The cause of death for pigs in transit is usually assumed to be heat exhaustion or stress, and a full autopsy is rarely performed. This study autopsied pigs that died, or would be euthanized after transport, from two packing plants. 84% of the autopsies showed abnormal hearts, and so from that point on a procedure for examining the hearts was put into practice, as well as the full autopsy. The hearts were stored in formalin for 24 hours, weighed, sectioned, and examined by the same project pathologist. The lesions observed on the affected hearts were classified as Hypertrophic Cardiomyopathy like Lesions (HCML) due to the similarity to the lesions found in humans, dogs, and cats with HCM. To determine the prevalence of  HCML in the general pork population, 51 additional hearts from pigs that did not die in transit were examined. It was found 50% of the control hearts also had lesions, but were not pronounced enough to cause heart failure when under the stress of transport. Since HCM is a genetic heart condition, an attempt was made to survey the genetic lines from farms that produced pigs with heart lesions, but there were not enough participants to provide information. Future work might look at the genetic lines contributing to HCML occurrence in pigs, and then in-transit deaths could be reduced by selectively breeding to improve heart condition. At this point, temperature control and reducing stress can help reduce in-transit deaths by avoiding triggering heart failure in susceptible animals.