Increased Dispersion of Ventricular Repolarization as an Arrhythmic Risk Marker in Drug-free Patients With Major Depressive Disorder: A Preliminary Comparative Study

Abstract

Objective: Drug-free patients with major depressive disorder (MDD) are understudied in terms of increased risk for arrhythmias. In this study, we compared changes in corrected QT interval (QTc), QTc dispersion (QTcd), Tpeak-Tend (Tp-e), Tp-e/QT ratio, corrected JT interval (JTc), and JTc dispersion (JTcd), which are considered to be among the risk factors for the emergence of ventricular arrhythmias in patients with MDD. Methods: The study involved 50 patients with MDD who had been free of psychotropic medications for at least 1 month and 52 age-matched and sex-matched healthy controls. Illness-related characteristics, including duration of illness and Beck Depression Inventory scores, were recorded. Electrocardiography recordings made under a standardized procedure were performed for all participants, and arrhythmia risk markers were calculated from the electrocardiograms. Results: The patient group had significantly higher QTcd, JTc, and JTcd values compared with the controls. Among electrocardiogram markers, only Tp-e/QTc was significantly and inversely correlated with the duration of illness, while none of the markers was associated with Beck Depression Inventory scores. Conclusions: Alterations in electrocardiogram-derived markers of ventricular arrhythmia, which can be obtained easily and inexpensively, can be evaluated for the prediction and prevention of severe cardiac conditions in patients with MDD and considered in selecting the safest antidepressant options available.

Effect of long-term combined use of antipsychotics on ventricular repolarization index

“…The normal range of TpTe is 80-100 ms, re ecting the degree of transmural dispersion of action potential repolarization between intracardiac and epicardial cells and M cells, [25][26][27][28][29]Antipsychotics drugs prolong ventricular repolarization time by inhibiting I Kr and thus reducing net outward currents, And the endocardial or epicardial repolarization rate slowed less than M cells, resulting in more signi cant T wave drop time, increased transwall discrete of action potential, and induced depolarization triggers TdP [30][31].TpTe ≥ 103.3 ± 17.4ms was considered to be prolonged [32]. In this study, the minimum and maximum mean values of male TpTes (117.18 ± 24.58 ~ 126.82 ± 29.14ms) exceeded the high limit, while the annual minimum and maximum mean values of female TpTes (115.29 ± 27.51 ~ 123.79 ± 33.59ms) exceeded the high limit.…”