Wireless, Battery-Free Implantable Hemodynamic Sensors for Closed-Loop Heart Failure Management: A Systematic Review of Clinical Feasibility, Efficacy, and Challenges

Background: Heart failure (HF) remains a leading cause of hospitalization and death worldwide. Conventional telemonitoring of weight and symptoms has yielded mixed results in preventing decompensation. Wireless, battery-free implantable hemodynamic sensors offer a novel closed-loop approach to HF management by continuously tracking intracardiac pressures to enable preemptive therapy adjustments. We systematically reviewed the clinical feasibility, efficacy, and challenges (including accuracy, safety, cybersecurity, and reimbursement) of such sensors in HF. Methods: We searched PubMed, EMBASE, IEEE Xplore, Scopus, and ClinicalTrials.gov (2015–2024) for studies on “implantable hemodynamic sensor” OR “wireless pressure monitor” in HF, combined with “battery-free” OR “RF-powered” OR “bio-piezoelectric”, and “closed-loop” OR “cloud monitoring”. We included clinical and preclinical studies (2015–2024) reporting sensor accuracy, longevity, HF outcomes, cybersecurity measures, or reimbursement models. Non-implantable devices, reviews, and non-English reports were excluded from the analysis. Population-Intervention-Comparator-Outcome (PICO) criteria were: HF patients (population); wireless battery-free implantable sensors (intervention); standard telemonitoring or care (comparator); and outcomes including sensor accuracy, safety, HF hospitalisation, and cost-effectiveness. Two reviewers independently screened and extracted data, resolving discrepancies by consensus. Risk of bias was assessed using Cochrane RoB2 for RCTs, ROBINS-I for observational studies, and SYRCLE for preclinical studies. PRISMA guidelines were followed. Results: From 380 records identified, 30 studies met the inclusion criteria (Figure 1). These included 5 randomized trials (including CHAMPION, LAPTOP-HF, GUIDE-HF, MONITOR-HF) and 8 observational studies of pulmonary artery (PA) pressure sensors, 2 first-in-human trials of left atrial (LA) pressure sensors, 1 meta-analysis, 3 engineering reports of new sensors, and other supporting studies. Battery-free PA sensors (CardioMEMSTM and CordellaTM) demonstrated high accuracy (mean pressure errors ~1–2 mmHg) and durable performance beyond 1–2 years. In the CHAMPION trial, daily PA pressure-guided therapy reduced HF hospitalizations by 33% vs. standard care, with sustained benefits over 18 months and low device-related complication rates (~1%). The open-access phase confirmed the persistence of benefits without safety issues. A subsequent RCT (GUIDE-HF) in a broader HF cohort did not significantly reduce events overall, largely due to the COVID-19 impact, but showed a significant 19% reduction in HF events when pre-pandemic data were isolated. A European RCT (MONITOR- HF) demonstrated that PA monitoring improved quality of life (Kansas City Cardiomyopathy Questionnaire +7 points) and reduced HF hospitalizations, with 98% freedom from sensor failures at 1 year. Direct LA pressure sensors have shown promising accuracy (mean difference vs. catheter 0.22±4.9 mmHg) and improved HF functional class in early studies. However, an earlier LA monitor trial (LAPTOP-HF) was halted due to implantation complications, highlighting procedural challenges despite a post-hoc 43% reduction in HF hospitalization in the treatment group. No fully automated (“closed-loop”) therapy delivery has been realized yet, but implant data have enabled more timely medication titration. Patient adherence to daily readings was high in trials, and no sensor-related cybersecurity breaches were reported. Nonetheless, all wireless implants transmit sensitive data, necessitating robust encryption and FDA cybersecurity compliance. Reimbursement models are evolving: the CardioMEMS PA sensor is cost-effective (~$45,000 per quality-adjusted life year) and covered by Medicare under evidence development, and a second PA sensor (Cordella) received FDA approval in 2024 after showing low HF hospitalization rates (0.16 per patient-year) in trials. Conclusions: Wireless battery-free hemodynamic sensors have demonstrated clinical feasibility and efficacy in HF, especially PA pressure monitors that significantly reduce decompensation events. These sensors achieve high accuracy without batteries, enabling long-term monitoring. Early data for LA pressure sensors indicate potential benefits if procedural safety can be ensured. Realizing closed-loop HF management will require integrating sensor data into automated decision algorithms and addressing cybersecurity and workflow challenges. Overall, implantable pressure sensors represent a paradigm shift toward proactive HF care, with evidence of improved outcomes and emerging support for cost-effectiveness. Future research should focus on broader patient populations, fully closed-loop system development, and strategies to streamline data utilization in clinical practice.