This video is unavailable because we were unable to load a message from our sponsors. If you are using ad-blocking software, please disable it and reload the page. Embed Code Restart Playing WATCH MORE VIDEOS FROM THIS EPISODE > Stroke is the third-leading cause of death in the United States, and chief medical officer of Pfizer, Dr. Freda Lewis-Hall, joins E.R. physician Dr. Travis Stork to discuss warning signs and prevention tips for the condition. ShareTweet