Chihuahua & Heart Disease
Chihuahuas, like many small breeds, are predisposed to MMVD. The condition typically develops in middle age and progresses slowly. Many Chihuahuas live with a heart murmur for years before requiring treatment. Chihuahuas are also predisposed to patent ductus arteriosus (PDA), a congenital defect that is usually detected in puppyhood and can often be corrected surgically.
Photo: Unsplash
Heart conditions in Chihuahuas
Myxomatous Mitral Valve Disease (MMVD)
High riskMMVD is the most common heart disease in Chihuahuas, particularly in middle-aged and older dogs.
Patent Ductus Arteriosus (PDA)
Moderate riskChihuahuas are among the breeds predisposed to PDA, a congenital heart defect.
Screening recommendations
Start screening at
5–6 years old (or earlier if murmur detected)
Frequency
Annually once murmur is detected (echocardiogram)
Recommended tests
Cardiac auscultation, Echocardiogram
Genetic factors
MMVD in small breeds like Chihuahuas is polygenic. There is no single genetic test, but breeding dogs should be screened for heart murmurs before breeding.
Common medications
Medications are determined by your veterinarian based on your dog's individual condition. This list represents commonly used medications for this breed's typical cardiac conditions.
Prognosis
Generally favorable with monitoring. Many Chihuahuas with MMVD Stage B1 remain stable for years. Their small size means medication dosing requires precision. With treatment at Stage C, many live 1–2+ years comfortably.
Recommended reading
Other breeds at risk
Disclaimer:This content is for educational purposes only. It is based on published veterinary research and community experience, but is not written by a veterinarian and does not constitute medical advice. Every dog is different. Always consult your veterinarian or a board-certified veterinary cardiologist before making any changes to your dog's care, diet, or treatment plan.