Implantable Devices Research Articles

Impact of biological environment on bending fatigue lifetime in additive-manufactured polylactic acid fabricated by 3D-printing

Polylactic acid (PLA) has become desirable for biomedical applications, particularly implantable devices. However, the degradation of PLA in biological environments under mechanical stress remains incompletely understood and requires further investigation. This study compared the plain fatigue (PF) and the biodegraded fatigue (BDF) behavior of 3D-printed PLA. For this purpose, two sets of standard fatigue specimens were additively manufactured by the fused filament fabrication (FFF) method. One set was used for plain fatigue testing, and the other was immersed for 330 days in simulated body fluid (SBF). After immersion, the samples were dried and weighed before fatigue testing. The fully reversed rotary bending fatigue tests were conducted on both sets of specimens, and the stress-lifetime (S-N) curves were obtained. Additionally, the fatigue properties of PF and BDF specimens were evaluated. Moreover, the fracture behaviors of the materials were studied using field emission scanning electron microscopy (FESEM). The outcomes implied that the weight of the samples extended during the immersion period, primarily due to water absorption by the PLA. However, after drying, the final weights did not change compared to the weights before immersion. The SBF immersion significantly reduced the fatigue performance of the biodegraded samples comparing the PF result.

Implantation techniques for a helix-fixation dual-chamber leadless pacemaker

In a pivotal trial (NCT05252702), the AVEIR DR (Abbott) leadless pacemaker system was found to be safe and effective in delivering DDDR synchronous atrial and ventricular pacing. This dual-chamber system employs 2 leadless pacemakers with implant-to-implant communication. Although implantation of the ventricular device as a single-chamber pacemaker has been well described, there are additional considerations surrounding the dual-chamber implantation procedure. Herein, we review the dual-chamber leadless pacemaker implantation workflow while providing guidance to optimize safe and effective implantation procedures.

Fasting vs no fasting prior to catheterisation laboratory procedures: the SCOFF trial.

Current guidelines recommend 6 hours of solid food and 2 hours of clear liquid fasting for patients undergoing cardiac procedures with conscious sedation. There are no data to support this practice, and previous single centre studies support the safety of removing fasting requirements. The objective of this study was to determine the non-inferiority of a no fasting strategy to fasting prior to cardiac catheterisation procedures which require conscious sedation. This is a multicentre, investigator-initiated, non-inferiority randomised trial conduced in Australia with a prospective open label blinded endpoint design. Patients referred for coronary angiography, percutaneous coronary intervention or cardiac implantable electronic device (CIED) related procedures were enrolled. Patients were randomised 1:1 to fasting as normal (6 hours solid food and 2 hours clear liquid) or no fasting requirements (encouraged to have regular meals but not mandated to do so). Recruitment occurred from 2022 to 2023. The primary outcome was a composite of aspiration pneumonia, hypotension, hyperglycaemia and hypoglycaemia assessed with a Bayesian approach. Secondary outcomes included patient satisfaction score, new ventilation requirement (non-invasive and invasive), new intensive care unit admission, 30-day readmission, 30-day mortality, 30-day pneumonia. 716 patients were randomised with 358 in each group. Those in the fasting arm had significantly longer solid food fasting (13.2 versus 3.0 hours, Bayes factor >100 indicating extreme evidence of difference) and clear liquid fasting times (7.0 versus 2.4 hours, Bayes factor >100). The primary composite outcome occurred in 19.1% of patients in the fasting arm and 12.0% of patients in the no fasting arm. The estimate of the mean posterior difference in proportions in the primary composite outcome was -5.2% (95% CI -9.6 to -0.9, ) favouring no fasting. This result confirms non-inferiority (posterior probability >99.5%) and superiority (posterior probability 99.1%) of no fasting for the primary composite outcome. The no fasting arm had improved patient satisfaction scores with a posterior mean difference of 4.02 points (95% CI 3.36 to 4.67, Bayes factor >100). Secondary outcome events were similar. In patients undergoing cardiac catheterisation and CIED related procedures, no fasting was non-inferior and superior to fasting for the primary composite outcome of aspiration pneumonia, hypotension, hyperglycaemia and hypoglycaemia. Patient satisfaction scores were significantly better with no fasting. This supports removing fasting requirements for patients undergoing cardiac catheterisation laboratory procedures that require conscious sedation.

