What are the other Names for this Condition? (Also known as/Synonyms)

• CS (Cardiac Sarcoidosis)
• Sarcoidosis of Heart

What is Cardiac Sarcoidosis? (Definition/Background Information)

• Cardiac Sarcoidosis (CS) is an uncommon form of sarcoidosis, in which involvement of the heart is noted. Sarcoidosis is a systemic disease that can affect several parts of the body, leading to the growth of small lumps of inflammatory cells
• Sarcoidosis most commonly affects the lungs, skin, eyes, and lymph nodes. However, the heart is known to be involved in about 1 in 20 cases or less. This results in additional and severe symptoms that include arrhythmias and heart failure
• Individuals with Cardiac Sarcoidosis may have chest pain, breathing difficulties, and swollen legs due to fluid accumulation. Also, due to systemic involvement of the body, the symptoms may also include tiredness, persistent cough, rashes on the skin, and eye-related abnormalities
• Cardiac Sarcoidosis may be diagnosed by various tests, such as a chest X-ray, computerized axial tomographic (CAT) scan, and an endomyocardial biopsy, when necessary. It is important to note that a diagnosis of sarcoidosis is arrived at by excluding other conditions having similar symptoms i.e., it is a diagnosis of exclusion
• Cardiac Sarcoidosis may resolve on its own or through adequate treatment. The treatment may include steroid therapy, implantation of pacemaker, and heart transplantation, for severe cases
• The prognosis of Cardiac Sarcoidosis depends upon the severity of the condition - whether mild or severe. In case of complications that include heart blocks or heart failures, the prognosis may be guarded. In such cases, individuals have been known to succumb to the condition (sudden death)

Who gets Cardiac Sarcoidosis? (Age and Sex Distribution)

• Cardiac Sarcoidosis affects individuals of all age groups and both genders
• The incidence of cardiac involvement among the Japanese population is much higher
• In general, sarcoidosis is more prevalent in African Americans and individuals of Scandinavian, Asian, Puerto Rican, Irish, and German ancestry

What are the Risk Factors for Cardiac Sarcoidosis? (Predisposing Factors)

Following are the risk factors for Cardiac Sarcoidosis:

• Certain populations, such as individuals belonging to Japan, have a higher risk for the condition
• Age appears to be a factor, as the majority of cases diagnosed are found in individuals between 20-40 years of age
• A family history of sarcoidosis may be a risk factor

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Cardiac Sarcoidosis? (Etiology)

Currently, there are no known causes for Cardiac Sarcoidosis. It is reported that the condition may be caused by abnormalities in immune response to a variety of stimuli.

• Although, no gene has been definitively identified to cause the disease, the predisposition of certain populations implies a genetic causative factor
• Exposure to environmental toxins, such as talc and aluminum, may possibly lead to the disease as well
• It is likely that sarcoidosis develops when a genetically susceptible individual is exposed to a specific, but unknown environmental antigen that acts as a trigger
• Another possible hypothesis is that it develops via bacterial infections, such as Mycobacterial, Corynebacterium, and Mycoplasma infections, and a variety of fungal infections

What are the Signs and Symptoms of Cardiac Sarcoidosis?

The signs and symptoms of Cardiac Sarcoidosis vary from one individual to another; it may be mild in some and severe in others. Following are some of the common signs and symptoms noted:

• Fatigue
• Fever
• Weight loss
• Joint pain and swelling

Symptoms specific to the heart may include:

• Chest pain
• Congestive heart failure that can result in shortness of breath, tiredness, and swelling of the extremities
• Partial bundle branch block that can cause different types of heart rhythm abnormalities (or arrhythmias)
• Ventricular tachycardia (most common type of arrhythmia) that is observed in 25% of the patients with Sarcoidosis of Heart
• Pericardial effusion (fluid in the pericardium)

It is reported that 1 in 4-5 individuals with sarcoidosis showing lung involvement may present heart involvement too, but without exhibiting any (cardiac) signs and symptoms.

The commonly affected parts of the heart include the:

• Pericardium, myocardium and endocardium
• Wall of the left ventricle
• Papillary muscles of the heart
• Lower portion of the ventricular septum

Sarcoidosis is a systemic disease and the involvement of other organs may cause a variety of symptoms that include:

• Dry cough
• Wheezing
• Rashes or lesions (raised red lesions on the skin)
• Subcutaneous nodules
• Eye pain; irritation and redness of the eye

How is Cardiac Sarcoidosis Diagnosed?

