Heart Failure Monitoring Research Articles

Predictors of heart failure events detected by a multisensor implantable defibrillator algorithm

Abstract Funding Acknowledgements Type of funding sources: None. Background Cardiovascular and non-cardiovascular comorbidities are common in heart failure (HF) patients and determine disease severity and prognosis. Select modern implantable defibrillators (ICDs) are equipped with multisensor algorithms for HF monitoring. The HeartLogic index combines multiple ICD-based sensor data (heart rate, heart sounds, thoracic impedance, respiration, activity), and the associated alert has proved to be a sensitive and timely predictor of impending HF decompensation in cardiac resynchronization therapy (CRT) patients. Purpose This analysis aims to investigate the performance of the algorithm in non-CRT patients, as well as in relation to the presence of comorbidities. Methods The HeartLogic feature was activated in 568 ICD patients (410 with CRT) from 26 centers. The median follow-up was 25 months [25th–75th percentile: 15-35]. Results We recorded 1200 HeartLogic alerts (0.71 alerts per patient-year) in 370 patients. Among patient characteristics, atrial fibrillation (AF) at implantation (HR: 1.62, 95%CI: 1.27-2.07, p<0.001) and chronic kidney disease (CKD) (HR: 1.53, 95%CI: 1.21-1.93, p<0.001) independently predicted alerts. HeartLogic alerts were not associated with CRT vs. non-CRT device implantation (HR: 1.03, 95%CI: 0.82-1.30, p=0.775). Comparing the combined index and all physiologic parameters during clinically stable periods we did not notice differences between CRT and non-CRT patients. Thoracic impedance was significantly lower in CKD than non-CKD patients. (46±11ohm versus 49±10ohm; p=0.047). We found a higher S3 amplitude (0.9±0.3mG versus 0.8±0.2mG; p=0.005) and nocturnal heart rate (72±9bpm versus 66±7bpm; p<0.001), and lower S1 amplitude (2.0±0.8mG versus 2.4±0.9mG; p<0.001) in AF patients vs non-AF. These differences persisted at the time of alerts (all p<0.05). In the overall population, and in patients stratified by device type, CKD and AF, we measured significant changes of all contributing sensors (paired t-test; p<0.05) from clinically stable periods to the time of alert. Conclusions The burden of HeartLogic alerts appears similar between CRT and non-CRT patients, while patients with AF and CKD seem more exposed to alerts. ICD-measured thoracic impedance is sensitive to the fluid overload that characterizes kidney disease, as well as the first and third heart sound amplitudes seem sensitive to the reduced ventricular efficiency during AF. Nonetheless, ICD sensors seem to equally contribute to the HeartLogic alerts in all patient subgroups.

PO-662-08 IMPLANTABLE DEFIBRILLATOR-DETECTED HEART FAILURE STATUS PREDICTS ATRIAL FIBRILLATION OCCURRENCE

In heart failure (HF) patients, atrial fibrillation (AF) is a common comorbidity and is associated with a worse prognosis. Implantable defibrillator (ICD) diagnostics allow continuous monitoring of atrial high-rate events (AHRE), as a surrogate of AF, and are equipped with algorithms for HF monitoring.

Using Machine Learning for Early Prediction of Cardiogenic Shock in Patients With Acute Heart Failure.

Despite technological and treatment advancements over the past 2​decades, cardiogenic shock (CS) mortality has remained between 40% and 60%. Our objective was to develop an algorithm that can continuously monitor heart failure patients and partition them into cohorts of high and low risk for CS. We retrospectively studied 24,461 patients hospitalized with acute decompensated heart failure, 265 of whom developed CS, in the Johns Hopkins Health System. Our cohort identification approach is based on logistic regression and makes use of vital signs, lab values, and medication administrations recorded during the normal course of care. Our algorithm identified patients at high risk of CS. Patients in the high-risk cohort had 10.2 times (95% confidence interval, 6.1-17.2) higher prevalence of CSthan those in the low-risk cohort. Patients who experienced CS while in the high-risk cohort were first deemed high risk a median of 1.7​days (interquartile range, 0.8-4.6) before CS diagnosis was made by their clinical team. To evaluate actionability, we randomly selected 50 patients designated as high risk who did develop CS and 50 who did not. On review of true positive cases, from the time of model identification as high risk to the eventual diagnosis of CS, 12% of patients had possible inappropriate therapy, and for 50% of patients, more tailored therapy options existed. On review of the false positive cases, 44% of cases were considered at high risk of CS or end-stage cardiomyopathy by their clinical teams or went onto develop other types of shock. This risk model was able to predict patients at higher risk of CS in a time frame that allowed a change in clinical care. The actionability evaluation demonstrates a possible opportunity to intervene as part of a CS algorithm for escalation of care.