Pectoral Nerve Block II for Cardiac Implantable Electronic Devices.

This study aimed to assess the feasibility and effectiveness of the pectoral nerves (PECS) II block in facilitating cardiac implantable electronic device (CIED) insertion in a sample of 120 patients, with a focus on the percentage of cases completed without additional intraoperative local anesthesia. PECS II blocks were performed on the left side using ultrasound guidance in all 120 patients. Feasibility was assessed by the proportion of cases completed without the need for extra intraoperative local anesthetic. Secondary outcomes included the amount of additional local anesthetic used, intraoperative opioid requirements, postoperative pain scores, time to first postoperative analgesia, analgesic consumption, patient satisfaction, and block-related complications. Of the 120 patients, 78 (65%) required additional intraoperative local anesthetic, with a median volume of 8.2 mL (range 3-13 mL). Fifteen patients (12.5%) needed intraoperative opioid supplementation. Nine patients (7.5%) required postoperative tramadol for pain relief. In total, 98 patients (81.7%) reported high satisfaction levels with the procedure. The PECS II block, when combined with supplementary local anesthetic, provided effective postoperative analgesia for at least 24 h in 120 patients undergoing CIED insertion. While it did not completely replace surgical anesthesia in most cases, the PECS II block significantly contributed to a smoother intraoperative experience for patients.

Epidural magnetic stimulation of the motor cortex using an implantable coil

BackgroundMagnetic stimulation, represented by transcranial magnetic stimulation (TMS), is used to treat neurological diseases. Various strategies have been explored to improve the spatial resolution of magnetic stimulation. While reducing the coil size is the most impactful approach for increasing the spatial resolution, it decreases the stimulation intensity and increases heat generation. ObjectiveWe aim to demonstrate the feasibility of magnetic stimulation using an epidurally implanted millimeter-sized coil and that it does not damage the cortical tissue via heating even when a repetitive stimulation protocol is used. MethodsA coil with dimensions of 3.5 × 3.5 × 2.6 mm3 was epidurally implanted on the left motor cortex of rat, corresponding to the right hindlimb. Before and after epidural magnetic stimulation using a quadripulse stimulation (QPS) protocol, changes in the amplitude of motor evoked potentials (MEPs) elicited by a TMS coil were compared. ResultsThe experimental group showed an average increase of 88 % in MEP amplitude in the right hindlimb after QPS, whereas the MEP amplitude in the left hindlimb increased by 18 % on average. The control group showed no significant change in MEP amplitude after QPS in either hindlimb. The temperature changes at the coil surface remained <2 °C during repetitive stimulation, meeting the thermal safety limit for implantable medical devices. ConclusionThese results demonstrate the feasibility of epidural magnetic stimulation using an implantable coil to induce neuromodulation effects. This novel method is expected to be a promising alternative for focal magnetic stimulation with an improved spatial resolution and lowered stimulus current than previous magnetic stimulation methods.

Efficacy of Hypothermic Compression Bandages in Cardiac Device Surgical Wounds: A Randomized Controlled Trial.

Pocket hematoma is the most prevalent complication with cardiac implantable electronic devices (CIEDs), especially in patients who are undergoing oral anticoagulation and/or antiplatelet therapy. To evaluate the efficacy of hypothermic compression bandaging versus conventional compression bandaging for the prevention of surgical wound hematoma of CIEDs in patients who are undergoing chronic anticoagulant drug use and/or antiplatelet therapy. This was a single-center randomized prospective study. The intervention group received a hypothermic compression bandage, and the control group received a conventional compression bandage. The primary endpoint was the appearance of hematoma 10 days after the intervention. A total of 310 patients participated in the study. The mean age of the participants was 73.77 ± 10.68 years, and 74.8% were men. In the intervention group, 5.88% (n = 18) of patients developed ecchymosis, and 1.3% (n = 4) developed mild hematoma. In the control group, 5.88% (n = 18) of patients developed ecchymosis, and 2.9% (n = 9) developed mild hematoma. No patient in either group had a severe hematoma. No significant differences were observed between the two types of dressing in any of the three degrees of hematoma. This study demonstrated that compression bandaging with or without hypothermic therapy effectively prevents pocket hematoma of CIEDs in patients at high risk of bleeding.

