title: Effects of nortriptyline and paroxetine on QT variability in patients with panic disorder.
abstract: This study investigated beat-to-beat QT variability in patients with panic disorder before and after treatment with nortriptyline (n = 13) and paroxetine (n = 16), using an automated algorithm to compute QT intervals. An increase in QT variability appears to be associated with symptomatic patients with dilated cardiomyopathy and also with an increased risk for sudden cardiac death. QTvi (QT variability index: a log ratio of QT variance normalized for mean QT over heart rate variability normalized for mean heart rate) was significantly higher in supine posture in patients with panic disorder treated with nortriptyline (P = 0.006) but not paroxetine. Thus paroxetine may be a better drug of choice especially in patients with coexisting cardiac disease. These findings are important especially in view of the recent reports of increased risk for cardiovascular mortality and sudden death in patients with anxiety and depression. QTvi can be a valuable noninvasive measure of temporal repolarization lability, especially to study the side effects of medications which affect cardiac autonomic function.
authors.affiliation: Department of Psychiatry, Wayne State University School of Medicine, Detroit, Michigan, USA.
authors.forename: V K
authors.initials: VK
authors.lastname: Yeragani
authors.forename: R
authors.initials: R
authors.lastname: Pohl
authors.forename: V C
authors.initials: VC
authors.lastname: Jampala
authors.forename: R
authors.initials: R
authors.lastname: Balon
authors.forename: C
authors.initials: C
authors.lastname: Ramesh
authors.forename: K
authors.initials: K
authors.lastname: Srinivasan
mesh_terms: D000328:Adult; D000929:Antidepressive Agents, Tricyclic / Q000009:adverse effects* / Q000627:therapeutic use; D016757:Death, Sudden, Cardiac / Q000209:etiology; D004562:Electrocardiography / Q000187:drug effects*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008133:Long QT Syndrome / Q000139:chemically induced* / Q000175:diagnosis; D008297:Male; D009661:Nortriptyline / Q000009:adverse effects* / Q000627:therapeutic use; D016584:Panic Disorder / Q000188:drug therapy* / Q000523:psychology; D017374:Paroxetine / Q000009:adverse effects* / Q000627:therapeutic use; D012307:Risk Factors; D017367:Selective Serotonin Reuptake Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use
chemical_list: D000929:Antidepressive Agents, Tricyclic; D009661:Nortriptyline; D017374:Paroxetine; D017367:Selective Serotonin Reuptake Inhibitors