Department of Clinical Sciences, Lund University, Malmö, Sweden
Department of Clinical Physiology, Skånes universitetssjukhus Malmö, Malmö, Sweden.
Heart. 2020 Feb;106(4):287-291. doi: 10.1136/heartjnl-2019-315119. Epub 2019 Aug 12.
Low resting heart rate and premature atrial contractions (PACs) predict incident atrial fibrillation (AF) and could be interdependent, since PACs occur in the gaps between normal beats.
To study the association between low heart rate at 24hECG, PACs and incident AF in a prospective population-based cohort.
In the Malmö Diet and Cancer study, 24hECGs were performed in 377 AF-free subjects. The endpoint was clinical AF retrieved from national hospital (mean follow-up 17 years). The interaction between increased supraventricular activity (SVA) top quartile of either PACs/hour or supraventricular tachycardias/hour) and mean heart rate (mHR) as regards AF risk was assessed in multivariable Cox regression analyses adjusted for age, sex, height, BMI, systolic blood pressure, antihypertensive medication, smoking and homeostasis model assessment of insulin resistance.
There were 80 (21%) incident cases of AF. Below median mHR (80 bpm/75 bpm for women/men) was associated with increased AF incidence (HR: 1.89, 95% CI 1.18 to 3.02, p=0.008). There was no correlation between mHR and SVA (p=0.6) or evidence of a multiplicative interaction between these factors for AF risk (p for interaction=0.6) In the group with both increased SVA and below median mHR (17% of the population) the relative risk of AF was very high (HR 4.5, 95% CI 2.2 to 9.1, p=0.001).
Low mHR at 24hECG independently predicts AF, but there is no association between mHR and SVA, and these factors are independent as regards AF risk. Subjects with both low mHR and increased SVA have high AF risk.
静息时的低心率和房性期前收缩（PACs）可预测房颤（AF）的发生，且两者可能相互影响，因为 PACs 发生在正常心跳之间的间隙中。
在一项前瞻性基于人群的队列研究中，研究 24 小时心电图（ECG）时的低心率、PACs 与房颤（AF）事件之间的关系。
在马尔默饮食与癌症研究中，对 377 例无房颤的患者进行了 24 小时心电图检查。终点是从全国医院检索到的临床房颤（平均随访 17 年）。使用多变量 Cox 回归分析，评估了增加的室上性活动（SVA）（PACs/小时或室上性心动过速/小时的上四分位数）与平均心率（mHR）之间的相互作用，以及这些因素对 AF 风险的影响，调整了年龄、性别、身高、BMI、收缩压、降压药物、吸烟和胰岛素抵抗的稳态模型评估。
共有 80 例（21%）发生房颤。低于中位数的 mHR（女性/男性为 80bpm/75bpm）与房颤发生率增加相关（HR：1.89，95%置信区间 1.18 至 3.02，p=0.008）。mHR 与 SVA 之间没有相关性（p=0.6），也没有证据表明这些因素对 AF 风险存在乘法相互作用（交互作用的 p 值=0.6）。在 SVA 增加且 mHR 低于中位数的人群（占人口的 17%）中，房颤的相对风险非常高（HR 4.5，95%置信区间 2.2 至 9.1，p=0.001）。
24 小时心电图的低 mHR 可独立预测 AF，但 mHR 与 SVA 之间没有关联，且这些因素与 AF 风险无关。mHR 低且 SVA 增加的患者具有较高的房颤风险。
