With little training in physics, Guglielmo Marconi developed the invention that stunned the world by wirelessly connecting ships and continents. Ten years before his death, he sustained a myocardial infarction followed by unmistakable angina pectoris. His personality and unhappy family life limited his ability to cope with his disease and to deal with Italy's most respected physicians. But their descriptions of his diagnosis and management are surprisingly few. Poor record keeping, intentional news suppression of his failing health or limited medical opportunities could be the reason for this lack of information. He died in 1937 when the value of electrocardiograms and X-rays were recognized (he had neither), but therapeutic options were severely limited. To gain insight into his care, we compared contemporary Italian understanding of coronary heart disease to British and American teachings. When he died of an acute coronary syndrome, heart failure and dysrhythmias, he was attended only by medical staff, but by none of his large family.