Getting at least one dose of the Pfizer vaccine increased the risk of a rare type of heart inflammation, especially in young males, according to a large new study from researchers in Israel. However, the diagnosed cases were usually mild, and most of the patients were sent home without ongoing need for treatment. … Researchers identified 54 cases of myocarditis among more than 2.5 million people ages 16 years and older who got at least one dose of the Pfizer vaccine. All but three of them occurred in males. Ages were from 21 to 35, with a median of 27.