liver - hepatology, heart - ?

CARDIOLOGY
List of words for the clue liver - hepatology, heart - ? from the crossword:
TEETH STOMATOLOGY NEUROLOGY BRAIN ORGAN ORGANS VITALS SOUL VEIN DONOR VISCUS AGE PATE FOIE BILE OIL IRON AMI AORTA
WordClue
OILcod-liver or mineral
RATEof exchange or heart
BRAINhepatology - liver, neurology - ?
HEARThepatology - liver, cardiology - ?
LIVERcardiology - heart, hepatology - ?
MEDALPurple Heart
TEETHhepatology - liver, stomatology - ?
ATRIUMpart of heart
BOWELScore, heart
BRAVERYheart
DARKNESSHeart of ... (Conrad)
HEPATITISinflammation of the liver tissue
NEUROLOGYliver - hepatology, brain - ?
VENTRICLEpart of heart
HEPATOLOGYheart - cardiology, liver - ?
PERICARDIUMpart of heart
STOMATOLOGYliver - hepatology, teeth - ?
NEUROLOGYliver - hepatology, brain - ?
STOMATOLOGYliver - hepatology, teeth - ?