2024 HRS perspective on advancing workflows for CIED remote monitoring

Cardiac implantable electronic devices (CIEDs) generate substantial data, often stored in image or PDF formats. Remote monitoring, now an integral component of patient care, places considerable administrative burdens on clinicians and staff, in large part due to the challenge of integrating these data seamlessly into electronic health records (EHRs). Since 2006, the Heart Rhythm Society, in collaboration with the CIED industry, has led an initiative to establish a unified standard nomenclature. This effort has harmonized terminology, aligning diverse terms with single terms approved by the Institute of Electrical and Electronics Engineers. With this foundational work complete, attention now turns to developing technical standards for interoperability, which would enable the smooth communication of CIED data between information technology systems used in clinical practice. In this manuscript, by leveraging Health Level 7 Fast Healthcare Interoperability Resources, we present a roadmap for the technical committee to guide this endeavor. We identify critical data exchange points between remote transceivers, EHRs, and third-party platforms commonly used for CIED patient data management. Our objective is to establish bidirectional communication among these resources, ensuring the accuracy, timeliness, and accessibility of clinical data for clinicians. We also anticipate substantial benefits for both clinical research and administrative efficiency through the implementation of this interoperability framework.

Advancing healthcare through piezoresistive pressure sensors: a comprehensive review of biomedical applications and performance metrics

Abstract Piezoresistive pressure sensors have transformed biomedical applications, enabling precise diagnostics and monitoring. This concise review explores the fundamental principles, key components, and fabrication techniques of piezoresistive pressure sensors, focusing on critical performance metrics such as sensitivity, accuracy, and response time. Biomedical design challenges, including biocompatibility and long-term stability, are examined, offering insights into solutions for optimal sensor integration. In diverse biomedical applications, piezoresistive pressure sensors play pivotal roles, from blood pressure monitoring to implantable medical devices. The paper emphasizes their versatility in enhancing patient care through continuous and accurate monitoring. Looking forward, the review discusses emerging trends and potential research directions, positioning piezoresistive pressure sensors as central contributors to the future of biomedical technology, promising improved patient outcomes and advanced healthcare delivery through precise and continuous monitoring.

A Soft-Fiber Bioelectronic Device with Axon-Like Architecture Enables Reliable Neural Recording In Vivo under Vigorous Activities.

Implantable neural devices that record neurons in various states, including static states, light activities such as walking, and vigorous activities such as running, offer opportunities for understanding brain functions and dysfunctions. However, recording neurons under vigorous activities remains a long-standing challenge because it leads to intense brain deformation. Thus, three key requirements are needed simultaneously for neural devices, that is, low modulus, low specific interfacial impedance, and high electrical conductivity, to realize stable device/brain interfaces and high-quality transmission of neural signals. However, they always contradict each other in current material strategies. Here, a soft fiber neural device capable of stably tracking individual neurons in the deep brain of medium-sized animals under vigorous activity is reported. Inspired by the axon architecture, this fiber neural device is constructed with a conductive gel fiber possessing a network-in-liquid structure using conjugated polymers and liquid matrices and then insulated with soft fluorine rubber. This strategy reconciles the contradictions and simultaneously confers the fiber neural device with low modulus (300kPa), low specific impedance (579kΩµm2), and high electrical conductivity (32700Sm-1) - ≈1-3 times higher than hydrogels. Stable single-unit spike tracking in running cats, which promises new opportunities for neuroscience is demonstrated.

