Serum potassium levels, cardiac arrhythmias, and mortality following non-ST-elevation myocardial infarction or unstable angina: insights from MERLIN-TIMI 36.
Serum potassium levels, cardiac arrhythmias, and mortality following non-ST-elevation myocardial infarction or unstable angina: insights from MERLIN-TIMI 36.
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DOI：
10.1177/2048872615624241
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发表时间：
2017-02
期刊：
影响因子：
--
通讯作者：
Scirica BM
中科院分区：
文献类型：
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作者：
Patel RB;Tannenbaum S;Viana-Tejedor A;Guo J;Im K;Morrow DA;Scirica BM
在急性冠脉综合征（ACS）中，钾水平<3.5 mEq/L与室性心律失常有关。因此，目前的指南建议ACS患者的钾目标为4.0 mEq/L。我们的研究评估了非st段抬高型心肌梗死或不稳定型心绞痛患者钾水平、心律失常和心血管死亡之间的关系。在MERLIN-TIMI 36试验中，在随机分配接受雷诺嗪或安慰剂之前，对6515名患者的钾水平进行了测量。通过7天的连续心电图评估来确定非持续性室性心动过速（NSVT）和心室暂停的发生率。采用多变量校正的Cox比例风险回归模型评估钾水平与心血管死亡之间的关系。在钾水平<3.5 mEq/L时，持续至少8次连续心跳的nst比在钾水平大于或等于5 mEq/L时更频繁地发生（10.1 vs. 4.5%, p=0.03，趋势），而在钾水平小于或等于5 mEq/L时，观察到心室暂停>.3 s的相反模式，在钾水平大于或等于5 mEq/L时，比在钾水平小于或等于3.5 mEq/L时更频繁地发生（5.9 vs. 2.0%, p=0.03，趋势）。入院时钾水平与早期和晚期心血管死亡风险呈u型关系。与钾水平为3.5至<4 mEq/L的患者相比，钾水平<3.5 mEq/L与第14天（2.4 vs. 0.8%, HRadj 3.1, p=0.02）和一年后（6.4 vs. 3.0%, HRadj 2.2, p=0.01）心血管死亡风险增加相关。在钾水平大于或等于4.5 mEq/L时，一年内心血管死亡的风险也显著增加，并且在钾水平大于或等于5 mEq/L时也注意到类似的趋势。入院时钾水平在3.5 - 4.5 mEq/L之间的患者心血管死亡风险最低。低钾和高钾水平均与快速性心律失常和慢速性心律失常相关，提示在钾稳态极值时心血管死亡风险增加的潜在机制解释。
In acute coronary syndrome (ACS), potassium levels <3.5 mEq/L are associated with ventricular arrhythmias. Current guidelines therefore recommend a potassium target >4.0 mEq/L in ACS. Our study evaluated the association between potassium levels, cardiac arrhythmias, and cardiovascular death in patients with non-ST-segment elevation myocardial infarction or unstable angina. Potassium levels were measured in 6515 patients prior to randomization to receive either ranolazine or a placebo in the MERLIN-TIMI 36 trial. A seven-day continuous electrocardiographic assessment was obtained to determine the incidence of non-sustained ventricular tachycardia (NSVT) and ventricular pauses. The association between potassium levels and cardiovascular death was evaluated using a Cox proportional hazards regression model with multivariable adjustment. NSVT lasting for at least eight consecutive beats occurred more frequently at potassium levels <3.5 mEq/L than at potassium levels ⩾5 mEq/L (10.1 vs. 4.5%, p=0.03 for trend), whereas the inverse pattern was observed for ventricular pauses >3 s, which occurred more frequently at potassium levels ⩾5 mEq/L than at potassium levels <3.5 mEq/L (5.9 vs. 2.0%, p=0.03 for trend). There was a U-shaped relationship between the potassium level at admission and both early and late risk of cardiovascular death. Compared with patients with potassium levels of 3.5 to <4 mEq/L, a potassium level <3.5 mEq/L was associated with an increased risk of cardiovascular death at day 14 (2.4 vs. 0.8%, HRadj 3.1, p=0.02) and at one year (6.4 vs. 3.0%, HRadj 2.2, p=0.01). The risk of cardiovascular death at one year was also significantly increased at potassium levels ⩾4.5 mEq/L and a similar trend was noted at potassium levels ⩾5 mEq/L. The lowest risk of cardiovascular death was observed in patients with admission potassium levels between 3.5 and 4.5 mEq/L. Both lower and higher levels of potassium were associated with tachyarrhythmias and bradyarrhythmias, suggesting a potential mechanistic explanation for the increased risk of cardiovascular death at the extremes of potassium homeostasis.