Association of a device-based remote management heart failure pathway with outcomes: TriageHF Plus real-world evaluation.

AIMS: Clinical pathways have been shown to improve outcomes in patients with heart failure (HF). Although patients with HF often have a cardiac implantable electronic device, few studies have reported the utility of device-derived risk scores to augment and organize care. TriageHF Plus is a device-based HF clinical pathway (DHFP) that uses remote monitoring alerts to trigger structured telephone assessment for HF stability and optimization. We aimed to evaluate the impact of TriageHF Plus on hospitalizations and describe the associated workforce burden. METHODS AND RESULTS: TriageHF Plus was a multi-site, prospective study that compared outcomes for patients recruited between April 2019 and February 2021. All alert-triggered assessments were analysed to determine the appropriateness of the alert and the workload burden. A negative-binomial regression with inverse probability treatment weighting using a time-matched usual care cohort was applied to estimate the effect of TriageHF Plus on non-elective hospitalizations. A post hoc pre-COVID-19 sensitivity analysis was also performed. The TriageHF Plus cohort (n = 443) had a mean age of 68.8 ± 11.2 years, 77% male (usual care cohort: n = 315, mean age of 66.2 ± 14.5 years, 65% male). In the TriageHF Plus cohort, an acute medical issue was identified following an alert in 79/182 (43%) cases. Fifty assessments indicated acute HF, requiring clinical action in 44 cases. At 30 day follow-up, 39/66 (59%) of initially symptomatic patients reported improvement, and 20 (19%) initially asymptomatic patients had developed new symptoms. On average, each assessment took 10 min. The TriageHF Plus group had a 58% lower rate of hospitalizations across full follow-up [incidence relative ratio: 0.42, 95% confidence interval (CI): 0.23-0.76, P = 0.004]. Across the pre-COVID-19 window, hospitalizations were 31% lower (0.69, 95% CI: 0.46-1.04, P = 0.077). CONCLUSIONS: These data represent the largest real-world evaluation of a DHFP based on multi-parametric risk stratification. The TriageHF Plus clinical pathway was associated with an improvement in HF symptoms and reduced all-cause hospitalizations.

A Patient-Centered Intervention Reduces Disparities in Remote Monitoring in Patients With Implanted Cardiac Devices.

BACKGROUND: Remote monitoring (RM) is recommended for patients with cardiovascular implantable electronic devices, yet many individuals, especially those living in underserved communities, fail to receive this guideline-directed care. Multilevel interventions that target patient and clinic-level barriers to RM care may be beneficial. OBJECTIVES: This study sought to evaluate a remotely delivered, patient-centered intervention to improve RM activation and adherence and reduce disparities in RM care. METHODS: The intervention provides home delivery of remote monitor, phone-based education, monitor setup, and facilitation of first transmission. A retrospective cohort analysis was performed using RM data from 190,643 patients (71.6 ± 12.7 years of age, 40.5% female) implanted with a pacemaker or defibrillator at 4,195 U.S. clinics between October 2015 and October 2019. Outcomes included RM activation (12 weeks and 1-year postimplantation) and adherence to clinic-scheduled transmissions. Patients receiving a cardiovascular implantable electronic deviceimplant 0 to 730 days before (control group, n = 95,861) and after (intervention group, n = 94,782) intervention launch were compared using logistic regression and generalized estimating equations. Multivariable models included patient, clinic, and neighborhood socioeconomic characteristics. RESULTS: The odds of achieving guideline-recommended activation were significantly higher in the intervention group at 12 weeks (OR: 2.99; 76.7% vs 60.9%; P < 0.001) and 1 year (OR: 3.05; 88.2% vs 79.3%; P < 0.001). Adherence to scheduled transmissions was also higher in the intervention group compared with the control group (OR: 2.18; 89.1% vs 81.9%; P < 0.001). Preintervention disparities in RM activation and adherence were reduced in underserved groups following the intervention. CONCLUSIONS: A remotely delivered patient-centered intervention was associated with earlier activation and improved adherence to RM while reducing disparities in RM care.