Novel Approaches to Imaging the Pulmonary Vasculature and Right Heart.

There is an increased appreciation for the importance of the right heart and pulmonary circulation in several disease states across the spectrum of pulmonary hypertension and left heart failure. However, assessment of the structure and function of the right heart and pulmonary circulation can be challenging, due to the complex geometry of the right ventricle, comorbid pulmonary airways and parenchymal disease, and the overlap of hemodynamic abnormalities with left heart failure. Several new and evolving imaging modalities interrogate the right heart and pulmonary circulation with greater diagnostic precision. Echocardiographic approaches such as speckle-tracking and 3-dimensional imaging provide detailed assessments of regional systolic and diastolic function and volumetric assessments. Magnetic resonance approaches can provide high-resolution views of cardiac structure/function, tissue characterization, and perfusion through the pulmonary vasculature. Molecular imaging with positron emission tomography allows an assessment of specific pathobiologically relevant targets in the right heart and pulmonary circulation. Machine learning analysis of high-resolution computed tomographic lung scans permits quantitative morphometry of the lung circulation without intravenous contrast. Inhaled magnetic resonance imaging probes, such as hyperpolarized 129Xe magnetic resonance imaging, report on pulmonary gas exchange and pulmonary capillary hemodynamics. These approaches provide important information on right ventricular structure and function along with perfusion through the pulmonary circulation. At this time, the majority of these developing technologies have yet to be clinically validated, with few studies demonstrating the utility of these imaging biomarkers for diagnosis or monitoring disease. These technologies hold promise for earlier diagnosis and noninvasive monitoring of right heart failure and pulmonary hypertension that will aid in preclinical studies, enhance patient selection and provide surrogate end points in clinical trials, and ultimately improve bedside care.

Usefulness of telemedicine-based heart failure monitoring according to ‘eHealth literacy’ domains: Insights from the iCOR randomized controlled trial

BackgroundThe potential positive effect of electronic health (eHealth)-based heart failure (HF) monitoring remains uncertain mainly in the ‘low literacy’ or ‘computer or digital illiterate’ patients. The aim of this study was to determine the effectiveness of a telemedicine (TM)-based managed care solution across literacy levels and information and communications technology (ICT) skills. MethodsWe performed a sub-analysis on the basis of two literacy domains encompassed in the definition of ‘eHealth literacy’ to the HF-patients included in the ‘insuficiència Cardíaca Optimització Remota’ (iCOR) randomized study comparing TM vs. usual care (UC) in HF-patients. The primary study endpoint was the incidence of a non-fatal HF event after 6 months of inclusion. The event rates of primary and secondary study endpoints were calculated for each literacy domains and its combination. Cox proportional-hazards regression models were used to evaluate the effect of ‘eHealth literacy’ dimensions, treatment group and the interaction term ‘eHealth literacy’ domains by treatment group on study endpoints. ResultsThe beneficial effect of TM compared to UC strategy was consistent across all literacy domains (p-value for interaction 0.207 and 0.117 respectively). The risk of experiencing a primary event was significantly lower in patients that underwent allocation to the TM arm compared to UC in both clustered in the ‘lower literacy’ (p-value=0.001) and those allocated to the ‘lower ICT skills’ (p-value=0.001) subgroup. ConclusionsNon-invasive eHealth-based HF monitoring tools are effective compared to UC in preventing HF events in the early post-discharge period, regardless of two ‘eHealth literacy’ domains (‘traditional and computer literacy’).