Procedural and long-term outcomes of tunneled transvenous leads

BackgroundLead-related venous stenosis and occlusion can complicate the insertion or replacement of transvenous leads in patients with cardiac implantable electronic devices (CIEDs). A possible solution is to tunnel the lead from the contralateral vasculature to the ipsilateral generator. Procedural complications and long-term outcomes remain unclear with this technique. ObjectiveWe sought to assess outcomes of tunneled transvenous leads. MethodsWe retrospectively identified all patients who underwent transvenous CIED lead tunneling to a contralateral pocket at our institution between 2014 and 2024. Clinical characteristics, indications for lead implantation, postoperative complications, and long-term outcomes were collected. ResultsWe identified that 27 patients underwent transvenous lead tunneling at our institution. Most patients were men (20, 74%) with a mean age of 68.8 ± 18.3 years. Most patients had nonischemic cardiomyopathy (16, 59%) with a mean ejection fraction of 29.3% ± 11.3%. The tunneled leads were coronary sinus leads (20, 74%), followed by defibrillator leads (5, 18.5%) and right ventricular pacing leads (2, 7.4%). Implantation procedures were primarily for device upgrade (18), lead revisions (8), or de novo lead placement (1). No postoperative complications were seen. Patients were followed for a mean of 2.2 ± 1.4 years. One tunneled defibrillator lead (3.7%) had low shock impedance 3 years after implantation, which was monitored and did not require an intervention. ConclusionIn patients with ipsilateral venous occlusion, contralateral lead tunneling appears to be an effective and safe approach to manage patients with CIEDs and occluded ipsilateral subclavian veins.

326.6: Evaluation of morbidity and mortality in patients over 65 years of age with left ventricular assist device implantation.

326.6: Evaluation of morbidity and mortality in patients over 65 years of age with left ventricular assist device implantation.

Diabetes mellitus in stable chronic heart failure and the combination with humoral activation, their association, and prediction of 2-year adverse outcomes. Data from the FAR NHL registry.

The study aims to describe the role of diabetes in patients with heart failure. In all, 1052 chronic heart failure patients were included in the FARmacology and NeuroHumoral Activation (FAR NHL) multicenter prospective registry. They had ejection fraction below 50% and were on stable medication for at least 1 month. More than one-third (38.9%) of the patients had diabetes mellitus (DM). Diabetic patients (N = 409) were older (median 67 vs. 64, p < 0.001), had higher body mass index (BMI) (30 vs. 28 kg/m2, p < 0.001), much more frequently had ischemic heart disease (71 vs. 47%, p < 0.001), hypertension (80 vs. 67%, p < 0.001), dyslipidemia (89 vs. 69%, p < 0.001), worse renal function (estimated glomerular filtration rate [eGFR] median 63 vs. 73 mL/min/1.73 m2, p < 0.001), and higher N-terminal pro-brain natriuretic peptide (NT-proBNP) (median 681 vs. 463 pg/mL, p = 0.003). All-cause death, left ventricle assist device implantation, and orthotopic heart transplantation were set as the combined primary end point, which was present in 15.5% (163 patients) within the 2-year follow-up. In the 2-year follow-up, 81.0% of patients with diabetes survived without a primary end point, while 85.4% of the patients without diabetes survived, the difference being on the verge of statistical significance (p = 0.089). DM is a statistically significant predictor of NT-proBNP value in univariate analysis, but it is not an independent predictor in a multivariate analysis. When the NT-proBNP level was high, the presence of DM did not influence the prognosis. The combination of diabetes and NT-proBNP levels may better stratify the prognosis of patients with chronic heart failure.

Genophenotypic correlates and long-term outcome prognosticators of left ventricular non-compaction in children