Cost-effectiveness of an insertable cardiac monitor in a high-risk population in the US.

BACKGROUND: Insertable cardiac monitors (ICMs) are a clinically effective means of detecting atrial fibrillation (AF) in high-risk patients, and guiding the initiation of non-vitamin K oral anticoagulants (NOACs). Their cost-effectiveness from a US clinical payer perspective is not yet known. The objective of this study was to evaluate the cost-effectiveness of ICMs compared to standard of care (SoC) for detecting AF in patients at high risk of stroke (CHADS2 ≥ 2), in the US. METHODS: Using patient data from the REVEAL AF trial (n = 393, average CHADS2 score = 2.9), a Markov model estimated the lifetime costs and benefits of detecting AF with an ICM or with SoC (specifically intermittent use of electrocardiograms and 24-h Holter monitors). Ischemic and hemorrhagic strokes, intra- and extra-cranial hemorrhages, and minor bleeds were modelled. Diagnostic and device costs, costs of treating stroke and bleeding events and medical therapy-specifically costs of NOACs were included. Costs and health outcomes, measured as quality-adjusted life years (QALYs), were discounted at 3% per annum, in line with standard practice in the US setting. One-way deterministic and probabilistic sensitivity analyses (PSA) were undertaken. RESULTS: Lifetime per-patient cost for ICM was $31,116 versus $25,330 for SoC. ICMs generated a total of 7.75 QALYs versus 7.59 for SoC, with 34 fewer strokes projected per 1000 patients. The model estimates a number needed to treat of 29 per stroke avoided. The incremental cost-effectiveness ratio was $35,528 per QALY gained. ICMs were cost-effective in 75% of PSA simulations, using a $50,000 per QALY threshold, and a 100% probability of being cost-effective at a WTP threshold of $150,000 per QALY. CONCLUSIONS: The use of ICMs to identify AF in a high-risk population is likely to be cost-effective in the US healthcare setting.

Clinic Time Required for Remote and In-Person Management of Patients With Cardiac Devices: Time and Motion Workflow Evaluation.

BACKGROUND: The number of patients with cardiac implantable electronic device (CIED) is increasing, creating a substantial workload for device clinics. OBJECTIVE: This study aims to characterize the workflow and quantify clinic staff time requirements for managing patients with CIEDs. METHODS: A time and motion workflow evaluation was performed in 11 US and European CIEDs clinics. Workflow tasks were repeatedly timed during 1 business week of observation at each clinic; these observations included all device models and manufacturers. The mean cumulative staff time required to review a remote device transmission and an in-person clinic visit were calculated, including all necessary clinical and administrative tasks. The annual staff time to manage a patient with a CIED was modeled using CIED transmission volumes, clinical guidelines, and the published literature. RESULTS: A total of 276 in-person clinic visits and 2173 remote monitoring activities were observed. Mean staff time required per remote transmission ranged from 9.4 to 13.5 minutes for therapeutic devices (pacemaker, implantable cardioverter-defibrillator, and cardiac resynchronization therapy) and from 11.3 to 12.9 minutes for diagnostic devices such as insertable cardiac monitors (ICMs). Mean staff time per in-person visit ranged from 37.8 to 51.0 and from 39.9 to 45.8 minutes for therapeutic devices and ICMs, respectively. Including all remote and in-person follow-ups, the estimated annual time to manage a patient with a CIED ranged from 1.6 to 2.4 hours for therapeutic devices and from 7.7 to 9.3 hours for ICMs. CONCLUSIONS: The CIED patient management workflow is complex and requires significant staff time. Understanding process steps and time requirements informs the implementation of efficiency improvements, including remote solutions. Future research should examine heterogeneity in patient management processes to identify the most efficient workflow.

Prevalence and Economic Burden of Malnutrition Diagnosis Among Patients Presenting to United States Emergency Departments.

