Myxomatous mitral valve disease is a common disease in older dogs of small- to medium-size breeds. The mitral valve, and less commonly the tricuspid valve may be affected which causes them to leak blood from the ventricle to the atrium of the heart during systole. With increasing severity of mitral valve leakage the forward stroke volume ejected into the aorta decreases, which may lead to an increase in blood pressure in the pulmonary vein resulting in pulmonary edema. A decrease in cardiac output may lead to a decrease in blood pressure, but the body may respond in order to normalize the blood pressure. Franzén showed in 2007 that the systolic blood pressure was increased in dogs with severe mitral insufficiency. Franzén used the intensity of the heart murmur to estimate the severity of mitral insufficiency. In this study we used echocardiography for the same purpose. Both studies used an oscillometric method to determine the arterial blood pressure. We wanted to see if we could obtain similar results using an echocardiographic classification. The aim of the study was to give an overview of the disease and investigate if mitral valve insufficiency affects the arterial blood pressure.
We examined a total of 58 dogs (20 male and 38 female) of which 53 had different severity of mitral insufficiency and 5 were healthy controls. The dogs comprised 51 cavalier king charles spaniels, 4 dachshunds, one poodle, one miniature schnauzer and one shih-tzu. The dogs were 2,2-15,6 years old with a mean age of 8,8 years. The female dogs were 2,2-15,1 years old with a mean age of 8,6 years. The male dogs were 3,7-15,6 years old with a mean age of 9,2 years.
The dogs underwent a physical examination and the heart rate, body weight and presence and intensity of heart murmur was recorded. The dog’s systolic and diastolic blood pressure was measured using oscillometry and echocardiography was performed to determine the severity of mitral insufficiency.
The heart rate increased with increasing severity of mitral...
