Elevated systemic immune-inflammation index independently predicted left atrial thrombus in non-valvular atrial fibrillation (OR 1.13 per 100-unit increase; 95% CI 1.08-1.18; P<0.001).
Observational (n=847)
Does the systemic immune-inflammation index predict left atrial thrombus in patients with non-valvular atrial fibrillation?
Elevated systemic immune-inflammation index is an independent predictor of left atrial thrombus in patients with non-valvular atrial fibrillation, offering useful discriminatory performance to support individualized decisions regarding TEE referral.
Effect estimate: OR 1.13 per 100-unit increase (95% CI 1.08-1.18)
p-value: p=<0.001
Non-valvular atrial fibrillation (NVAF) serves as a primary cause of cardioembolic stroke, with left atrial thrombus (LAT) functioning as its major thrombotic substrate. The systemic immune-inflammation index (SII) has gained recognition as a dependable biomarker in cardiovascular disease. Nevertheless, its relationship with LAT in NVAF patients has not been thoroughly characterized in large-scale investigations. This retrospective study enrolled 847 NVAF patients who underwent transesophageal echocardiography (TEE). The primary outcome was TEE-detected left atrial thrombus (LAT). Patients were stratified into LAT-positive and LAT-negative groups. Univariable and multivariable logistic regression analyses identified independent predictors of LAT. Receiver operating characteristic (ROC) curve analysis evaluated the diagnostic performance of SII compared to the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and CHA₂DS₂-VASc score. Restricted cubic spline (RCS) analysis assessed the dose-response relationship between SII and LAT risk, and prespecified subgroup analyses examined whether this association remained consistent according to oral anticoagulant (OAC) use and other clinical strata. Of 847 patients, 142 (16.8%) were LAT-positive. Elevated SII was an independent predictor of LAT (OR = 1.13, 95% CI: 1.08–1.18 per 100-unit increase; P < 0.001) after adjusting for conventional risk factors. The optimal SII cutoff was 712.5 (AUC 0.786), showing slightly better discrimination than NLR, PLR, and CHA₂DS₂-VASc score. RCS analysis revealed a significant nonlinear dose-response relationship between SII and LAT risk, and the association remained consistent in both adequate-OAC and non-OAC subgroups. Elevated SII is independently associated with LAT in NVAF patients and offers useful discriminatory performance as an adjunct, rather than a standalone substitute, for established clinical assessment. As a readily accessible hematological parameter, SII may help identify patients with a low probability of LAT while supporting individualized decisions regarding TEE referral and anticoagulation management. SII is an independent predictor of LAT in NVAF; optimal cutoff 712.5 (AUC 0.786); association consistent across OAC subgroups.
Wang et al. (Sun,) conducted a observational in Non-valvular atrial fibrillation (NVAF) (n=847). Systemic immune-inflammation index (SII) was evaluated on TEE-detected left atrial thrombus (LAT) (OR 1.13 per 100-unit increase, 95% CI 1.08-1.18, p=<0.001). Elevated systemic immune-inflammation index independently predicted left atrial thrombus in non-valvular atrial fibrillation (OR 1.13 per 100-unit increase; 95% CI 1.08-1.18; P<0.001).