A new heart treatment for dogs could provide a lifeline for millions of pets around the world, say researchers.
The drug pimobendan delays the onset of heart failure linked to mitral valve disease (MVD), the most common heart complaint suffered by dogs.
New evidence published in the Journal of Veterinary Internal Medicine shows that giving the drug to high-risk dogs with enlarged hearts - a known warning sign of the condition - delays the onset of heart failure by an average of 15 months and prolongs life.
Professor Adrian Boswood, from the Royal Veterinary College, who led the study, said: "This is a major breakthrough in treatment and could extend the lives of dogs around the world.
"Up until now, vets and dog owners had no choice but to wait until their dog developed heart failure before they could receive effective treatment. This ground-breaking research and treatment offers a lifeline to millions of dogs, by delaying heart failure for up to 15 months."
The seven-year study involved 360 dogs from 11 countries.
MVD mostly affects small dog breeds including cavalier King Charles spaniels, dachshunds, miniature poodles and terriers.
Cavalier King Charles spaniels are about 20 times more vulnerable than average to the disease.
Broadcaster Gloria Hunniford, who owns two cavalier King Charles spaniels, Roxy, four, and eight-year-old Gemma, said: "Our beautiful dog Gemma was diagnosed with a heart condition after she collapsed earlier this year, but before that we saw no real signs that she might be unwell. Thankfully, she's doing well with the right medication."