An athlete performs repeated high-intensity exercises, leading to increased cardiac muscle mass and contractility. What happens to the ejection fraction when the heart adapts through structural remodeling?

💡 Explanation

The ejection fraction increases because structural remodeling enhances ventricular contraction strength, leading to a greater percentage of blood ejected per beat; therefore, ejection fraction rises, rather than staying the same or decreasing which could result from valve issues.

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