Systems and methods for detecting atrial tachyarrhythmia

A system for detecting cardiac arrhythmia in a patient, comprising:

• an ambulatory medical device including a communication circuit and circuitry configured to sense a cardiac electrical signal from the patient, to detect a ventricular rate parameter for the patient using the sensed cardiac electrical signal, and to detect an atrial fibrillation (AF) event using the detected ventricular rate parameter;
• and
• an external system communicatively coupled to the ambulatory medical device, the external system including:
• an arrhythmia detector circuit configured to:
• determine an ensemble average of multiple segments of the sensed cardiac electrical signal corresponding to a plurality of cardiac cycles and to generate a signal characteristic of a P wave for the plurality of cardiac cycles using the determined ensemble average;
• and
• determine an AF confidence indicator indicating a confidence level of the detected AF event based on the ventricular rate parameter of the detected AF event and the signal characteristic of the P wave for the plurality of cardiac cycles comprising the detected AF event;
• an event prioritizer circuit configured to generate an event priority for the detected AF event based on the AF confidence indicator;
• and
• a controller circuit configured to dynamically control allocation of resources of the ambulatory medical device to process or store information about the detected AF event, in accordance with the generated event priority, including increasing allocation of ambulatory medical device resources in response to the generated event priority indicating a high confidence or a numerical confidence score above a threshold in contrast to the generated event priority indicating a low confidence or the numerical confidence score below the threshold,
• wherein to detect the AF event comprises using information of the cardiac electrical signal separate from the detected absence or presence of the P wave.

A method for detecting cardiac arrhythmia in a patient using a medical-device system, comprising:

• receiving a cardiac electrical signal sensed from the patient;
• determining a ventricular rate parameter for the patient using the received cardiac electrical signal;
• detecting, using an arrhythmia detector circuit, an atrial fibrillation (AF) event using the determined ventricular rate parameter;
• detecting, using the arrhythmia detector circuit, a signal characteristic of a P wave from an ensemble average of multiple segments of the received cardiac electrical signal corresponding to a plurality of cardiac cycles;
• determining an AF confidence indicator indicating a confidence level of the detected AF event based on the ventricular rate parameter of the detected AF event and the signal characteristic of the P wave for the plurality of cardiac cycles comprising the detected AF event;
• receiving the detected AF event in a time-based order corresponding to a time of the detected AF event;
• generating, using an event prioritizer circuit, an event priority for the detected AF event based on the AF confidence indicator, the event priority different than the time-based order;
• and
• via a controller circuit, dynamically allocating resources of the medical-device system to process or store information about the AF event, in accordance with the generated event priority, including increasing allocation of resources in response to the generated event priority indicating a high confidence or a numerical confidence score above a threshold in contrast to the generated event priority indicating a low confidence or the numerical confidence score below the threshold,
• wherein detecting the AF event comprises using information of the cardiac electrical signal separate from the detected absence or presence of the P wave.