Anne-Marie Koop

36 Pulmonary artery banding resulted in enhanced systolic function, while the occurrence of clinical symptoms is associated with worse diastolic function Pressure-volume analysis revealed hemodynamic distinctions between PAB- and PAB+CF (representative pressure-volume loops in figure 3a-c ). End systolic elastance (ameasure of contractility) showed a trend to be higher in PAB+CF ( figure 3e ). However, the performed stroke work in PAB+CF was significantly lower than in PAB- ( figure 3f ), reflecting decreased stroke volume despite enhanced end systolic elastance. Figure 3. Pressure-volume analysis. Representative pressure-volume loops of CON, PAB- and PAB+CF (A- C), end systolic pressure volume relations indicated by solid lines, end diastolic pressure volume relations indicated by dashed lines. Indices of diastolic function; end diastolic elastance (C) and end diastolic pressure (D). The single-beat method was used to determine elastance in all groups because of the fatality of the procedure in the majority of animals in the PAB+CF group. However, in many animals (all in the CON- and PAB groups and some in the PAB+CF group) we were able to perform vena cava occlusion without problems. In this figure data during vena cave occlusion are shown to illustrate the hemodynamic changes in the different groups. End systolic elastance (E) and stroke work (F). Mean±SEM. Arrows indicate p<0.05 between respective groups. Eed= end diastolic elastance, Ped= end diastolic pressure, Ees = end systolic pressure Advanced diastolic dysfunction hallmarked PAB+CF compared to PAB-: both end diastolic elastance ( figure 3c , p=0.06) and end diastolic pressure ( figure 3d ) were higher in PAB+CF. This was due to increased stiffness rather than to incomplete active relaxation as tau did not differ between PAB- and PAB+CF ( table 1 ). Clinical right ventricular failure in pressure overload is characterized by enhanced systolic function and diastolic dysfunction.