Bloomberg releases heart health data, says Sanders should do the same

Mike Bloomberg released new information on his heart health Thursday and called on his rival Bernie Sanders to do so as well.

Why it matters: The development, first reported by CNN, continues a public feud between the two candidates, both of whom are 78 years old. The move appears to be an attempt by Bloomberg to make Sanders' health a central issue in the Democratic contest.

Flashback: The senator from Vermont underwent a medical procedure after suffering a heart attack last year.

Details: The former New York City mayor's annual health exam last July included cardiac stress testing and a stress echocardiogram, per a letter from Johns Hopkins University physician Stephen Sisson.

• The results showed Bloomberg's left ventricular ejection fraction at 60–65%, his left ventricular cavity size and left ventricular function were described as "normal," and his exercise capacity was "excellent," according to Sisson.
• Between the lines: Ejection fractions measure "how much blood the left ventricle pumps out with each contraction," per the American Heart Association. A normal ejection fraction is between 50 and 70.

What they're saying: "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," Bloomberg campaign spokesperson Stu Loeser told Axios. "Mike Bloomberg's doctor shared Mike's number. Will Senator Sanders ask his doctor to do the same?"

• A spokesperson for Sanders told CNN the campaign already released documents related to the candidate's overall health. Sanders publicly shared letters from his primary physician and two cardiologists last December.

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