Sodium channel blocker toxicity

Sodium channel blocker toxicity causes a wide QRS and a terminal R wave in aVR >3mm or R:S >0.7. There is a risk of seizures and ventricular arrhythmias. Examples of sodium channel blockers include Tricyclic antidepressants (TCA), Type Ia and Ic antiarrhythmics, local anaesthetics, antimalarials, propranolol, carbamazepine and quinine. It is also known as TCA overdose

Featured Example

References

ECG Library (13)

Sort by:
TitleDate
ASCDESC
Show:
31230
Columns:
In the ECGquest archives, this ECG has been tagged with: - 12-Lead R in aVR Wide QRS Sodium channel blocker toxicity ECG of the Week CC-BY-NC-SA
ECG of the Week – 18th February 2019 – Interpretation 29569

This ECG is from a man in his 60s who presented following a dothiepin overdose.

This ECG shows wide QRS with R in aVR and RBBB morphology, caused by sodium channel toxicity.

In the ECGquest archives, this ECG has been tagged with: - Seizure 12-Lead R in aVR Wide QRS Normal Sinus Rhythm Sodium channel blocker toxicity Dr Smith's ECG Blog CC BY-NC
Bupropion Overdose Followed by Cardiac Arrest and, Later, ST Elevation. Is it STEMI? 8 hours later. 26623

This ECG is from a young woman who presented with status epilepticus seizures and an apparent overdose of bupropion, with possible cocaine ingestion. She was intubated and given propofol and benzodiazepines, which terminated the seizures. This was the repeat ECG 8 hours after presentation, just before she arrested.

In the ECGquest archives, this ECG has been tagged with: - Cardiac arrest 12-Lead R in aVR Tachycardia Wide QRS Sodium channel blocker toxicity Dr Smith's ECG Blog CC BY-NC
Bupropion Overdose Followed by Cardiac Arrest and, Later, ST Elevation. Is it STEMI? Post arrest ECG 26626

This ECG is from a young woman who presented with status epilepticus seizures and an apparent overdose of bupropion, with possible cocaine ingestion. She was intubated and given propofol and benzodiazepines, which terminated the seizures. This was the repeat ECG 8 hours after presentation, just after she had a PEA arrest that resolved with epinephrine and bicarbonate.