Patent ID: 7890162

Claim:
A method of confirming that an EGM deflection represents an R-wave comprising: sensing an EGM via an implantable medical device (IMD); sensing an intracardiac pressure via the IMD; determining a dP/dt of the sensed intracardiac pressure; detecting an electrical event using the EGM; opening a time window after detecting the electrical event; determining a maximum positive dP/dt of the intracardiac pressure sensed during the open time window; detecting the presence of a mechanical event responsive to the maximum positive dP/dt being greater than a first threshold; and determining that the electrical event includes an R-wave responsive to the presence of the mechanical event; determining a minimum negative dP/dt of the intracardiac pressure sensed during the open time window; and detecting the presence of an oversensed T-wave or noise using the minimum negative dP/dt, the oversensed T-wave or noise being deemed present when the mechanical event is deemed absent and an absolute value of the minimum negative dP/dt is greater than a second threshold.