An active noise cancellation device (2) for a medical device includes an active circuit having a first input connection (8), a second input connection (10), and an output connection (12). The second input connection (10) is connected to at least one predetermined reference signal. The active noise cancellation device (2) further includes a low-impedance body connection electrode (4) adapted to be in electrical contact with a bloodstream of a subject, wherein the low-impedance body connection electrode (4) is connected to said first input connection (8), and a feedback branch (14) connecting the output connection (12) with the first input connection (8). The feedback branch (14) comprises a current limiting circuit (18) to limit a current through said feedback branch (14) to be lower than a predetermined current.