A healthcare provider may use some of the following methods to diagnose Cardiac Sarcoidosis:

• A thorough physical examination and assessment of symptoms
• Checking medical, occupational, and family history
• Blood test including calcium, vitamin D levels, and ACE (angiotensin converting enzyme)
• Blood tests for interleukin 6 (IL-6); individuals with sarcoidosis generally have higher levels of the protein IL-6
• Tissue cultures to rule-out infectious diseases
• Imaging studies that include:
  • Chest X-ray
  • Doppler ultrasound: Sound waves are used to measure the speed and direction of blood flow
  • CT scan of the heart
  • Contrast-enhanced MRI of heart
  • Positron emission tomography (PET) scan
• Electrocardiogram (ECG): It is used to measure the electrical activity of the heart in case of arrhythmias. An ECG may show patterns that are similar to a heart infarct
• Scintigraphy using thallium‐201 and gallium‐67
• Endomyocardial biopsy: A tissue biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis

A differential diagnosis may be undertaken to eliminate the following heart conditions prior to arriving at a definitive diagnosis of Cardiac Sarcoidosis:

• Giant cell myocarditis
• Hypersensitivity myocarditis
• Lymphocytic myocarditis
• Myocarditis due to tuberculosis

Note: A diagnosis of Cardiac Sarcoidosis is generally difficult and challenging to arrive at.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Cardiac Sarcoidosis?

Cardiac Sarcoidosis may resolve over time or through proper treatment. However, the condition is known to lead to the following complications:

• Abnormal heart rhythms and conduction disorders
• Complete heart block and heart failure
• Sudden death
• In some individuals (who have undergone a heart transplantation), Cardiac Sarcoidosis can occur in the newly-transplanted heart too

Involvement of the other vital organs, such as the lungs or brain, can result in even severe complications.

How is Cardiac Sarcoidosis Treated?

Presently, there is no cure for Cardiac Sarcoidosis. It may go away on its own or may need medication to alleviate the symptoms. Many a time, if sarcoidosis affects multiple organs, then specific medication may be prescribed to restore proper function of the organs.

The following treatments may be necessary depending on the severity of the symptoms:

• Corticosteroid treatment (such as prednisone): It is the most common anti-inflammatory drug prescribed for sarcoidosis
• Use of immunosuppressant medicines, such as methotrexate and azathioprine, when the eyes, joints, lungs, and skin, are affected
• Pacemaker and defibrillator implantation
• Pericardiocentesis (removal of fluid from pericardial sac) may be performed in case of pericardial effusion
• Heart transplantation for individuals with severe symptoms and complications

How can Cardiac Sarcoidosis be Prevented?

Although prevention methods for Cardiac Sarcoidosis do not exist, the following have been suggested to reduce the risk for the disease:

• Smoking cessation; even though sarcoidosis is less common in smokers
• Limiting alcohol consumption
• Avoiding exposure to toxic fumes
• Availing vaccinations: Pneumococcal vaccine and annual flu shot recommendations, if one is not allergic to them

What is the Prognosis of Cardiac Sarcoidosis? (Outcomes/Resolutions)

The prognosis of Cardiac Sarcoidosis depends on the severity of the symptoms, complications associated with the condition, and the extent of systemic disease.

• In some individuals, the condition may not lead to severe illness and it gets better with time, with appropriate treatment. Also, in cases where the symptoms persist, medications and lifestyle changes can help bring some relief
• In addition to regularly visiting a cardiologist, regular check-ups including monitoring blood pressure, blood sugar, and strength of bones is important, especially if the patient is on steroid treatment
• Involvement of the heart in sarcoidosis can be severe; it is the cause of death in 10-25% of the affected individuals (within the US). In the Japanese population, Cardiac Sarcoidosis is the cause of death in 85% of the affected individuals
• Sudden death due to arrhythmias is reportedly the cause of death in 65% of the affected individuals

Additional and Relevant Useful Information for Cardiac Sarcoidosis:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/diseases-conditions/sarcoidosis/