BackgroundTo investigate the outcomes, clinical prognosticators, and genetic profiles of pediatric left ventricular non-compaction (LVNC). MethodsAll subjects were <18 years old, diagnosed with LVNC between January 2008 and December 2020. Whole-exome sequencing was undertaken. The primary endpoint was composite outcome, including death, heart transplant, and left ventricular assist device implantation. ResultsThirty-three patients were enrolled, males predominating (57.6%). Median age at diagnosis was 0.33 (0.1–7.2) years. Family history was documented in four (12.1%). Five (15.2%) had sustained arrhythmias. Mean follow-up period was 9.5 years, and 5- and 10-year event-free survival were 84.8% and 66.9%, respectively. Seven died of heart failure, four received heart transplants, and one required left ventricular assist device placement. Log of baseline NT-proBNP (adjusted odds ratio [aOR] = 4.4, p = 0.012) and lack of improvement in NT-proBNP (aOR = 41.2, p = 0.033) impacted the primary outcome most significantly. Eighteen out of 25 genetic testing (72%) revealed chromosomal anomalies, or pathogenic or likely pathogenic variants. Three genetic variants (PLEKHM2 p.G419R, RYR2 p.V2571A, and SCN5A p.M1676I) were significantly associated with the primary outcome (p = 1.52 × 10−6). ConclusionsPediatric LVNC is a rare disorder with variable genetic underpinnings. Baseline NT-proBNP values and lack of improvement in NT-proBNP levels were important predictors of poor long-term outcomes. Pathogenic genetic variants or chromosomal anomalies are not unusual.

Proteomic biomarkers related to obesity in heart failure with reduced ejection fraction and their associations with outcome.

Heart failure (HF) pathophysiology in patients with obesity may be distinct. To study these features, we identified obesity-related biomarkers from 4210 circulating proteins in patients with HF with reduced ejection fraction (HFrEF) and examined associations of these proteins with HF prognosis and biological mechanisms. In 373 patients with trimonthly blood sampling during a median follow-up of 2.1 (25th-75th percentile: 1.1-2.6) years, we applied an aptamer-based multiplex approach measuring 4210 proteins in baseline samples and the last two samples before study end. Associations between obesity (BMI > 30 kg/m2) and baseline protein levels were analyzed. Subsequently, associations of serially measured obesity-related proteins with biological mechanisms and the primary endpoint (PEP; composite of cardiovascular mortality, HF hospitalization, left ventricular assist device implantation, and heart transplantation) were examined. Obesity was identified in 26% (96/373) of patients. A total of 30% (112/373) experienced a PEP (with obesity: 26% [25/96] vs. without obesity: 31% [87/277]). A total of 141/4210 proteins were linked to obesity, reflecting mechanisms of neuron projection development, cell adhesion, and muscle cell migration. A total of 50/141 proteins were associated with the PEP, of which 12 proteins related to atherosclerosis or hypertrophy provided prognostic information beyond clinical characteristics, N-terminal pro-B-type natriuretic peptide, and high-sensitivity troponin T. Patients with HFrEF and obesityshow distinct proteomic profiles compared to patients with HFrEF without obesity. Obesity-related proteins are independently associated with HF outcome. These proteins carry potential to improve management of obesity-related HF and could be leads for future research.

Late Follow-up for a Randomized Trial of Surgical Treatment of Tricuspid Valve Regurgitation in Patients Undergoing Left Ventricular Assist Device Implantation

ObjectivesWe previously reported that concurrent tricuspid valve surgery (TVS) was not associated with a lower incidence of early RHF among patients undergoing durable LVAD implantation. This is a follow-up analysis to further define the clinical impact of concurrent TVS within 12-months of follow-up. MethodsPatients with moderate or severe TR on pre-operative echocardiography (n=71) were randomized to either LVAD implantation alone (No TVS, n=34) or with concurrent TVS (TVS, n=37). Randomization was stratified by pre-operative right ventricular dysfunction. Patients were followed for at least 12-months after surgery. The incidence of RHF was determined using INTERMACS criteria by an adjudication committee. Functional studies and repeat echocardiography were performed at 12-months. ResultsDemographics were similar between the two arms. At 12-months, the rate of moderate or severe RHF was 50.0% (No TVS) versus 51.4% (TVS). No patients developed RHF between 6- and 12-months following the procedure. Death from RHF was 5.4% (TVS) versus 8.8% (No TVS). At 12-months, there was no significant difference in TR severity between the two arms due to improvement in TR severity in the No TVS arm. On cardiopulmonary exercise testing at 12+ months, there was no significant difference in peak oxygen consumption. ConclusionsIn patients with significant pre-implant TR, the severity of TR improved over time in the LVAD implantation alone arm. By 12-months, there is no significant difference in TR severity between the two arms. This may account for the lack of difference in late clinical or functional parameters.

