Prospective evaluation of renal function in dogs with chronic mitral valve disease

The coexistence of renal and cardiac disease has been defined in dogs and cats as cardiovascular-renal disorders (CvRD). In humans, renal function is affected by recurrent episodes of acute congestive heart failure (CHF). The aim of this prospective, case-control study was to evaluate the appearance and influence of worsening cardiac disease (WCD), defined on echocardiographic and radiographic parameters, on renal function (defined as worsening renal function [WRF], on the basis of serum creatinine level and presence of proteinuria) in two population: 21 dogs with chronic mitral valve disease (CMVD) and 20 healthy dogs. Dogs were sorted into groups according to the presence/absence of WRF or WCD. Statistical analysis was performed between CMVD dogs and healthy dogs and inside the CMVD dogs group. There was no statistically significant difference in developing WRF between dogs with/without WCD and no statistical evidence to support a difference in WRF parameters in dogs experiencing CHF and dogs not experiencing it. The prevalence of azotemia in CMVD dogs was significantly higher than the prevalence of azotemia previously reported in the general population of dogs. Diuretics therapy didn’t affect renal function. No difference in survival time was seen between groups. In conclusion, CHF, WCD and diuretics therapy didn’t directly induce WRF. However, considering the prevalence of azotemia, data suggests a link between heart and kidney function (despite we didn’t excluded aged-related coexistence of organ damage). A bigger number of dogs at inclusion is required to reach statistical significance.