The New York Times questioned why 2020 Democratic presidential candidate Bernie Sanders was withholding key details about a recent health scare.

The 78-year-old Vermont senator temporarily suspended his campaign on Wednesday after undergoing a medical procedure to open up a blocked artery.

"During a campaign event yesterday evening, Sen. Sanders experienced some chest discomfort," his campaign said in a statement. "Following medical evaluation and testing he was found to have a blockage in one artery and two stents were successfully inserted. Sen. Sanders is conversing and in good spirits. He will be resting up over the next few days."

Veteran Times reporter and trained physician Lawrence K. Altman was critical of the aging socialist's handling of the issue. On Friday, he published an analysis piece titled, "Bernie Sanders Had a Common Heart Procedure. So Why the Mystery?" Altman wrote that the stent procedure Sanders went through is very common, making it "puzzling why he has not released more details." Sanders also has not released the results of blood and electrocardiogram tests that would show whether or not he had a heart attack, nor has he allowed reporters to interview his doctors.

"Doctors often release patients who undergo such procedures in a day or two," Altman wrote. "Mr. Sanders remains in the hospital, and his campaign has closely guarded pertinent details about his heart condition and treatment, raising questions about the extent of his health issues."

"The health questions hang over Mr. Sanders in part because he would become the nation’s oldest president by far if elected …" Altman said. "Mr. Sanders is a private person, no doubt, but most modern-day presidents and serious candidates for the presidency have put forward details to inform the electorate after emergency health issues."

Late Friday afternoon, hours after Altman's article, the Sanders campaign released additional details on the hospital stay. The physicians who treated him said he suffered a heart attack, although they used the term "myocardial infarction."

"The senator was stable upon arrival and taken immediately to the cardiac catheterization laboratory, at which time two stents were placed in a blocked coronary artery in a timely fashion," the doctors said. "All other arteries were normal."

They also called his time in the hospital "uneventful" and said he's making good progress.

Sanders released a doctor's evaluation during his 2016 presidential run, but has not done so in the 2020 primary. His previous evaluation showed he had been treated for gout, hypothyroidism, and skin tumors, but was in "overall very good health."

Updated: 6:35 p.m.: This was updated to include the statement from Sanders's campaign.