Canine Heart Disease Detection and Treatment Advances: Breath Test and M-TEER Procedure

New research is advancing the detection and treatment of heart disease in dogs, with a breath test showing promise for earlier diagnosis and a minimally invasive procedure being adapted from human medicine.

Christopher Stauthammer, professor of cardiology at the University of Minnesota College of Veterinary Medicine, is developing a bedside breath analyzer to detect heart disease in dogs before it reaches a crisis point. The device uses a specialized interface resembling small airplane oxygen masks to capture exhaled air, and high-tech biosensors analyze volatile organic compounds—metabolic byproducts that travel from the blood into the lungs. By measuring these breath signatures, the team can identify specific patterns that distinguish a healthy dog from one with underlying heart disease or active heart failure. Initial pilot projects successfully detected differences in the breath profiles of healthy dogs versus those with various stages of heart disease. The research is now moving into a new trial involving dogs arriving at emergency clinics in respiratory distress, with the ultimate goal of placing the analyzers in primary care veterinary practices. The long-term vision includes expanding the technology to cats and other companion animals.

Heart disease is often ranked as the second leading cause of mortality in dogs, and many dogs do not show symptoms until they are in the midst of a life-threatening emergency. By the time a dog is struggling to breathe, the disease has often progressed to congestive heart failure, requiring expensive ICU stays and intensive oxygen therapy. Detecting congestive heart failure is exceptionally challenging in a primary care clinic and is often missed.

Separately, researchers are adapting the mitral transcatheter edge-to-edge repair (M-TEER) procedure—a minimally invasive, non-surgical treatment for mitral regurgitation in humans—for use in dogs. Mitral regurgitation is the most prevalent valvular heart disease in humans and is also common among dogs, especially older and smaller breed dogs. In both species, the mitral valve fails to close tightly enough to keep blood from flowing back into the left atrium as the heart contracts, which can lead to heart failure if untreated.

In humans, M-TEER involves guiding a catheter up the femoral vein to the heart and clipping the valve leaflets together with a clamp at the location where the two mitral leaflets fail to form a tight seal. Patients are often discharged from the hospital the next day, with a recovery far less rigorous than open-heart surgery. For dogs, a similar result can be achieved through a small chest incision, with transesophageal echocardiography helping to guide the placement of the clips. A notable challenge is that a dog's veins are much smaller than a human's, so the same tools are not feasible.

Interventional cardiologist John Carroll, professor emeritus of cardiology at the University of Colorado Anschutz School of Medicine, has been working with researchers at the Colorado State University College of Veterinary Medicine and Biomedical Sciences for over a decade to adapt human health interventions to dogs. Veterinarian Chris Orton, a professor of clinical sciences at CSU, recently published a paper in the Journal of Veterinary Cardiology comparing the procedure in humans and dogs. The authors note a steep learning curve for the novel therapy, writing that centers achieving early competence must share their experiences with other centers and report outcomes. They emphasize an opportunity for collaboration rather than competition, with a shared goal that high-competency M-TEER will be available to any dog that needs it and any dog owner who desires a less-invasive interventional option.

Early results of using M-TEER in dogs hold promise, but the procedure is not yet widely available to most pet owners. Most dogs with mitral regurgitation currently live the remainder of their lives on medication with ongoing symptoms, including reduced exercise tolerance.