Echocardiographic Assessment of the Pulmonary Vein to Pulmonary Artery Ratio in Canine Heartworm Disease

• Published in: Animals (Basel) Vol. 13; no. 4; p. 703
• Main Authors: Matos, Jorge Isidoro, Caro-Vadillo, Alicia, Falcón-Cordón, Yaiza, García-Rodríguez, Sara Nieves, Costa-Rodríguez, Noelia, Carretón, Elena, Montoya-Alonso, José Alberto
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 17.02.2023; MDPI
• Subjects: Analysis; Animals; Aorta; Diagnostic systems; Dirofilaria immitis; Disease; Disease transmission; Dogs; Dyspnea; Echocardiography; Endarteritis; Heart diseases; Heart failure; heartworm disease; Hypertension; Lung diseases; Parasites; Pulmonary arteries; Pulmonary artery; Pulmonary hypertension; Pulmonary lesions; pulmonary vein; PV:PA ratio; Regurgitation; RPAD index; Thromboembolism; Variables; Veins; Veins & arteries; Spain; United States > US; RPAD index; pulmonary artery; pulmonary hypertension; PV:PA ratio; pulmonary vein; heartworm disease; animal diseases; Dirofilaria immitis
• ISSN: 2076-2615; 2076-2615
• DOI: 10.3390/ani13040703

produces proliferative pulmonary endarteritis and pulmonary thromboembolism in infected dogs. The pulmonary vascular lesions lead to irreversible and persistent structural damage and, as a consequence, sustained precapillary pulmonary hypertension (PH). The purpose of this study was to assess the diagnostic value of the pulmonary vein to pulmonary artery ratio (PV:PA ratio) to determine moderate or severe PH (>50 mmHg) in dogs with heartworm disease. A total of 151 naturally heartworm-infected and 66 healthy dogs were included in the study. The presence/absence of PH was based on the right pulmonary artery distensibility index (RPAD index < 29.5%), and the PV:PA ratio was echocardiographically measured by the time-motion mode (M mode) and two-dimensional mode (2D mode). Other echocardiographic parameters were also assessed (pulmonary trunk to aorta ratio, tricuspid regurgitation pressure gradient, and AT:ET ratio). The results of the PV:PA ratio showed a highly positive correlation between the M and 2D modes (r = 0.928). The PV:PA ratio obtained by the M mode was identified as the strongest predictor for RPAD index (R 0.628, < 0.0001) with a good diagnostic accuracy (AUC = 0.99). The results of PV/PA by the 2D mode showed a similar prediction for the RPAD index (R 0.606, < 0.0001) with a good diagnostic accuracy (AUC = 0.98). Both of the 2D and M modes' PV:PA ratios decreased significantly with the presence of PH. A cut-off value of ≤0.845 showed high sensitivity and specificity for the M mode (97% and 94%, respectively) and the 2D mode (96% and 93%, respectively). The PV:PA ratio may be useful as a complementary diagnostic method for the estimation of moderate or severe PH in dogs with heartworm.