Valentino Michael A, Panakos Andrew, Ragupathi Loheetha, Williams Janna, Pavri Behzad B
Division of Cardiology, Thomas Jefferson University Hospital, 925 Chestnut St. Mezzanine, Philadelphia, PA, 19107, USA.
Division of Internal Medicine, Thomas Jefferson University Hospital, 833 Chestnut Street Suite 701, Philadelphia, PA, 19107, USA.
Cardiovasc Toxicol. 2017 Jul;17(3):260-266. doi: 10.1007/s12012-016-9380-0.
In the setting of flecainide toxicity, supraventricular tachycardia can manifest as a bizarre right or left bundle branch block, sometimes with a northwest axis, and can easily be mistaken for ventricular tachycardia leading to inappropriate therapy. We conducted a comprehensive literature review for cases of flecainide toxicity. We found 21 articles of flecainide toxicity in adult patients in which 22 ECG tracings were published. In patients with flecainide toxicity and QRS duration ≤ 200 ms, the ECGs were more likely to show RBBB, visible P waves (p = 0.03), and shorter QT (p = 0.02) and QTc intervals (p = 0.004). With QRS duration > 200 ms, the ECGs were more likely to show LBBB, loss of P waves, a northwest axis (p = 0.01), and longer QT and QTc intervals. Deaths were reported only in patients with QRS duration >200 ms, and the outcome of death or requirement for mechanical circulatory support was more prevalent in patients with a QRS duration > 200 ms [2/13 (15.4 %) vs. 6/10 (60 %), p = 0.04]. In patients with access to the medication, flecainide toxicity should be suspected with: (1) broad QRS, (2) RBBB morphology with QRS ≤ 200 ms; RBBB or LBBB morphology with QRS ≥ 200 ms (3) HR out of proportion to the degree of hemodynamic instability. The duration of the QRS interval is prognostic, with mortality and the requirement for mechanical circulatory support being more common in patients with a QRS > 200 ms.
在氟卡尼中毒的情况下，室上性心动过速可表现为奇异的右或左束支传导阻滞，有时伴有电轴西北偏，很容易被误诊为室性心动过速，从而导致不适当的治疗。我们对氟卡尼中毒病例进行了全面的文献综述。我们发现了21篇关于成年患者氟卡尼中毒的文章，其中发表了22份心电图描记。在氟卡尼中毒且QRS时限≤200 ms的患者中，心电图更有可能显示右束支传导阻滞、可见P波（p = 0.03）、QT间期较短（p = 0.02）和QTc间期较短（p = 0.004）。当QRS时限>200 ms时，心电图更有可能显示左束支传导阻滞、P波消失、电轴西北偏（p = 0.01）以及QT和QTc间期较长。仅在QRS时限>200 ms的患者中报告了死亡病例，死亡或需要机械循环支持的结局在QRS时限>200 ms的患者中更为普遍[2/13（15.4%）对6/10（60%），p = 0.04]。对于能够接触到该药物的患者，若出现以下情况应怀疑氟卡尼中毒：（1）QRS波增宽；（2）QRS≤200 ms时呈右束支传导阻滞形态；QRS≥200 ms时呈右束支传导阻滞或左束支传导阻滞形态；（3）心率与血流动力学不稳定程度不成比例。QRS间期的时长具有预后意义，QRS>200 ms的患者死亡率更高且更常需要机械循环支持。
