Elevated Serum Leukocytes are Predictive of Cardiac Injury Following Aneurysmal Subarachnoid Hemorrhage

Objectives: Aneurysmal subarachnoid hemorrhage (aSAH) accounts for 5% of strokes but results in significant morbidity and mortality. In addition to systemic inflammation, up to half of patients develop cardiac injury; however, the relationship between systemic inflammation and cardiac injury after aSAH is unknown. We investigated changes in leukocyte counts in relation to cardiac dysfunction Materials and methods: We reviewed the records of consecutive patients with SAH at our large academic medical referral center. The inclusion criteria were aSAH and available cardiac troponin I (cTnI) levels within 48 h of admission. The primary outcome was cardiac injury, defined as cTnI ≥0.04 ng/mL (lab reference range 0.01–0.03 ng/mL). We compared baseline characteristics, including serum leukocyte counts and performed univariable and multivariable logistic regression analysis to determine whether changes in leukocyte subpopulations predict cardiac injury. Results: Of 288 SAH patients, 250 met inclusion criteria. Of these, 116 (46.4%) had elevated cTnI. In univariable analysis, total leukocyte count (p < 0.001), absolute neutrophil count (ANC, p < 0.001), and absolute monocyte count (p = 0.013), were associated with elevated cTnI. in multivariable analysis, total leukocyte count (OR=1.079, p = 0.037) and ANC (OR=1.081, p = 0.044) remained predictors of elevated cTnI. Adjusted ANC distinguishes between aSAH patients with normal and elevated TnI (area under the curve=0.766, p < 0.001) with specificity of 89.2%. Conclusions: Elevated total leukocytes and ANC are independently associated with cardiac injury in aSAH. Systemic inflammatory responses after aSAH may play a role in cardiac dysfunction, warranting additional studies to further characterize how cardiac inflammation after aSAH drives subsequent morbidity and mortality.