Baseline and decline in device-derived activity level predict risk of death and heart failure in patients with an ICD for primary prevention

Recent Advances in the Wearable Devices for Monitoring and Management of Heart Failure

Heart failure (HF) is an acute and degenerative condition with high morbidity and mortality rates. Early diagnosis and treatment of HF can significantly enhance patient outcomes through admission and readmission reduction and improve quality of life. Being a progressive condition, the continuous monitoring of vital signs and symptoms of HF patients to identify any deterioration and to customize treatment regimens can be beneficial to the management of this disease. Recent breakthroughs in wearable technology have revolutionized the landscape of HF management. Despite the potential benefits, the integration of wearable devices into HF management requires careful consideration of technical, clinical, and ethical challenges, such as performance, regulatory requirements and data privacy. This review summarizes the current evidence on the role of wearable devices in heart failure monitoring and management, and discusses the challenges and opportunities in the field.

Cardiac implantable device interrogation in left ventricular systolic dysfunction reveals physiologic abnormalities prior to symptom onset in COVID-19: a case series

Background

COVID-19 has affected individuals across the globe, and those with cardiac implantable electronic devices (CIEDs) likely represent a high-risk group. These devices can be interrogated to reveal information about the patient activity, heart rate parameters, and respiratory rate.

Case summary

Four patients with CIEDs and left ventricular dysfunction were admitted to a single institution for COVID-19 infection. Each patient survived hospitalization, and none required intensive care. Retrospectively, CIED interrogation revealed each patient had decreased activity level prior to their reporting COVID-19 symptoms. Similarly, respiratory rate increased before symptom onset for three of the patients, while one did not have these data available. Of the three patients with heart rate variability (HRV) available, two had decreased HRV before they developed symptoms. After hospital discharge, these parameters returned to their baseline.

Discussion

This case series suggests physiologic changes identifiable through interrogation of CIEDs may occur prior to the reported onset of COVID-19 symptoms. These data may provide objective evidence on which to base more sensitive assessments of infectious risk when performing contact tracing in communities.

Accelerometer-assessed physical behavior and the association with clinical outcomes in implantable cardioverter-defibrillator recipients: A systematic review

Background

Current implantable cardioverter-defibrillator (ICD) devices are equipped with a device-embedded accelerometer capable of capturing physical activity (PA). In contrast, wearable accelerometer-based methods enable the measurement of physical behavior (PB) that encompasses not only PA but also sleep behavior, sedentary time, and rest-activity patterns.

Objective

This systematic review evaluates accelerometer-based methods used in patients carrying an ICD or at high risk of sudden cardiac death.

Methods

Papers were identified via the OVID MEDLINE and OVID EMBASE databases. PB could be assessed using a wearable accelerometer or an embedded accelerometer in the ICD.

Results

A total of 52 papers were deemed appropriate for this review. Out of these studies, 30 examined device-embedded accelerometry (189,811 patients), 19 examined wearable accelerometry (1601 patients), and 3 validated wearable accelerometry against device-embedded accelerometry (106 patients). The main findings were that a low level of PA after implantation of the ICD and a decline in PA were both associated with an increased risk of mortality, heart failure hospitalization, and appropriate ICD shock. Second, PA was affected by cardiac factors (eg, onset of atrial fibrillation, ICD shocks) and noncardiac factors (eg, seasonal differences, societal factors).

Conclusion

This review demonstrated the potential of accelerometer-measured PA as a marker of clinical deterioration and ventricular arrhythmias. Notwithstanding that the evidence of PB assessed using wearable accelerometry was limited, there seems to be potential for accelerometers to improve early warning systems and facilitate preventative and proactive strategies.