A method and apparatus for monitoring a cardiovascular pressure signal in a medical device that includes comparing the sensed pressure signal to a first pressure threshold, identifying a first sense greater than the first pressure threshold, determining a metric of the pressure signal in response to the identified first sense, comparing the sensed pressure signal to a second pressure threshold not equal to the first pressure threshold in response to the identified first sense, identifying a second sense, subsequent to the first sense, greater than the second pressure threshold, identifying a third sense, subsequent to the first sense, greater than the first pressure threshold, and determining a cycle length corresponding to electrical activity of a heart in response to one of the first sense and the third sense or the second sense and the third sense.
