The prevalence of pulmonary hypertension assessed using the pulmonary vein‐to‐right pulmonary artery ratio and its association with survival in West Highland white terriers with canine idiopathic pulmonary fibrosis

Abstract

Background Pulmonary hypertension (PH) is a known co-morbidity in West Highland white terriers (WHWTs) affected with canine idiopathic pulmonary fibrosis (CIPF). The pulmonary vein-to-right pulmonary artery ratio (PV/PA) has recently been described for the detection of pre-capillary PH in dogs. The objective of the present study was to estimate the prevalence of PH at diagnostic, in WHWTs affected with CIPF, by using PV/PA, in comparison with a group of healthy breed-matched controls (CTRLs). Additional study objective was to explore whether the presence of PH at initial diagnosis of CIPF impacted survival time in dogs treated with sildenafil. Results Twenty-five client-owned WHWTs presented with CIPF and 19 CTRLs were included in the study. PV/PA in either two-dimensional mode (2D) or time-motion mode or both were measured from cineloops in each dog. Dogs were classified according to PV/PA value into non/mild PH (PV/PA measured in 2D ≥ 0.7) or moderate/severe PH (PV/PA < 0.7). Survival data of WHWTs affected with CIPF were extracted from medical record to assess association between presence of PH at diagnosis and outcome. 60 % overall prevalence for moderate/severe PH was estimated in this cohort of WHWTs presented with CIPF vs. 5 % in CTRLS (P = 0.0002). The presence of moderate/severe PH at initial presentation was not associated with survival. Conclusions Results of the present study confirm a high prevalence of PH at diagnosis in WHWTs affected with CIPF and highlight the utility of PV/PA as a non-invasive surrogate for assessment of PH in this population.

Utility of Computed Tomographic Angiography for Pulmonary Hypertension Assessment in a Cohort of West Highland White Terriers With or Without Canine Idiopathic Pulmonary Fibrosis

“…In this study, 45% of WHWTs affected with CIPF had PH according to PV/PA measured on 2D-mode echocardiography. This proportion is in accordance with previously reported prevalence of 44% according to tricuspid regurgitation velocity in a cohort of 45 WHWT affected with CIPF ( 5 ) and of 60% according to PV/PA measured on 2D-mode echocardiography in a cohort of 25 CIPF WHWT ( 6 ). In human patients with interstitial lung disease, the presence of PH is associated with a worse prognosis ( 28 , 29 ).…”

“…This decision, taken before the ACVIM consensus statement was published, can be justified as follows. PV/PA is an echocardiographic parameter that has recently been described in veterinary medicine to evaluate the presence of PH ( 6 , 16 , 27 ). The normal value of this PV/PA has been defined to be ~1 ( 27 ).…”

“…A cutoff value of 0.7 for PV/PA measured on 2D-mode echocardiography was proven to diagnose dogs with moderate to severe precapillary PH with a good sensitivity (96%) and specificity (82%) ( 16 ). Moreover, a recent study highlighted the usefulness of PV/PA measured with 2D-mode echocardiography as a non-invasive method to diagnose PH in a population of WHWTs with or without PH ( 6 ).…”

“…Post-contrast images were acquired directly after manual injection of 2 ml/kg of iodinated contrast medium (iohexol 5 or iopromide 6 ).…”

“…One of the main complications of CIPF is the development of precapillary pulmonary hypertension (PH) with a percentage of affected dogs varying between 40 and 60% ( 2 , 3 , 5 , 6 ). PH is defined as an abnormally increased pulmonary arterial pressure, >46 mmHg for systolic pressure ( 7 , 8 ).…”