Vermont Senator and 2020 Democratic primary hopeful Bernie Sanders has canceled all of his appearances and events until further notice after having chest pains and then undergoing a procedure to clear a blocked artery.

Following medical evaluation and testing he was found to have a blockage in one artery and two stents were successfully inserted.

“During 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,” senior adviser Jeff Weaver said in a statement. “Sen. Sanders is conversing and in good spirits. He will be resting up over the next few days. We are canceling his events and appearances until further notice, and we will continue to provide appropriate updates.”

Sanders is 78 years old and one of three Democratic candidates in their 70s, including former Vice President Joe Biden, 76, and Massachusetts Sen. Elizabeth Warren, who is 70. Current President Donald Trump, the oldest elected president on record, is right there with them at age 73.

Sanders also was hospitalized shortly after announcing his plans to run in February, appearing on the campaign trail with a bandage on his head in South Carolina in March. Sanders was reportedly treated at a walk-in clinic for a minor head injury after he cut his head in the shower, according to the Associated Press. He received a dozen stitches and was given a “clean bill of health.”

The news of Sanders’ hospitalization comes on the heels of a big announcement this week that Sanders raised a staggering $25.3 million for his campaign during the third quarter, the most of any Democratic challenger this year — more than what Warren amassed during the first and second quarters combined.

Sanders also ran in 2016, losing to Hillary Clinton in the Democratic primary. Sanders is currently third according to most major polling services, trailing the front-running Biden and now trailing the hard-charging Warren.