Key Points
- To evaluate clinical variables and characterize electrocardiographic changes in patients presenting with tricyclic antidepressant poisoning.
- Analyzed clinical variables, hemodynamic changes, and electrocardiograms in 153 patients with tricyclic antidepressant poisoning (mean age 34 years; amitriptyline involved in 73% of cases with an average dose of approximately 1,000 mg).
- Assessed correlations between poisoning severity indicators (dose, blood pressure, coma duration) and ECG parameters, including heart rate, QRS interval, QT time, and PQ time.
- Admission systolic blood pressure was significantly lower (p < 0.001) and heart rate was significantly higher (p < 0.001) than at ward discharge, with tachycardia (≥ 90 beats/min) present in 73% of cases.
- The most characteristic ECG finding was QRS prolongation (≥ 0.11 sec) in 42% of patients (mean QRS duration 0.11 sec), while QT prolongation occurred in approximately 42% and prolonged PQ time in 28%.
- QRS duration was not correlated with heart rate but was strongly related to poisoning severity; five patients (3.3%) died, each presenting with arrhythmias and marked QRS widening (mean 0.19 sec).
Structured PICO
PPopulation153 patients with tricyclic antidepressant (TCA) poisoning, mean age 34 years.
OOutcomeRelation of clinical variables to ECG changes (specifically QRS prolongation)surrogate
In tricyclic antidepressant poisoning, QRS prolongation is a valuable guide to the severity of poisoning and risk of cardiac complications.