Pulmonic stenosis in dogs: survival and risk factors in a retrospective cohort of patients.

Abstract

OBJECTIVES: To assess survival and risk factors in dogs with pulmonic stenosis. METHODS: A retrospective review of medical case records of all cases of pulmonic stenosis >50 mmHg, undergoing pulmonary balloon valvuloplasty or not. Survival curves and multivariate analysis were calculated in the overall population and in subgroups. RESULTS: One hundred and seventy-two cases were included. Factors negatively affecting survival were clinical signs [hazard ratio (HR) 3&#x2009;&#xb7;&#x2009;44, P&#x2009;<&#x2009;0&#x2009;&#xb7;&#x2009;001], younger age at diagnosis (HR 3&#x2009;&#xb7;&#x2009;96, P&#x2009;=&#x2009;0&#x2009;&#xb7;&#x2009;001) and valve morphology type B (HR 3&#x2009;&#xb7;&#x2009;33, P&#x2009;=&#x2009;0&#x2009;&#xb7;&#x2009;001) in the overall population. In those that had pulmonary balloon valvuloplasty group only clinical signs was significant (HR 3&#x2009;&#xb7;&#x2009;44, P&#x2009;<&#x2009;0&#x2009;&#xb7;&#x2009;001). In cases that did not undergo pulmonary balloon valvuloplasty group Doppler gradient (HR 1&#x2009;&#xb7;&#x2009;02, P&#x2009;<&#x2009;0&#x2009;&#xb7;&#x2009;001), clinical signs (HR 5&#x2009;&#xb7;&#x2009;41, P&#x2009;=&#x2009;0&#x2009;&#xb7;&#x2009;002), valve morphology type B (HR 10&#x2009;&#xb7;&#x2009;20, P&#x2009;=&#x2009;0&#x2009;&#xb7;&#x2009;001) and younger age at diagnosis (HR 12&#x2009;&#xb7;&#x2009;82, P&#x2009;<&#x2009;0&#x2009;&#xb7;&#x2009;001) negatively affected survival. Dogs with severe pulmonic stenosis undergoing pulmonary balloon valvuloplasty (HR 0&#x2009;&#xb7;&#x2009;47, P&#x2009;=&#x2009;0&#x2009;&#xb7;&#x2009;047) and asymptomatic dogs with moderate pulmonic stenosis (HR 0&#x2009;&#xb7;&#x2009;10, P&#x2009;=&#x2009;0&#x2009;&#xb7;&#x2009;042) had a better outcome. Younger age at diagnosis was correlated with poorer outcome in right-sided congestive heart failure dogs (HR 14&#x2009;&#xb7;&#x2009;02, P&#x2009;=&#x2009;0&#x2009;&#xb7;&#x2009;01). CLINICAL SIGNIFICANCE: Clinical signs, valve morphology type B and age at diagnosis are risk factors in pulmonic stenosis patients. Pulmonary balloon valvuloplasty is a reasonable treatment choice in dogs with severe pulmonic stenosis.