Fold or Call

[AJdenmark]

Ok here is what i know about villan, he is very tight and usually comes back hard when he have something. He was i my oppenion the best of the opponents at the table.

Total number of players : 7
Seat 1: Hero (48312)
Seat 2: UTG +1 (73250)
Seat 4: MP (50987)
Seat 6: MP+1(42764)
Seat 7: Botten (17031)
Seat 9: SB (13179)
Seat 10: Villan (19665)
SB posts small blind (750)
Villan posts big blind (1500)
** Dealing down cards **
Dealt to Hero [ Ad, Th ]

Hero raises (4500) to 4500
UTG +1 folds.
MP folds.
MP +1 folds.
Botten folds.
SB folds.
Villan raises (18165) to 19665
Villan is all-In.

What to do?