Active Left Atrial Ejection Fraction as a Non-Invasive Marker in Pulmonary Hypertension Secondary to Heart Failure

BackgroundPatients with pulmonary hypertension (PH) secondary to left heart failure (HF) exhibit a complex pathophysiological profile and poor prognosis. Left atrial function is pivotal in the progression of this disease, yet its predictive significance remains exclusive. This study aimed to explore the predictive capability of LA metrics in this population and compare them with other common predictors. MethodsIn this retrospective study, consecutive patients with PH secondary to HF who underwent cardiac magnetic resonance (CMR) imaging between December 2010 and December 2021 were enrolled. The composite endpoint was defined as all-cause death, heart-lung transplantation, or left ventricular assist device implantation. Survival analyses were performed using Kaplan–Meier curves and Cox regression analyses. ResultsA total of 174 patients with PH secondary to HF, with a mean age of 53.2 ± 14.9 years, including 90 men, were included in the final analysis. During a median follow-up of 31.9 months, 58 patients (33.3%) with PH reached the endpoints. There was a fair correlation between active left atrial ejection fraction (LAEF) and pulmonary artery wedge pressure (r = -0.397, p = 0.044). Active LAEF had a strong correlation with oxygen consumption at anaerobic threshold (r = 0.769, p < 0.001) and peak oxygen consumption (r = 0.754, p < 0.001). Active LAEF demonstrated comparable prognostic performance to other variables measured by echocardiography or CMR. After adjusting for clinical variables and left ventricular ejection fraction, active LAEF was still an independent predictor for adverse events (C-statistic: 0.784). Subgroup analysis among HF patients with preserved ejection fraction demonstrated that those with active LAEF ≤ 8.6% had a 7.05-fold higher risk of experiencing the composite endpoint compared to those with active LAEF > 8.6%. ConclusionAlthough active LAEF does not demonstrate statistical improvement in outcome discrimination compared to established metrics, it may still merit consideration for assessing disease severity and prognosis in patients with PH secondary to HF. The integration of active LAEF and HF subtypes may stratify individuals at different levels of risk.

Acceptance and willingness of patients with chronic facial nerve palsy for an implantable device that assists with eye closure

Patients with facial nerve palsy often experience lagophthalmos (incomplete eye closure), which can lead to exposure keratitis. The Bionic Lid Implant for Natural Eye Closure (BLINC) is a medical device designed to mimic the morenatural blink kinetics than traditional lid loading techniques. This study aimed to evaluate potential factors that might influence the design of the BLINC device and willingness of participant to undergo the implant placement surgery. Patients attending a multidisciplinary facial nerve clinic were invited to complete a survey addressing patient acceptance of the BLINC device implantation. Seventy-two patients were mailed the survey, of which 50 returned completed surveys (69%). The most important factor identified by participants was the device function (81% ranked as very important) and the least important factor was cost (16% ranked as very important). Median acceptable device function time was 5 years (range 1-10 years). Ten participants (20%) indicated willingness to be the first to trial BLINC. Women were more likely to rate visual appearance as important (OR 3.32, CI 1.14-9.62, p=0.028), and less likely to rate user friendliness as important (OR 0.16, CI 0.04-0.52, p=0.0021). Older participants were more likely to rate the length of recovery period as important (OR 1.04, CI 1.01-1.08, p=0.006). Participants with complete eye closure were less likely to be willing to trial the implant (OR 0.08, CI 0.00-0.53, p = 0.006, whilst patients with eye irritation were more willing to trial the implant (OR 7.20, CI 1.12-142, p = 0.036). Certain patient demographics impact patient aesthetic and functional preferences and the willingness to trial the BLINC device.

