Keywords: tachycardia, SVT, PSVT, troponin, laboratory (PubMed Search)
Paroxysmal supraventricular tachycardia (PSVT) is a common tachydysrhythmia encountered in ED practice. PSVT in itself has not been found to be an isolated manifestation of myocardial infarction or unstable angina (i.e. "isolated" = in the absence of other concerning symptoms, such as anginal-type pain, etc.). Nevertheless, some physicians will routinely test cardiac troponin levels to evaluate for ACS in these patients. We should all remember, though, that tachydysrhythmias including PSVT are a potential cause of elevated troponin levels in the absence of coronary disease, and these elevations do NOT correlate with adverse outcomes unless other concerning symptoms/signs are present as well.
A recent study1 corroborated this point: 11 out of 38 patients with PSVT had a positive troponin level. Only 2 of the 11 ruled in for ACS, and all of the patients were well at 30 days. Both patients presented with hypotension (SBP in the 70s) and also had other concerning symptoms, such as chest pain (both), dizziness (both), and dyspnea (one).
The takeaway point is simple: if you routinely send troponin levels on your patients for PSVT in the absence of other concerning symptoms/signs, you'll find yourself chasing a lot of false-positive levels.
Carlberg DJ, Tsuchitani S, Barlotta KS, Brady WJ. Serum troponin testing in patients with paroxysmal supraventricular tachycardia: outcome after ED care. Am J Emerg Med 2011;29:545-548.