Democratic presidential primary candidate Bernie Sanders underwent surgery for a blocked artery, forcing the 78-year-old senator to temporarily cancel campaign events. A statement from his campaign on Wednesday said “[d]uring a campaign event yesterday evening, Sen. Sanders experienced some chest discomfort. Following medical evaluation and testing he was found to have a blockage in one artery and two stents were successfully inserted.” The statement said the self-proclaimed Democratic Socialist is in good spirits and will take a few days off to rest. The campaign said all events are cancelled until further notice.