Cardiac infarction follows disease or occlusion of the coronary arteries. In 90% of cases it is due to atheroma with final occlusion by thrombosis; embolism accounts for the remainder. The records of the last one hundred post-mortem examinations on patients over forty-five years of age at the City Mental Hospital, Leicester, indicate that marked coronary sclerosis or atheroma with more or less occlusion occurred in 23 cases—II males and 12 females. In 5 the occlusion was almost complete, with fibroid degeneration of the myocardium, whilst in 2 cases, those to be described, occlusion was complete and followed by infarction.