JACC Heart Failure：房颤与血浆利钠肽水平升高相关

　　在无心衰的情况下，房颤与血浆利钠肽（MR-proANP、BNP和NT-proBNP）水平升高具有相关性。论文于6月3日发表于《美国心脏病学会杂志：心衰》（JACC：Heart Failure）。

　　此项研究共纳入1445例急性呼吸困难患者。在无房颤且无心衰患者中三种利钠肽血浆浓度最低。在无心衰的房颤患者中三种利钠肽的血浆浓度显著升高，在伴和未伴房颤的心衰患者中则进一步升高（P 均<0.001）。无房颤时三种利钠肽均可有效鉴别心衰，伴房颤时MR-proANP、BNP和NT-proBNP的诊断效能则明确降低。上述结果提示房颤存在时需考虑利钠肽的不同诊断阈值。

　　专家评论指出，此项研究结果在急性心衰患者生物标志物数据临床解读，以及利用利钠肽指标作为纳入标准的临床试验设计方面均具有重要意义。新型心衰生物标志物应主要反映心衰病理生理学所涉及的重要通路，而不应是利钠肽等已有临床信息的重复。

Atrial Fibrillation Impairs the Diagnostic Performance of Cardiac Natriuretic Peptides in Dyspneic Patients:
Results From the BACH Study (Biomarkers in ACute Heart Failure)
Objectives 
The purpose of this study was to assess the impact of atrial fibrillation (AF) on the performance of mid-region amino terminal pro-atrial natriuretic peptide (MR-proANP) in comparison with the B-type peptides (BNP and NT-proBNP) for diagnosis of acute heart failure (HF) in dyspneic patients.
Background 
The effects of AF on the diagnostic and prognostic performance of MR-proANP in comparison with the B type natriuretic peptides have not been previously reported.
Methods 
A total of 1,445 patients attending the emergency department with acute dyspnea had measurements taken of MR-proANP, BNP, and NT-proBNP values on enrollment to the BACH trial and were grouped according to presence or absence of AF and HF.
Results 
AF was present in 242 patients. Plasma concentrations of all three peptides were lowest in those with neither AF nor HF and AF without HF was associated with markedly increased levels (p < 0.00001). HF with or without AF was associated with a significant further increment (p < 0.00001 for all three markers). Areas under receiver operator characteristic curves (AUCs) for discrimination of acute HF were similar and powerful for all peptides without AF (0.893 to 0.912; all p < 0.001) with substantial and similar reductions (0.701 to 0.757) in the presence of AF. All 3 peptides were independently prognostic but there was no interaction between any peptide and AF for prediction of all-cause mortality.
Conclusions 
AF is associated with increased plasma natriuretic peptide (MR-proANP, BNP and NT-proBNP) levels in the absence of HF. The diagnostic performance of all three peptides is impaired by AF. This warrants consideration of adjusted peptide thresholds for diagnostic use in AF and mandates the continued search for markers free of confounding by AF.