Introduction

Normal pulmonary artery (PA) flow pattern changes when increased pressure in the pulmonary vascular bed is present. These changes are characterized by reduction in acceleration time (AT), ejection time (ET) and AT/ET ratio (AT/ET) evaluated by echocardiography. Congestive heart failure (CHF) increases pulmonary vascular pressure either by increased pulmonary venous pressure or by pulmonary vascular vasoconstriction.

Objectives

To evaluate if AT, ET and AT/ET ratio of PA flow could help to differentiate CHF from non-CHF dogs with chronic mitral valve disease (CMVD).

Methods

Forty dogs were included in a prospective observational cross-section clinical study, equally distributed into groups, B2 and C, based on radiographic, echocardiographic evaluations and clinical signs, according to American College of Veterinary Internal Medicine Guidelines for CMVD.

Results

AT, ET and AT/ET ratio were shorter in CHF compared to non-CHF dogs. Analysis of ROC curve for CHF diagnosis showed areas under the curve of 0.83 for AT (p<0.0001), 0.83 for ET (p<0.0001) and 0.72 for AT/ET (p=0.0052). For the purpose of differential diagnosis, AT higher than 76.50 ms, ET higher than 180 ms and AT/ET ratio higher than 0.42 were able to exclude CHF dogs.

Conclusions

AT, ET and AT/ET are shorter in symptomatic dogs with CMVD, and AT, ET and AT/ET seem to be useful to exclude CHF dogs with CMVD when normal PA flow pattern is presented.