Background and Goal of Study: 
Fluid infusion to optimize cardiac output (CO) is a challenge during
cardiac surgery (CS). There are no accurate indices to determine fluid responsiveness in this setting (1). No study has examined the accuracy of intra-operative right ventricular longitudinal strain (RVLS) (2, 3) in determining preload dependence during a fluid challenge (FC). We hypothesized that changes in RVLS
could predict preload dependence during a FC in CS patients.
Materials and Methods: 
We conducted an observational, prospective study in CS patients. Measurements
were conducted using TEE after general anesthesia and before sternotomy (GE Vivid S7). We recorded LVEF, RV indices (pulsed tissue Doppler S rate (S’), PASP, RV isovolumic acceleration (IVA)) and TVI. Measures were performed before and after a 250ml FC. Responders (RESP) were defined as an increase
of 10% of TVI. RESP and nonresponders (NRESP) were compared by Student-t and Chi² tests (p<0.05 significant).
Results and Discussion: 
37 patients (M/F:28/9) were included. Mean age was 66 +/-9.6 years old. Mean
LVEF was 61.6%. 26 patients (74,3%) were NRESP. Mean RVLS values were: -18.12 +/-2.31% (CI95 [-20.05; -16.19]) in RESP vs -18.5 +/- 4.92% [CI95 -20.58; -16.42] in NRESP before FC (p=0.38), and of -16.37 +/- 4.9% (CI95 [-12.26; -20.48]) in RESP vs -17.7 +/- 4.02% (CI95 [-16; -19]) in NRESP after FC
(p=0.22) (fig 1). There were no differences in S’ values in RESP (8.47, CI95 [6.98; 9.97]) vs NRESP (8.05, CI95 [7.18; 8.93], p=0.29). There was a significant difference in IVA values in RESP (2.68 CI95 [2.1; 3.27]) vs NRESP (3.45, CI95 [2.69; 4.21], p=0.04).
This study is the first to examine strain values as a dynamic index using a FC. Increasing preload using a 250ml FC did not modify RVLS in cardiac surgery patients under general anesthesia and mechanical ventilation. However, we observed a non-significant increase (deterioration) of RVLS in NRESP (Fig 1).
Conclusion: 
Considering the limits of this study, RVLS cannot be used as a dynamic index of fluid
responsiveness.
References:
1. Clin Physiol Funct Imaging.2017
2. Anesth Analg.2017;125(5):1475–8
3. Anesth Analg.2014;118(3):525–44

09 / Right ventricular strain as a predictor of vascular filling responsiveness in cardiac surgery