What is a potential consequence of untreated valvular heart disease?

Untreated valvular heart disease can lead to heart failure due to impaired blood flow. When the heart valves do not function properly—whether due to stenosis (narrowing) or regurgitation (leakage)—the heart must work harder to pump blood effectively. Over time, this increased workload can lead to structural changes in the heart, such as hypertrophy (thickening of the heart muscle) or dilation of the heart chambers. As the heart becomes less efficient at pumping blood, symptoms of heart failure may develop, including fatigue, shortness of breath, and fluid retention.

Other options provided do not align with the consequences of untreated valvular heart disease. For instance, decreased respiratory function might occur as a secondary effect due to heart failure but is not a direct consequence of valvular heart disease itself. Improved blood circulation is contrary to the expected outcome, as impaired valve function decreases the efficiency of blood flow. High levels of physical endurance typically require cardiovascular efficiency and health, which are compromised in individuals with untreated valvular issues.