Remote at-home detection and monitoring of functional chronotropic incompetence in heart failure patients.

Chronotropic incompetence (CI) is common in heart failure (HF) patients and is associated with worsening outcome. Detecting and tracking functional CI during activities of daily living could provide insight into its contribution to HF symptoms and facilitate effective HF patient management. HF patients (n = 180, NYHA Class III/IV, ejection fraction (EF) ≤40%) were enrolled in a multi-center prospective monitoring study and had an external multi-sensor system applied to the chest and replaced weekly during a 90-day study. Medical information was collected at baseline and study close. Heart rate, respiration, activity, and body fluid data from the system were transmitted at regular intervals and used for offline analysis. Patients were primarily male (70%), with 61 ± 13 years mean age, 25 ± 5 kg/m(2) BMI, and 28 ± 7% EF. By correlating age-adjusted activity level and heart rate adaptation with a proprietary algorithm, functional CI was detected in 45% and ruled out in 29% of patients under conditions of daily living. In the remaining patients (26%), functional CI assessment was indeterminate due to insufficient age-adjusted activity level. Functional CI and No-CI groups were not significantly different in terms of baseline demographics, characteristics or HF outcome over the study period. β-blocker use was 16% in the CI group and 82% in the no-CI group (p < 0.001), and therefore, could not explain the manifestation of functional CI. This proof-of-concept study suggests that a chronotropic response that may be functionally debilitating during activities of daily living in HF patients can be detected and tracked in a point-of-care telemonitoring approach using a non-invasive, adherent device.