A 44-year-old man is brought to the emergency department following a collapse and suspected deliberate self-poisoning.
DESCRIPTION:
- Ventricular rate 102 bpm
- Sinus rhythm
- PR interval 194 ms
- QRS axis (29°)
- QRS duration 128 ms
- R’ wave in aVR > 3 mm
- QTc 505 ms
INTERPRETATION:
- Sinus tachycardia
- Interventricular conduction delay – QRS duration > 100 ms in lead II
- Terminal R wave (R’) in aVR > 3 mm
What agents could potentially be responsible?
DESCRIPTION:
- Ventricular rate 100 bpm
- Sinus rhythm
- PR interval 194 ms
- QRS axis (-67°)
- QRS duration 138 ms
- R’ wave > 3 mm and R/S ration > 0.7 in aVR
- QTc 518 ms
INTERPRETATION:
- Progressive and worsening sodium channel blockade.
- Collateral history revealed patient was prescribed dothiepin.
- Shortly after this ECG was taken the patient had a generalised tonic-clonic seizure, however with subsequent effective management of tricyclic antidepressant (TCA) poisoning the patient made a complete recovery.
See LITFL for further information on the electrocardiographic features of TCA overdose.
