Mehmet TÜRE, Meki BİLİCİ, Alper AKIN, Fikri DEMİR, Hasan BALIK, Savaş Mert DARAKÇI

Complete atrioventricular block associated with clozapine intoxication: case report

Clozapine is one of the atypical anti-psychotic drugs used in the treatmentof resistant schizophrenia. Although cardiac side-effects are rare, it has beenreported that there may be development of myocarditis, dilated cardiomyopathy,postural orthostatic hypotension and prolonged QT duration. Completeatrioventricular (AV) block is characterized by the inability to transmit allof the atrial signal to the ventricles. Causes may be congenital, idiopathicor acquired which are associated with surgery, infection, or muscle disease.AV block is extremely serious and permanent pacemaker insertion is usuallynecessary for all patients. Complete AV block may develop due to clozapineintoxication through increase in vagal tonus, sinoatrial node (SN) and theinhibition of atrioventricular node signalling. The case presented here is of a15-year old female patient who developed AV total cardiac block associatedwith the taking of clozapine in a suicide attempt.

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