Subcutaneous electrocardiography monitor configured for self-optimizing ECG data compression

A subcutaneous electrocardiography monitor configured for self-optimizing ECG data compression, comprising:

• an implantable housing for implantation within a patient;
• a pair of electrocardiographic (ECG) sensing electrodes;
• electronic circuitry provided within the housing, the electronic circuitry comprising:
• an ECG front end circuit interfaced to a microcontroller and configured to sense electrocardiographic signals via the pair of the ECG sensing electrodes;
• a memory;
• a microcontroller operable to execute under modular micro program control as specified in firmware, the microcontroller configured to:
• obtain a series of electrode voltage values based on the sensed electrocardiographic signals;
• detect one or more portions of the electrode voltage series that comprise noise;
• represent the noise portions of the series with at least one symbol within a compression of the electrode voltage series;
• select one or more of a plurality of compression algorithms for compressing non-noise portions of the electrode voltage series;
• apply one or more of the selected compression algorithms to non-noise portions of the electrode voltage series;
• evaluate a degree of compression of the non-noise portions of the electrode voltage series achieved using the application of the selected algorithms, comprising one of:
• determine a randomness of the compressed non-noise portions and compare the randomness to a randomness threshold, wherein the evaluation of the degree of compression is performed based on the comparison to the randomness threshold;
• and
• determine a likelihood of further compression of the compressed non-noise portions, wherein the evaluation of the degree of compression is performed based on the likelihood;
• apply one or more of the compression algorithms to the compressed non-noise portions of the electrode voltage series based upon the evaluation of the degree of compression;
• and
• store the electrode voltage series compression, the electrode voltage series compression comprising the at least one symbol and the compressed non-noise portions of the electrode voltage series, within the memory.