Endocardiosis is a condition commonly affecting dogs such as the Cavalier King Charles Spaniel.
In this condition, they heart valves “shrivel” and become leaky. Initially this causes a heart murmur, which your vet may be able to hear when conducting a check-up.
Our advice for monitoring and treating these conditions has changed recently, with the advice now being to perform a cardiac ultrasound when the condition is found, and for medication to be commenced as soon as any secondary changes are noted to the heart.