Publications

While cardiorespiratory fitness is strongly associated with mortality and diverse outcomes, routine measurement is limited. We used smartphone-derived physical activity data to estimate fitness among 50 older adults. We recruited iPhone owners undergoing cardiac stress testing and collected recent iPhone physical activity data. Cardiorespiratory fitness was measured as peak metabolic equivalents of task (METs) achieved on cardiac stress test. We then estimated peak METs using multivariable regression models incorporating iPhone physical activity data, and validated with bootstrapping. Individual smartphone variables most significantly correlated with peak METs (p-values both < 0.001) included daily peak gait speed averaged over the preceding 30 days (r = 0.63) and root mean square of the successive differences of daily distance averaged over 365 days (r = 0.57). The best-performing multivariable regression model included the latter variable, as well as age and body mass index. This model explained 68% of variability in observed METs (95% CI 46%, 81%), and estimated peak METs with a bootstrapped mean absolute error of 1.28 METs (95% CI 0.98, 1.60). Our model using smartphone physical activity estimated cardiorespiratory fitness with high performance. Our results suggest larger, independent samples might yield estimates accurate and precise for risk stratification and disease prognostication.

California has focused on health equity in the state's COVID-19 reopening plan. The Blueprint for a Safer Economy assigns each of California's 58 counties into 1 of 4 tiers based on 2 metrics: test positivity rate and adjusted case rate. To advance to the next less-restrictive tier, counties must meet that tier's test positivity and adjusted case rate thresholds. In addition, counties must have a plan for targeted investments within disadvantaged communities, and counties with more than 106 000 residents must meet an equity metric. California's explicit incorporation of health equity into its reopening plan underscores the interrelated fate of its residents during the COVID-19 pandemic and creates incentives for action. This article evaluates the benefits and challenges of this novel health equity focus, and outlines recommendations for other US states to address disparities in their reopening plans.

The use of remote monitoring technology for cardiovascular electronic implantable devices has grown significantly in recent decades, yet several key questions remain about its integration into clinical care. We performed semi-structured interviews of patients, clinicians, and device clinic technicians involved in clinical remote monitoring of cardiovascular implantable devices at our institution. Twenty-eight interviews comprised of 15 patients and 13 clinicians were conducted from October 2019 through February 2020. Interview transcripts were analyzed using a mixed inductive and deductive approach. Perspectives among clinicians and patients varied regarding familiarity, educational experiences, and preferences regarding how remote monitoring data are handled. Three key domains emerged including knowledge and understanding, managing alerts, and cost transparency. Within these domains, key findings includedvery limited understanding of how remote monitoring functions and how alerts in particular are handled. These knowledge deficits (both patients and providers) appeared to arise in part from different equipment and platforms among manufacturers, the complexity of the technology, and lack of formalized education in remote monitoring. However, interviewees expressed generally high levels of trust in the technology and care systems supporting remote monitoring. Few respondents described concerns around cybersecurity, but patients in particular did raise concerns about cost transparency and frequent billing. In conclusion, conflicting perceptions around remote monitoring persist and indicate important knowledge gaps despite high trust in the care pathway. This qualitative analysis offers insight into patient and clinician understanding of and attitudes toward remote monitoring, and may guide future efforts to improve education and patient-centeredness of remote monitoring.

Cardiovascular implantable electronic device (CIED) infections are morbid, costly, and difficult to manage. This review explores the pathophysiology, diagnosis, and management of CIED infections. Diagnostic accuracy has been improved through increased awareness and improved imaging strategies. Pocket or bloodstream infection with virulent organisms often requires complete system extraction. Emerging prophylactic interventions and novel devices have expanded preventative strategies and options for re-implantation. A clear and nuanced understanding of CIED infection is important to the practicing electrophysiologist.