Which intervention increases myocardial contractility, shifting the Frank-Starling curve upward rather than moving along it?
Answer and explanation
Correct answer: A. Digoxin
- Step 1: Contractility changes move the whole curve; preload changes move the point along the curve. Step 2. Digoxin raises intracellular calcium and contractility. Answer: digoxin. Why not the others: more venous return moves along the same curve, beta-blockers lower contractility, and higher afterload lowers stroke volume.
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