Research Communications of the 24th ECVIM-CA Congress

No conflicts of interest reported. Canine idiopathic pulmonary fibrosis (CIPF) is a progressive interstitial lung disease usually diagnosed by thoracic CT-scan that mainly affects West Highland white terriers (WHWT). Pulmonary hypertension (PH), a severe co-morbid condition with a challenging diagnosis, may develop in CIPF dogs. The ratio between the right pulmonary vein and pulmonary artery (PV/ PA) has been described as an echocardiographic indicator of PH in CIPFdogs. This study was intended to investigate whether CT-scan angiography cardiac findings are 1) altered in dogs with cIPF compared to healthy control dogs and 2) correlated with PV/PA measured by echocardiography (PV/PA US ). Thoracic CTA images from 6 WHWT with CIPF (Group A) and 9 healthy controls from various breeds (Group B) were retrospectively reviewed by one observer. All measurements were obtained in transverse post-contrast images displayed in a soft tissue window. PV and PA were measured dorsal to the right atrium, perpendicular to the long axis of these vessels. In addition, pulmonary trunk (PT) was assessed just ventral to the division of pulmonary arteries, perpendicular to its long axis. Ascending aorta (Ao) was also measured perpendicular to its long axis. Transverse reformatted images were obtained to have a view equivalent to the standard 4 chambers-echocardiographic view where right ventricle (RV) and left ventricle (LV) were measured. Three ratios were calculated PV/PA CT , PT/Ao and RV/LV, compared between groups and correlated with PV/PA US in both bi-dimensional (BD) and M-modes (MM). Statistical analyses were performed with XLStat â software. Values are given as mean AE sd. Statistical significance was set at a P ≤ 0.05. PV/PA CT was lower in group A (0.64 AE 0.18) in comparison to group B (1.00 AE 0.23, P = 0.008) and correlated with PV/PA US (BD: r = 0.796, P = 0.001; MM: r = 0.730, P = 0.003). PT/Ao was higher in group A (1.18 AE 0.08) compared to group B (0.92 AE 0.14, P = 0.001) and correlated only with PV/PA US measured in BD mode (r = -0.623, P = 0.02). The RV/LV ratio was increased in group A (0.91 AE 0.11) in comparison to group B (0.70 AE 0.08, P = 0.001) and a correlation between RV/LV and PV/PA US was found (BD: r = -0.726, P = 0.005; MM: r = -0.657, P = 0.01). In conclusion, in WHWT with CIPF, PV/PA CT , PT/Ao and RV/LV ratios measured on thoracic CTA images are correlated with PV/PA US and may serve in the assessment of PH.