What is the most common cause of myocarditis?

What is the most common cause of myocarditis?

• A. Bacterial
• B. Viral
• C. Drug reaction
• D. Radiation therapy

Answer: (B)

Viral infections are the most common cause of myocarditis. Many viruses can inflame the heart muscle, with enteroviruses (especially Coxsackie B), adenovirus, and parvovirus B19 frequently implicated in children. The virus can directly injure cardiomyocytes and trigger an inflammatory response that impairs heart muscle function and electrical stability. This pattern occurs far more often than bacterial infection, drug-induced injury, or radiation-related damage. Clinically, myocarditis may present with fatigue, chest pain, dyspnea, tachycardia, or signs of heart failure, and in severe cases can lead to arrhythmias or cardiogenic shock. Diagnosis relies on a recent viral illness history, elevated cardiac enzymes, ECG changes, and supportive findings on cardiac MRI showing edema and inflammation. Management is supportive, addressing heart failure symptoms and arrhythmias as needed, and most pediatric patients recover with appropriate care, though some cases can be fulminant.

Viral infections are the most common cause of myocarditis. Many viruses can inflame the heart muscle, with enteroviruses (especially Coxsackie B), adenovirus, and parvovirus B19 frequently implicated in children. The virus can directly injure cardiomyocytes and trigger an inflammatory response that impairs heart muscle function and electrical stability. This pattern occurs far more often than bacterial infection, drug-induced injury, or radiation-related damage. Clinically, myocarditis may present with fatigue, chest pain, dyspnea, tachycardia, or signs of heart failure, and in severe cases can lead to arrhythmias or cardiogenic shock. Diagnosis relies on a recent viral illness history, elevated cardiac enzymes, ECG changes, and supportive findings on cardiac MRI showing edema and inflammation. Management is supportive, addressing heart failure symptoms and arrhythmias as needed, and most pediatric patients recover with appropriate care, though some cases can be fulminant.