{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T14:03:17Z","timestamp":1771423397671,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T00:00:00Z","timestamp":1771372800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Sudden unexplained cardiac death (SUCD) is unpredictable, causing major emotional, economic, and productivity loss. In young, apparently healthy individuals, it remains one of the most challenging causes of mortality to understand mechanistically, and no validated molecular biomarkers are currently available to support investigation of subclinical cardiac electrical vulnerability. Conventional clinical assessment tools such as electrocardiography, echocardiography, and genetic testing often fail to detect early molecular disturbances that precede electrical or structural cardiac abnormalities. Recent evidence suggests that oxidative stress and redox imbalance play a crucial mechanistic role in cardiac electrical instability, modulating ion channel function, calcium handling, mitochondrial signaling, and intercellular coupling. This literature review explores the emerging role of salivary redox biomarkers as a non-invasive research framework for exploring redox-related mechanisms relevant to cardiac electrophysiology, introducing the concept of a \u201cSalivary Redoxome\u201d\u2014an integrated oxidative\u2013antioxidative profile measurable in saliva that may reflect systemic redox homeostasis in an exploratory context, without implying myocardial specificity. Key antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), together with oxidative damage indices such as malondialdehyde (MDA) and total antioxidant capacity (TAC), are discussed for their theoretical mechanistic relevance, biological plausibility, and current limitations. Methodological considerations, sources of pre-analytical variability, and challenges related to biomarker specificity and validation are also addressed to contextualize the current evidence base. At present, no direct clinical evidence links salivary oxidative stress markers to sudden unexplained cardiac death or to electrophysiological arrhythmic risk, and their proposed relevance is therefore exploratory and hypothesis-generating. This review positions salivary redox profiling as a research approach rather than a clinical screening, predictive, or preventive tool, and outlines a future research agenda aimed at systematic validation in well-designed prospective studies.<\/jats:p>","DOI":"10.3390\/medicina62020394","type":"journal-article","created":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T12:59:16Z","timestamp":1771419556000},"page":"394","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Salivary Redox Biomarkers as a Non-Invasive Research Framework for Exploring Redox-Related Cardiac Electrical Vulnerability in Sudden Unexplained Cardiac Death: A Mechanistic and Narrative Review"],"prefix":"10.3390","volume":"62","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-9366-9386","authenticated-orcid":false,"given":"Ahmed Adel Mansour","family":"Kamar","sequence":"first","affiliation":[{"name":"Medical Department, Gulf of Suez Petroleum Company (GUPCO)\u2014Cairo Office, Cairo 11511, Egypt"},{"name":"Department of Orthopedics and Traumatology, Clinical Recovery Hospital (Recuperare), 700661 Iasi, Romania"},{"name":"Doctoral School, Faculty of Biology, \u201cAlexandru Ioan Cuza\u201d University of Iasi, 700505 Iasi, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9844-4010","authenticated-orcid":false,"given":"Ioannis","family":"Mavroudis","sequence":"additional","affiliation":[{"name":"Neuroscience Department, Leeds Teaching Hospitals NHS Trust, Leeds LS1 3EX, UK"},{"name":"Laboratory of Neuropathology & Electron Microscopy, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alin","family":"Ciobica","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Biology, \u201cAlexandru Ioan Cuza\u201d University of Iasi, 700505 Iasi, Romania"},{"name":"\u201cIoan H\u0103ulic\u0103\u201d Institute, \u201cApollonia\u201d University, 700511 Iasi, Romania"},{"name":"Biomedical Research Group, \u201cOlga Necrasov\u201d Center, Romanian Academy, 700481 Iasi, Romania"},{"name":"Academy of Romanian Scientists, Ilfov No. 3, 030167 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Diana","family":"Gheban","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and Biomedical Sciences, Apollonia University, 700511 Iasi, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1161\/CIRCULATIONAHA.124.069431","article-title":"Declining trend of sudden cardiac death in younger individuals: A 20-year nationwide study","volume":"151","author":"Hansen","year":"2025","journal-title":"Circulation"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Radu, I., Farcas, A.O., Nyulas, V., Radu, C.C., and Brinzaniuc, K. 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