The combination of elevated BNP and AF as a predictor of no early recanalization after IV-t-PA in acute ischemic stroke

Abstract 

Background and purpose

In acute stroke patients treated with intravenous tissue plasminogen activator (t-PA), early recanalization can improve patient outcome. Heart failure may result in reduction of brain perfusion, which limits the ability of the blood stream to wash out emboli. Brain natriuretic peptide (BNP) is used as a biological marker of heart failure. Most stroke patients with atrial fibrillation (AF) have elevated BNP levels. We investigated the relationships of plasma BNP levels before t-PA infusion and AF with early recanalization after t-PA infusion.

Methods

Patients with a major brain artery occlusion were studied prospectively. MRAs were performed before and within 60min after t-PA infusion. The relationship between BNP levels before t-PA infusion and the presence of AF with early recanalization was examined.

Results

Seventy-nine patients (49 men; mean age, 75.5±10.4years; ICA occlusion in 25 patients, M1 in 32, M2 in 13, PCA in 3, and BA in 6) were enrolled. Follow-up MRA within 60min after t-PA infusion revealed recanalization in 35 (44.3%) patients and no recanalization in 44 (55.7%). Patients with AF (57.1% vs. 75.0%, P=0.0294) and BNP>150pg/dl (39.0% vs. 73.7%, P=0.0019) less frequently had early recanalization than those without AF and with BNP≤150pg/dl. The combination of AF and BNP>150pg/ml was a useful predictor for no early recanalization (positive predictive value, 79.4%; negative predictive value, 62.2%; sensitivity, 61.4%; specificity, 80.0%).

Conclusion

The presence of AF and elevated BNP was associated with no early recanalization after IV-t-PA therapy. We should need further study to ascertain its predictive ability.

Keywords: Recanalization, Tissue plasminogen activator (t-PA), BNP, AF, MRA