Methods, systems, and devices that estimate longevity of an implantable medical device

An external device, comprising:

• a telemetry subsystem configured to wirelessly communication with an implantable medical device (IMD) that is powered by a battery and implanted within a patient;
• a display;
• and
• at least one processor communicatively coupled to the telemetry subsystem and the display, the at least one processor configured to
• separate a range of capacity levels for the battery of the IMD, which said range extends from an initial capacity level (Qi) for the battery to a subsequent capacity level (Qt) for the battery, into a number (N) of separate intervals (int1, int2, . . . intN), such that for each interval, of the N intervals, a respective estimated current (IIMD) consumed by the IMD remains substantially constant during the interval
• wherein N is an integer that is equal to or greater than 3, and
• wherein for each interval of the N intervals, there is a respective beginning and end of the interval, and
• wherein for one or more of the N intervals, the respective estimated current (IIMD) consumed by the IMD during the interval differs from the estimated current consumed by the IMD during one or more other ones of the N intervals;
• determine, for each interval of the N intervals, an amount of time (Δt) that it is estimated to take for the battery to discharge from the beginning of the interval to the end of the interval, and thereby determine N amounts of time (Δtint1, Δtint2, . . . ΔtintN),
• sum the determined N amounts of time (Δtint1, Δtint2, . . . ΔtintN) to thereby determine an estimate of a total amount of time (TQi→Qf) that it takes to discharge the battery from the initial capacity level (Qi) to the subsequent capacity level (Qf), wherein the total amount of time (TQi→Qf) is indicative of a longevity of the IMD that is powered by the battery;
• and
• cause to be displayed, on the display, an indication of the estimate of the total amount of time (TQi→Qf) that it takes to discharge the battery from the initial capacity level (Qi) to the subsequent capacity level (Qf), which is indicative of the longevity of the IMD that is powered by the battery.

A method for use with an implantable medical device (IMD) that is powered by a battery, the method comprising:

• computing the following iterative equation
• Qn+1=Qn+IIMD(Vbatt(Qn))·Δt
• with Qn initialized with a specified initial capacity level (Qi) for the battery,
• where
• Qn is a specified capacity level for the battery that changes from one iteration of the iterative equation to a next iteration of the iterative equation,
• Δt is a specified duration of time that remains the same from one iteration of the iterative equation to a next iteration of the iterative equation,
• Vbatt(Qn) is a voltage of the battery at the capacity level Qn, and
• IIMD(Vbatt(Qn)) is a current consumed by the IMD as a function of the voltage of the battery at the capacity level Qn;
• repeating the iterative equation a plurality of times until Qn+1 reaches a specified subsequent capacity level (Qf) for the battery, to thereby determine a value for N, where N is how many iterations of the iterative equation are computed until Qn+1 reaches the specified subsequent capacity level (Qf) for the battery;
• wherein for one or more of the N iterations, the IIMD(Vbatt(Qn)), which is the respective current consumed by the IMD as a function of the voltage of the battery at the capacity level Qn, is different compared to the IIMD(Vbatt(Qn)) for one or more other ones of the N iterations;
• and
• determining a product of N multiplied by the specified duration of time (Δt) to thereby determine an estimate of a total amount of time (TQi→Qf) that it takes to discharge the battery from the initial capacity level (Qi) to the subsequent capacity level (Qf), wherein the total amount of time (TQi→Qf) is indicative of a longevity of the IMD that is powered by the battery.

An external device, comprising:

• a telemetry subsystem configured to wirelessly communication with an implantable medical device (IMD) that is powered by a battery and implanted within a patient;
• a display;
• and
• at least one processor communicatively coupled to the telemetry subsystem and the display, the at least one processor configured to
• compute the following iterative equation
• Qn+1=Qn+IIMD(Vbatt(Qn))·Δt
• with Qn initialized with a specified initial capacity level (Qi) for the battery,
• where
• Qn is a specified capacity level for the battery that changes from one iteration of the iterative equation to a next iteration of the iterative equation,
• Δt is a specified duration of time that remains the same from one iteration of the iterative equation to a next iteration of the iterative equation,
• Vbatt(Qn) is a voltage of the battery at the capacity level Qn,
• IIMD(Vbatt(Qn)) is a current consumed by the IMD as a function of the voltage of the battery at the capacity level Qn, and
• N is how many iterations of the iterative equation are computed until Qn+1 reaches the specified subsequent capacity level (Qf) for the battery;
• repeat the iterative equation a plurality of times until Qn+1 reaches a specified subsequent capacity level (Qf) for the battery, to thereby determine a value for N, where N is how many iterations of the iterative equation are computed until Qn+1 reaches the specified subsequent capacity level (Qf) for the battery;
• wherein for one or more of the N iterations, the IIMD(Vbatt(Qn)), which is the respective current consumed by the IMD as a function of the voltage of the battery at the capacity level Qn, is different compared to the IIMD(Vbatt(Qn) for one or more other ones of the N iterations;
• determine a product of N multiplied by the specified duration of time (Δt) to thereby determine an estimate of a total amount of time (TQi→Qf) that it takes to discharge the battery from the initial capacity level (Qi) to the subsequent capacity level (Qf), wherein the estimate of the total amount of time (TQi→Qf) is indicative of a longevity of the IMD that is powered by the battery;
• and
• cause to be displayed, on the display, an indication of the estimate of the total amount of time (TQi→Qf) that it takes to discharge the battery from the initial capacity level (Qi) to the subsequent capacity level (Qf), which is indicative of the longevity of the IMD that is powered by the battery.