Objectives the echocardiographic indices have not been validated in critically ill population. We investigated the correlation between some echocardiographic and hemodynamics parameters. Design Prospective Spontaneous non-interventional observational study. Setting Adult cardiothoracic intensive care unit, single center (Royal Brompton Hospital, London UK). Participants Consecutive adult patients admitted to cardiothoracic intensive care unit for severe respiratory failure, primary cardio-circulatory failure and post-aortic surgery. Interventions Clinical, hemodynamic parameters (stroke volume – SV, cardiac output – CO, mean arterial pressure – MAP, and cardiac power index – CPI) and echocardiographic indices of ventricular function (left ventricular total isovolumic time – t-IVT, mitral annular plane systolic excursion – MAPSE, and left ventricular fraction – LVEF) were evaluated offline. Measurements and main results 117 patients were studied (age 57.2 ± 19; 60.6% male). t-IVT showed an inverse correlation with SV, CO, MAP and CPI (respectively r: -67%; -38%; -45%; -51%). MAPSE exhibited a positive correlation with SV, CO, MAP and CPI (respectively r: 43%; 44%; 34%; 31%). LVEF did not show any correlation. In the multivariate analysis the association of t-IVT and hemodynamics was confirmed for SV, CO, MAP and CPI with the highest partial correlation between t-IVT and MAP (R = -58%). Conclusions MAPSE and t-IVT are two reproducible and reliable echocardiographic indices of systolic function and ventricular efficacy associated with hemodynamic variables in cardiothoracic critically ill patients, while LVEF did not show any correlation.