Factors related to white blood cell elevation in acute type A aortic dissection.

Aortic dissection may induce a systemic inflammatory reaction. The etiological backgrounds for elevation of the white blood cell count remain to be clarified. In 466 patients with acute type A aortic dissection treated surgically within 48 hours of symptom onset, the etiologic background of an elevated admission white blood cell count and the effect of such elevation on outcomes were assessed retrospectively. Patients' white blood cell count differed significantly in relation to the extent of dissection, with a median (25th, 75th percentile) white blood cell count of 10.4 (8.1, 13.9) x 103/μL for dissection confined to the ascending aorta, 10.5 (8.2,13.) 103/μL for dissection extending to the aortic arch/descending aorta, 11.1 (8.2, 13.7) x 103/μL for extension to the abdominal aorta, and 13.3 (9.8, 15.9) x 103/μL for extension to the iliac artery (p<0.001). With 11.0 x 103/μL used as the cut-off value for white blood cell count elevation, multivariable analysis showed current smoking (p<0.001; odds ratio, 2.79), dissection extending to the iliac artery (p = 0.006; odds ratio, 1.79), age (p = 0.007, odds ratio, 0.98), and no coronary ischemia (p = 0.027, odds ratio, 2.22) to be factors related to the elevated white blood cell count. Mean age differed significantly between patients with and without an elevated white blood cell count (62.3 vs. 68.3 years, p <0.001). Although in-hospital mortality was similar (7.5% vs.10.9%, p = 0.19), 5-year survival was lower in patients without an elevated count (85.7% vs. 78.6%, p = 0.019), reflecting their more advanced age. In conclusion, our data suggest that dissection morphology and patient age influence the acute phase systemic inflammatory response associated with an elevated white blood cell count in patients with ATAAD. A better understanding of this relation may help optimize diagnosis and perioperative care.