Earliest event in ischemic cardiac myocytes is:: (A) Microvascular injury, (B) Irreversible cell injury, (C) Loss of contractility, (D) ATP reduction to 50% normal.
Answer is C. Loss of contractility Features Time Onset of A TP depletion Seconds Loss of contractility <2 min A TP reduced to 50% of normal to 10% of normal 10 min 40 min Irreversible cell injury 20-40 min Microvascular injury > 1 hour