Rising Pulmonary Artery Pressures Precede Hospitalizations For Heart Failure But Not For Other Causes During Ambulatory Hemodynamic Monitoring For Chronic Heart Failure

<h3>Introduction</h3> In patients with previous heart failure hospitalization (HFH), ambulatory hemodynamic monitoring reduced HFH by 57% in the CardioMEMS Post-Approval Study (PAS), which translated into a 27% reduction in all-cause hospitalization but no change in other causes of hospitalization. We compared the trajectories of pulmonary artery pressures (PAP) before and after breakthrough HFH and the non-HF hospitalizations (non-HFH) that occurred during chronic PAP monitoring. <h3>Methods</h3> The PAS was a single arm study of 1200 patients with NYHA 3 HF (all EF) and prior HFH within 12 months who underwent implantation of a CardioMEMS PA sensor. An independent clinical events committee adjudicated all hospitalizations with primary cause HF and non-HF. We analyzed PAP changes during the 6 weeks prior and 1 week following hospitalization for all pts with PAP data through the 7 weeks, excluding overlapping analysis periods. <h3>Results</h3> Analysis was available for 751 hospitalizations, only 199 (26.5%) were HFH and 552 were (73.5%) were non-HFH. The rising trajectory of PAP changes in advance of HFH was distinct from non-HFH with an increase in pressure from baseline beginning approximately 4 weeks prior to HFH and a decrease in pressure observed immediately after HFH but no change observed before or after non-HFH. <h3>Conclusion</h3> Among patients with chronic HF across a range of EF, PAP rise approximately 4 weeks in advance of HFH and fall by 7 days after, but do not change around non-HFH. These data demonstrate the consistent physiology of rising PAP for breakthrough HFH that occur despite hemodynamic monitoring and the stability of PAP without elevation around the more common hospitalizations for other causes.

Heartlogic Heart Failure Index As Covid Index: Predicting Severity Of Covid-19 In Patients With Advanced Heart Failure

Heart Logic heart failure diagnostic is a personalized, remote heart failure diagnostic and monitoring system using multiple, novel physiologic sensors. It has been proven to have high sensitivity and low-alert burden that combines sensor data into one composite index that provides weeks of advance notice for detecting early signs of worsening heart failure. We present two cases, one with non-ischemic cardiomyopathy, the other with ischemic cardiomyopathy. In both cases, patients had reduced ejection fraction status post cardiac resynchronization therapy defibrillator who were monitored with Heart Logic heart failure diagnostics. In the first case, a rapid increase in sensors alarmed us for impending exacerbation of heart failure and retrospective analysis of differentials led us to diagnosis of COVID-19. The patient developed increase in respiratory rate, mean heart rate and S3 component of heart sound while decrease in thoracic impedance, ultimately with increased Index. Patient was admitted, intubated and successfully recovered. Heart Logic Index helped us making the diagnosis in early stage of COVID-19 and manage effectively. We present another case of ischemic cardiomyopathy with reduced ejection fraction awaiting heart transplant due to severe multi vessel coronary artery disease who tested positive for COVID-19 with milder symptoms. He was monitored prospectively to assess changes in Heart Failure Index which remained normal correlating with the milder symptoms from COVID-19 itself. All the indices including S1, S3, respiratory rate and mean heart rate remained normal. Patient recovered without any major residual effects from COVID 19. Hence, heartlogic index could serve as proactive alert tool like a “COVID index” to suspect, correlate with severity of symptoms and monitor the outcome in patients of heart failure diagnosed with COVID-19.

Point-of-care NT-proBNP monitoring for heart failure: observational feasibility study in primary care.

Around one million individuals in the UK have heart failure (HF), a chronic disease that causes significant morbidity and mortality. N-terminal pro-B-type natriuretic peptide (NT-proBNP) monitoring could help improve the care of patients with HF in the community. The aim of this study is to provide evidence to support the routine use of point-of-care (POC) NT-proBNP monitoring in primary care. In this observational cohort study, the Roche Cobas h 232 POC device was used to measure NT-proBNP in 27 patients with HF at 0, 6, and 12 months, with a subset reanalysed in the laboratory for comparison. Data were analysed for within-person and between-person variability and concordance with laboratory readings using Passing-Bablok regression. GPs reported whether POC results impacted clinical decisionmaking, and patients indicated their willingness to participate in long-term cohort studies using the Likert acceptability scale. Within-person variability in POC NT-proBNP over 12 months was 881 pg/mL (95% confidence interval [CI] = 380 to 1382 pg/mL). Between-person variability was 1972 pg/mL (95% CI = 1,525 to 2791 pg/mL). Passing-Bablok regression showed no significant systematic difference between POC and laboratory measurements. Patients indicated a high level of acceptability, and GP decisionmaking was affected for at least one visit in a third of patients. Within-person variability in POC NT-proBNP is around half of between-person variability, so detecting changes could be of use in HF management. High patient acceptability and impact on clinical decisionmaking warrant further investigation in a larger long-term cohort study.

