What happens to mean arterial pressure (MAP) when the cardiac muscle's contractility diminishes due to prolonged ischemia?

💡 Explanation

When cardiac muscle contractility decreases, stroke volume and cardiac output drop, because the heart can't pump blood effectively. Therefore, the mean arterial pressure decreases because it's directly proportional to cardiac output and systemic vascular resistance, rather than being maintained by baroreceptors or increased by vasoconstriction alone.

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