Coronary artery disease is the most common heart problem in people but it almost never occurs in our pets. There are other kinds of heart disease, however, that we need to be aware of. Some of these are age related, some associated with certain breeds and some with particular species. Our pets don’t have all the medical options that we do (heart transplant, valve replacement, etc.) to treat heart disease but the majority of problems can be managed medically to maintain quality life.

HEART MURMUR
A murmur is an abnormal heart sound. It is usually the result of valvular disease although it can sometimes be associated with congenital vascular problems in the young. A murmur is not a disease but an abnormality that should be explored further (ECG, chest Xrays, blood tests, ultrasound, etc.). Murmurs in cats often indicate heart muscle disease (cardiomyopathy).
Treatment, if necessary, is determined by the cause of the murmur.

VALVULAR DISEASE
When heart valves become thickened or scarred they fail to close tightly causing the heart to become an inefficient pump. This is a common age related problem but it can also be the result of persistent infection (dental infection, etc.). It is common in certain breeds such as the Cavalier King Charles Spaniel.

We don’t have the option of replacing faulty valves but often simple, safe treatments such as vasodilators, diuretics and low sodium diets can help the heart pump more efficiently.

RHYTHM DISTURBANCES
Contraction of the heart muscle is triggered by an electrical impulse that originates in the upper chambers and then travels through specialized nerve tissue to the rest of the heart. This causes the upper chambers to contract first followed closely by the lower chambers. Anything that affects this conduction system changes the heart’s rhythm. This means that the heart can’t pump efficiently or sometimes suddenly stops.

Arrhythmias may be due to either disease of the heart muscle or the conduction system itself. Certain breeds are definitely at risk (Schnauzers, Dobermans, Boxers).

Heart rhythm is evaluated with an electrocardiogram (ECG). Treatment involves anti-arrhythmic drugs, treating underlying disease and, in certain cases, pacemakers.

CARDIOMYOPATHY
Cardiomyopathy means heart muscle disease. There are two basic kinds: dilative in which heart muscle becomes weak and the heart enlarges, and hypertrophic where the heart muscle thickens and the chambers become smaller.

The causes are usually unknown but Dobermans and Boxers are certainly predisposed. These breeds should have yearly ECG screenings to look for early signs. Hyperthyroidism is a common cause in cats. This is easily diagnosed and is a very treatable disease.