The GUIDE-HF trial of pulmonary artery pressure monitoring in heart failure: impact of the COVID-19 pandemic.

AimsDuring the coronavirus disease 2019 (COVID-19) pandemic, important changes in heart failure (HF) event rates have been widely reported, but few data address potential causes for these changes; several possibilities were examined in the GUIDE-HF study.Methods and resultsFrom 15 March 2018 to 20 December 2019, patients were randomized to haemodynamic-guided management (treatment) vs. control for 12 months, with a primary endpoint of all-cause mortality plus HF events. Pre-COVID-19, the primary endpoint rate was 0.553 vs. 0.682 events/patient-year in the treatment vs. control group [hazard ratio (HR) 0.81, P = 0.049]. Treatment difference was no longer evident during COVID-19 (HR 1.11, P = 0.526), with a 21% decrease in the control group (0.536 events/patient-year) and no change in the treatment group (0.597 events/patient-year). Data reflecting provider-, disease-, and patient-dependent factors that might change the primary endpoint rate during COVID-19 were examined. Subject contact frequency was similar in the treatment vs. control group before and during COVID-19. During COVID-19, the monthly rate of medication changes fell 19.2% in the treatment vs. 10.7% in the control group to levels not different between groups (P = 0.362). COVID-19 was infrequent and not different between groups. Pulmonary artery pressure area under the curve decreased −98 mmHg-days in the treatment group vs. −100 mmHg-days in the controls (P = 0.867). Patient compliance with the study protocol was maintained during COVID-19 in both groups.ConclusionDuring COVID-19, the primary event rate decreased in the controls and remained low in the treatment group, resulting in an effacement of group differences that were present pre-COVID-19. These outcomes did not result from changes in provider- or disease-dependent factors; pulmonary artery pressure decreased despite fewer medication changes, suggesting that patient-dependent factors played an important role in these outcomes. Clinical Trials.gov: NCT03387813Key questionsWhat factors explain the loss of treatment effect and reduction in heart failure events during COVID-19?Key findingsThe treatment effect change was not due to COVID-19-related events. Patient management was sustained but not intensified during COVID-19. Patient status improved during COVID-19 and pulmonary artery pressure reduced in both groups.Take home messagePatient behaviour probably improved during COVID-19, given that patient status and pulmonary artery pressure improved during COVID-19 despite fewer medication changes and without increased contact from providers.

Relevance of the Spectral Analysis Method of Tilted Fiber Bragg Grating-Based Biosensors: A Case-Study for Heart Failure Monitoring.

Optical fiber technology has rapidly progressed over the years, providing valuable benefits for biosensing purposes such as sensor miniaturization and the possibility for remote and real-time monitoring. In particular, tilted fiber Bragg gratings (TFBGs) are extremely sensitive to refractive index variations taking place on their surface. The present work comprises a case-study on the impact of different methods of analysis applied to decode spectral variations of bare and plasmonic TFBGs during the detection of N-terminal B-type natriuretic peptide (NT-proBNP), a heart failure biomarker, namely by following the most sensitive mode, peaks of the spectral envelopes, and the envelopes’ crossing point and area. Tracking the lower envelope resulted in the lowest limits of detection (LOD) for bare and plasmonic TFBGs, namely, 0.75 ng/mL and 0.19 ng/mL, respectively. This work demonstrates the importance of the analysis method on the outcome results, which is crucial to attain the most reliable and sensitive method with lower LOD sensors. Furthermore, it makes the scientific community aware to take careful attention when comparing the performance of different biosensors in which different analysis methods were used.

Comparison of clinical symptoms and bioimpedance to pulmonary capillary wedge pressure in heart failure

