Abstract 3307: Early Use of Beta-blockers Attenuates Systemic Inflammatory Response and Lung Oxygenation Impairment after Distal Type Acute Aortic Dissection

Abstract

BACKGROUND: Systemic activation of the inflammatory system after aortic injury may play a role in the development of lung oxygenation impairment (LOI) in patients with acute aortic dissection (AAD). We have reported that serum C-reactive protein (CRP) elevation is an independent predictor of this complication. We evaluated the effect of beta-blocker on systemic inflammation and the development of LOI after distal type AAD. METHODS: A total of 49 patients, who were admitted with distal type AAD and treated conservatively, were examined. Patients were divided into 2 groups according to the presence or absence of beta-blocker treatment, started within 24 hours of the onset. White blood cell (WBC) count, serum CRP level and arterial blood gases were measured serially. Clinical outcome, maximum WBC count, maximum CRP level, and lowest PaO 2 /FiO 2 (P/F) ratio were compared between the two groups. RESULTS: There was no difference between the groups in patients’ backgrounds, blood pressure, serum level of CRP, WBC count and P/F ratio on admission. Beta-blocker treatment was associated with lower maximum WBC count (14,856 ± 3201 vs. 11,687 ± 2610 /mm 3 , p =0.0028) and lower maximum serum CRP level (28.2 ± 20.5 vs. 14.2 ± 5.6 mg/dl, p =0.0004). The minimum P/F ratio was higher in patients with beta-blocker than in those without (140 ± 41 vs. 226 ± 90 mmHg, p =0.0076). Multivariate analysis revealed that administration of a beta-blocker was an independent negative determinant of LOI (P/F ratio ≤ 200 mmHg). CONCLUSIONS: Early use of beta-blockers prevented excessive inflammation and LOI after distal type AAD, suggesting a pleiotropic effect of beta-blockers on the inflammatory response after AAD.