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Three Part Question

In [patients presenting with supraventricular tachycardia] are [troponin levels] useful for [evaluating the presence of coronary artery disease]?

Clinical Scenario

A 54 year old female smoker with a history of hypertension presents to the emergency department with a complaint of heart fluttering and shortness of breath. Her vital signs reveal a blood pressure of 145/80, a pulse rate of 207, a respiratory rate of 18, and a pulse oximetry of 100% on room air. Her exam revealed tachycardia but it was otherwise within normal limits. An ECG was obtained and it revealed supraventricular tachycardia (SVT). While you treat the patient’s heart rate, you wonder if a troponin level would be useful in evaluating the presence of coronary artery disease.

Search Strategy

Medline (dates) using the Pubmed interface
[supraventricular tachycardia] AND [troponin levels] AND [evaluation of coronary artery disease]. Focused on related articles for PMID: 18022713 [PubMed - indexed for MEDLINE]. LIMIT to human and English language.

Search Outcome

103 articles found. 7 articles found to be relevant and are listed below.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Redfearn, et al. 2005 UK	3 patients ages 22-72 with SVT and elevated troponin levels.	Retrospective cohort.	Raised troponin I leading to coronary angiography:	All patients had normal coronary vessels on angiography. The 72 yo patient was also found to have evidence of hemodynamic compromise.	Limited patient group with no comparison group of patients with SVT and CAD. Database entry may have be retrospective and subject to bias.
Zellweger, M, et al. 2003 Switzerland	4 adult patients ages 44-57 with SVT and elevated troponins.	Case series.	Raised troponin I leading to subsequent testing for CAD	All patients were determined to not have CAD as ruled out by echocardiography with gated myocardial perfusion (1 patient), stress echocardiography (2 patients), and coronary angiogram (2 patients).	Limited case series.
Bakshi, T.K., et al 2002 New Zealand	3 patients ages 37-49 with SVT and elevated troponin levels.	Prospective cohort.	Consecutive patients with elevated troponins who underwent angiography for suspected coronary disease.	2 patients had high likelihood of ACS according to electrocardiographic changes and 1 patient had low likelihood on ECG. All patients were found to have normal coronary arteries on angiography.	Limited case series.
Miranda, RC, et al 2006 Brazil	49 year-old female with SVT	Case study.	Elevated troponin I level.	Patient was found to have normal coronary arteries on angiogram.	Limited case study.
Patanè, S, et al 2009 Italy	49 year-old female with SVT	Case study	Elevated troponin level without clinical or ECG presentation of ACS.	On echocardiography mitral regurge and mild interventricular septal hypertrophy were present. ECG did not reveal any significant changes.Patient recovered over several days with a return to baseline troponin I levels.	Limited case study.
Yeo, KK, et al. 2006 United States	3 patients ages 22-58 with SVT and elevated troponin levels.	Case series.	Elevated troponin I level.	All patients were found to have normal coronary arteries on coronary angiography.	Limited case series.
Kanjwal et al, 2008, USA	7 patients ages 18-67 with tachycardias (5 with SVTs) and elevated troponin levels.	Case series	All patients presented with chest comfort and elevated troponin levels and subsequently underwent coronary angiography.	All patients underwent coronary angiography and were found to have normal epicardial vessels. There was no evidence of hemodynamic instability in any of the patients.	Limited case series.

Comment(s)

Troponin levels have been of paramount importance in improving the sensitivity of acute coronary syndrome (ACS) detection. However, while elevated troponin levels are part of the criteria for the diagnosis ACS, it is not pathognomonic for the disease. Troponins have been shown to be elevated in a wide range of physiologic states such as sepsis, subarachnoid hemorrhage, and pulmonary embolism.. As a result, it is necessary that elevated troponin levels be evaluated in context of the whole clinical picture for individual patients. While troponin levels can be useful in a clinical situation suspicious for ACS, troponin elevations can also be misleading. This can cause both unnecessary tests and treatments to be ordered and also a delay in diagnosis and proper treatment. In a patient with SVT, the use of troponin testing would best be performed selectively based on presenting symptoms and risk factors for acute coronary syndrome. Routine testing will result in false positives as indicated in the literature review presented above. The patient presented above would not likely benefit from a troponin level unless her shortness of breath persisted even after the successful treatment of SVT.

Clinical Bottom Line

There has not been enough research to date to support the routine use of troponin levels in the evaluation of SVT. Having reviewed the evidence we do not recommend that troponin levels are taken in uncomplicated SVT patients.

References

1. Redfearn, et al. Supraventricular tachycardia promotes release of troponin I in patients with normal coronary arteries International Journal of Cardiology 2005; 521-522
2. Zellweger, M, et al. Elevated troponin levels in the abscence of coronary artery disease after supraventricular tachycardia Swiss Medical Weekly 2003; 439-441
3. Bakshi, T.K., et al. Causes of elevated troponin I in normal coronary angiogram Internal Medicine Journal 2002; 520-525
4. Miranda, RC, et al. Elevated troponin levels after prolonged supraventricular tachycardia in patient with normal coronary angiography Cardiology 2006; 106
5. Patanè, S, et al Abnormal troponin levels after supraventricular tachycardia Internal Journal of Cardiology 2009; 57-59
6. Yeo, KK, et al Tachycardia-induced elevation in cardiac troponin in the abscence of coronary artery disease Hawaii Medical Journal 2006; 86-87
7. Kanjwal K, Imran N, Grubb B, et al. Troponin elevation in patients with various tachycardias and normal epicardial coronaries. Indian Pacing Electrophysiology Journal. 2008;8(3):172-4.