Cardiac Involvement in Juvenile Dermatomyositis: Beyond Skin and Muscle

What Is Juvenile Dermatomyositis?

Juvenile dermatomyositis (JDM) is a form of autoimmune disease affecting the skin, muscles, and tiny blood vessels. Juvenile dermatomyositis typically occurs in children between the ages of two and fifteen. Juvenile dermatomyositis is a rare kind of autoimmune disease, accounting for two to four children in one million people in the United States per year. Girls are more likely to have juvenile dermatomyositis than boys. This condition generally affects the integumentary and muscular systems while showing no impact on the body's vital organs. Nevertheless, it is known that severe cases of juvenile dermatomyositis can be associated with inflammation of the heart muscle or respiratory muscle while indirectly influencing cardiovascular function.

What Are the Signs and Symptoms Associated With Juvenile Dermatomyositis?

Juvenile dermatomyositis is primarily characterized by muscle weakness and skin rashes. This occurs as a result of inflammation in the tiny blood vessels. The inflammation of tiny blood vessels is usually termed vasculitis.

The other symptoms associated with juvenile dermatomyositis include the following.

• Red or violet-colored rashes are seen on cheeks, face, chest wall, back of elbows, or knees.

• Muscle weakness is often in the trunk, shoulders, neck, or back.

• Raised bumps on skin tissue.

• Dysphonia (distorted voice).

• Fever.

• Fatigue.

• Daily functions like climbing stairs, getting dressed, eating, and even moving the head are difficult.

• Frequent falls and injuries.

• Swollen joints.

• Dysphagia (difficulty swallowing).

• Severe abdominal pain due to the ulcers in the digestive system. The ulcers result from the inflammation of the tiny blood vessels.

• Respiratory problems are due to the inflammation and thickening of the smaller air passages in the lungs.

• Heart-related concerns are due to inflammation of the cardiac muscle surrounding the heart.

• Calcinosis (hardened lumps beneath the skin due to calcium accumulation).

What Is the Pathophysiology of Juvenile Dermatomyositis?

Juvenile dermatomyositis is a common type of inflammatory myositis in children. The pathology of this condition contributes to vasculopathy and endothelial dysfunction.

Vasculopathy:

Vasculopathy generally refers to certain diseases characterized by the involvement of abnormal structures and functions of blood vessels. This could include various blood vessels, including arteries, veins, and capillaries. This mechanism of juvenile dermatomyositis can impair the blood flow, affecting various organs and tissues.

Endothelial Dysfunction

The endothelium is generally the inner lining of the blood vessels. This layer is crucial to the blood clotting mechanism, vascular tone regulation, and certain degrees of immune responses generated in the body. Hence, endothelial dysfunction refers to the impaired functioning of the inner lining of any vessel. Endothelial dysfunction eventually diminishes the ability of the endothelium in various mechanisms like producing vasodilators, preventing blood clot formation, and managing inflammation. Endothelial dysfunction is considered a pivotal attribute in the development of cardiovascular disorders. This impact is significant because of the disruption of the normal regulatory function or impediment of the blood vessels, potentially resulting in hypertension and atherosclerosis. Atherosclerosis refers to the accumulation of fatty deposits in the bloodstream, followed by a rupture.

How Does Juvenile Dermatomyositis Influence Cardiovascular Health?

Though this condition in children primarily affects the muscles and skin, its impact on cardiovascular health is mostly secondary. So, juvenile dermatomyositis has no direct impact on the cardiovascular system. In certain cases, the inflammation associated with this condition can distend and worsen in a way that affects tissues around the heart, resulting in conditions like pericarditis, where the sac around the heart becomes inflamed.

Moreover, the involvement of respiratory muscles could also contribute to respiratory concerns, putting additional strain on the heart. Hence, this condition indirectly influences cardiovascular function. The systemic nature of autoimmune responses in this condition might contribute to generalized inflammation, potentially affecting the tiny blood vessels and cardiac tissues. The clinical findings state that not all JDM cases result in cardiovascular problems; the condition’s systemic inflammatory nature could create problems that could indirectly influence the heart and its affiliated structures.

What Are the Effects of Juvenile Dermatomyositis on Cardiovascular Health?

Cardiac involvement in juvenile dermatomyositis is mostly undetermined. Suppose cardiac involvement exists in the inflammation of the cardiac muscle. In that case, the specified individuals might have a poor prognosis, as the cardiac condition can indicate an unfavorable outcome.

The clinical findings suggest that cardiac involvement is rare in the cases of juvenile cardiomyocytes. However, cardiac dysfunction could occur in acute and chronic juvenile dermatomyositis phases. Here are a few common cardiac complications associated with juvenile dermatomyositis.

• Hypertension: Hypertension refers to increased blood pressure. The chronic inflammation associated with juvenile dermatomyositis affects the blood vessels, potentially culminating in increased resistance exerted on the bloodstream. As a result, there can be elevated blood pressure. Moreover, corticosteroid therapy usage in this condition is also attributable to hypertension.

• Atherosclerotic Heart Disease: Atherosclerosis is an accumulation or buildup of fats within the blood vessels. Juvenile dermatomyositis does not directly contribute to atherosclerosis. Chronic inflammation for a persistent time could damage the lining of blood vessels, triggering the development of fatty buildup in the bloodstream.

• Acute Congestive Heart Failure: Acute heart failure is a sudden yet life-threatening condition in which the heart and the vascular system are not involved in its function. Various factors are attributed to the occurrence of acute congestive heart failure. Juvenile dermatomyositis involving the specified blood vessels supplying the heart, called coronary arteries, might result in coronary artery disease, further increasing the risk of cardiac failure.

• Myocarditis: Myocarditis is the inflammation of the myocardium, a kind of heart muscle. The myocardium is the middle layer of those covering the heart. The chronic inflammatory condition associated with juvenile dermatomyositis could typically affect the muscles, including the heart. This can eventually weaken the pumping potential of the heart, worsening the condition even further.

• Complete Heart Block: There is no direct association between juvenile dermatomyositis and total heart block. Nevertheless, certain autoimmune conditions could have a diverse effect on disparate organ systems in the body.

Conclusion:

There is no direct impact of juvenile dermatomyositis on the cardiovascular system. However, clinical studies have determined that juvenile dermatomyositis can be associated with cardiovascular abnormalities like hypertension, coronary artery disease, and atherosclerosis owing to various determinants. Hence, monitoring the blood pressure, body mass index, and other essential laboratory tests might aid in detecting various abnormal aspects in children with juvenile dermatomyositis.