What is Dilated Cardiomyopathy in Dogs and Cats & When to Seek Emergency Vet Care

• Coughing   

• Increased breathing, increased effort to breathe, difficulty lying down  

• Lethargy, weakness , reluctance to play or walk (tiring easily)  

• Fainting or collapse, cold extremities (ears, legs)  

• Swollen abdomen (ascites), sometimes swollen legs  

• Decreased appetite, weight loss  

It is an EMERGENCY if your pet has:  

• Labored, rapid, or open-mouthed breathing  

• Persistent coughing or gagging (especially with fluid in the lungs)  

• Fainting, weakness, or collapse  

• Pale, grey, or blue-tinged gums or tongue  

• Abdominal swelling/distension   

You should schedule a non-emergency appointment with your vet if you observe more subtle or gradual changes that may still be signs of developing heart disease such as lethargy, reduced exercise tolerance, reduced eating, and unexplained weight loss.  

• History and clinical examination from your vet  

• Blood test, X-rays, and ultrasounds  

• Other possible tests such as ECG/Holter  

DCM is most often treated with medications that help to decrease the workload of the heart or improve the efficiency of the heart’s work, and to remove any fluid from the lungs to make breathing easier:  

• Diuretics such as ‘furosemide’ and ‘spirinolactone’, to help remove fluid (from the lungs and belly)  

• Inodilators such as ‘pimobendan’, to help the heart pump more effectively  

• Anti-arrhythmic drugs if your dog has an irregular heartbeat  

• Additional supplements - some dogs with DCM benefit from heart supplements such as L-carnitine, taurine and certain fish oils (always speak to your vet before starting your pet on a supplement)  

Preventing DCM involves regular vet check-ups, maintaining a healthy weight, sensible exercise, and, crucially, feeding a high-quality, grain-inclusive diet with sufficient animal protein and taurine and being aware of genetic predispositions by screening breeding animals.    

With Dilated Cardiomyopathy (DCM), the outlook is generally poor, often fatal, but highly variable: early diagnosis, breed, and underlying cause (especially taurine deficiency in cats/some dogs, or a dietary issue) can significantly alter survival, with early treatment improving quality of life for months to years, but sudden death is common, even before heart failure signs appear. Cats with taurine-responsive DCM can often be cured, while dogs with idiopathic DCM (most common) face a progressive decline.