A British Labrador is the first dog in the world to undergo groundbreaking open heart surgery to cure a life threatening condition at the Royal Veterinary College's in Hertfordshire.
Three-year-old Mabel, from Melton in Leicestershire, suffered from congenital tricuspid dysplasia, meaning key valves in her heart were effectively fused together.
The condition meant her ventricles had just two very small holes for her blood to flow through, leading to Mabel suffering from extreme exhaustion and heart failure.
She was referred to cardiology specialists at the Queen Mother Hospital for Animals in Hatfield.
Initial examinations included cardiac ultrasound using a state-of-the-art ultrasound scanner.
Professor Dan Brockman performed the six-hour operation, helped by a large team of specialists including a perfusionist, three anaesthetists and two nurses.
The lifesaving surgery on February 15 was a world-first using cutting-edge technology to reverse Mabel's heart failure.
The procedure involved surgeons draining blood out of the main veins of Mabel's body before it entered the heart and then returned to a major artery once it had been oxygenated by the heart lung machine.
Vets then injected a solution with a high potassium content into the arteries that go to the muscle of the heart.
The fluid, which stops the heart beating and metabolic activity of the heart muscles, allowed vets to open the heart and inspect the structures inside.
Because the tricuspid valve was fused in the middle, vets sliced it open to free it from the fused ventricle before stitching it back together.
As a result, the newly stitched up valve was wide enough to allow the blood to flow through more easily.
The operation was deemed a complete success and Mabel returned to her home to Melton, after spending a six days in intensive care recovering.
Relieved owner Annabelle Meek, 69, said:
Prof Brockman carried out the first open-heart surgery at the RVC in 2005 and has worked alongside human cardiac surgeons and other veterinarians to develop his expertise.