Cygankiewicz Iwona, Zareba Wojciech, Vazquez Rafael, Almendral Jesus, Bayes-Genis Antoni, Fiol Miquel, Valdes Mariano, Macaya Carlos, Gonzalez-Juanatey Jose R, Cinca Juan, Bayes de Luna Antoni
Institut Català Ciències Cardiovasculars, Barcelona, Spain; and Heart Research Follow-up Program, University of Rochester, Rochester New York, USA.
J Cardiovasc Electrophysiol. 2008 Oct;19(10):1066-72. doi: 10.1111/j.1540-8167.2008.01210.x. Epub 2008 Jun 28.
Repolarization dynamics, reflecting adaptation of QT to changing heart rate, is considered a marker of unfavorable prognosis in patients with heart diseases. We aimed to evaluate the prognostic value of QT/RR slope in predicting total mortality (TM) and sudden death (SD) in patients with congestive heart failure (CHF).
In 651 sinus rhythm patients with CHF in NYHA class II-III enrolled in the MUSIC study, 24-hour Holter monitoring was performed at enrollment to assess slope of the QTa/RR (QT apex) and QTe/RR (QTend) during the entire 24-hour Holter recording and separately during day and night periods. Patients were followed for a median of 44 months, with the primary endpoint defined as TM and the secondary as SD. Analysis of repolarization dynamics was feasible in 542 patients (407M), mean age 63 years, 83% in NYHA class II, 49% with ischemic cardiomyopathy, with mean LVEF 37%. Mean value of QTa/RR slope was 0.172 and QTe/RR was 0.193. During the 44-month follow-up there were 119 deaths including 47 SD. Nonsurvivors were characterized by steeper QT/RR slopes. Increased QT/RR slopes during the daytime (>0.20 for QTa and >0.22 for QTe) were independently associated with increased TM in multivariate analysis after adjustment for clinical covariates with respective hazard ratios 1.57 and 1.58, P = 0.002. None of the dynamic repolarization parameters was associated with increased risk of SD in the entire population.
Abnormal repolarization dynamics reflected as increased daytime QT/RR slopes is an independent risk stratifier of all-cause mortality in patients with chronic heart failure.
复极动力学反映了QT间期对心率变化的适应性，被认为是心脏病患者不良预后的一个标志。我们旨在评估QT/RR斜率在预测充血性心力衰竭（CHF）患者全因死亡率（TM）和猝死（SD）方面的预后价值。
在纳入MUSIC研究的651例纽约心脏协会（NYHA）心功能II-III级的窦性心律CHF患者中，入组时进行了24小时动态心电图监测，以评估整个24小时动态心电图记录期间以及白天和夜间时段QTa/RR（QT峰）和QTe/RR（QT末）的斜率。患者随访时间中位数为44个月，主要终点定义为TM，次要终点为SD。对542例患者（407例男性）进行复极动力学分析是可行的，平均年龄63岁，83%为NYHA心功能II级，49%患有缺血性心肌病，平均左心室射血分数（LVEF）为37%。QTa/RR斜率的平均值为0.172，QTe/RR为0.193。在44个月的随访期间，有119例死亡，包括47例SD。非幸存者的QT/RR斜率更陡。在调整临床协变量后，多因素分析显示白天QT/RR斜率增加（QTa>0.20，QTe>0.22）与TM增加独立相关，相应的风险比分别为1.57和1.58，P = 0.002。在整个人群中，没有一个动态复极参数与SD风险增加相关。
白天QT/RR斜率增加所反映的异常复极动力学是慢性心力衰竭患者全因死亡率的独立风险分层指标。
