There are many different drugs that are used to treat heart disease and heart failure in dogs and cats. The medications chosen will depend on the type of heart disease present, the overall health of your dog or cat, and the severity of the heart disease.
These are a few of the most commonly used medications. In many cases, two or more of these medications may be required for your pet.
If congestive heart failure is present, diuretics are the most important drugs used to remove the excess fluid build-up that results from heart failure.
The most commonly used diuretic is furosemide (Lasix®). Other diuretics such as spironolactone are sometimes used as well and may be used in combination with furosemide when furosemide alone is not sufficient.
ACE (Angiotensin-Converting Enzyme) Inhibitors
ACE inhibitors are frequently used as vasodilators in heart disease. Vasodilation results in the blood vessels becoming more relaxed with larger diameters. This makes it easier for the heart to circulate the blood through the bloodstream to the various parts of the canine or feline body. It also helps lower blood pressure.
The most commonly used ACE inhibitors are enalapril and benazepril.
Pimobendan has two different actions that work to improve heart function. It acts as a vasodilator and it also works as an inotrope. An inotrope helps improve the force of the contractions of the heart.
Digoxin and Digitoxin
Digoxin (or alternatively, digitoxin) were once mainstays in the treatment of heart disease. The risk of side effects with digoxin is high and today we have safer medications which can often accomplish the same purpose for our dogs and cats. Digoxin and digitoxin are no longer as widely used as they once were.
Medications to Control Blood Pressure
High blood pressure (hypertension) can be a serious concern in dogs and cats with heart failure. High blood pressure can further contribute to heart disease as well, causing additional damage to the heart.
ACE inhibitors are the most commonly used medications in controlling blood pressure. However, when ACE inhibitors by themselves are not effective, other medications may be needed. Atenolol and amlodipine are often used for this purpose.
Medications that Reduce Blood Clotting
Particularly in cats, blood clots can occur inside of the heart and break off, leading to a condition known as arterial thromboembolism. Arterial thromboembolism occurs when the blood clot lodges in a blood vessel cutting off the circulation of the blood to part of the body.
The clots often lodge at the end of the aorta and result in the circulation to the hind legs being compromised. Thromboembolism can also occur in the pulmonary arteries, cutting off the blood to the lungs.
Medications such as aspirin or clopidogrel (Plavix®) are often used (with veterinary supervision and monitoring) to try to prevent clotting and decrease the potential for thromboembolism.
Other Supplements Used
Some types of heart disease in dogs and cats are responsive to supplements such as taurine and/or L-carnitine.
Antioxidants such as coQ10 are also often used in treating heart disease in dogs and cats.