Abstract: An implantable medical device (IMD) is implanted in a patient. The IMD uses a plurality of electrode vectors to generate intrathoracic impedance measurements. The intrathoracic impedance measurements can be indicative of amounts of intrathoracic fluid in the patient. An accumulation of intrathoracic fluid may indicate that the patient is at an increased risk of experiencing a heart failure event in the near future. The IMD performs a vector selection operation on a recurring basis. When the IMD performs the vector selection operation, the IMD uses impedance measurements to select one of the electrode vectors. The IMD can perform a risk assessment operation on another recurring basis. During performance of the risk assessment operation, the IMD uses impedance measurements of the selected electrode vector and/or other patient characteristics stored within the IMD to determine whether the patient is at an increased risk of experiencing a heart failure event.

Abstract: A medical device and method for detecting and classifying cardiac rhythm episodes that includes a sensing module to sense cardiac events, a therapy delivery module, and a detection module configured to determine intervals between the sensed cardiac events, determine a predetermined cardiac episode is occurring in response to the determined intervals, determine whether a ventricular rate is greater than an atrial rate in response to the determined intervals, determine whether undersensing is occurring in response to the ventricular rate being greater than the atrial rate, perform a supraventricular tachycardia (SVT) discrimination analysis in response to undersensing occurring, and control the therapy delivery module to deliver therapy in response to the SVT discrimination analysis.

Abstract: A medical device and method for detecting and classifying cardiac rhythm episodes that includes a sensing module to sense cardiac events; a therapy delivery module, and a detection module configured to determine intervals between the sensed cardiac events, determine a predetermined cardiac episode is occurring in response to the determined intervals, determine whether a ventricular rate is greater than an atrial rate in response to the determined intervals, determine whether oversensing is occurring in response to the ventricular rate being greater than the atrial rate, adjust the determined intervals in response to oversensing occurring to generate an adjusted ventricular rate, determine whether the cardiac episode is occurring in response to the adjusted ventricular rate, perform a supraventricular tachycardia (SVT) discrimination analysis in response to the cardiac episode occurring in response to the adjusted ventricular rate, and control the therapy delivery module to deliver therapy in response to the S

Abstract: A medical device and method for detecting and classifying cardiac rhythm episodes that includes a sensing module to sense cardiac events; a therapy delivery module, and a detection module configured to determine intervals between the sensed cardiac events, determine a predetermined cardiac episode is occurring in response to the determined intervals, determine whether a ventricular rate is greater than an atrial rate in response to the determined intervals, determine whether oversensing is occurring in response to the ventricular rate being greater than the atrial rate, adjust the determined intervals in response to oversensing occurring to generate an adjusted ventricular rate, determine whether the cardiac episode is occurring in response to the adjusted ventricular rate, perform a supraventricular tachycardia (SVT) discrimination analysis in response to the cardiac episode occurring in response to the adjusted ventricular rate, and control the therapy delivery module to deliver therapy in response to the S

Abstract: A medical device and method for detecting and classifying cardiac rhythm episodes that includes a sensing module to sense cardiac events, a therapy delivery module, and a detection module configured to determine intervals between the sensed cardiac events, determine a predetermined cardiac episode is occurring in response to the determined intervals, determine whether a ventricular rate is greater than an atrial rate in response to the determined intervals, determine whether undersensing is occurring in response to the ventricular rate being greater than the atrial rate, perform a supraventricular tachycardia (SVT) discrimination analysis in response to undersensing occurring, and control the therapy delivery module to deliver therapy in response to the SVT discrimination analysis.