Preservation of myocardial high energy phosphates during cardioplegic arrest with nifedipine.

摘要: Nifedipine used both as an additive to cardioplegia solution (CPS) and pretreatment prior arrest was studied in a rat model determine its effect upon ischemic ventricular electromechanical work during high energy phosphate levels. Fifty-one normothermic rats were vivo with infusion of hypothermic (4°C) CPS into the cross-clamped aortic root according one following eight protocols: Group 1, baseline beating hearts; 2, containing 15 mEq potassium chloride/liter (KCl/liter); 3, 30 KCl/liter; 4, KCl/liter combined stimulation vagus nerve; Groups 5 6, 250 or 500 μg nifedipine per liter; 7 8, 100 200 nifedipine/kg given intravenous bolus min KCl/liter. Time arrest, number contractions after cross clamping, ATP creatine (CP) levels recorded. All groups arrested more quickly fewer had CP higher than those 2 (P < 0.05). There no differences between 3 except that 8 (200 μg/kg pretreatment) resulted 5, 6 0.05 for all groups). When combined, time correlated negatively (r = −0.863, P 0.01) −0.824, The cross-clamping also −0.896, −0.830, depleted 1.5 1.6 times rapidly ATP. We conclude (1) there is direct relationship myocardial stores cardioplegic (2) sensitive index depletion ATP, (3) results greater preservation obtained alone addition nifedipine.