2018 ACVIM Forum Research Abstract Program: Seattle, Washington, June 14 - 15, 2018

The purpose of this study was to assess the effectiveness of mitral valve plasty (MVP) for treating pulmonary hypertension (PH) secondary to mitral valve disease in dogs. Twenty-three dogs (7-14 years of age) with preoperative PH, that underwent MVP under cardiopulmonary bypass between 2014 and 2017, were included. PH was diagnosed if the peak tricuspid valve regurgitation (TR) velocity was >3 m/s at echocardiography. Cardiac examination was performed before the operation and during follow-up (1 month, 3 months). Sildenafil was administered to dogs with residual PH if severe right-side heart overload (flattening of ventricular septum) and/or clinical signs (exercise intolerance, cyanosis) were observed. Median TR was 3.4 m/s (range 3.1-4.4 m/s) at preoperative examination. There were no deaths due to residual PH until 3 months after surgery. PH was improved in 9 (45%) patients at 3 months. TR disappeared in 4 patients and TR velocity was decreased in 5 (median 2.5 m/s; range 2.1-2.9 m/s). Eleven (55%) patients exhibited residual PH. Median TR was 3.3 m/s (range 3.0-3.7 m/s). Sildenafil was administered to 2 (18.2%) patients.