(C35) Transcatheter Edge-to-Edge Mitral Valve Repair for Myxomatous MItral Valve Disease in Dogs Under 2.5kg

Abstract:

Background: Transcatheter Edge-to-Edge mitral valve repair (TEER) using v-clamp® is a hybrid surgery that installs a clamp on mitral valve as an intervention after thoracotomy to Myxomatous Mitral Valve Disease (MMVD) patient. The existing standard for a patient's weight for TEER is 4kg, and it is known that risk is very high or impossible for those under 2.8kg. However, it was figured out that TEER was possible in patients under 2.5 kg.

Objectives: To report TEER surgery in small patients under 2.5kg Animal: 3 dogs with MMVD stage B2~D, had TEER surgery.


Methods:   Case series, Ventral 1/3 thoracotomy at 7-8th intercostal space, insert sheath catheter from heart apex to left atrium, emplace of v-clamp in mitral valve under Trans-Esophageal Echocardiography(TEE)
Result: TEER was successful in all three dogs. Size II clamp® was used in all patients. Average surgery time was 120 minutes. Recovery time varied from 2 to 7 days and was affected by MMVD stage. Size of heart was more important than weight. If annulus diameter was more than 12mm, TEER was possible. 5fr sheath was installed to femoral artery to measure arterial pressure. Because of the small heart, cardiac axis was seen as distorted on TEE, making surgery difficult. The size of the left atrium is small, details of adjusting the gap between two clamps are necessary. TEER in small hearts has a risk of postoperative mitral stenosis, so careful evaluation during surgery must be performed.

Conclusions: TEER can be done successfully with careful details under 2.5kg dogs.