2024年11月30日 · The ECG is a vital tool in the prompt diagnosis of poisoning with sodium-channel blocking medications such as tricyclic antidepressants (TCA), which cause CNS and cardiovascular toxicity in overdose in the form of seizures and ventricular dysrhythmias.

Inhibition of presynaptic neurotransmitter reuptake (norepinephrine and serotonin) is the primary mechanism for the therapeutic effects of tricyclic antidepressants (TCAs). Following overdose, the following cellular effects often produce important clinical consequences: Blockade of cardiac fast sodium channels.

Pre-intubation and on arrival it is vital to get an ECG looking for signs of toxicity (widening of the QRS, large terminal R wave in aVR increased R/S ratio (>0.7) in aVR and QT prolongation).

2009年9月26日 · Discuss the classic EKG findings of tricyclic antidepressant cardiotoxicity (TCA). Formulate an empiric treatment regimen based on EKG findings. Summarize the relevance of EKG findings in the overdosed patient.

2021年4月26日 · Tricyclic antidepressants (TCAs) are the perhaps the most widely discussed intoxicant which inhibits sodium channels (causing a characteristic pattern of QRS widening with a tall R-wave in aVR). However, a broad variety of other xenobiotics also block sodium channels, causing a similar pattern of findings.

2018年3月22日 · What are the main ECG pointers for TCA overdose? Cardiac toxicity can develop quickly in TCA overdose, so get an ECG early in the clinical course if suspecting the diagnosis; The pattern of ECG findings in TCA overdose includes: tachycardia, prolonged QRS duration, long QT interval, rightward axis deviation and wide R-wave in aVR

2022年5月7日 · 12-lead ECG: TCA toxicity causes serious and potentially fatal arrhythmias. Typical ECG findings include widened QRS and prolonged QTc (Figure 1). Patients with an abnormal initial ECG are at risk of progressing to VF and VT

2008年1月24日 · Patients presenting TCA overdose should be treated with great care and a high index of suspicion, particularly if the symptoms are progressive. Challenging EKG and 12-lead ECG cases reviewed...

2024年12月18日 · A QRS duration >100 ms suggests blockade of cardiac fast sodium channels. In combination with right axis deviation of the terminal QRS, it is virtually pathognomonic (see Figure 2.20.3). Most studies examine ECG changes in TCA intoxication and are small or retrospective. However, the following appear to be associated with major toxicity:

This document discusses the electrocardiogram (EKG) findings associated with tricyclic antidepressant (TCA) toxicity. It notes that TCAs can cause: 1) Sodium channel blockade leading to prolonged PR and QRS intervals and ventricular dysrhythmias. 2) Potassium channel inhibition causing prolonged QTc intervals.