Clinical efficacy of sildenafil in treatment of pulmonary arterial hypertension in dogs.
BACKGROUND
Pulmonary arterial hypertension (PAH) in dogs carries a poor prognosis. Sildenafil increases exercise capacity and improves hemodynamics in people with PAH.


OBJECTIVE
Dogs receiving sildenafil will have lower pulmonary arterial pressure, increased exercise capacity, and better quality of life (QOL) than dogs receiving placebo.


METHODS
Thirteen dogs with echocardiographic evidence of PAH.


METHODS
Prospective short-term, randomized, placebo controlled, double-blind, crossover study. Dogs with PAH were randomly allocated to receive sildenafil or placebo for 4 weeks, followed by the alternative treatment for 4 weeks.


RESULTS
Dogs receiving sildenafil had a significantly lower estimated pulmonary arterial pressure (median, 56 mmHg; range, 34-83 mmHg) than at baseline (median, 72 mmHg; range, 61-86 mmHg; P=.018), but not significantly lower than those receiving placebo (median, 62 mmHg; range, 49-197 mmHg). Exercise capacity was significantly greater in dogs receiving sildenafil than those receiving placebo (mean activity count per minute: 101+/-47 versus 74+/-32; P=.05). QOL scores were significantly higher in dogs receiving sildenafil than dogs receiving placebo.


CONCLUSIONS
Sildenafil decreases systolic pulmonary arterial pressure from baseline in dogs with PAH and is associated with increased exercise capacity and QOL when compared to treatment with placebo.
Brown
A J
AJ
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA. andrewjb@msu.edu
Davison
E
E
Sleeper
M M
MM
D000818:Animals; D018592:Cross-Over Studies; D004285:Dogs; D004311:Double-Blind Method; D005260:Female; D006976:Hypertension, Pulmonary / Q000188:drug therapy / Q000662:veterinary*; D008297:Male; D010879:Piperazines / Q000627:therapeutic use*; D011687:Purines / Q000627:therapeutic use; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000627:therapeutic use*; D014665:Vasodilator Agents / Q000627:therapeutic use*
D010879:Piperazines; D011687:Purines; D013450:Sulfones; D014665:Vasodilator Agents; D000068677:Sildenafil Citrate