Which condition is inflammation of the muscular layer of the heart?

• A. Dysrhythmias
• B. Pericarditis
• C. Endocarditis
• D. Myocarditis

Answer: (D)

Inflammation of the muscular layer of the heart is myocarditis. The heart wall has three layers: the inner lining called the endocardium, the muscular middle layer called the myocardium, and the outer lining called the pericardium. When inflammation targets the muscle itself, the myocardium becomes irritated and swollen, which can disrupt the heart’s pumping ability and its electrical signals. This distinguishes it from pericarditis, which is inflammation of the outer lining around the heart, and endocarditis, which is inflammation of the inner lining of the heart and its valves. Dysrhythmias are abnormal heart rhythms, not an inflammatory condition, though myocarditis can lead to rhythm problems.