Vets perform risky three-hour surgery to save horse with rare heart condition

A rider has praised the skill of vets who performed potentially life-saving surgery on her horse’s extremely rare circulatory condition.

Five-year-old Hanoverian Luigi had been sent to Leahurst Equine Hospital at the University of Liverpool for investigation into a heart murmur when vets discovered three arteriovenous fistulas in his neck — abnormal connections between his carotid artery and jugular vein.

The vessels had become so enlarged that they were filling with blood and pressing on his throat when he put his head down, causing him to make a noise when breathing.

Reconstruction image showing the unusual blood vessels in brown.

Scan reconstruction showing the unusual blood vessels in brown.

“As far as we know, he was born with the problem but it was only when he got to five that it started to become an issue,” explained Luigi’s owner Eve Rice, who bought the chestnut gelding as an unbacked three-year-old.

“I had him vetted when I first got him and nothing came up, but I took him to Germany and had to get him re-vetted and it was at that point that we discovered he had developed a heart murmur.

“When he went to Leahurst, they noticed that every time he put his head down there was a strong pulse in his neck and the swelling there would enlarge. They hadn’t seen it before and it took quite a few tests and scans to reach a conclusion.”

A cross-section of the head at the level of one of the usual blood vessel connections.

Normally, blood is pumped into the arteries by the heart and then travels through a fine network of capillaries into the veins. A fistula creates a shortcut straight from an artery to a vein and as a result the heart has to work harder to pump blood, putting it at an increased risk of failure.

“We get referrals for heart murmurs commonly but this is very unusual case, I have never seen another one, and there is only one other published example in a horse,” said Leahurst vet Harry Carslake.

He explained that when Luigi was first diagnosed, it was initially decided just to monitor him but his condition worsened and he started to make a noise when working. It was then decided that risky surgery would be necessary.

“The essential thing for us was to establish where the connections were — you can see from the images that he had a large and convoluted network of blood vessels. We located them using a combination of CT, ultrasound and fluoroscopy (where a contrast agent is injected into the artery),” Harry explained.

“In his case we found three abnormal connections, one large one next to his larynx and two others deeper into his head, which we knew we wouldn’t be able to access, but it was the larger one that was causing most of the problem.”

The three-hour procedure to tie-off the vessels was performed by specialist surgeon Debra Archer and involved a team of other specialists from the hospital, including experts in cardiology and imaging.

Eve said concern over the strain the fistulas were putting on Luigi’s heart had prompted her to go ahead with surgery and that while she was nervous “as they were clear it could go wrong”, she trusted the Leahurst team.

“It was very stressful, I dragged my neighbour round to watch Disney films with me while he was in surgery to try and take my mind of it!” she said. “When I went to see him afterwards, I expected him to be low but he was normal Luigi — in everyone’s faces trying to get cuddles.”

Luigi at home.

Luigi at home.

His recovery was also “quicker than expected” and Eve enlisted the help of physio Karris Reeves to help build his strength back up, as well as remaining in touch with Harry to monitor his progress.

“We were focused on making sure the cardio was really good. He lost quite a lot of muscle especially on his hindquarters, so the physio gave us pole exercises in hand and we did a bit of long-reining,” Eve said. “We also had to keep an eye on the pulse in his neck and make sure it wasn’t stronger and that his breathing stayed the same.

“It’s amazing how he’s come back from it such but he’s such a character and so full of life — he has always been fit as a fiddle,” she added, also joking that “while his show name is Lifetime, I now like to call him lifetime of debt!”

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Eve, who bought the son of Londonderry with inheritance money from her grandparents, is now carrying on with training with the aim to compete him at dressage in future.

“He’s quite quirky but very talented and while I want to compete him, I don’t want to rush,” she said. “He really is my horse of a lifetime and I wanted to find a way of thanking the entire team at Leahurst for taking the risk and giving him a better chance at life.”

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