FIRM MYOCARDIUM IN CARDIOPULMONARY-RESUSCITATION

Firm myocardium in cardiopulmonary resuscitation (CPR) is a rarely des cribed yet potentially important condition. To investigate the clinica l nature and implications of firm myocardium in CPR, we retrospectivel y analyzed 59 adult patients with nontraumatic out-of-hospital cardiac arrest who underwent open-chest CPR in the emergency department and h ad heart consistency recorded. Consistency of the myocardium varied co nsiderably between patients. Firm myocardium was noticed in 36 cases, mainly in the left ventricle (firm myocardium group). The remaining 23 hearts were not firm (soft myocardium group). Some hearts had an incr ease in their consistency during CPR. Patient characteristics were sim ilar in the two groups. The firm myocardium group showed greater base deficit on arterial blood gas analysis, suggesting more severe ischemi c injury. Very firm heart had a close association with an extremely lo w end-tidal CO, tension. Histopathological examination revealed hypert rophy and fibrosis common to the two groups. Both groups received simi lar treatment except for a shorter duration of direct cardiac massage in the firm myocardium group, although a reasonably prolonged effort w as made in most cases. The firm myocardium group responded poorly to t reatment. Very firm myocardium never contracted, whereas less firm myo cardium usually showed some, albeit insufficient, activity. Most cases in the soft myocardium group regained a pulse. Our results suggest th at firm myocardium: (1) is common in patients who receive CPR in the e mergency department, (2) indicates ischemic contracture, (3) is not un iform in firmness, reflecting the degree of ischemia and (4) is a grav e prognostic factor in cardiac resuscitation. Copyright (C) 1996 Elsev ier Science Ireland Ltd