The 24-year-old right-hander has been through heart ailments before. In 2011 after experiencing arrythmic episodes, he was forced to go on the DL. In Spring Training of 2012, he dealt with a rapid heartbeat.
Any ailment to the heart has to be taken seriously, and the Dodgers will proceed with extreme caution in the matter. From a baseball standpoint, Jansen's production will be sorely missed during a playoff push that has the Dodgers in a tight division race with the San Francisco Giants.
Jensen has a 2.57 ERA and 86 strikeouts in 56.2 innings pitched on the year.