IntroductionClinical symptoms of heart failure commonly include fatigue, edema, and shortness of breath. Unfortunately, clinical monitoring has proven unreliable in predicting congestion and the need for hospitalization. Biosensing wearables have been developed as a potential adjunct to clinical signs and symptoms to detect congestion before it becomes severe thus preventing a heart failure hospitalization. HypothesisClinical signs and symptoms of heart failure will correlate with thoracic bioimpedance measurements (ZOE®) and pulmonary capillary wedge pressure (PCWP). MethodsOne hundred and fifty-five subjects undergoing right heart catheterization (RHC) were prospectively enrolled. A Zo value (ohms) was obtained, jugular venous pressure (JVP) was estimated, edema graded, and shortness of breath (SOB) assessed in all subjects. RHC was performed by a scheduled cardiologist per routine. One-way ANOVA was performed to assess the relationship between variables. A Pearson correlation coefficient was used to compare the Zo value and PCWP. ResultsNeither estimated JVP (cmH2O) (p = 0.65, n = 110) nor edema scores (p = 0.12, n = 110) demonstrated a significant relationship to PCWP. The presence of subjective SOB also did not demonstrate a significant association with PCWP (p = 0.99, n = 110). There was no correlation between ZOE® and PCWP (r = −0.08, p = 0.56, n = 56). ConclusionsThese findings support the idea that traditional measures for monitoring heart failure patients are limited.

Patient Perspectives on Home-Based Care and Remote Monitoring in Heart Failure: A Qualitative Study.

As individual interventions, home-based care and remote monitoring have been shown to help prevent hospitalizations for those with heart failure (HF) although both interventions have been limited by scalability and technical constraints, respectively. Few qualitative studies have explored patient perspectives, including acceptability, barriers, and facilitators of HF care inclusive of both interventions. The objective of this study is to explore patient perceptions on HF management at home, the use of home-based remote monitoring, and the value of home-based care. Qualitative interviews (N = 27) were conducted via phone (12/2020-3/2021) with adults with HF. A framework analysis was used to identify main themes along with verbatim transcription for coding and analyses. There were 5 key interview domains: general HF knowledge, perceptions of the value of home-based care, unmet needs related to the social determinants of health (SDOH), experience with healthcare technology and remote monitoring, and challenges in HF home management. Five major themes emerged. Patients reported: (1) home-based care plan instructions are understood; (2) following medication, diet, and fluid management instructions are challenging due to difficult adherence to and implementation at home; (3) financial limitations serve as barriers to acquiring healthy food; (4) home-based support is a valuable component of managing medications, diet, and fluid; (5) despite limited use of technology, strong willingness to use remote monitoring is present amongst most. Participants reported understanding of care plan instructions and challenges adhering to care plans at home. Barriers included needing more home-based support for medications, diet, and fluid management and requiring additional assistance with financial barriers related to unmet social needs. A combined intervention inclusive of remote monitoring and home-based support has potential to improve home-based strategies and clinical outcomes for HF patients.

Haemodynamic monitoring in acute heart failure - what you need to know.

Acute heart failure (AHF) is a sudden, life-threatening condition, defined as a gradual or rapid onset of symptoms and/or signs of HF. AHF requires urgent medical attention, being the most frequent cause of unplanned hospital admission in patients above 65 years of age. AHF is associated with a 4–12% in-hospital mortality rate and a 21–35% 1-year mortality rate post-discharge. Considering the serious prognosis in AHF patients, it is very important to understand the mechanisms and haemodynamic status in an individual AHF patient, thus preventing end-organ failure and death. Haemodynamic monitoring is a serial assessment of cardiovascular function, intended to detect physiologic abnormalities at the earliest stages, determine which interventions could be most effective, and provide the basis for initiating the most appropriate therapy and evaluate its effects. Over the past decades, haemodynamic monitoring techniques have evolved greatly. Nowadays, they range from very invasive to non-invasive, from intermittent to continuous, and in terms of the provided parameters. Invasive techniques contain pulmonary artery catheterization and transpulmonary thermodilution. Minimally invasive techniques include oesophageal Doppler and noncalibrated pulse wave analysis. Non-invasive techniques contain echocardiography, bioimpedance, and bioreactance techniques as well as non-invasive pulse contour methods. Each of these techniques has specific indications and limitations. In this article, we aimed to provide a pathophysiological explanation of the physical terms and parameters used for haemodynamic monitoring in AHF and to summarize the working principles, advantages, and disadvantages of the currently used methods of haemodynamic monitoring.

Feasibility and First Results of Heart Failure Monitoring Using the Wearable Cardioverter-Defibrillator in Newly Diagnosed Heart Failure with Reduced Ejection Fraction.

