Posted by ed_uk on January 26, 2005, at 14:15:22
In reply to Re: Nortriptyline » ed_uk, posted by jujube on January 25, 2005, at 23:09:51
J Clin Psychiatry. 1993 Feb;54 Suppl:16-22.
Review of the cardiovascular effects of heterocyclic antidepressants.
Glassman AH, Preud'homme XA.
Department of Clinical Psychopharmacology, New York State Psychiatric Institute, NY 10032.
We review the effects of heterocyclic antidepressant compounds on the cardiovascular system. It has been shown that tricyclic antidepressants (TCAs) slow intraventricular conduction, and this can be seen on a standard ECG as the increased QRS, PR, and QTc intervals. This prolonged conduction is dangerous to patients in two conditions. In overdose, delayed conduction may lead to a complete heart block or ventricular reentry arrhythmias. Either of these complications, or a combination of both, may lead to death. When treated with TCAs at therapeutic plasma levels, depressed patients with preexisting conduction disease, particularly bundle-branch block, are at higher risk to develop symptomatic A-V block than depressed patients free of conduction disorders. Clinically, the effects of TCAs on conduction does not differ significantly within the family of drugs. Who gets complications is much more a function of severity of the patient's preexisting cardiac condition. The most common cardiovascular effect of TCAs is orthostatic hypotension. Postural hypotension is more dangerous in elderly patients because it may lead to falls that cause serious physical injuries. Severe orthostatic hypotension is more likely to develop in depressed patients with left ventricular impairment and/or in patients taking other drugs like diuretics or vasodilators. ***Nortriptyline has been shown to cause significantly less serious postural blood pressure drops, an important difference between this drug and other TCAs.*** Another cardiovascular effect of TCAs is that they reduce ventricular arrhythmias. They share this property with Type 1A antiarrhythmic compounds, and a variety of Type 1 antiarrhythmics have recently been shown to increase mortality in postmyocardial infarction patients.
Clin Geriatr Med. 1992 May;8(2):323-34.Using tricyclic antidepressants in the elderly.
McCue RE.
Department of Psychiatry, Beth Israel Medical Center, New York, New York.
Only a few of the eight tricyclic antidepressants available today have been studied systematically in the elderly. Tertiary amine tricyclics such as amitriptyline and imipramine have been reported to be effective in depressed geriatric patients, but because of their potential for side effects, it is not advisable to use them in the elderly. Desipramine has a less toxic side effect profile, especially with respect to anticholinergic effects, but its efficacy has not been well studied. This does not mean, however, that it is not an effective drug for the elderly depressed. Nortriptyline is the tricyclic that has been the most studied. The results of those studies show that it should be recommended as an antidepressant for older patients. It is effective in both the acute and continuation treatment of depression in the elderly. As far as its use in maintenance treatment, the results are mixed but at this moment there is nothing with which to compare it. It has a favorable side effect profile: low anticholinergic activity; relatively few cardiac side effects, even in patients with preexisting cardiac disease; and ***relatively less orthostatic hypotension.*** Nortriptyline also has the virtue of an established therapeutic range for its steady-state plasma level. The role of its 10-hydroxy metabolite needs to be further explored, but when its contribution to efficacy and toxicity is better understood, it may be possible to use nortriptyline in a more precise and safe way in elderly patients. The bulk of evidence suggests, partly by default, that nortriptyline should probably the tricyclic-of-first-choice in treating an elderly patient with major depression.
Psychopharmacology (Berl). 1981;74(4):360-4.
Cardiovascular effect of imipramine and nortriptyline in elderly patients.
Thayssen P, Bjerre M, Kragh-Sorensen P, Moller M, Petersen OL, Kristensen CB, Gram LF.
Cardiovascular effects in elderly depressed patients (age 62-78 years) treated with imipramine (N = 11) or nortriptyline (N = 10) were recorded by monitoring of heart rate, blood pressure, systolic time intervals, standard ECG and 24-h ECG. The two drugs exhibited distinctly different cardiovascular reactions. The use of imipramine was severely limited by orthostatic hypotension occurring at subtherapeutic plasma levels, which resulted in falls with fracture in two patients. In contrast, ***nortriptyline at therapeutic drug levels did not significantly influence orthostatic blood pressure regulation.*** Nortriptyline caused moderate changes in systolic time intervals, indicating impairment in myocardial contractility. This effect was not seen with imipramine, but a majority of the patients did not reach therapeutic plasma levels because of blood pressure reactions. Neither imipramine nor nortriptyline induced changes in cardiac conduction time measurements or arrhythmias. In addition to the blood pressure reactions, the use of imipramine was complicated by dose dependent kinetics.
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thread:445244
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