Artefactual contraction band necrosis of the myocardium in fatal air crashes.

Background: The detection of conditions associated with possible medical incapacitation is a crucial component of the aviation autopsy. Acute myocardial ischemia is notoriously difficult to diagnose at autopsy, although various pathological markers may strongly support a diagnosis of acute myocardial infarction occurring just prior to the crash.

Hypothesis: Contraction band necrosis may not be a reliable indicator of acute myocardial ischemia in aircraft crashes because of the forces on myocardial tissue sustained in the crash.

Methods: Microscopic examination of the myocardium of fatal air crash occupants was compared with a control group of suicidal hanging deaths. This study examined 80 air crash fatalities and 44 age and sex matched suicidal ligature hanging controls. We assessed both the presence and extent of contraction band necrosis type lesions in both groups and scored the lesions.

Results: Contraction band lesions were seen in the left ventricular myocardium of all study groups. There was no significant difference between the contraction band score for crash victim deaths and hanging deaths. However, widespread contraction banding was significantly more common in air crash victims (p = 0.032). There was no significant difference between contraction banding in victims of impacts without a post-crash fire compared with those in crashes with a post-crash fire.

Conclusions: Contraction band necrosis-like lesions in isolation should not be considered as evidence of acute myocardial ischemia in cases of massive trauma. Severe trauma, possibly as a result of sudden stretching of the cardiac myocytes, may cause a microscopic lesion which is indistinguishable from contraction band necrosis.