Evaluation of aging on muscle blood flow in conscious healthy dogs by duplex Doppler ultrasonography.

According to a study conducted on a population of 9,248 subjects, cardiac diseases are the second most prevalent cause of death in the dog. During the last decades, a common scenario has been the increase on life expectancy of dogs. The exact relationship between the negative modifications of cardiovascular function and the development of specific cardiovascular diseases is difficult to ascertain, and also, the effect of age per se on vascular impedance is important. It may result in limited cardiovascular reserve under conditions of increase demand in senescent animals. To evaluate the effect of age on the peripheral vasculature specifically, the objective of this study was to compare parameters of the regional blood flow as well as compliance and resistance indexes in the femoral arterial system of younger and older conscious healthy dogs by duplex Doppler ultrasonography. The data were collected from 16 mixed-breed dogs divided into two groups: young and old healthy dogs. In all dogs Doppler spectra blood flow patterns of the femoral artery were triphasic. Significant differences were not found between the parameters measured for young and old groups. Despite this, the average value of femoral flow volume in the older group was approximately 50% lower than the younger group. This finding could play an important role in limiting exercise response with age. In order to validate these speculations, further studies should be performed in aged dogs.