Abstract: A wearable device for detecting heart rhythm abnormalities, comprising: a sensor unit comprising at least one pulse oximeter; a processor unit; a memory unit; and a power unit comprising a battery and configured to disseminate battery power amongst various components of the wearable device; wherein, the at least one pulse oximeter is configured to measure optically a bloodstream at a sampling rate and output first data; wherein, the processor unit is configured to process the first data and determine a time for the processed first data to be automatically recorded in the memory unit; wherein, the processor unit is configured to dynamically adjust the sampling rate of the at least one pulse oximeter based on a predetermined event; and wherein, the processor unit is configured to control the power unit in such a way that the sampling rate is dynamically adjusted through applying varying power levels to the sensor unit and consequently the wearable device is operable to enable a duration up to 90 days for a sing