N-端脑钠素前体预测孤立性心房颤动复律后复发的临床研究

Clinical investigation of Nt-proBNP predicting recurrence after cardioversion of lone atrial fibrillation

目的研究孤立性心房颤动（Af）患者转复窦性心律前后，血浆N-端脑钠素前体（Nt—proBNP）水平变化与预测复律后Af复发的临床价值。方法选取62例孤立性Af并药物或电复律成功的患者，随访4周，24h动态心电图（Holter-ECG）观察随访期心律，采用放射免疫法测定复律前基线水平及复律后2h和随访4周后血浆Nt—proBNP浓度。结果Nt-proBNP基线水平较正常值明显增高（868 μg/L与334μg／L，P〈0．05）．复律后2h血浆Nt—proBNP浓度稍有下降。随访期39例患者维持窦性心律（SR组），23例患者Af复发（Af组），SR组4周后血浆Nt-proBNP浓度较基线水平明显下降[762μg/L，（623-1 140）μg/L与321μg／L，（198～525）μg/L，P〈0．05]，Af组4周后血浆Nt—proBNP浓度较基线水平无明显变化[1250μg/L，（952～1547）μg/L与1122μg/L，（923-1540）μg/L，P〉0．05]，R组Nt—proBNP基线水平显著低于Af组（P〈0．05）。Nt—proBNP基线水平对预测复律后Af复发的ROC曲线，曲线下面积0．81，900μg/L是预测复律后Af复发的最佳截断点。结论Nt—proBNP基线水平预测孤立性Af复律后复发可能有一定的临床价值，高水平的Nt—proBNP患者复律后Af容易复发，窦性心律较难维持。

Objective To investigate the clinical significance of N-terminal proB-type natriuretic peptide （Nt- proBNP） predicting the recurrence of atrial fibrillation （Af） after cardioversion in patients with lone Af. Methods Sixty- two patients with lone Af were provided with an Hoher-ECG monitoring rhythm for a follow-up period of 4 weeks after primarily successful cardioversion. Nt-proBNP serum levels were measured by RIA technique before, 2 hours and 4 weeks after cardioversion. Results The plasma concentration of baseline Nt-proBNP in all patients before cardioversion was higher than reference value（868 μg/L vs 334 μg/L,P〈0.05） and slightly decreased 2 hours after cardioversion （P〉0.05）. Thirty-nine patients were in sinus rhythm （SR group） during follow-up, in r-ecurrence of Af （Af group）. SR group showed a significant Nt-proBNP-decrease during follow-up [726 μg/L, （623-1140） μg/L vs 321 μg/L, （198-525） μg/L, P〈 0.05], but Af group remained unchanged [1 250 μg/L, （952-1 547） μg/L vs 1 122 μg/L, （923-1 540） μg/L, P〉0.05]. Baseline Nt-proBNP in SR group significantly higher in comparison to Af group （P〈0.05）. The area under the curve of the receiver- operating characteristic curve was 0.81 for Nt-proBNP to predict the recurrence of Af after eardioversion. The optimized cut-off level of 900μg/L could be used to predict the recurrence of Af with high accuracy on. Conclusion The recurrence of Af after cardioversion might be predicted by the baseline Nt-proBNP level. The patients with higher level of Nt-proBNP were more predispose to the recurrence of Af and the sinus rhythm stability could not be controlled easily.