Sarcoplasmic fibrils and contraction band necrosis were studied with a peroxidase technique (Dako Envision Systems) using a desmin antibody (monoclonal anti-desmin II, 53-kDa desmin protein specificity; ICN Pharmaceuticals) (33) and with Heidenhain's iron hematoxylin, respectively (33,34).
Contraction band necrosis was seen in three of six cTnI-positive patients (50%) and one of four cTnI-negative patients (25%; P >0.
Contraction band necrosis, an early marker of irreversible myocyte injury (34, 39), was identified in 4 of the 10 nonsurvivors (without cardiac cause of death).
A classic pathologic feature most commonly observed in the heart exposed to toxic effects of catecholamines is myocardial contraction band
External to the infarct necrosis was a large layer of contraction band necrosis formed by hypercontracted, deeply eosinophilic myocardial cells with rupture of the myofibrillar apparatus in anomalous bands, with no macrophagic reaction (Figure).
The sudden cardiac arrest is most likely related to adrenergic stress, documented by the extensive, early contraction band necrosis and triggered by the terminal physical effort.
However, the concept of cardiac arrest caused by catecholamine myotoxicity associated with ventricular fibrillation is suggested by (1) the finding of contraction band necrosis or disseminated focal necrosis, as encountered in other cases,[10,15] and by (2) an experimental study in which AAS, administered in combination with exercise training, induced degenerative changes within the intracardiac sympathetic neurons of the mouse.
Histological examination revealed a mixture of necroses and contraction bands
A total of 12 samples (22%; Table 3) showed only contraction bands suggestive of very early ischemic changes of an undetermined age.
Cellular injury consisted of various combinations of contraction bands, hemorrhage, myocyte hypereosinophilia, nuclear pyknosis, and coagulation necrosis but no neutrophil infiltration.
In another study of early myocardial infarction, (26) C9 immunoreactivity was noted in 47% of cases where nonspecific histologic findings were present and defined as "no specific findings, contraction bands, and hypereosinophilia.
The cytoskeletal and contractile apparatus of smooth muscle: contraction bands
and segmentation of the contractile elements.