In an example, a medical device includes a physiological data monitor (PDM), a memory, and a processor. The PDM is configured to monitor a physiological data parameter. The memory circuit is configured to store data collected by the PDM. The processor is configured to detect a data capture event and capture a first segment of physiological data associated with the data capture event. The processor is also configured to determine an amount of memory storage space available and determine a first priority level for the first segment of physiological data. The processor is further configured to determine a second priority level for a second segment of physiological data stored previously and select a processing scheme using the first and second priority levels. Finally, the processor is configured to process, using the processing scheme, the first and second segments of physiological data and store the first segment of physiological data.