A patient's heart exhibits chronically elevated end-systolic volume. Which mechanism explains why this increased volume diminishes overall cardiac efficiency?

💡 Explanation

Increased end-systolic volume elevates the end-diastolic volume and increases the preload, thus reducing stroke volume because the heart muscle is overstretched, decreasing the force of contraction according to the Frank-Starling mechanism. Therefore, stroke volume declines rather than preload responsiveness being the primary driver.

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