Journal of Research in Pharmacy Practice

ST‑T segment changes in patients with tricyclic antidepressant poisoning

Document Type : Original Article

Authors

. Farzad Gheshlaghi 1
. Mozhgan Karbalayi Mehrizi 2
. Ahmad Yaraghi 1
. Ali Mohammad Sabzghabaee 3
. Forough Soltaninejad 4
. Nastaran Eizadi-Mood 1

1 Department of Clinical Toxicology, Isfahan University of Medical Sciences, Isfahan, Iran

2 Department of Toxicology, Noor General University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran

3 Isfahan Clinical Toxicology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

4 Department of Pulmonary, Shahrekord University of Medical Sciences, Shahrekord, Iran

Abstract
Objective: Tricyclic antidepressant (TCA) poisoning is among highly prevalent and potentially 
dangerous toxicities. ST‑T changes are observed in the electrocardiogram (ECG) of most 
of TCA poisoned patients. We aimed to study ST‑T segment changes in TCA toxicity and 
its probable relationship with other ECG findings.
Methods: This retrospective study was carried out in Noor and Ali Asghar University 
Hospital, Isfahan (Iran) in 2012. Patients with TCA toxicity based on the patients’ history 
who had not consumed any cardio-active drugs and did not have a past medical history of 
cardiovascular disease in the recent 5 years, were randomly selected and investigated. Their 
demographic and medical data on admission including ECG, age, sex, type and amount of 
ingested TCA, poisoning severity score, QRS changes, QT interval, heart axis position and 
R‑wave were all recorded. ST‑T changes and their relation with other ECG parameters have 
been determined using statistical analysis.
Findings: Medical records of 272 patients were analyzed. In symptomatic patients, ST change 
prevalence was 40.8% and T change prevalence was 9.5%. In asymptomatic patients, the 
frequency of ST and T changes were 4.8% and 0.8%, respectively (P < 0.05). The most common 
ST and T changes in baseline (on admission) ECG were non‑significant elevation (15.4%), 
significant elevation (11%) in pre‑cordial leads, and T‑wave flattening (6.6%). A statistically 
significant correlation was documented between ST segment changes with QRS and R‑wave 
in aVR. The correlation between T‑wave changes and R‑wave in aVR lead was also significant.
Conclusion: ST‑T changes in TCA poisoned patients are more prevalent in symptomatic 
patients. Obviously for a more definite conclusion, it is necessary to design a prospective study 
with the control group. This may facilitate a better understanding of ST‑T segment changes.

Keywords

Electrocardiogram
poisoning
toxicity
tricyclic antidepressant

1. Wing YK. Recent advances in the management of depression 
and psychopharmacology. Hong Kong Med J 2000;6:85‑92.
2. Bebarta VS, Maddry J, Borys DJ, Morgan DL. Incidence 
of tricyclic antidepressant‑like complications after 
cyclobenzaprine overdose. Am J Emerg Med 2011;29:645‑9.
3. Choy CH, KitchellAK, KamCW. Lethal tricyclic antidepressant 
overdose. Hong Kong J Emerg Med 2001;8:101‑5.
4. Dart RC, Caravati EM, McGuigan MA. Medical Toxicology, 
3rd ed. Philadelphia: Lippincott Williams and Wilkins; 2004. 
p. 1914.
5. Kobayashi K, Miyajima M, Tanaka T, Kumagai K, Hirose Y, 
Hori Y, et al. Tricyclic antidepressant overdose rescued by 
percutanenous cardiopulmonary support: Report of two cases. 
Chudoku Kenkyu 2011;24:46‑50.
6. Burns E. Tricyclic overdose (sodium‑channel blocker toxicity). 
Available from: http://www.lifeinthefastlane.com/ecg‑library/
basics/tca‑overdose/. [Last accessed on 2013 Sep 07].
7. Fasoli RA, Glauser FL. Cardiac arrhythmias and ECG 
abnormalities in tricyclic antidepressant overdose. Clin Toxicol 
1981;18:155‑63.
8. Kiran HS, RavikumarYS, Jayasheelan MR, Prashanth. Brugada 
like pattern in ECG with drug overdose. J Assoc Physicians 
India 2010;58:120‑2.
9. Rechlin T. Decreased R‑R variation: Acriterium for overdosage 
of tricyclic psychotropic drugs. Intensive Care Med 
1995;21:598‑601.
10. Liebelt EL, Francis PD, Woolf AD. ECG lead aVR versus 
QRS interval in predicting seizures and arrhythmias in 
acute tricyclic antidepressant toxicity. Ann Emerg Med 
1995;26:195‑201.
11. Taherinia A, Heidarpour A. ST elevation in tricyclic 
antidepressants toxicity: A case report. Iran Heart J 
2012;13:43‑5.
12. Yanowitz FG. ST segment abnormalities. Available from: http//
www.library.med.utah.edu/kw/ecg/ecg_ outline/Lesson10/
index.html. [Last accessed on 2013 Sep 07].
13. Daviglus ML, Liao Y, Greenland P, Dyer AR, Liu K, Xie X, 
et al. Association of nonspecific minor ST‑T abnormalities with 
cardiovascular mortality: The Chicago Western Electric Study. 
JAMA 1999;281:530‑6.
14. Masoumi G, Eizadi‑Mood N, Akbari M, Sohrabi A, 
Khalili Y. Pattern of poisoning in Isfahan. J Isfahan Med Sch 
2012;29:2003‑10.
15. Persson HE, Sjöberg GK, Haines JA, Pronczuk de Garbino J. 
Poisoning severity score. Grading of acute poisoning. J Toxicol 
Clin Toxicol 1998;36:205‑13.
16. Shah VN, Karavadara NR, Shah DS, Shah BK. 
Gatifloxacin‑induced prolongation of QTc interval. Research 
letter. Indian J Pharmacol 2006;38:60‑1.
17. Micro EKG‑Mad scientist software. Available from:http://www.
madsci.com/manu/ekg_part.htm#The_ST_Segment. [Last 
accessed on 2013 Sep 07].
18. Dianat S, Zarei MR, Hassanian‑Moghaddam H, 
Rashidi‑Ranjbar N, Rahimian R, Rasouli MR. Tricyclic 
antidepressants intoxication in Tehran, Iran: Epidemiology 
and associated factors. Hum Exp Toxicol 2011;30:283‑8.
19. Prutkin JM. ECG tutorial: ST and T wave changes. 
In: Goldberger AL, editors. UpToDate. Waltham, MA: 
UpToDate; 2013.
20. Chan CY, Waring WS. Images in cardiovascular medicine. 
Tricyclic cardiotoxicity treated with sodium bicarbonate. 
Circulation 2007;115:e63‑4.
21. Sigurdsson E, Sigfusson N, Sigvaldason H, Thorgeirsson G. 
Silent ST‑T changes in an epidemiologic cohort study – A 
marker of hypertension or coronary heart disease, or both: The 
Reykjavik study. J Am Coll Cardiol 1996;27:1140‑7.
Journal of Research in Pharmacy Practice
Volume 2, Issue 3
Summer 2013
Pages 110-113

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