B-PO04-158 TROPONIN ELEVATION DURING EPISODES OF SUPRAVENTRICULAR TACHYCARDIA

Abstract

Patients presenting to the emergency room with episodes of supraventricular tachycardia (SVT) frequently have signs and symptoms of an acute coronary syndrome, including chest pain, ischemic EKG changes, and a mildly elevated serum troponin. Case reports and small studies have shown that in such cases the likelihood of obstructive coronary artery disease (CAD) is low but the true incidence is unknown. To quantify the risk of obstructive CAD in patients who are found to have an elevated serum troponin at the time of an episode of SVT. In a series of 696 successive patients referred for catheter ablation, we retrospectively studied the clinical outcomes of 180 patients who had their troponin-I (TnI) level measured immediately after an episode of SVT. There were 98 patients whose TnI level was normal (<0.03). Of these, 48 underwent stress testing and 12 underwent coronary angiography (CAG) but none had obstructive CAD. There were 53 patients whose TnI was in the indeterminate range (0.03 to <0.30). Of these, 29 underwent stress testing and 14 underwent CAG. Only 1 patient had obstructive CAD and underwent percutaneous coronary intervention (PCI). There were 23 patients whose TnI level was abnormal (≥0.30). Of these, 17 underwent stress testing and 13 underwent CAG. Three patients (13%) had obstructive CAD and underwent PCI. The serum TnI level can be used to risk stratify patients who present with episodes of SVT and symptoms of an acute coronary syndrome. Patients with an abnormally high TnI level (>0.3) have a ∼13% risk of obstructive CAD. Those with a normal TnI level had a very low incidence (<5%).