A device comprising: a sensor apparatus comprising a heart rate sensor to sense a heart rate of a heart failure patient; and a processing apparatus operably coupled to the sensor apparatus and comprising processing circuitry configured to: monitor a heart rate of the heart failure patient using the heart rate sensor during a plurality of heart rate recovery events, wherein each of the plurality of heart rate recovery events comprises a duration of time after an activity resulting in an elevated heart rate, determine heart rate recovery information based on the measured heart rate during each of the plurality of heart rate recovery events, and generate a trend of heart rate recovery information from the determined heart rate recovery information over the plurality of heart rate recovery events over a period of time; generate a cardiac status of the heart failure patient based on the generated trend of heart rate recovery information; and detect worsening heart failure in the heart failure patient based on the cardiac status; the device further comprising: a notification apparatus configured to notify the heart failure patient to initiate and terminate an activity resulting the elevated heart rate, wherein the sensing apparatus is configured to sense a heart rate at a termination of the activity and upon completion of the duration of time after the activity, and wherein the heart rate recovery information for each of the plurality of heart rate recovery events comprises a difference between the heart rate at the termination of the activity and the heart rate taken upon the completion of the duration of time after the activity. a sensor apparatus comprising a heart rate sensor to sense a heart rate of a heart failure patient; and a processing apparatus operably coupled to the sensor apparatus and comprising processing circuitry configured to: monitor a heart rate of the heart failure patient using the heart rate sensor during a plurality of heart rate recovery events, wherein each of the plurality of heart rate recovery events comprises a duration of time after an activity resulting in an elevated heart rate, determine heart rate recovery information based on the measured heart rate during each of the plurality of heart rate recovery events, and generate a trend of heart rate recovery information from the determined heart rate recovery information over the plurality of heart rate recovery events over a period of time; generate a cardiac status of the heart failure patient based on the generated trend of heart rate recovery information; and detect worsening heart failure in the heart failure patient based on the cardiac status; monitor a heart rate of the heart failure patient using the heart rate sensor during a plurality of heart rate recovery events, wherein each of the plurality of heart rate recovery events comprises a duration of time after an activity resulting in an elevated heart rate, determine heart rate recovery information based on the measured heart rate during each of the plurality of heart rate recovery events, and generate a trend of heart rate recovery information from the determined heart rate recovery information over the plurality of heart rate recovery events over a period of time; generate a cardiac status of the heart failure patient based on the generated trend of heart rate recovery information; and detect worsening heart failure in the heart failure patient based on the cardiac status; the device further comprising: a notification apparatus configured to notify the heart failure patient to initiate and terminate an activity resulting the elevated heart rate, wherein the sensing apparatus is configured to sense a heart rate at a termination of the activity and upon completion of the duration of time after the activity, and wherein the heart rate recovery information for each of the plurality of heart rate recovery events comprises a difference between the heart rate at the termination of the activity and the heart rate taken upon the completion of the duration of time after the activity. a notification apparatus configured to notify the heart failure patient to initiate and terminate an activity resulting the elevated heart rate, wherein the sensing apparatus is configured to sense a heart rate at a termination of the activity and upon completion of the duration of time after the activity, and wherein the heart rate recovery information for each of the plurality of heart rate recovery events comprises a difference between the heart rate at the termination of the activity and the heart rate taken upon the completion of the duration of time after the activity.