A patient with dyspnea, orthopnea, and leg edema presents with suspected heart failure. Which pathophysiologic change most directly explains their symptoms?

• A. Increased ventricular filling pressures and backward failure due to reduced cardiac output, causing pulmonary and systemic congestion.
• B. Decreased afterload causing improved forward flow.
• C. Primary lung tissue edema due to infection.
• D. Increased atrial contraction leading to reduced venous return.

Answer: (A)