The wearable cardioverter–defibrillator (WCD) is used in patients with newly diagnosed heart failure and reduced ejection fraction (HFrEF). In addition to arrhythmic events, the WCD provides near-continuous telemetric heart failure monitoring. The purpose of this study was to evaluate the clinical relevance of additionally recorded parameters, such as heart rate or step count. We included patients with newly diagnosed HFrEF prescribed with a WCD. Via the WCD, step count and heart rate were acquired, and an approximate for heart rate variability (HRV5) was calculated. Multivariate analysis was performed to analyze predictors for an improvement in left ventricular ejection fraction (LVEF). Two hundred and seventy-six patients (31.9% female) were included. Mean LVEF was 25.3 ± 8.5%. Between the first and last seven days of usage, median heart rate fell significantly (p < 0.001), while median step count and HRV5 significantly increased (p < 0.001). In a multivariate analysis, a delta of HRV5 > 23 ms was an independent predictor for LVEF improvement of ≥10% between prescription and 3-month follow-up. Patients with newly diagnosed HFrEF showed significant changes in heart rate, step count, and HRV5 between the beginning and end of WCD prescription time. HRV5 was an independent predictor for LVEF improvement and could serve as an early indicator of treatment response.

Remote invasive monitoring of pulmonary artery pressures in heart failure patients: Initial experience in Portugal in the context of the Covid-19 pandemic

BackgroundDecompensated heart failure (HF) is associated with poor short- and long-term prognosis. Remote invasive monitoring of pulmonary artery pressures (PAP) enables early detection of HF decompensation before symptoms occur and may improve clinical outcomes. We aimed to describe our initial experience with the use of the CardioMEMS™ remote monitoring system in patients with HF, including its safety and effectiveness. Methods and resultsFive patients with HF in New York Heart Association class III and at least one hospitalization due to decompensated HF in last 12 months, who underwent invasive remote monitoring of PAP, were included in this prospective registry. The median age was 66.0 years (interquartile range [IQR] 50.5-77.5 years), 80.0% were men and all had HF with reduced ejection fraction. The pulmonary artery (PA) sensor was placed in a left PA branch in all patients and no major procedural complications occurred. In median follow-up of 40 days (IQR 40-61 days), a total of 271 pressure readings were transmitted, patient compliance was 100% and freedom from sensor failure 98.1%. In three patients, PAP remained within the goal during follow-up. Two patients presented an increase in PAP to values above the targets, despite the absence of symptom worsening. These required dietary and diuretic dose adjustment, without the need for outpatient clinic visits, which reduced PAP. No hospitalizations for HF or deaths occurred during follow-up. ConclusionHemodynamic-guided HF monitoring was safe and effective and may be a useful adjunctive tool to the standard-of-care management in selected HF patients, particularly in the context of the COVID-19 pandemic, where a reduction in the number of health care visits may be desirable.

Abstract 12455: Comparison of Clinical Symptoms and Bioimpedance to Pulmonary Capillary Wedge Pressure in Heart Failure

Introduction: Clinical symptoms of heart failure commonly include fatigue, edema, and shortness of breath. Unfortunately, clinical monitoring has proven to be unreliable for the assessment of congestion and predicting the need for hospitalization. Biosensing wearables have been developed as a potential adjunct to clinical signs and symptoms. Hypothesis: This report hypothesis a correlation between clinicians’ signs and symptoms of heart failure along with bioimpedance measurements (ZOE ® ), and pulmonary capillary wedge pressure (PCWP). Methods: One hundred and fifty-five subjects undergoing right heart catheterization (RHC) at Vanderbilt University Medical Center (VUMC) were prospectively enrolled. A Zo value (ohms) was obtained, jugular venous pressure (JVP) was estimated, edema graded, and dyspnea assessed in all subjects. RHC was performed by scheduled cardiologist per routine. One-way ANOVA was performed to assess relationship between dependent and independent variables. A Pearson correlation coefficient was used to compare Zo value and PCWP. Results: Neither estimated JVP (cmH 2 O) (p = 0.65, n=110) nor edema scores (p = 0.12, n=110) demonstrated a significant relationship to PCWP (Figure 1). The presence of subjective SOB also did not demonstrate significant association with PCWP (p = 0.99, n=110; Figure 1). There was no correlation between ZOE ® and PCWP (r = -0.08, p = 0.56, n=56; Figure 2). Conclusions: These findings support the idea that traditional measures for monitoring heart failure patients are limited.

Letter to the editor to update the article "Remote monitoring for heart failure using implantable devices: a systematic review, meta-analysis, and meta-regression of randomized controlled trials".

