Background:Early reports indicate that cardiac involvement can commonly occur in COVID-19 patients. This prospective observational study aimed to evaluate myocardial dysfunction in critically ill COVID-19 patients. Methods:Forty adult patients with confirmed COVID-19 disease admitted to the intensive care unit of a tertiary care hospital were included, following which demographic, baseline laboratory and serial echocardiography was done on days 1, 3, 5 & 7 to assess global or regional wall motion abnormality, left ventricular function [ejection fraction (LVEF), E/e) and right ventricular function [tricuspid annular plane excursion (TAPSE), tricuspid regurgitation (TR) jet)]. Any new onset ECG changes were also noted. Results:Patients (n=40) had median (IQR) age of 51.5 (38.5- 63.5) and median (IQR) SOFA score of 5.5 (5- 7). Median (IQR) P/F ratio of the included patients at the time of recruitment was 250 (180- 300) and median (IQR) Charlsons comorbidity index was 2 (1- 4). Proportion (95% CI) of patients died during hospital stay was 15 (7.1- 29.1) %. We found that, on day 1, 25% patients had mild to moderate LV dysfunction. Although LVEF was statistically higher in patients receiving mechanical ventilation, LVEF, E/e, TAPSE and TR jet did not change significantly from base line till day 7, in both mechanically ventilated and nonventilated patients, or in survivors and non-survivors. However, LVEF correlated with PaO2/FiO2 ratio (P/F) ratio at day 3 (rho= 0.46, p=0.003), 5 (rho= 0.47, p=0.002) and 7 (rho= 0.41, p=0.01), whereas TR jet with correlated inversely wit P/F ratio at day 1 (rho= -0.39, p=0.01) and 3 (rho= -0.39, p=0.01). Conclusion: Our study highlights that although P/F ratio correlated with both left ventricular and right function, the dynamics of both left ventricular and right ventricular function was non- progressive in both mechanically ventilated and as well as spontaneously breathing patients, and similar in both survivors and non survivors.