Electrocardiographical P wave changes after electroconvulsive therapy in patients with schizophrenia: a preliminary study

Cardiac ventricular conduction has been studied in patients with schizophrenia who have undergone electroconvulsive therapies while they were drug-naive or drug-free or on drug regimens; however, atrial conduction has not been studied in this setting. We aimed to measure atrial and ventricular conduction changes in hospitalized patients with schizophrenia after convulsive therapy.

Fifteen people with schizophrenia and 15 healthy people enrolled in the study. The participants were assessed for fasting blood glucose and electrolyte levels before the study. All patients were receiving atypical antipsychotics. The electrocardiography records were obtained before the first convulsive therapy and after the third session.

The baseline P minimum duration in the patient group was significantly smaller than healthy controls. There was a significant increase in patients' P maximum duration after the third convulsive therapy session (P < 0.05). The differences in P Wave Dispersion, QTc, and QT Dispersion between baseline and after the third session in patients were not statistically significant (P > 0.05).

The lower P wave duration minimum may be related to autonomic nervous system dysregulation in schizophrenia because an acute episode of the illness and/or antipsychotic drugs. In addition, we propose that electroconvulsive therapy alone or in combination with atypical antipsychotics may influence atrial conduction as evidenced by the significantly prolonged P wave maximum.