David E. Ritscher

A Detector for a Chronic Implantable Atrial Tachyarrhythmia Monitor

Continuous long-term monitoring of atrial fibrillation (AF) and tachycardia (AT) is an unmet clinical need, which could be met with a chronically-implanted monitor. Improved therapeutic decisions based on accurate monitoring of parameters, such as daily AF/AT burden (hours/ day) may lead to improvements in clinical outcomes such as reduction in hospitalizations, symptoms, and strokes. This paper describes an AF/AT detector that detects AF as well as AT with an irregular ventricular response, and a supplementary AT detector for AT with more regular ventricular response. Seven databases with significant durations of AF, AT, and sinus rhythm were used to evaluate the performance of the detectors. All patient records with AF (N = 124) were detected by the AF/AT detector to have AF/AT burden with a mean, median, and 75 percentile of absolute error in burden detection of 8.8, 0, and 4 min, respectively. In patients having AF burden (ges 10 min), the AF/AT detector was found to have burden accuracy within 20% of true burden in 96% of patients. The specificity was 94%, defined as follows: in patient records without AF/AT (N = 174), the percentage with AF/AT burden les10 min in the 24-h recordings. The AF/AT detector underestimates AT burden, thus degrading performance, in patients with significant amounts of AT with more regular ventricular response. The supplementary AT detector reduces the underestimation of AT while overestimating burden in patients without a significant amount of AT. The detectors described here could be implemented in an implantable monitor for accurate long-term AF/AT monitoring.

Management of atrial tachyarrhythmias

The prevalence of cardiovascular diseases such as atrial tachyarrhythmias (ATa) has become prevalent worldwide. A discussion on the detection, monitoring, termination, and prevention of ATa is presented. Rhythm control is defined as maintenance of sinus rhythm. One measure of rhythm control is the percent of time spent in atrial tachyarrhythmias, commonly referred to as ATa burden. Rhythm control can be attempted with antiarrhythmic drugs, atrial ablation, or implantable devices. This paper gives attention to the management of ATa using implantable devices. Such devices must detect ATa accurately and either prevent them from recurring or terminate them by using electrical stimulation techniques