Answer: hearttransplant

AnswerCrossword Clue
HEARTTRANSPLANTLouis Washkansky received the first one
HEARTTRANSPLANTMedical achievement of 1967
HEARTTRANSPLANT1967 medical milestone
HEARTTRANSPLANTHATER?
HEARTTRANSPLANTMajor medical achievement of 1967