AHA past president, Ralph L. Sacco, MD, MS, FAHA, FAAN offers perspective (via Skype) on ISC 19 abstract 8. He is Chairman, Department of Neurology; Olemberg Family Chair in Neurological Disorders; Miller Professor of Neurology, Public Health Sciences, Human Genetics and Neurosurgery; Executive Director, Evelyn F. McKnight Brain Institute; Senior Associate Dean for Clinical and Translational Science; Director, Clinical and Translational Science Institute; Chief of Neurology Service, Jackson Memorial Hospital in Miami, Florida; President, American Academy of Neurology 2017-19.
copyright American Heart Association 

"Infective endocarditis occurs usually when an infection can get in the bloodstream, so people who abuse IV drugs, people who inject drugs in their veins. That can often be with a contaminated needle or other contaminations can occur then lead to an infection, seeding the valves in the heart, leading to a clot that then breaks off and blocks an artery in the brain."