Unusual case of severe arrhythmia developed after acute intoxication with tosylchloramide

Abstract

Background: Drugs not commonly considered to be cardioactive agents may cause prolongation of the QT interval with resultant torsades de pointes and ventricular fibrillation. This form of drug toxicity often causes cardiac arrest or sudden death.

Case presentation: After accidental ingestion of tosylchloramide a caucasian 77-year-old woman, with a family history of cardiovascular disease and hypertension, was admitted to the intensive care unit following episodes of torsades de pointes with a prolonged QT/QTc interval (640/542 ms). The patient received an implantable cardioverter-defibrillator, was discharged from the hospital with normal QT/QTc interval and did not experience additional ventricular arrhythmias during one year of follow-up.

Conclusion: This is the first report concerning an unusual case of torsades de pointes after accidental intoxication by ingestion of tosylchloramide. The pronounced impact of the oxidyzing agent tosylchloramide on the activity of some of the ion channels regulating the QT interval was identified as a probable cause of the arrhythmia.

Figure 1

TDP with fast degeneration into Ventricular Fibrillation. The ECG-strip pre-TDP (Figure1A) shows a QT interval of 640 msec (QTc is 542 msec).

Figure 2

ECG at the admission to ICU shows a LBBB with a prolonged QT/QTc interval (640–542 msec).

Figure 3

Coronary Angiography. No significant CAD is detected in right cororary artery. The middle left anterior descending coronary artery had a non-significant stenosis (< 50%), as confirmed by IVUS control.

Figure 4

ECG at hospital discharge. QT interval measures 400 msec, the QTc interval 430 msec.

Figure 5

ECG at 1-year follow-up shows stable LBBB and normal QT/QTc interval (405/432 msec).