Abstract
Background:
In congestive heart failure (CHF), the heart cannot deliver sufficient blood for the metabolic needs of the tissues, leading to vascular changes and organ dysfunction (e.g., kidney and liver).

Aim:
This study aimed to evaluate the effects of current standard therapy on kidney and liver hemodynamic changes in dogs with congestive heart failure.

Methods:
Renal and hepatic Doppler ultrasonography was performed in 15 dogs diagnosed with stage C and D heart failure according to the American College of Veterinary Internal Medicine classification. As a current standard therapy, pimobendan, enalapril, and furosemide were administered to dogs for 4 weeks. Doppler ultrasound findings and serum biochemistry values of the patients were evaluated before and at weeks 1, 2, or 4 of treatment. The control group consisted of 10 healthy dogs.

Results:
Heart failure was diagnosed in the dogs by an echocardiographic evaluation. The values of hepatic and renal resistive index (RI), renal pulsatility index (PI), and hepatic vein systole-diastole ratio were deteriorated in the dogs with CHF compared with those in the healthy control group (p < 0.05). Hemodynamic abnormalities in the kidney and liver started to recover after a 2-week treatment period.

Conclusion:
Doppler ultrasonography findings demonstrated that heart failure worsens the vascular hemodynamics of the kidney and liver in dogs. Congestive heart failure treatment may improve the cardiorenal and cardiohepatic changes due to CHF.

Key words: Cardiohepatic syndrome; Cardiorenal syndrome; Dog; Doppler ultrasonography; Heart failure.