Comparison of potassium and adenosine cardioplegia with or without verapamil in the isolated guinea pig heart.

1. The cardioprotective effects of adenosine cardioplegia and classical potassium cardioplegia with or without adding verapamil were investigated in isolated guinea pig heart. 2. Four different cardioplegic solutions were used to arrest the hearts which were previously perfused by Krebbs-Henseleit solution. (A) potassium 20 mMol/l. (B) Potassium 20 mMol/l + verapamil 1 micromol/l. (C) Adenosine 10 mMol/l. (D) Adenosine 10 mMol/l + verapamil 1 microgram/l. 3. Both of the adenosine-containing solutions shortened the arrest time and maintained better postischemic recovery according to the potassium cardioplegia. 4. A rapid cardiac arrest was observed when verapamil was added to cardioplegic solutions, on the contrary there was no significant effect on postischemic recovery.