Figure 1.

Right Ventricular Morphology and Function in 6J Mice Upon Pulmonary Artery Banding

(A) Schematic illustration of experimental design. The pulmonary artery (PA) of mice was constricted to 450 μm (mild), 360 μm (moderate), or 300 μm (severe) using titanium clips. Right ventricular (RV) function and morphology were determined 2 weeks after pulmonary artery banding (PAB). (B) Representative 2-dimensional parasternal short-axis view of the constricted PA 3 days after PAB. Color Doppler visualizes blood flow, aortic valve (AV), pulmonic valve (PV), and proximal right ventricular outflow tract (pRVOT). (C) RV hypertrophy reflected by Fulton index (n = 10/8/9/10 mice) and diastolic right ventricular wall thickness (RVWT, d) (n = 13/8/9/10 mice) increased with increasing stenosis grade. (D) Representative M-mode images depicting assessment of RVWT, d and diastolic right ventricular inner diameter (RVID, d) of an untreated (Ctrl) and PAB-exposed mouse. (E) RVID, d and (F) right atrial (RA) area increased with stenosis grade of PAB (n = 13/8/9/10 mice). (G) Number of mice with paradoxical motion of interventricular septum was increased with increasing stenosis grade (n = 8/9/10 mice). (H) Representative 2-dimensional parasternal apical 4-chamber view of a control mouse and upon PAB with different stenosis grades. RA = right atrium. (I) Systolic RV function as revealed from tricuspid annular plane systolic excursion (TAPSE) was impaired with increasing stenosis degree (n = 13/8/9/10 mice). Statistical significance was calculated with 1-way analysis of variance followed by Bonferroni’s post hoc test for C and I, and with Kruskal-Wallis test followed by Dunn’s multicomparison test for E and F. ∗P < 0.05; ∗∗P < 0.01; ∗∗∗P < 0.001.