Cost savings associated with extended battery longevity in cardiac resynchronization therapy defibrillators (CRT-D)

BackgroundCardiac resynchronization therapy-defibrillators (CRT-D) are devices established as treatment for symptomatic heart failure patients at risk of sudden cardiac death. Battery depletion poses a significant clinical and economic burden; extended service life may reduce costs due to generator changes and associated complications. ObjectiveThis study estimated cost-savings associated with extended battery longevity in Medicare patients receiving CRT-D implantation. MethodsA decision tree was used to explore three battery capacities: 1.0 ampere-hours (Ah), 1.6Ah, and 2.1Ah. Yearly risk of all-cause mortality, device-related complications, and end of battery life were estimated. Over 6 years, estimated costs included device implantation, replacement, follow-up appointments, and complications. ResultsThe average total costs to Medicare over 6 years were $41,527, $48,515, and $56,647 per person (USD 2023) for the 2.1Ah, 1.6Ah, and 1.0Ah, respectively. The total per-person replacement cost for the 1.0Ah devices was more than 4 times that of the 2.1Ah devices ($20,126 versus $5,006). When extrapolated to the total number of CRT-D implants over a 6-year period, the difference in costs between 2.1Ah1.0Ah battery capacity exceeded $500 million. ConclusionExtended longevity CRT-D batteries demonstrate significant cost savings to Medicare over 6 years. These data indicate long-term economic considerations should be included in device selection.

Integration of Patient Reported Quality-of-life Data into Risk Assessment in Heart Failure

Optimal management of outpatients with heart failure (HF) requires serially updating the estimates of their risk for adverse clinical outcomes to guide treatment. Patient-reported outcomes (PROs) are becoming increasingly used in clinical care. The purpose of this study was to determine whether the inclusion of PROs can improve the risk prediction for HF hospitalization and death in ambulatory patients with HF. We included consecutive patients with HF with reduced ejection fraction (HFrEF) and HF with preserved EF (HFpEF) seen in a HF clinic between 2015 and 2019 who completed PROs as part of routine care. Cox regression with a least absolute shrinkage and selection operator regularization and gradient boosting machine analyses were used to estimate risk for a combined outcome of HF hospitalization, heart transplant, left ventricular assist device implantation, or death. The performance of the prediction models was evaluated with the time-dependent concordance index (Cτ). Among 1165 patients with HFrEF (mean age 59.1 ± 16.1, 68% male), the median follow-up was 487 days. Among 456 patients with HFpEF (mean age 64.2 ± 16.0 years, 55% male) the median follow-up was 494 days. Gradient boosting regression that included PROs had the best prediction performance - Cτ 0.73 for patients with HFrEF and 0.74 in patients with HFpEF, and showed very good stratification of risk by time to event analysis by quintile of risk. The Kansas City Cardiomyopathy Questionnaire overall summary score, visual analogue scale and Patient Reported Outcomes Measurement Information System dimensions of satisfaction with social roles and physical function had high variable importance measure in the models. PROs improve risk prediction in both HFrEF and HFpEF, independent of traditional clinical factors. Routine assessment of PROs and leveraging the comprehensive data in the electronic health record in routine clinical care could help more accurately assess risk and support the intensification of treatment in patients with HF.

Needle-Like Multifunctional Biphasic Microfiber for Minimally Invasive Implantable Bioelectronics.

Implantable bioelectronics has attracted significant attention in electroceuticals and clinical medicine for precise diagnosis and efficient treatment of target diseases. However, conventional rigid implantable devices face challenges such as poor tissue-device interface and unavoidable tissue damage during surgical implantation. Despite continuous efforts to utilize various soft materials to address such issues, their practical applications remain limited. Here, a needle-like stretchable microfiber composed of a phase-convertible liquid metal (LM) core and a multifunctional nanocomposite shell for minimally invasive soft bioelectronics is reported. The sharp tapered microfiber can be stiffened by freezing akin to a conventional needle to penetrate soft tissue with minimal incision. Once implanted in vivo where the LM melts, unlike conventional stiff needles, it regains soft mechanical properties, which facilitate a seamless tissue-device interface. The nanocomposite incorporating with functional nanomaterials exhibits both low impedance and the ability to detect physiological pH, providing biosensing and stimulation capabilities. The fluidic LM embedded in the nanocomposite shell enables high stretchability and strain-insensitive electrical properties. This multifunctional biphasic microfiber conforms to the surfaces of the stomach, muscle, and heart, offering a promising approach for electrophysiological recording, pH sensing, electrical stimulation, and radiofrequency ablation in vivo.