Canine pulmonary vein-to-pulmonary artery ratio: echocardiographic technique and reference intervals

F Birettoni; D Caivano; V Patata; N S Moïse; C Guglielmini; M Rishniw; F Porciello

doi:10.1016/j.jvc.2016.07.004

Canine pulmonary vein-to-pulmonary artery ratio: echocardiographic technique and reference intervals

J Vet Cardiol. 2016 Dec;18(4):326-335. doi: 10.1016/j.jvc.2016.07.004. Epub 2016 Sep 23.

Authors

F Birettoni¹, D Caivano¹, V Patata¹, N S Moïse², C Guglielmini³, M Rishniw⁴, F Porciello⁵

Affiliations

¹ Department of Veterinary Medicine, University of Perugia, Perugia, Italy.
² Department of Clinical Science, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
³ Department of Animal Medicine, Production and Health, University of Padua, Padua, Italy.
⁴ Veterinary Information Network, Davis, CA, USA.
⁵ Department of Veterinary Medicine, University of Perugia, Perugia, Italy. Electronic address: francesco.porciello@unipg.it.

PMID: 27670068
DOI: 10.1016/j.jvc.2016.07.004

Abstract

Objectives: The size of the pulmonary veins (PVs) and pulmonary arteries (PAs) changes in response to hemodynamic alterations caused by physiological events and disease. We sought to create standardized echocardiographic methods for imaging the right ostium of the pulmonary veins (RPVs) and the right pulmonary artery (RPA) using specific landmarks and timing to quantify vessel diameters and phasic changes during the cardiac cycle.

Animals: Fifty client-owned healthy dogs prospectively recruited.

Methods: M-mode and 2-dimensional images were obtained from modified right parasternal long and short axis views. Right ostium of the pulmonary veins and RPA measurements were timed with electrical [peak of the QRS complex (RPV_QRS and RPA_QRS) and end of T wave (RPV_T and RPA_T)] or mechanical events [RPV and RPA vessels at their respective maximal (RPV_MAX; RPA_MAX) and minimal (RPV_MIN; RPA_MIN) diameters]. Right ostium of the pulmonary veins and RPA measurements were also indexed to the aorta.

Results: In normal dogs regardless of the echocardiographic view or time in the cardiac cycle, the RPV/RPA ratio approximated 1.0. Mechanically timed fractional changes (distensibility indices) in RPV and RPA diameters did not differ (p=0.99; 36.9% and 36.8%, respectively). ECG-timed fractional changes (distensibility indices) in RPV and RPA diameter were at least 50% smaller than mechanically timed changes (p<0.05). RPV:Ao and RPA:Ao ranged between 0.3 and 0.6, with lower values obtained in diastole and larger values in systole (p<0.0001). Multiple positive and negative deflections were identified on the RPV and RPA M-mode tracings.

Conclusion: This study provides detailed methodology and 2D and M-mode reference intervals for the RPV and RPA dimensions and the phasic changes during the cardiac cycle of the dog using echocardiography.

Keywords: Healthy dog; Index; Pulmonary artery distensibility index; Pulmonary vein distensibility index.

MeSH terms

Animals
Dogs / anatomy & histology*
Echocardiography / methods
Echocardiography / veterinary*
Female
Male
Prospective Studies
Pulmonary Artery / anatomy & histology*
Pulmonary Veins / anatomy & histology*
Reference Values