Bloomberg releases new heart health information and calls on Sanders to do the same

Bloomberg's last annual health exam was in July and included cardiac stress testing and a stress echocardiogram, according to a letter from Dr. Stephen Sisson at Johns Hopkins University that the Bloomberg campaign shared with CNN. According to Sisson, Bloomberg's left ventricular ejection fraction was "normal" at 60-65%; his left ventricular cavity size and left ventricular function were also deemed "normal"; and his exercise capacity was described as "excellent."

Bloomberg spokesman Stu Loeser said in a separate statement to CNN that Sanders should release the same left ventricular ejection fraction data.

"Releasing this single scientific number about heart health could start to put to rest any concerns about Senator Sanders' secrecy about his recent heart attack," Loeser said. "Mike Bloomberg's doctor shared Mike's number. Will Senator Sanders ask his doctor to do the same?"

"The letters that we've released are very thorough," Sanders communications director Mike Casca told CNN in response to the Bloomberg campaign's statement, referring to doctors' letters the Sanders campaign has previously released about the senator's health.

The "ejection fraction" is a percentage figure that measures "how much blood the left ventricle pumps out with each contraction" and a normal heart's ejection fraction is between 50 and 70 percent, according to the American Heart Association. CNN chief medical correspondent Dr. Sanjay Gupta said the ejection fraction "is the single best test of the overall strength of the heart and how well the heart is pumping blood to the rest of the body."

Both Bloomberg and Sanders are 78 years old, the oldest of the current field of Democratic candidates seeking the presidency. Former Vice President Joe Biden is 77 years old; Sen. Elizabeth Warren is 70 years old; and the man they all wish to take on in November, President Donald Trump, is 73 years old.

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Sanders suffered a heart attack in October. The Vermont senator has said that he felt chest discomfort during a campaign event in Las Vegas and was "sweating profusely" -- he proceeded to visit an urgent care clinic before immediately being taken to a hospital. Doctors inserted two stents in a blocked artery, which is a relatively common procedure.

In an interview with CNN days after the procedure, Sanders pledged to release his full medical records.

"The people do have a right to know about the health of a senator, somebody who's running for president of the United States. Full disclosure," he said.

In late December, the Sanders' campaign released three letters from physicians attesting to his good health.

The release included results of a graded exercise treadmill examination, which showed that Sanders performed well in without any evidence of reduce blood flow to the heart. The letters also stated Sanders no longer is in need of several heart medications he was taking shortly after the heart attack.

Sanders said in a subsequent CNN town hall that he believed those letters amounted to a "detailed report."

"And by the way, you think I'm not in good health? Come on out with me on the campaign trail," Sanders quipped at the event last week.

Pressed on whether he plans to release more medical records, Sanders responded: "I don't think we will."

The Bloomberg campaign released a letter from the candidate's doctor in December that said the former New York mayor was in "outstanding health" with no medical conditions that would prevent him from serving as president. The billionaire underwent a stent placement in 2000 for a blocked artery, according to that letter, which was also written by Sisson at Johns Hopkins University.

Bloomberg has undergone annual cardiac stress testing since the stent placement and his 2019 test was "normal and demonstrated excellent exercise tolerance," according to the letter. It also stated that Bloomberg takes blood thinners, beta-blockers and cholesterol medication, and that he had developed atrial fibrillation "in the setting of otherwise normal heart function" in 2018.

In a presidential debate hosted by NBC last week, Sanders -- asked about his past promise to release full medical records -- pointed to Bloomberg.

"I think the one area maybe that Mayor Bloomberg and I share -- you have two stents, as well," Sanders said.

Bloomberg responded: "25 years ago."

"Well, we both have two stents," Sanders said. "It's a procedure that is done about a million times a year."

Former South Bend, Indiana, Mayor Pete Buttigieg weighed in to say he was dissatisfied with Sanders' answer.

"Transparency matters, especially living through the Trump era. Now, under President Obama, the standard was that the president would release full medical records, do a physical, and release the readout," Buttigieg, the youngest candidate running for president, said. "I think that's the standard that we should hold ourselves to, as well."