{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T02:18:39Z","timestamp":1790389119304,"version":"4.1.0"},"reference-count":36,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,18]],"date-time":"2025-09-18T00:00:00Z","timestamp":1758153600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>This study describes the design and validation of an experimental setup for testing photoplethysmographic (PPG) devices intended for the non-invasive monitoring of vascular accesses in hemodialysis patients. Continuous assessment of arteriovenous fistulas is essential to detect pathological conditions such as stenosis, which can compromise patient safety and dialysis efficacy. While PPG-based sensors are capable of detecting such anomalies, their clinical applicability must be supported by controlled in vitro validation. The developed system replicates the anatomical, mechanical, optical, and hemodynamic features of vascular accesses. A 3D fistula model was designed and fabricated via 3D printing and silicone casting. The hydraulic circuit used red India ink and a PWM-controlled pump to simulate physiological blood flow, including stenotic conditions. Quantitative validation confirmed anatomical accuracy within 0.1 mm tolerance. The phantom exhibited an average Shore A hardness of 20.3 \u00b1 1.1, a Young\u2019s modulus of 10.4 \u00b1 0.9 MPa, and a compression modulus of 105 MPa\u2014values consistent with soft tissue behavior. Burst pressure exceeded 2000 mmHg, meeting ISO 7198:2016 standards. Flow rates (400\u2013700 mL\/min) showed &lt;1% error. Compliance was 2.4 \u00b1 0.2, and simulated blood viscosity was 3.9 \u00b1 0.3 mPa\u00b7s. Systolic and diastolic pressures fell within physiological ranges. Photoplethysmographic signals acquired using a MAX30102 sensor (Analog devices Inc., Wilmington, MA, USA) reproduced key components of in vivo waveforms, confirming the system\u2019s suitability for device testing.<\/jats:p>","DOI":"10.3390\/bioengineering12090990","type":"journal-article","created":{"date-parts":[[2025,9,18]],"date-time":"2025-09-18T12:54:26Z","timestamp":1758200066000},"page":"990","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Experimental Setup for the Validation of Photoplethysmography Devices for the Evaluation of Arteriovenous Fistulas"],"prefix":"10.3390","volume":"12","author":[{"given":"Simone","family":"Chiorboli","sequence":"first","affiliation":[{"name":"Unit of Chemical-Physics Fundamentals in Chemical Engineering, Department of Engineering, University Campus Bio-Medico of Rome, Via \u00c1lvaro del Portillo, 21, 00128 Roma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adriano","family":"Brugnoli","sequence":"additional","affiliation":[{"name":"Unit of Chemical-Physics Fundamentals in Chemical Engineering, Department of Engineering, University Campus Bio-Medico of Rome, Via \u00c1lvaro del Portillo, 21, 00128 Roma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2421-3938","authenticated-orcid":false,"given":"Vincenzo","family":"Piemonte","sequence":"additional","affiliation":[{"name":"Unit of Chemical-Physics Fundamentals in Chemical Engineering, Department of Engineering, University Campus Bio-Medico of Rome, Via \u00c1lvaro del Portillo, 21, 00128 Roma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"726","DOI":"10.2214\/AJR.15.14650","article-title":"Arteriovenous fistulas and their characteristic sites of stenosis","volume":"205","author":"Quencer","year":"2015","journal-title":"Am. 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