Adult-Gerontology Clinical Nurse Specialist (CNS) Practice Exam

In the context of cardiomyopathy, what is a major symptom of dilated cardiomyopathy?

1. Decreased contractility

2. Thickened heart walls

3. Increased heart rate

4. Enhanced oxygenation

The correct answer is: Decreased contractility

Dilated cardiomyopathy is characterized primarily by the dilation of the heart chambers, especially the ventricles, and a decrease in the contractility of the myocardium. This condition leads to ineffective pumping of blood, resulting in reduced cardiac output. Consequently, decreased contractility is a major symptom observed in patients with dilated cardiomyopathy. The impaired contraction hinders the heart's ability to generate sufficient pressure to efficiently circulate blood throughout the body, ultimately leading to symptoms such as fatigue, shortness of breath, and signs of heart failure. The other options represent different aspects of cardiac function or pathology that do not primarily define dilated cardiomyopathy. For example, thickened heart walls are associated with hypertrophic cardiomyopathy rather than dilated cardiomyopathy. An increased heart rate may occur as a compensatory mechanism in response to decreased cardiac output but is not a defining symptom. Enhanced oxygenation does not typically describe a symptom associated with dilated cardiomyopathy, but rather pertains to the efficiency of oxygen transport in well-functioning cardiac physiology. Therefore, decreased contractility is the most accurate reflection of a major symptom associated with this condition.