Abstract
Plasma N-terminal proBNP (NT-proBNP) concentration is measured for determining the diagnosis and the severity of heart failure in dogs. However, it is still unclear whether measurements of circulating NT-proBNP levels provide clinical utility as an indicator of therapeutic efficacy. Thus, we investigated the surgical correction-related changes of plasma NT-proBNP concentrations in 9 dogs with patent ductus arteriosus (PDA). Physical examination, thoracic radiography, and echocardiography were conducted in both pre- and post-operation. Similarly, plasma NT-proBNP concentrations were determined using an enzyme immunoassay for canine pro-BNP. Compared to pre-operation, International Small Animal Cardiac Health Council (ISACHC) class and murmur grade were significantly improved in post-operation. Vertebral heart size (VHS) and cardio thoracic ratio (CTR) were significantly decreased in post-operation. Fractional shortening was significantly decreased and relative wall thickness (RWT) was significantly increased in post-operation. Furthermore, plasma NT-proBNP concentrations were significantly decreased by surgical correction. Plasma NT-proBNP concentration showed significant positive correlation with the ISACHC class, murmur grade, VHS and CTR, and significant negative correlation with the RWT. Therefore, measurement of plasma NT-proBNP levels can be used to monitor the effectiveness of therapies such as surgical correction of PDA.
