多巴酚丁胺负荷超声心动图：血钾水平异常对心律失常的影响

Bird Jared G, McCully Robert B, Pellikka Patricia A, Kane Garvan C

Division of Cardiovascular Ultrasound, Department of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.

J Am Soc Echocardiogr. 2017 Jun;30(6):595-601. doi: 10.1016/j.echo.2017.01.017. Epub 2017 Apr 7.

BACKGROUND

Guidelines suggest that an abnormal blood potassium level is a relative contraindication to performing dobutamine stress echocardiography (DSE). However, this has not been previously studied.

METHODS

We reviewed a consecutive series of patients who had potassium testing within 48 hours of undergoing DSE for the evaluation of myocardial ischemia over a 10-year period (N = 13,198). Normal potassium range in our laboratory is 3.6-5.2 mmol/L. Hemolyzed samples were not included. The association of potassium levels with the development of supraventricular and ventricular arrhythmias was assessed.

RESULTS

The incidence of clinically significant arrhythmias was very low (supraventricular tachycardia/atrial fibrillation, 4.9%; nonsustained ventricular tachycardia, 2.9%; sustained ventricular tachycardia or ventricular fibrillation, 0.1%), confirming the overall safety of DSE. Most arrhythmias (88%) occurred in patients with normal potassium levels, and arrhythmia rates remained low in patients with potassium abnormalities. Patients with hyperkalemia had a lower risk of developing mild (odds ratio [OR], 0.39; 95% CI, 0.22-0.71) and severe (OR, 0.13; 95% CI, 0.01-0.68) supraventricular arrhythmias as well as mild ventricular arrhythmias (OR, 0.58; 95% CI, 0.40-0.83). Even though events were rare, patients with severe hypokalemia (potassium levels ≤ 3.1 mmol/L) had an increased risk of supraventricular arrhythmia and ventricular ectopy.

CONCLUSIONS

DSE is safe even in the setting of abnormalities in blood potassium concentrations, and hence cancellation of DSE in patients with potassium abnormalities does not appear warranted. Elevated potassium levels are associated with lower rates of clinically significant supraventricular and ventricular arrhythmias. While remaining at relatively low risk, patients with very low potassium levels (≤3.1 mmol/L) at the time of DSE have a modestly increased risk of arrhythmia. Consideration could be given to correcting severe hypokalemia prior to DSE.

背景

指南指出血钾水平异常是进行多巴酚丁胺负荷超声心动图（DSE）的相对禁忌证。然而，此前尚未对此进行过研究。

方法

我们回顾了在10年期间内连续接受DSE检查以评估心肌缺血且在检查前48小时内进行过血钾检测的患者系列（N = 13198）。我们实验室的正常血钾范围是3.6 - 5.2 mmol/L。不包括溶血样本。评估血钾水平与室上性和室性心律失常发生之间的关联。

结果

具有临床意义的心律失常发生率非常低（室上性心动过速/心房颤动，4.9%；非持续性室性心动过速，2.9%；持续性室性心动过速或心室颤动，0.1%），证实了DSE的总体安全性。大多数心律失常（88%）发生在血钾水平正常的患者中，血钾异常患者的心律失常发生率仍然较低。高钾血症患者发生轻度（优势比[OR]，0.39；95%置信区间，0.22 - 0.71）和重度（OR，0.13；95%置信区间，0.01 - 0.68）室上性心律失常以及轻度室性心律失常（OR，0.58；95%置信区间，0.40 - 0.83）的风险较低。尽管事件罕见，但严重低钾血症（血钾水平≤3.1 mmol/L）患者发生室上性心律失常和室性早搏的风险增加。