Methods and devices that identify overdetection in implantable cardiac systems

Inventors

Allavatam, Venugopal • Warren, Jay A. • Sanghera, Rick

Assignees

Cameron Health Inc

Abstract

Methods, systems, and devices for signal analysis in an implantable cardiac device such as an implantable cardioverter defibrillator. In illustrative examples, captured data including detected events is analyzed to identify likely overdetection of cardiac events. Analysis of the apparent width of detected events is used to determine whether overdetection is occurring. If overdetection is identified, data may be modified to correct for overdetection, to reduce the impact of overdetection, or to ignore overdetected data.

Core Innovation

The invention relates to an implantable cardiac device that senses a signal with implanted electrodes and detects events from the sensed signal, where the detected events are separated by intervals. The device captures a series of detected events and characterizes the series as wide or narrow, identifies a qualifying narrow-wide-narrow sequence of detected events, and determines that the wide event of the qualifying narrow-wide-narrow sequence is an overdetected event.

To mitigate overdetection, the operational circuitry calculates a cardiac rate for the patient using intervals between detected events which are not determined to be overdetections. In broader embodiments, the operational circuitry analyzes detected events to develop a set of several characteristics, categorizes the detected events for each characteristic, and observes alternating categorizations across the characteristics.

The device combines categorizations from two separate characteristics to identify overdetections within the detected events using at least two characteristics that each show alternating categories in a predetermined manner. The set of characteristics can include correlation and detected event width, including correlation relative to a template, static correlation and dynamic correlation, as well as interval duration.

Further embodiments include using selected ones of the set of detected events to estimate a cardiac rate, after identifying that a particular one of the set of detected events likely resulted from overdetection using an alternating pattern from a first characteristic and reviewing a second characteristic to determine that the particular one of the set of detected events is not an overdetection notwithstanding the alternating pattern.

Claims Coverage

The partial content provides three independent claims. Across these claims, the inventive features focus on detecting and classifying event width, identifying alternating patterns, using additional event characteristics including correlation and interval duration, and determining overdetection so that cardiac rate is based on events not determined to be overdetections.

Across the independent claims, overdetections are identified by alternating patterns derived from event characterization and, in other embodiments, by combining alternating categorizations from at least two event characteristics such as correlation and interval duration, followed by estimating cardiac rate using detected events not determined to be overdetections.

Stated Advantages

Documented Applications

No documented applications found