BACKGROUND: Malnutrition is a potentially remediable condition that when untreated contributes to poor health and economic outcomes. While assessment of malnutrition risk is improving, its identification rate and economic burden in emergency departments (EDs) is largely unknown. We sought to determine prevalence and economic burden of diagnosed malnutrition among patients presenting to U.S. EDs. METHODS: This is a retrospective analysis of Healthcare Cost and Utilization Project Nationwide Emergency Department Sample data. Malnutrition prevalence was confirmed via International Classification of Diseases, 9th Edition, diagnosis codes. The economic burden was assessed by comparing probability of hospitalization and the average total charges between propensity-score matched visits with and without a malnutrition diagnosis. RESULTS: Data from 238 million ED visits between 2006 and 2014 were analyzed. Over this period, the prevalence of diagnosed malnutrition increased for all demographic categories assessed. For older adults (≥65 years), the prevalence increased from 2.5% (2006) to 3.6% (2014). Older age, high-income community residence, Western region, urban areas, and Medicare coverage were associated with higher diagnosis prevalence. Malnutrition diagnosis was associated with a 4.23 (95% confidence interval [CI] = 3.93 to 4.55) times higher odds of hospitalization and $21,892 higher mean total charges (95% CI = $19,593 to $24,192). CONCLUSIONS: While malnutrition is currently diagnosed at a low rate in U.S. EDs, the economic burden of malnutrition is substantial in this care setting. Given the potential for systematic malnutrition screening and treatment protocols to alleviate this burden, future research is warranted.

Budget Impact Analysis of a Home-Based Nutrition Program for Adults at Risk for Malnutrition.

BACKGROUND: Hospital-based, nutrition-focused interventions have significantly lowered the cost-associated burden of poor nutrition through a reduction in healthcare resource utilization (HCRU). However, for patients at risk for poor nutrition who receive nutritional care at home, limited evidence exists on the economic impact of nutrition-focused interventions. OBJECTIVE: To estimate the 30-day cost-savings associated with an at-home nutrition-focused quality improvement program in the postacute care setting for patients at risk for poor nutrition from the perspective of a hospital system. METHODS: We compared the HCRU of 1546 patients enrolled in a quality improvement program during 1 year versus 7413 patients in a pre-program historical cohort who received care during the 1 year before the quality improvement program implementation. The analysis included the number of 30-day hospitalizations, emergency department and outpatient visits for both cohorts, and the associated costs. The main analysis included the fixed and variable costs for the program, and the costs of oral nutritional supplement and delivery. The costs for hospitalization, emergency department, and outpatient visit costs were based on the 2013 Healthcare Cost and Utilization Project and Medical Expenditure Panel Survey. RESULTS: Based on the 2013 survey, the baseline costs for hospitalization, emergency department, and outpatient visit costs were $18,296, $1312, and $535, respectively. Our health economic analysis about the 30-day overall HCRU has shown that the quality improvement program group resulted in a total cost-savings of $2,408,668 for the 1546 patients in the program and a net savings of $1558 per patient compared with the costs for the pre-quality improvement program historical cohort. CONCLUSION: The use of a nutrition-focused quality improvement program led to significant 30-day cost-savings, by reducing HCRU for adults who received nutritional-based care at home. The improvements in HCRU highlight the importance of implementing nutrition-focused quality improvement programs for hospital systems that provide care for patients who are at risk for poor nutrition across a variety of care settings.

Similar health economic outcomes in low-risk and high-risk malnourished inpatients as screened by the Malnutrition Screening Tool after delivery of oral nutritional supplements.

