moderate-to-severe LV dysfunction by visual POCUS assessment (i.e. LVEF <40%) will be recruited for follow-up LVEF assessment at 3 months. Patients with persistent LVEF <40% by POCUS will undergo formal echocardiography to confirm LVEF by either 2D area (Simpson's rule) and 3D volumetric measurements. In 9 month visit, patient's clinical data will be collected and no echo is needed during this visit.

This is a prospective observational study of consecutive patients presenting with STEMI to the Prince of Wales Hospital over a 12-month period. All patients will receive standard of care including reperfusion and GDMT irrespective of study enrolment. Patient will be followed for 9 months after enrolled in this study. Point-of-care ultrasound (POCUS) using a hand-held ultrasound (Vscan, GE Healthcare) will be performed to assess baseline LVEF within 48 hours of admission. Patients with baseline moderate-to-severe LV dysfunction by visual POCUS assessment (i.e. LVEF <40%) will be recruited for follow-up LVEF assessment at 3 months. Patients with persistent LVEF <40% by POCUS will undergo formal echocardiography to confirm LVEF by either 2D area (Simpson's rule) and 3D volumetric measurements. In 9 month visit, patient's clinical data will be collected and no echo is needed during this visit.

Categorical variables were presented in frequency tables and were compared using the Pearson Chi square test if all cell sizes were more than 5, or Fisher exact test if otherwise. Parametric and nonparametric continuous variables were expressed as mean ± SD and median (interquartile range) and were compared using the Student t test and Mann-Whitney U test, respectively. P<0.05 was considered statistically significant. All statistical analyses were performed using SPSS version 24.0

Inclusion Criteria:

1. > 18 years of age
2. STEMI (defined by symptoms of myocardial ischemia accompanied by persistent elevation of the ST segment on ECG and the subsequent rise of biomarkers of myocardial necrosis)
3. Ability to provide informed consent and to complete the study and required follow-up

Exclusion Criteria:

1. Pregnancy
2. Pre-existing ICD or CRT-D implantation

The medical records of patients who have STEMI will be reviewed to determine preliminary eligibility according to patient inclusion/exclusion criteria. After a patient signs an informed consent for this study, he/she is considered enrolled in the study. An informed consent including privacy authorization must be obtained prior to the enrollment. The signed Patient Informed Consent should be kept with the study documentation and must be available for monitoring.