The importance of ECG monitoring in antidepressant treatment

The TCA efficacy in the treatment of depressive illness is well established. Cardiac side effects, however, present serious disadvantages in TCA therapy, and are a risk particularly for the elderly and for all age groups of patients with pre-existing heart disease and in overdose. The SSRIs a newer class of antidepressant drugs seem to be effective antidepressants with an improved tolerability compared to TCAs. However, they have been far less studied than the TCAs. To evaluate the effect of citalopram, a SSRI, on cardiac function assessed by ECG recordings, a retrospective analysis of 3746 ECGs obtained in European clinical trials was performed. Pre-treatment ECGs were compared to ECGs from treatment periods. The results differed from the established TCA effects on the ECG. Citalopram reduced heart rate within the first weeks of treatment, without further reduction in the treatment period. The PO interval and QRS values were largely unaltered. Citalopram treatment was associated with insignificant influence and prolongation of QT interval. ECGs with pre treatment prolongation of QTc showed no aggravation during citalopram treatment. Ventricular extra-systoles were the most prominent arrhythmia in QTc prolongation (5%). Adverse even reports related to citalopram treatment and overdose showed no increased risk of cardiac deterioration or death.Conclusion: Citalopram seems, in contrast to TCAs, to be free from significant cardiac side effects also in patients with existing heart disease. ECG monitoring is frequently recommendable in TCA treatment, while citalopram treatment can be carried out safely without ECG control.