OBJECTIVE: The aim of this study was to determine whether modified low- and high-risk Malnutrition Screening Tool (MST) scores (2 versus >2, respectively) were independently predictive of health economic outcomes. METHODS: We analyzed data from a recent nutrition-based quality improvement program (QIP) that prescribed daily oral nutritional supplements for all hospitalized adults at risk for malnutrition. In the original study, an electronic medical records-based MST was administered at the time of admission, and patients were classified as "low risk" or "high risk" for malnutrition based on MST scores (2 versus ≥2). We compared health economic outcomes for patients at low or high risk for malnutrition based on a modified score (MST = 2 versus >2, respectively), looking for between-group differences in length of stay (LOS) and unplanned 30-d readmissions. Analyses were additionally stratified by age (<65 versus ≥65 y of age). RESULTS: Of the 1269 patients enrolled in the QIP, 413 (32.5%) had MST of 2 and 856 (67.5%) had MST >2. Mean LOS was 5.19 d (±4.78) for patients with MST 2 and 4.49 d (±4.69) with MST >2 (non-statistically significant between-group difference; P = 0.277). There were no significant differences in unplanned 30-d readmission rates (14% for low-risk and 17.1% for high-risk patients; P = 0.171). These findings remained statistically insignificant when the low- and high-risk MST score groups were further stratified by age. CONCLUSIONS: Outcomes of hospitalized patients with MST 2 were not significantly different from those with an MST >2. This suggests that patients at both lower and higher risk for malnutrition (based on MST scores of 2 versus ≥3) were similar in terms of LOS and 30-d readmission rates. To avoid overlooking cases of malnutrition risk, the validated cutoff scores for the MST should be consistently implemented. Training that is consistent with the validated MST is recommended rather than attempting to reduce the case burden by "raising the bar" and attempting to classify patients with an MST = 2 as "low risk."

Anatomic correlates of deep brain stimulation electrode impedance.

BACKGROUND: The location of the optimal target for deep brain stimulation (DBS) of the subthalamic nucleus (STN) remains controversial. Electrode impedance affects tissue activation by DBS and has been found to vary by contact number, but no studies have examined association between impedance and anatomic location. OBJECTIVES: To evaluate the relationship between electrode impedance and anatomic contact location, and to assess the clinical significance of impedance. METHODS: We gathered retrospective impedance data from 101 electrodes in 73 patients with Parkinson's disease. We determined contact location using microelectrode recording (MER) and high-field 7T MRI, and assessed the relationship between impedance and contact location. RESULTS: For contact location as assessed via MER, impedance was significantly higher for contacts in STN, at baseline (111 Ω vs STN border, p=0.03; 169 Ω vs white matter, p<0.001) and over time (90 Ω vs STN border, p<0.001; 54 Ω vs white matter, p<0.001). Over time, impedance was lowest in contacts situated at STN border (p=0.03). Impedance did not vary by contact location as assessed via imaging. Location determination was 75% consistent between MER and imaging. Impedance was inversely related to absolute symptom reduction during stimulation (-2.5 motor portion of the Unified Parkinson's Disease Rating Scale (mUPDRS) points per 1000 Ω, p=0.01). CONCLUSIONS: In the vicinity of DBS electrodes chronically implanted in STN, impedance is lower at the rostral STN border and in white matter, than in STN. This finding suggests that current reaches white matter fibres more readily than neuronal cell bodies in STN, which may help explain anatomic variation in stimulation efficacy.

Clinical implications of local field potentials for understanding and treating movement disorders.

BACKGROUND: Deep brain stimulation (DBS) for the treatment of movement disorders has provided researchers with an opportunity to record electrical oscillatory activity from electrodes implanted in deep brain structures. Extracellular activity recorded from a population of neurons, termed local field potentials (LFPs), has shed light on the pathophysiology of movement disorders and holds the potential to lead to refinement in existing treatments. OBJECTIVE: This paper reviews the clinical significance of LFPs recorded from macroelectrodes implanted in basal ganglia and thalamic targets for the treatment of Parkinson's disease, essential tremor and dystonia. METHODS: Neural population dynamics and subthreshold events, which are undetectable by single-unit recordings, can be examined with frequency band analysis of LFPs (frequency range: 1-250 Hz). RESULTS: Of clinical relevance, reliable correlations between motor symptoms and components of the LFP power spectrum suggest that LFPs may serve as a biomarker for movement disorders. In particular, Parkinson's rigidity has been shown to correlate with the power of beta oscillations (13-30 Hz), and essential tremor coheres with oscillations of 8-27 Hz. Furthermore, evidence indicates that the optimal contacts for DBS programming can be predicted from the anatomic location of beta and gamma bands (48-200 Hz). CONCLUSION: LFP analysis has implications for improved electrode targeting and the development of a real-time, individualized, 'closed-loop' stimulation system.

