The additional value of strain imaging to detect right ventricular dysfunction in critically ill patients : A sub-study of the Simple Intensive Care Studies-I

INTRODUCTION. Right ventricular (RV) dysfunction is common in the critically ill and associated with adverse clinical outcomes. Critical care ultrasonography (CCUS) evaluates RV function with conventional measurements such as Tricuspid Annular Plane Systolic Excursion (TAPSE) and peak systolic tissue velocity at the tricuspid annulus (RV s'). Myocardial deformation imaging is a relative new technique to assess regional systolic function and is expressed in strain. Several studies suggest that strain imaging has an additional diagnostic and prognostic value compared to CCUS. In patients with heart failure and pulmonary hypertension, RV strain detected RV dysfunction when conventional CCUS measurements were preserved. However, the diagnostic value of RV strain has never been evaluated in a large unselected population of critically ill patients. OBJECTIVES. The objective of this study was to investigate the association between TDI-derived RV strain and conventional CCUS measurements to evaluate RV function in an unselected population of critically ill patients. METHODS. This sub-study was part of the Simple Intensive Care Studies-I (SICS-I: NCT02912624; Hiemstra et al. BMJ open 2017). This prospective cohort study included all consecutive adults who were acutely admitted with an intensive care unit (ICU) stay expected to last beyond 24 hours. Patients with atrial arrhythmias were excluded. Within 24 hours after admission transtho-racic ultrasonography was preformed, recording TAPSE, RV 's and color tissue Doppler images of the RV free wall and septum in the AP4CH view. Offline strain analysis was preformed to calculate global longitudinal RV peak strain (GLPS) and RV free wall longitudinal peak strain (RVLPS). TAPSE -17% and RVLPS >-20% were considered as reduced RV function. RESULTS. From March 2017 until July 2017, 238 patients were included in the SICS-I of which 51 patients were included in this sub-study. Baseline characteristics are displayed in table 1 in the appendix. Moderate correlations were found between TAPSE & GLPS (r=-0,65, p=0.00) and TAPSE & RVLPS (r=-0.58, p=0.00). The same applies for RV s' & GLPS (r=-0.57, p=0.00) and RV s' & RVLPS (r=-0.56, p=0.00). GLPS and RVLPS detected RV dysfunction in 8 out of 32 patients with normal TAPSE and/or RV s'. When examining the profile of these patients, a common feature was myocar-dial ischemia. CONCLUSIONS. This pilot study provides additional arguments for the application of strain imaging in the critically ill. RV strain seems to have an added value for detecting RV dysfunction when conventional measurements of RV function are preserved, especially in patients with underlying cardiac pathologies. ACKNOWLEDGEMENT Currently more patients are analyzed to elucidate and refine the outcomes of this study. In case of admission, enhanced results will be presented. [Table Presented].