Better short-term survival in dogs after mitral valve repair surgery

Abstract

OBJECTIVE: To describe a structured approach to the development of a mitral valve repair (MVR) program for dogs with myxomatous mitral valve disease (MMVD) and to document the change in short term outcome over time. STUDY DESIGN: Clinical prospective study. ANIMALS: Dogs (n = 132) with MMVD undergoing MVR at a single hospital. METHODS: Using a carefully structured multidisciplinary approach to patient selection, surgical treatment, and postoperative care that incorporated both "reflective" and "deliberate" practice, we embarked on an MVR program alongside our pre-existing open heart surgery program. Data were gathered for the first 132 dogs undergoing MVR in this program (between July 2015 and November 2022). Short-term survival was defined as dogs that were discharged from the hospital. The dogs were divided into four groups of equal size based on chronological order and the data within each group compared using descriptive statistics. RESULTS: The breeds most represented were Cavalier King Charles Spaniels (CKCS) and Chihuahuas. The MMVD was categorized clinically as stage D in 36/132 (27%), stage C in 88/132 (67%) and stage B2 in 8/132 (6%) of affected dogs. Overall, 107/132 (81%) of the dogs survived to discharge. A consistent trend of improved short-term outcome was observed, with survival rate of 22/33 in the first quartile, 27/33 in the second quartile, 28/33 in the third quartile, and 30/33 dogs in the fourth quartile. CONCLUSION: A structured organized approach by a team of consistent personnel resulted in an improvement in outcome over time. This improvement most likely reflected improvement in both technical and non-technical skills within this complex sociotechnical environment. CLINICAL SIGNIFICANCE: What constitutes an acceptable performance for MVR in the dog has not been defined so the number of cases that constitute the "learning curve" during program development and the number of cases required in the "skills maintenance" phase remain unknown. The data reported here, however, describe the level of organizational commitment and the case throughput required to begin the process of establishing a successful MVR program and as such, should be useful to any team considering this therapy.