A complete medical history should be obtained and your veterinarian should complete a thorough physical examination. Medical tests are needed to establish the diagnosis, exclude other diseases, and determine the impact of this disorder on your pet. The following diagnostic tests are often recommended: A thorough physical examination. Special attention is paid to auscultation (stethoscope examination) of the heart. Heart murmurs, abnormal heart sounds, and irregular heart rhythms may indicate a problem with the heart.
Thoracic radiographs (X-rays of the chest) to identify heart enlargement and fluid accumulation in the chest
An electrocardiogram (EKG). While this test is often abnormal with serious heart disease, it can be normal in many other pets with heart disease.
An echocardiogram (ultrasound examination of the heart). This test is required for establishing the diagnosis of DCM. Important examination issues include the size of the heart and the ejection fraction (ability of the ventricle to contract). This examination may require referral to a specialist.
Your veterinarian may recommend additional diagnostic tests to exclude or diagnose other conditions, or to understand the impact of dilated cardiomyopathy on your pet. These tests insure optimal medical care and should be selected on a case-by-case basis. Examples include:
Complete blood count (CBC). This blood test may be needed to identify anemia or other problems such as infections or inflammations.
Serum biochemistry tests. This blood test is especially important if there is heart failure or complications in other organs.
Thyroid test to exclude hyper-function
Urinalysis to evaluate kidney function
Heartworm test if prevention has not been given
The principles of therapy depend on the presentation or current condition of the pet. If symptoms are severe, hospital therapy is necessary. Precise treatments depend on the problems caused but may include: treatment of congestive heart failure, control of an arrhythmia (abnormal heart rhythms), management of renal failure (kidney failure), treatment of hypotension (low blood pressure) or shock caused by severe heart failure, or treatment of complications of thrombosis (blood clots).
Hospital treatment of severe congestive heart failure includes oxygen, the diuretic furosemide (Lasix®), and often nitroglycerin or nitroprusside. If blood pressure is low or heart function very bad, the drug dobutamine (a stimulant of heart contraction) is often recommended for 24 to 72 hours. Therapeutic thoracocentesis (tapping accumulated fluid from the chest cavity to improve breathing) is the best treatment for a large pleural effusion (fluid around the lungs).
When present, chronic congestive heart failure (CHF) is managed with drug therapy, including a diuretic, angiotensin converting enzyme inhibitor (such as enalapril. or benazepril, and digoxin. Pimobendan is another drug that may be used in some cats.
The diet is changed to reduce sodium intake.
Nutriceuticals (e.g. taurine pills, L-carnitine) are recommended in very specific instances.
In cases of arrhythmogenic dilated cardiomyopathy, drugs that regulate the electrical heart rhythm are indicated. If atrial fibrillation is present, digoxin often combined with either a beta blocker or a calcium channel blocker drug is prescribed.
Cats with DCM are often affected by thromboembolism, and special treatments (anticoagulants) are needed. Blood clots are usually treated with medications to control pain and prevent expansion of the clot. "Clot-busting" drugs (TPA, streptokinase) have been used effectively in cats, but they have so many very serious side effects that they are essentially impractical.