Prognostic value of cardiac troponin in dialysis patients with paroxysmal supraventricular tachycardia

Abstract

A rise in cardiac troponin I (cTnI) is common in supraventricular tachycardia (SVT). While troponin elevation in SVT is thought to be a predictor of future adverse events in patients with prior coronary artery disease, the prognostic significance of cTnI in endstage kidney disease (ESKD) patients with SVT are not known. We aimed to examine the prognostic significance of cTnI in ESKD patients presenting with SVT in the emergency department. This was a retrospective, multiple-center observational study utilizing regularly collected electronic medical records. We screened electronic medical records of all dialysis patients presenting to the emergency departments in 5 hospitals over 12 years with SVT. These patients were divided into whether cTnI was tested, and were further stratified into the cTnI-positive and cTnI-negative groups. The primary outcome of the study was the 3-year risk of major adverse cardiovascular events (MACE). Sixty-two patients were qualified for inclusion. Fifty-seven patients (91.9%) were tested for cTnI, and 5 patients were not. Patients with the cTnI test were older (P = .03) and had a longer length of hospital stay (P < .001). Forty-seven patients (82.5%) had a positive result, and 10 (17.5%) had a negative result. A history of hypertension (P = .013) and decreased left ventricular ejection fraction (P = .048) were the independent predictors of cTnI elevation. After a mean follow-up period of 20.6 ± 14.7 months, there were no differences in 3-year MACE between patients with or without elevated cTnI levels in Kaplan-Meier analysis (P = .34). A history of coronary artery disease was the only independent predictor of 3-year MACE (P = .017). Through the subgroup analysis, a history of coronary artery disease (HR 2.73; CI 1.01-7.41; P = .049) remained an independent risk factor for 3-year MACE in patients with elevated cTnI levels. A large proportion (82.5%) of troponin elevation was observed in ESKD patients with SVT, but it had a poor correlation with MACE.