Cardiac Murmur (Heart Murmur)

A cardiac murmur is an abnormal heart sound heard by placing a stethoscope on the chest. Murmurs can vary widely in intensity and cause. They are classified by grading them on a scale of 1-6 for loudness and by several other factors.

Grade 1 and Grade 6 Murmurs

A grade 1 murmur is very faint and often can only be heard in a quiet room. A grade 6 murmur's vibrations are strong enough to be felt by placing a hand on the chest over the heart.

Murmurs can change in intensity with heart rate, dehydration, fever, stress and worsening of pre-existing heart or lung disease.

Are heart murmurs related to heart disease?

Heart murmurs do not always equate to heart disease, especially if they are very low grade. Young pets can sometimes have low grade "innocent" murmurs that fade as the pet grows. However, murmurs are an important indicator of potential cardiac problems. This is especially true if the murmurs worsen over time or are accompanied by any pre-existing heart or lung problems.

Diagnosis and Treatment of Heart Murmurs in Dogs and Cats

Diagnosis of potential heart disease may require a cardiac work up including x-rays, ECG (electrocardiogram), blood work, and in some cases, ultrasound. Treatment varies widely depending on the underlying problem. Dietary changes and many medications exist that can significantly help cardiac patients.

Post-Care and Prevention Tips

  • Use all medications as prescribed by your veterinarian.

  • Monitor your pet's progress carefully and have him/her rechecked as recommended by your veterinarian.

Learn More

If you have questions about this or any medical topic, please contact your Banfield hospital today.