Our recently published systematic review and meta-analysis of heart failure (HF) remote monitoring using implantable devices (Hajduczok et al. in HF Reviews 1–20, 1) has been updated to reflected new data from the GUIDE-HF trial (Lindenfeld et al. in Lancet 398(10304):991-1001, 2). Data from randomized controlled trials (RCTs) was assessed to determine the effectiveness of implantable remote monitoring on the improvement of outcomes in HF patients. With the inclusion of the data from 1000 patients followed for 12 months in GUIDE-HF, our conclusions remain unchanged: Compared to standard of care, remote monitoring using implantable devices did not reduce mortality, CV, or HF hospitalizations. However, right ventricular/pulmonary pressure monitoring may reduce HF hospitalizations.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10741-021-10190-x.

Self-Powered Wearable Cardiac Stethoscope for Real-Time Monitoring Heart Failure

Heart failure has a high rate of morbidity and mortality, and the number of the patients all over the world has dramatically increased in recent years. Continuous and long-term cardiac monitoring is particularly important for early diagnosis and prevention. In this work, a new self-powered wearable cardiac stethoscope based on piezoelectric effect of PVDF film for real-time monitoring heart failure has been realized. The device can be easily attached to the skin and convert tiny vibration of human organs into electric signals without any external power supply (powered by the mechanical energy of the organ activity). By Fourier transform analysis, the piezoelectric output of the device can indicate the physiological status information of heart. Meanwhile, the sensing capabilities of the device is investigated on different parts of the body and the volunteers with different ages. The stethoscope achieves high sensitivity, real-time monitoring, and mechanical stability. This self-powered wearable cardiac stethoscope can broaden the application scenarios of the nanogenerators and promote the development of medical science and healthcare industry.

Load Distribution Analysis for Weight and Ballistocardiogram Measurements of Heart Failure Patients using a Bed Scale.

Ballistocardiogram (BCG) is an emerging tool with the potential to monitor heart failure (HF) patients. A close association of the weight to the BCG as an intermediate signal source requires a careful design, where events such as saturation of the weight signal can result in the loss of the BCG. This work closely examined the factors around the weight while load cells placed under each support of a bed collected the BCG (e.g., body weight, distribution over the four supports of the bed). Following the calibration of weights based on the location of the polls, the study examined the ratios of loads in head-foot and lateral directions. The head-foot ratio was also correlated to the height. Twelve non-obese HF patients were recruited, and the weight and BCG were appropriately measured, where the average error of the weight measurements was 0.45 ± 0.30%. The mean ratio of the loads between head to foot sensors was 3.2 ± 0.7 with a maximum ratio of 4.5, showing that the head-ward sensors supported greater body weight. The ratio of the loads between the right to left sensors was 1.2 ± 0.1. The height and the head-to-foot ratio had an inverse correlation (r = 0.52). Based on the analysis, the head-ward sensors should have a higher capacity of up to three times that of the foot-ward sensors to prevent any signal saturation. Mobility issues were observed in some subjects, attributing to the lateral imbalance. These novel findings based on the end-users (i.e., HF population) may allow better allocation of conditioning resources to obtain the BCG (e.g., optimally adjusted sensitivity).

Objective determination of peripheral edema in heart failure patients using short-wave infrared molecular chemical imaging.

.Significance: Peripheral pitting edema is a clinician-administered measure for grading edema. Peripheral edema is graded 0, , , , or , but subjectivity is a major limitation of this technique. A pilot clinical study for short-wave infrared (SWIR) molecular chemical imaging (MCI) effectiveness as an objective, non-contact quantitative peripheral edema measure is underway.Aim: We explore if SWIR MCI can differentiate populations with and without peripheral edema. Further, we evaluate the technology for correctly stratifying subjects with peripheral edema.Approach: SWIR MCI of shins from healthy subjects and heart failure (HF) patients was performed. Partial least squares discriminant analysis (PLS-DA) was used to discriminate the two populations. PLS regression (PLSR) was applied to assess the ability of MCI to grade edema.Results: Average spectra from edema exhibited higher water absorption than non-edema spectra. SWIR MCI differentiated healthy volunteers from a population representing all pitting edema grades with 97.1% accuracy ( shins). Additionally, SWIR MCI correctly classified shin pitting edema levels in patients with 81.6% accuracy.Conclusions: Our study successfully achieved the two primary endpoints. Application of SWIR MCI to monitor patients while actively receiving HF treatment is necessary to validate SWIR MCI as an HF monitoring technology.