BACKGROUNDIncreasing attention has been paid to cardiac involvement in patients with coronavirus disease 2019 (COVID-19). Yet, scarce information is available regarding the morphological and functional features of cardiac impairments in these patients. METHODSWe conducted a prospective and serial echocardiographic study to investigate the structural and functional cardiac changes among COVID-19 patients admitted to the intensive care unit (ICU). From January 21 to April 8, 2020, a total of 51 ICU patients (31 critically ill and 20 severely ill) with confirmed COVID-19 were monitored by serial transthoracic echocardiography examinations. Outcomes were followed up until April 8, 2020. RESULTSOf 51 ICU patients, 33 (64.7%) had cardiovascular comorbidities. Elevations of levels of cardiac biomarkers including high-sensitivity cardiac troponin-I (hs-cTnI) and brain natriuretic peptide were observed in 62.7% and 86.3% of patients, respectively. Forty-two (82.3%) had at least one left-heart and/or right-heart echocardiographic abnormality. The overall median left ventricular ejection fraction (LVEF) was 65.0% (IQR 58.0-69.0%), with most (44/86.3%) having preserved LVEF. Sixteen patients (31.4%) had increased pulmonary artery systolic pressure, and 14 (27.5%) had right-ventricle (RV) enlargement. During the study period, 12 (23.5%) patients died. LVEF was comparable between survivors and non-survivors, while non-survivors had more often pulmonary hypertension (58.3% vs. 23.1%; P=0.028) and RV enlargement (58.3% vs. 17.9%, P=0.011). Kaplan-Meier analysis demonstrated similar survival curves between patients with vs. without echocardiographic left-heart abnormalities (P=0.450 by log-rank test), while right-heart abnormalities had adverse impact on mortality (P=0.012 by log-rank test). CONCLUSIONSTypical cardiac abnormality in ICU patients with COVID-19 was right-heart dysfunction with preserved LVEF. Echocardiographic right-heart dysfunction was associated with disease severity and increased mortality in patients affected by COVID-19. CLINICAL TRIAL REGISTRATIONUnique identifier NCT04352842.