What is Cardiac Sarcoidosis?

Sarcoidosis is an inflammatory disorder that can involve many organ systems in the body. The exact cause of this systemic disease is unknown. It typically forms granulomas (small areas of inflammation) in the lungs. However, granulomatous inflammation can also involve other organs, such as the heart, which is called cardiac sarcoidosis.

Please continue reading to learn more about cardiac sarcoidosis, including who is at risk and what health complications it can cause. We will also discuss how doctors diagnose someone with suspected cardiac sarcoidosis and the treatments available to patients.

How is cardiac sarcoidosis different from pulmonary sarcoidosis?

As mentioned, sarcoidosis usually involves the formation of granulomas in the lungs. This condition is called pulmonary sarcoidosis. Sarcoidosis can also affect other organs like the lymph nodes, eyes, skin, nervous system, musculoskeletal system, endocrine system, renal system, and heart. When granulomatous inflammation involves various organs in the body, it is called systemic sarcoidosis.

When there is cardiac involvement (heart involvement), it is called cardiac sarcoidosis. Not every patient with sarcoidosis has cardiac involvement. The cause of cardiac sarcoidosis remains unclear, although environmental and genetic factors are believed to play a role. Patients with cardiac involvement generally have poorer outcomes.

Only a tiny fraction of patients with sarcoidosis have cardiac involvement diagnosed clinically. However, autopsies in patients with systemic sarcoidosis have revealed that up to 25% have cardiac involvement. This means that cardiac sarcoidosis is an underdiagnosed condition and that clinical diagnosis is often missed.

Who gets cardiac sarcoidosis?

Sarcoidosis is frequently detected in young and middle-aged adults. In the US, African Americans have a 3-4 times higher risk of developing sarcoidosis than Caucasians.

What are the symptoms of cardiac sarcoidosis?

Patients with extracardiac sarcoidosis (systemic sarcoidosis) often present with nonspecific symptoms such as fatigue, swollen lymph nodes, joint pain, and weight loss.

Cardiac involvement (active inflammation in the heart) can lead to problems like heart block, atrial, refractory ventricular, supraventricular, and spontaneous sustained ventricular arrhythmias, ventricular tachycardia, severe systolic dysfunction, idiopathic dilated cardiomyopathy, and heart failure.

Cardiac symptoms in patients with active myocardial inflammation or cardiac lesions may include chest pain, shortness of breath, edema (swelling), irregular heartbeat, fluttering of the heart (palpitations), fatigue, fainting, and even sudden cardiac death.

How is cardiac sarcoidosis diagnosed?

It can be challenging to make an accurate diagnosis of sarcoidosis. Cardiac sarcoidosis is even more difficult to diagnose because the symptoms and clinical manifestations are nonspecific. Even advanced cardiac imaging modalities like echocardiography, cardiac positron emission tomography (cardiac PET), and cardiac magnetic resonance imaging (cardiac MRI) are not sensitive or specific enough to allow doctors to detect cardiac involvement. However, with the availability of newer cardiac imaging technologies, diagnosing sarcoidosis with cardiac involvement is becoming easier.

Is cardiac sarcoidosis curable?

Sarcoidosis is not curable. However, many asymptomatic patients have clinically silent CS, i.e., no signs or symptoms. Silent cardiac sarcoidosis may not require any treatment. Some patients may require only a modest amount of treatment. Sometimes, sarcoidosis disappears on its own without a known reason. However, in some patients sarcoidosis can be long-lasting and can cause permanent damage to the involved organs. For example, myocardial involvement in refractory cardiac sarcoidosis can lead to heart damage.

How is cardiac sarcoidosis treated?

No optimal medical therapy or suggested treatment algorithm is considered the standard treatment for patients with cardiac sarcoidosis. Therefore, the treatment is not well defined and can vary significantly from patient to patient.

The mainstay of cardiac sarcoidosis treatment is corticosteroid therapy. However, the optimum dosage or duration of steroid treatment is unclear, and there is a great deal of variation in clinical practice. Immunosuppressive therapy is generally tailored according to a patient’s clinical symptoms and imaging results.

Besides corticosteroid treatment, patients with cardiac sarcoidosis may also be treated with a steroid-sparing agent, antiarrhythmic drugs, heart failure medications, beta-blockers, renin-angiotensin system blockers, and diuretics. Other treatment modalities include programmed ventricular stimulation, ICD implantation, and catheter ablation. In patients with cardiac sarcoidosis who develop refractory heart failure, cardiac transplantation may be the last resort.

How long can you live with cardiac sarcoidosis?

You can live for about 2 years with cardiac sarcoidosis. Five-year survival in patients with symptomatic cardiac sarcoidosis is estimated to be 40–60%. However, the outcomes are not well defined.

Last word…

Cardiac involvement in patients with systemic sarcoidosis is difficult to diagnose. Even when a clinical diagnosis is made, treatment of CS patients can be challenging because there are no clearly defined clinical practice guidelines. While there is no cure for granulomatous disorders like cardiac sarcoidosis, the condition is treatable. Corticosteroid therapy (steroid treatment) is the mainstay of treatment and other treatments based on the symptoms a cardiac sarcoidosis patient presents.

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