What is the primary characteristic of dilated cardiomyopathy?

The primary characteristic of dilated cardiomyopathy is the dysfunction of the heart muscle due to an enlarged heart. In this condition, the heart's chambers, particularly the left ventricle, become dilated, which means they increase in size. This enlargement leads to a decrease in the heart's ability to pump blood effectively, resulting in symptoms such as fatigue, shortness of breath, and fluid retention.

This condition is primarily structural, as the enlargement of the heart muscle affects the overall contractility and efficiency of the heart. Patients often face challenges with their heart's ability to circulate blood adequately throughout the body. Eventually, this can lead to heart failure if not properly managed.

In contrast, the other choices refer to different cardiac conditions or features. Thickened heart walls are associated with hypertrophic cardiomyopathy, while issues with heart electrical signals relate to various arrhythmias, not specifically to dilated cardiomyopathy. Lastly, inflamed heart muscles might describe conditions like myocarditis, which also differs from the primary characteristic of the dilated heart muscle seen in dilated cardiomyopathy.