Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland; Finnish Cardiovascular Research Center Tampere, Tampere, Finland; Heart Hospital, Tampere University Hospital, Tampere, Finland.
Computational Physics Laboratory, Tampere University, Tampere, Finland.
JACC Clin Electrophysiol. 2024 Sep;10(9):2010-2020. doi: 10.1016/j.jacep.2024.04.018. Epub 2024 Jun 12.
Conventional measures of heart rate variability (HRV) have shown only modest associations with sudden cardiac death (SCD). Detrended fluctuation analysis (DFA), with novel methodological developments to evaluate the short-term scaling exponent, is a potentially superior method compared to conventional HRV tools.
In this study, the authors studied the analysis of the association between DFA and SCD.
The investigators studied the predictive value of ultra-short-term heart rate fluctuations (1-minute electrocardiogram samples) with DFA at rest and during different stages of physical exertion for incident SCD among 2,794 participants undergoing clinical exercise testing in the prospective FINCAVAS (Finnish Cardiovascular Study). The novel key DFA measure, the short-scale scaling exponent computed with second-order detrending (DFA2 α), was the main exposure variable. SCDs were defined by American Heart Association/European Society of Cardiology criteria using death certificates with written accounts of the events.
During a median follow-up of 8.3 years (Q1-Q3: 6.4-10.5), 83 SCDs occurred. DFA2 α measured at rest (but not in exercise) associated highly significantly with the risk of SCD, with 1-SD lower values associating with a 2.4-fold (Q1-Q3: 2.0-3.0) risk (P < 0.001). The results persisted when adjusting for other major risk factors for SCD, including age, cardiovascular morbidities, cardiorespiratory fitness, heart rate reduction, and left ventricular ejection fraction. Associations between conventional HRV parameters (measured at any stage of exercise or at rest) and SCD were substantially weaker and statistically nonsignificant after adjusting for other risk factors.
Ultra-short-term DFA2 α, when measured at rest, is a powerful and independent predictor of SCD. The association between DFA2 α and SCD is modified by physical exertion.
传统的心率变异性（HRV）测量方法与心脏性猝死（SCD）仅有中等程度的关联。趋势波动分析（DFA）是一种新兴的方法，通过评估短期标度指数，可能比传统的 HRV 工具更优越。
本研究旨在分析 DFA 与 SCD 之间的关联。
研究人员研究了 2794 名接受临床运动测试的参与者，通过 DFA 分析在休息和不同运动阶段下极短时间（1 分钟心电图样本）的心率波动与 SCD 之间的关系。新型关键 DFA 指标，使用二阶去趋势（DFA2α）计算的短标度标度指数，是主要的暴露变量。SCD 通过美国心脏协会/欧洲心脏病学会标准定义，使用死亡证明和书面事件报告。
中位随访 8.3 年（Q1-Q3：6.4-10.5）期间，发生了 83 例 SCD。DFA2α 在休息时（而非运动时）与 SCD 风险高度相关，1-SD 降低值与 2.4 倍（Q1-Q3：2.0-3.0）的风险相关（P<0.001）。当调整其他 SCD 的主要危险因素（包括年龄、心血管合并症、心肺适应能力、心率降低和左心室射血分数）后，结果仍然存在。当调整其他风险因素后，常规 HRV 参数（在运动或休息的任何阶段测量）与 SCD 之间的关联明显减弱且统计学上无显著性。
休息时的超短期 DFA2α 是 SCD 的强大且独立的预测指标。DFA2α 与 SCD 之间的关联受到体力活动的影响。
