Inferior vena cava dilation predicts global cardiac dysfunction in acute respiratory distress syndrome: A strain echocardiographic study.

PURPOSE

Limited data exist on the utility of ultrasonographic evaluation of inferior vena cava (IVC) in acute respiratory distress syndrome (ARDS). We studied the value of IVC diameter in assessing cardio-circulatory performance in ARDS using strain echocardiography.

MATERIALS AND METHODS

Retrospective cross-sectional analysis of Doppler echocardiograms of patients with moderate-severe ARDS was performed. Right ventricle (RV) parameters, IVC diameter, and left ventricle (LV) systolic and diastolic parameters were collected. RV free wall strain (RVFWS) and LV global longitudinal strain (LVGLS) were calculated.

RESULTS

Fifty-one patients were dichotomized into two groups: with IVC > 2.1 cm (dilated) and with IVC ≤ 2.1 cm (nondilated). The dilated IVC group presented worse hypoxemic profile, hypotension, and poor perfusion markers. No significant associations with positive end-expiratory pressure or lung mechanics were observed. Dilated IVC was associated with impaired RV function, high central venous pressure, elevated pulmonary artery pressure, and LV systolic and diastolic dysfunctions. Strongest predictors of a dilated IVC were RVFWS, LVGLS, and tissue Doppler mitral annular early diastolic velocity. Dilated IVC predicted a global cardiac dysfunction defined by strain echocardiography (GCDS) with high sensitivity and specificity.

CONCLUSIONS

In ARDS, strain echocardiography analyses demonstrated that a dilated IVC is associated with GCDS and impaired hemodynamics independent of lung mechanics. A dilated IVC should be considered a marker of circulatory distress, signaling the potential necessity for improved hemodynamic optimization.