Summary
| Direction in Atrial Fibrillation | ↕ Inconsistent — reported as both higher and lower across studies, with no consistent direction |
|---|---|
| Category | Inflammatory |
| Compared against | healthy subjects |
| Associated symptoms | not linked to specific symptoms; includes both rheumatic and nonrheumatic AF patients; fibrinogen elevated only in rheumatic AF subgroup |
| Test type | Blood test (serum / plasma / whole blood) |
| LOINC code | 3255-7 |
| Source | Roldán et al. 1998 — doi:10.1016/s0002-8703(98)70149-8 |
| Condition atlas | Atrial Fibrillation Biomarker Atlas |
Other conditions where Fibrinogen is reported
- Fibrinogen in COPD — ↑ elevated vs smokers/COPD vs non-smokers
- Fibrinogen in Long COVID — ↑ elevated vs HC
See the cross-condition hub: Fibrinogen across conditions.
Related Inflammatory markers in Atrial Fibrillation
- CRP ↑
Full list: Atrial Fibrillation Biomarker Atlas.
Frequently asked questions
Is Fibrinogen high or low in Atrial Fibrillation?
Mixed. Some studies report higher and others lower Fibrinogen in Atrial Fibrillation compared with healthy subjects, so no single direction is established. Source: Roldán et al. 1998.
What symptoms is Fibrinogen associated with in Atrial Fibrillation?
The cited literature associates this marker with not linked to specific symptoms; includes both rheumatic and nonrheumatic AF patients; fibrinogen elevated only in rheumatic AF subgroup. These are population-level associations and do not mean the marker causes the symptoms.
Which test measures Fibrinogen?
It is measured as a blood test (serum / plasma / whole blood). The standard laboratory code is LOINC 3255-7. Many of the cited studies used research-grade assays, so clinical availability may vary.
Is one abnormal Fibrinogen result diagnostic of Atrial Fibrillation?
No. No single biomarker is diagnostic of Atrial Fibrillation. Fibrinogen findings come from group comparisons, overlap considerably between patients and controls, and vary with study design, timing and comparison group. A result should be interpreted by a clinician alongside symptoms, history and other tests.
Is Fibrinogen specific to Atrial Fibrillation?
No. The same marker is also reported in COPD, Long COVID in this atlas, so it reflects shared biology (for example inflammation or vascular stress) rather than a condition-specific signature.
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Last reviewed: 2026-10-08 · Page generated from atrial-fibrillation.json · Browse: Atrial Fibrillation atlas · Biomarker Index · All marker pages
Disclaimer: This page is an educational synthesis of published, peer-reviewed research and is not medical advice. Biomarker findings vary across studies with case definitions, comparison groups, timing and assay methods. Direction of change reflects the predominant finding in the cited source and does not establish a diagnostic threshold. Discuss any test result with a qualified clinician.