Conclusions
Prolongation of the QT interval by a non cardiovascular drug including notably an antipsychotic agent is considered a good marker of the arrythmogenic potential of that agent [1].
Psychiatric patients had been identified as a population at risk for cardiovascular problems [12,25]. Mortality rates are higher in psychiatric patients than in the general population [26] and the pharmacological treatment itself might produce side effects that affect mortality from causes other than suicide [27].
There is a vast amount of evidence available showing the effect of a single antipsychotic on QTc interval however there is not much evidence obtained for clinical populations treated with a different combinations of drugs.
Interestingly, the response to repolarization prolonging stimuli is "patient-specific" [9]. Thus, detecting the patients with a reduced repolarization reserve [28,29] will lead to personalized psychotropic therapy according to the predisposition of that patient to develop cardiac side effects with a certain drug.
In view of the fact that psychiatric patients are considered high risk subjects and since they frequently show electrolytes unbalances [30], an accurate monitoring of the QTc interval before and after the beginning of treatment appears warranted, particularly for patients taking multiple psychoactive drugs, sharing QTc prolonging properties.
Further observational studies on larger samples of patients, comparing QTc intervals, plasmatic levels of antipsychotics and daily doses of psychotropic drugs are necessary to perform statistical comparisons for each kind of antipsychotic and for each kind of antipsychotic-antidepressant association commonly used in clinical practice.