Cutoff Value of Admission N-Terminal Pro-Brain Natriuretic Peptide Which Predicts Poor Myocardial Perfusion after Primary Percutaneous Coronary Intervention for ST-Segment-Elevation Myocardial Infarction.

BACKGROUND: We explored the value of admission levels of N-terminal pro-brain natriuretic peptide (NTProBNP) that best predicts poor myocardial tissue perfusion following primary percutaneous coronary intervention (PPCI) in patients admitted with acute ST-segment-elevation myocardial infarction (STEMI). METHODS: We enrolled 90 consecutive patients admitted with acute STEMI who underwent PPCI and achieved post-procedural TIMI flow grade 3 in the infarct-related artery. We measured levels of NTProBNP from admission blood samples. Thereafter, we assessed post-procedural myocardial blush grade (MBG) at the end of PPCI, and further measured ST segment resolution (STR) 90 minutes following PPCI. The primary endpoint was STR < 50%; furthermore, the co-primary angiographic endpoint was postprocedural MBG 0/1. RESULTS: The mean age of study subjects was 53.6 ± 10.9 years (74.4% males). We found that NTProBNP was higher in patients with STR < 50% versus those with STR ≥ 50% (p < 0.001), and in patients with post-procedural MBG 0/1 versus those with MBG 2/3 (p < 0.001). A value of NTProBNP ≥ 420 ng/L was the optimal cutoff value that best predicted < 50% STR; it predicted < 50% STR with sensitivity, specificity, positive and negative predictive value of 98.4%, 92.3%, 96.9%, and 96%, respectively. Likewise, a value of NTProBNP ≥ 570 ng/L was the optimal cutoff value that best predicted postprocedural MBG 0/1; it predicted MBG 0/1 with sensitivity, specificity, positive and negative predictive value of 92.2%, 66.7%, 78.3%, and 86.7%, respectively. CONCLUSIONS: In patients with STEMI who underwent PPCI and ended up with successful recanalization of the epicardial infarct-related artery, elevated admission levels of NTProBNP predicted incomplete post-procedural STR with good sensitivity and specificity, and predicted poor post-procedural myocardial blush with good sensitivity and moderate specificity.