Variation in deep brain stimulation electrode impedance over years following electrode implantation.

BACKGROUND: Deep brain stimulation (DBS) electrode impedance is a major determinant of current delivery to target tissues, but long-term variation in impedance has received little attention. OBJECTIVES: To assess the relationship between electrode impedance and time in a large DBS patient population and characterize the relationship between contact activity and impedance. METHODS: We collected retrospective impedance and programming data from 128 electrodes in 84 patients with Parkinson's disease, essential tremor or dystonia. Effects of time, contact activity, stimulation voltage and other parameters on impedance were assessed. We also examined impedance changes following contact activation and deactivation. RESULTS: Impedance decreased by 73 Ω/year (p < 0.001), with 72% of contacts following a downward trend. Impedance was on average 163 Ω lower in active contacts (p < 0.001). Contact activation and inactivation were associated with a more (p < 0.001) and less (p = 0.016) rapid decline in impedance, respectively. Higher stimulation voltages were associated with lower impedance values (p < 0.001). Contact number and electrode model were also significant predictors of impedance. CONCLUSIONS: Impedance decreases gradually in a stimulation-dependent manner. These trends have implications for long-term programming, the development of a closed-loop DBS device and current understanding of the electrode-tissue interface.

An international survey of deep brain stimulation procedural steps.

BACKGROUND: Deep brain stimulation (DBS) surgery is standard of care for the treatment of certain movement disorders. OBJECTIVE: We sought to characterize the spectrum of steps performed in DBS surgery, at centers around the world where this surgery is performed. METHODS: We identified the main steps in DBS surgery workflow and grouped these 19 steps into 3 phases (preoperative, operative, and postoperative). A survey tool, informed by a pilot survey, was administered internationally by trained study personnel at high- and low-volume DBS centers. Procedural components, duration, and surgeon motivational factors were assessed. Cluster analysis was used to identify procedural and behavioral clusters. RESULTS: One hundred eighty-five procedure workflow surveys (143 DBS centers) and 65 online surveys of surgeon motivational drivers were completed (45% response rate). Significant heterogeneity in technique, operative time, and surgeon motivational drivers was reported across centers. CONCLUSIONS: We provide a description of the procedural steps involved in DBS surgery and the duration of these steps, based on an international survey. These data will enable individual surgeons and centers to examine their own experience relative to colleagues at other centers and in other countries. Such information could also be useful in comparing efficiencies and identifying workflow obstacles between different hospital environments.

Long-term recordings of local field potentials from implanted deep brain stimulation electrodes.

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus is an effective treatment for Parkinson disease. However, DBS is not responsive to an individual's disease state, and programming parameters, once established, do not change to reflect disease state. Local field potentials (LFPs) recorded from DBS electrodes are being investigated as potential biomarkers for the Parkinson disease state. However, no patient data exist about what happens to LFPs over the lifetime of the implant. OBJECTIVE: We investigated whether LFP amplitude and response to limb movement differed between patients implanted acutely with subthalamic nucleus DBS electrodes and patients implanted 2 to 7 years previously. METHODS: We recorded LFPs at DBS surgery time (9 subjects), 3 weeks after initial placement (9 subjects), and 2 to 7 years (median: 3.5) later during implanted programmable generator replacement (11 sides). LFP power-frequency spectra for each of 3 bipolar electrode derivations of adjacent contacts were calculated over 5-minute resting and 30-second movement epochs. Monopolar impedance data were used to evaluate trends over time. RESULTS: There was no significant difference in ß-band LFP amplitude between initial electrode implantation (OR) and 3-week post-OR times (P=.94). However, ß-band amplitude was lower at implanted programmable generator replacement times than in OR (P=.008) and post-OR recordings (P=.039). Impedance measurements declined over time (P<.001). CONCLUSION: Postoperative LFP activity can be recorded years after DBS implantation and demonstrates a similar profile in response to movement as during acute recordings, although amplitude may decrease. These results support the feasibility of constructing a closed-loop, patient-responsive DBS device based on LFP activity.