An implantable
medical device (IMD) (210) for managing therapy is provided that is couplable to a lead (220, 224) with an
electrode (222, 232), a memory (294) configured to store program instructions and one or more processors (260). The one or more processors (260) can be configured to execute the program instructions to determine a sensed
right atrium (RAs) event or a paced
right atrial (RAp) event (RAs,p event) (412), determine a sensed right
ventricle (RVs) event (414) by detecting a
cardiac activity (CA)
signal (402) reaches a threshold amplitude (410) and determine a
maximum amplitude (420) in a determined period of time (418) after the CA
signal (402) reaches the threshold amplitude (410), and determine an RAs,p-RVs interval (404) between the RAs,p event (412) and RVs event (414). The one or more processors (260) can also be configured to calculate an atrioventricular
delay (AV)
delay based on the RAs,p-RVs interval (404), and manage therapy, provided by the IMD (210), based on the
AV delay that is calculated.