Potential definition of the time of death from autolytic myocardial cells:a morphometric study

Morphometric methods and transmission electron microscopy were used to quan tify modifications occurring in the mitochondria of dog myocardium during t he first four hours of autolysis. Myocardial fragments were obtained from t he outer free wall of the left ventricle, during anesthesia (control-zero) and at 15, 45, 120, and 240 min after cardiac arrest, maintaining the heart "in situ" at 22 degrees C. During the 240 min of autolysis, the main param eters evaluated showed: (a) a decrease in the number of mitochondria from 0 .31 to 0.12 per mu m(3) of cytoplasm. The decrease over the first 45 min re ached 50% of the initial value; (b) an increase in mitochondrial volume, th ree times greater after the first 45 min (from 0.92 to 2.68 mu m(3)) and fo ur times greater after 240 min (from 0.92 to 3.79 mu m(3)); (c) an increase in mitochondrial outer membrane surface area from 5.51 to 12.54 mu m(2); ( d) an increase in the surface area of individual mitochondria inner membran e and cristae from 27.60 to 56.96 mu m(2). The progressive nature of the al terations and the difference in the numerically expressed values allow corr elation with the time of somatic death. The authors emphasize the need for further studies in order to complement the present study. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.