Insights From HeartLogic Multisensor Monitoring During the COVID-19 Pandemic in New York City

In a recent issue of JACC: Heart Failure, DeFilippis et al. (1) and Abraham et al. (2) recommended increasing utilization of telemedicine and remote monitoring platforms for heart failure (HF) care amid the coronavirus disease-2019 (COVID-19) pandemic. To date, COVID-19 has claimed over 180,000 lives in the United States (3). Our group (4) and Almufleh et al. (5) recently showed effective remote pulmonary arterial (PA) pressure monitoring using the CardioMEMS platform (Abbott Laboratories, Plymouth, Minnesota) with a reduction in HF admissions during the peak of the pandemic in New York and Massachusetts, respectively. Widespread use of this technology is limited to patients with pre-existing implantation, prompting a query of other telemonitoring platforms. Boston Scientific’s widely available HeartLogic platform (Boston Scientific, Marlborough, Massachusetts) is a proprietary algorithm in their high-voltage cardiac implantable electronic devices and incorporates heart sounds, thoracic impedance, respirations, heart rate, and activity to provide integrated data that may allow for detection of early signs of worsening HF.

We examined whether the HeartLogic multiple sensor platform may elucidate behavioral changes that impact congestion and HF hospitalizations. A retrospective chart review and analysis of patients with HF and cardiac devices with HeartLogic was performed. Forty-five patients met criteria; however, 7 patients had devices implanted after February 2020 and were thus excluded. Of the 38 included patients, 22 (58%) had implantable cardioverter-defibrillators only, 15 (40%) had cardiac resynchronization therapy, and 1 patient had a pacemaker. Mean age was 60 ± 16 years, 76% were male, and the majority had New York Heart Association functional class II symptoms (Figure 1A ). Overall, there was no difference in median composite HeartLogic scores in the period before COVID-19 (February 1 to 29, 2020) or during the pandemic after implementation of stay-at-home orders (March 23 to April 15, 2020) (4.8 [interquartile range (IQR): 0.4 to 6.2] vs. 2.7 [IQR: 0.1 to 5.2]; p = 0.891). However, as the pandemic surged, we observed a significant drop in activity level (1.6 [IQR: 1.0 to 2.2] vs. 1.2 [IQR: 0.8 to 1.5]; p < 0.001), with a corresponding decrease in mean heart rate (75 beats/min vs. 73 beats/min; p = 0.004). We also observed small increases in thoracic impedance (44.6 [IQR: 39.0 to 49.3] vs. 45.5 [IQR: 39.7 to 50.3]; p = 0.007) and less frequent S3 (0.91 vs. 0.87; p = 0.001) (both potentially representing decreased pulmonary congestion). (Figure 1B). No significant trends were observed in other indices of the composite HeartLogic index. While sedentary behavior is often thought to lead to worsening HF, here decreased autonomic tone with less activity and potentially less frequent access to unhealthy food options may have resulted in less congestion; however, this remains a testable hypothesis. The generalizability of these observations is limited by small sample size and short follow-up. Three (7.9%) patients were hospitalized for HF during the study period, comparable to 4 (10.5%) patients in the 3 months prior to the outbreak.

Figure 1.

Clinical Characteristics and Mean Thoracic Impedance and Activity Levels of Patients During the COVID-19 Pandemic in New York City

(A) Clinical characteristics of the study population. Data are expressed as number (%), mean ± SD, or median (interquartile range), as appropriate. (B) Mean ± SD of thoracic impedance (blue) and activity level (red) before and after the first case of coronavirus disease-2019 (COVID-19) and after the stay-at-home policy in New York City. ACEi = angiotensin-converting enzyme inhibitor; ARB = angiotensin receptor blocker; ARNI = angiotensin receptor neprilysin inhibitor; HFrEF = heart failure with reduced ejection fraction; LVEF = left ventricular ejection fraction; NYHA = New York Heart Association.

Similar to others’ experiences, the COVID-19 pandemic has acted as a catalyst for our group to further leverage HeartLogic and CardioMEMS telemonitoring systems. Broadly, the evolving patterns of care required by the pandemic serve as a call to action to better implement, expand, and innovate remote monitoring platforms for HF. How outcomes will be impacted accordingly remains to be seen.