After the plane crash, Mark was able to say goodbye to the love of his life, Lexie, for the last time. He was heartbroken, both literally and figuratively. What he and the others didn't know right away was that Mark had sustained a Cardiac Tamponade after impact. Meredith does what she can with the items at hand to keep Mark alive, but just barely. Later everyone was rescued and Mark was placed on life support. Even on these machine, there was no saving Mark. Callie and Derek were by his side as the ventilator was removed and Mark slowly passed. R.I.P. Mark Sloan.