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

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) 3·44, P<0·001], younger age at diagnosis (HR 3·96, P=0·001) and valve morphology type B (HR 3·33, P=0·001) in the overall population. In those that had pulmonary balloon valvuloplasty group only clinical signs was significant (HR 3·44, P<0·001). In cases that did not undergo pulmonary balloon valvuloplasty group Doppler gradient (HR 1·02, P<0·001), clinical signs (HR 5·41, P=0·002), valve morphology type B (HR 10·20, P=0·001) and younger age at diagnosis (HR 12·82, P<0·001) negatively affected survival. Dogs with severe pulmonic stenosis undergoing pulmonary balloon valvuloplasty (HR 0·47, P=0·047) and asymptomatic dogs with moderate pulmonic stenosis (HR 0·10, P=0·042) had a better outcome. Younger age at diagnosis was correlated with poorer outcome in right-sided congestive heart failure dogs (HR 14·02, P=0·01). 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.