Diagnosing Dilated Cardiomyopathy, (DCM)

DCM or dilated cardiomyopathy is common in large dogs such as Doberman Pinschers. We suspect DCM if the heart is enlarged and the walls thin. Dobys are one of the breeds that commonly develop this problem and without treatment may collapse suddenly and die.

ECG and Ultrasound
To diagnose DCM in Dobys, we use an electrocardiograph (ECG) that shows the heart rhythm and an echocardiographic ultrasound (echo), which shows the heart muscle thickness and ability to contract. All dogs can have occasional episodes of irregular heart beat, but a normal dog has less than 50 episodes of irregular rhythm each day. A dog with DCM is likely to have more than 50 episodes of irregular rhythm, and to have the type of irregular rhythm with couplets and triplets—that is, multiple episodes of irregularity in a row. Couplets and triplets increase the likelihood that the heart muscle will not be able to revert to normal rhythm and the heart will fail completely and cause sudden death.

Premature Ventricular Contractions or PVCs
In normal hearts, the signal to begin contracting comes from the upper heart, the atria, but when a heart is dilated, wiring of the heart is distorted. This distortion increases the odds that contractions will begin randomly in the lower heart chambers, the ventricles. These rapid, irregular signals from ventricles are called premature ventricular contractions or PVCs. We often find PVCs in Dobys with dilated hearts, especially in Dobys that wear an ECG monitor (Holter monitor) for a full 24 hours.

Treatment for DCM coming
Once we’ve diagnosed dilated cardiomyopathy, what can we do to help? We’ll cover treatments that help in our next entry. These treatments will include drugs, supplements, and holistic therapies.