Prevalence of mitral valve regurgitation in 102 apparently healthy Dachshunds

Mitral regurgitation (MR) is one of the main features of myxomatous mitral valve disease which affects Dachshunds. This study aims to investigate the prevalence of MR and tricuspid regurgitation, valvular thickening, and prolapse based on echocardiography in apparently healthy Dachshunds.

One-hundred two privately owned, apparently healthy Dachshunds, recruited via the Swedish Dachshund Club,^a were included in the study. It is a prospective observational study, where the presence of a cardiac murmur, echocardiographic evidence of MR and tricuspid regurgitation, subjective valvular thickening, and prolapse were investigated.

Echocardiographically detected MR was present in 64 (63%) dogs, mitral valve thickening in 46 (45%) dogs, and mitral valve prolapse in 11 (11%) dogs. A systolic murmur was heard over the mitral area in five (5%) dogs. Tricuspid valve regurgitation was present in 40 (39%) dogs, whereas tricuspid valve thickening was present in 17 (17%) dogs. There was a significant difference in age between dogs with MR (median: 5 years) and dogs without MR (median: 2.5 years), P<0.0001. There was a 50% probability that a dog had MR at the age of 2.8 years.

Whether or not the presence of MR reflects early stages of myxomatous mitral valve disease cannot be ascertained without the use of histological examination of the mitral valves.

Mitral regurgitation based on echocardiography was a common finding in this group of Dachshunds, whereas an audible murmur was not. The prevalence of MR increased with age, but MR was common in Dachshunds younger than five years.