Background/Aims: Mid-regional pro-atrial natriuretic peptide (MR-proANP), a biologically stable peptide fragment of the ANP precursor, is associated with cardioembolic stroke (CES). This study aimed to investigate the significance of blood MR-proANP levels in patients with hyperacute ischemic stroke (HAIS) as a biomarker for CES.
Methods: In a multicenter observational study conducted between 2017 and 2019, we collected blood samples from patients with HAIS admitted to our hospitals within 4.5 hours of symptom onset or last known well time. The primary analysis aimed to evaluate the predictive value of MR-proANP levels for the diagnosis of CES, based on the Trial of ORG 10172 in Acute Stroke Treatment classification. Furthermore, we focused on three subgroups: 1) patients with onset-to-door time ≤1 hour, 2) patients with large vessel occlusion, and 3) patients without prior history of atrial fibrillation or atrial fibrillation on admission.
Results: Among 122 HAIS patients (median age, 77 years; male, 59%), 54 were diagnosed with CES. Patients with CES consistently exhibited higher MR-proANP levels at onset (upon arrival at the hospital), day 3, day 7, and day 14, compared to patients with other stroke subtypes. In receiver operating characteristic analysis, high discriminative ability of MR-proANP level for predicting CES was demonstrated (area under the curve, 0.89 [95% CI, 0.84–0.95]). MR-proANP levels were significantly associated with CES in the primary analysis (adjusted odds ratio, 10.14; 95% CI, 3.78–27.2) and in the analysis of the three subgroups.
Conclusion: Higher MR-proANP levels independently predict CES in patients with HAIS.