Myocardial protection during ischemic cardiac arrest. A possible hazard with calcium-free cardioplegic infusates.

A number of cardioplegic and protective solutions have been described for the reduction of cellular damage during ischemic cardiac arrest. These solutions are designed to induce diastolic arrest rapidly and to combat the various deleterious effects of ischemia. The efficacy of three different infusates (Bretschneider, Kirsch and St. Thomas' Hospital) has been compared. The results indicate that, whereas some solutions are able to afford striking protection, others may be ineffective and may exacerbate damage. Until the mechanisms underlying ischemic damage and its prevention are understood, it would seem undesirable to advocate the use of solutions containing extremes of concentration or solutions devoid of ions normally found in the extracellular fluid.