Systolic Anterior Motion (SAM) in Cats: What You Should Know

Just like a human heart, a cat’s heart has specific mechanisms by which it controls the flow of blood throughout the body. And just like a human heart, when something goes wrong with the circulatory system, further complications are quick to follow.

One example of this fact is known as systolic anterior motion, or SAM. It’s a condition that affects the mitral valve, a crucial component of the feline heart. Normally, this valve closes during heart contractions, preventing blood from flowing back into the left atrium. However, with SAM, one of the valve leaflets bulges abnormally into the left ventricle’s outflow tract, partially blocking blood flow to the body.

For this post, Coast to Coast Cardiology going to help clarify the causes, diagnosis, treatments, and prognosis of the condition. As always, the content will serve our end goal of empowering pet owners and treating the patient, not just the symptoms.

What Causes SAM?

While SAM often occurs alongside hypertrophic cardiomyopathy (HCM), a thickened heart muscle, it can also have other causes, such as:

  • Mitral Valve Dysplasia: An abnormal valve structure present from birth.
  • Chronic Degenerative Valve Disease: Age-related wear and tear on the valve.
  • Hyperthyroidism: An overactive thyroid gland.
  • Dehydration: Both mild and severe dehydration can contribute to SAM.

Clinical Signs to Watch For

The severity of signs varies depending on the condition’s progression. Some cats might exhibit:

However, it’s also possible that SAM can be present without any outward signs. For example, while some cats have a detectable heart murmur during veterinary exams, the presence and loudness of a murmur aren’t always reliable indicators of SAM severity.

Furthermore, some cats with SAM might not have a murmur at all.

Diagnosis of SAM

An echocardiogram, an ultrasound of the heart, is used to diagnose SAM.

 The detailed imaging this provides often reveals abnormal movements of the mitral valve leaflets and potential left ventricular outflow tract obstruction when they exist.

Although this means that diagnosis is relatively straightforward (but not necessarily easy!), the process of delivering effective treatment can be trickier.

Treatment Options

As is often the case, any effective remedy depends on the severity and presence of symptoms.

  • For asymptomatic cats, monitoring might be the only initial approach.
  • In terms of medication, Atenolol is a common medication that’s used to manage outflow tract obstruction in feline patients.
  • Diuretics like furosemide can manage fluid buildup in cases of heart failure.
  • For cats with advanced heart disease, restricted activity is recommended, allowing them outdoors only with supervision.

Follow-Up Care

Regular checkups with echocardiograms are crucial for monitoring SAM progression, especially in asymptomatic cats. The frequency of these checkups depends on the severity and how quickly the condition progresses, and luckily, our team is always standing by to help.

Prognosis for Cats with SAM

The prognosis for cats with SAM depends on the severity and presence of complications. Cats with mild, asymptomatic SAM often live long and healthy lives. However, the prognosis worsens with complications like heart failure or blood clots.

If you have any concerns about the cardiovascular health of your pet, the best thing you can do is come see us! At Coast to Coast Cardiology, we have ten different locations, but we deliver on one goal no matter what: treating the patient, not just the signs. To make an appointment, contact us online or call 844-582-3827 today.