Anne-Marie Koop

34 Ratswithorwithout clinical signs of failure showeddistinct functional, morphological and pathological profiles All rats with PAB showed functional and morphological RV-abnormalities, but these were significantly more pronounced in PAB+CF than in PAB-. At termination, PAB+CF rats had a lower cardiac index (both when cardiac output was indexed for bodyweight or tibialength) ( figure 2a ), RV stroke volume ( table 1 ) and TAPSE ( figure 2b ). Furthermore, PAB+CF rats had a more enlarged right atrium ( figure 2c ) and pericardial effusion (3/5 of PAB+CF vs. 0/4 of PAB- rats; figure 2d ). In PAB+CF, the right atrium was also more hypertrophic ( figure 2e ) and the liver wet/dry-weight ratio was increased signifying congestion ( figure 2f ). In line with this, postmortem examination revealed macroscopic liver congestion (so-called ‘nutmeg liver’) and ascites in PAB+CF, but not in PAB- (representative images in figure 2g ). Figure 2. Echocardiographic and pathological confirmation of clinical RVF. PAB+CF was distinct from PAB- with regard to cardiac index (A), TAPSE (B), RA diameter (C), presence of pericardial effusion (example echo- image in D), RA weight (E) and liver wet-to-dry ratio (F). Representative images of liver congestion (left- hand panel in G) and ascites (right-hand panel in G). Mean±SEM. Arrows indicate p<0.05 between respective groups. TAPSE= tricuspid annular plane systolic excursion, RA= right atrium, TV= tricuspid valve.