Feasibility in the echocardiographic estimation of parameters of the right ventricle in prone position

Background: Echocardiographic cardiac parameters in the prone position are usually obtained with an esophageal probe. The feasibility of obtaining them by means of a transthoracic approach is unknown. Objective: Estimating the feasibility to obtain parameters of the right ventricle by transthoracic echocardiography in prone position on the subject. Methods: Pilot design of consecutive case series without cardiopulmonary disease. Demographic. vital signs and echocardiographic variables were defined in the ventral initial, prone and ventral final decubitus positions. The data are shown with averages and standard deviations, and frequencies and percentages according to the variable. The differences between the positions were calculated with ANOVA of repeated samples and adjustment of Bonferroni test. lntra-subject variability was obtained by the Bland-Altman procedure and its 95% confidence interval. Results: We studied 50 subjects, 44 (88%) males, age 30 +/- 6 years and body mass index 25.65 +/- 2.71 kg/m(2). Tricuspid annular plane systolic excursion (TAPSE) and S'-wave were measured 100% of the time. The vital signs and echocardiographic variables according to the position had differences in: heart rate (74 +/- 9 vs. 77 +/- 9 vs. 75 +/- 8 beats/min), partial oxygen saturation (94.40 +/- 1.70 vs. 96.64 +/- 1.79 vs. 95.32 +/- 1.36%) and mean systemic blood pressure (65.33 +/- 5.38 vs. 67.69 +/- 6.31 vs. 65.29 +/- 5.62 mmHg); TAPSE (19.74 +/- 3.24 vs. 21.60 +/- 2.97 vs. 19.44 +/- 2.84 mm), mean difference (bias) 0 (2, -2.0) and S'-wave (13.52 +/- 1.87 vs. 15.02 +/- 2.09 vs. 13.46 +/- 1.55 cm/s), mean difference (bias) -0.46 (1.21, -2.14) respectively. Conclusions: Obtaining right ventricle parameters by transthoracic ecocardiopraphy is feasible in the prone position.