Troponin Elevation in Sickle Cell Disease

Abstract

Objective: Sickle cell disease is associated with cardiovascular abnormalities. Troponin is not typically measured in this population, and thus the significance of abnormal levels of troponin is unknown. We wanted to evaluate the use of troponin and factors that predispose troponin elevation in patients admitted with sickle cell pain crisis (SCPC). Methods: We reviewed data of consecutive patients admitted to a tertiary care hospital between 2006 and 2011 with a diagnosis of SCPC. Subjects with elevated troponin (ET) (troponin I >0.04 ng/mL) were compared with those with normal troponin (NT) for demographics, risk factors, presence of echocardiography-derived tricuspid regurgitant jet velocity (TRV) ≥3 m/s suggesting pulmonary hypertension, and laboratory tests. The Mann-Whitney U test was used to compare groups. Results: Two hundred eighty-three of 724 patients admitted with SCPC had chest pain. Troponin I was measured in 63 patients: 51 had NT and 12 had ET ranging from 0.06 to 3.42 ng/ml. ET was associated lower hemoglobin (p = 0.02), lower hematocrit (p = 0.02), lower platelet number (p < 0.001), higher LDH (p = 0.012), higher AST levels (p = 0.004), higher bilirubin levels (p = 0.006), and TRV ≥3 m/s (p = 0.028). Conclusions: Troponin was measured in <10% of patients with SCPC, and 1 out of 5 of them had ET. Troponin elevation was not associated with traditional cardiovascular risk factors but was associated with lower hematocrit, elevated LDH, bilirubin levels, and TRV ≥3 m/s.