Thrombocytopenia: an early marker of late mortality in type B aortic dissection

Mid-term and long-term mortality after aortic dissection remain high and due to unknown factors. To determine predicting factors at the acute phase associated with mid- and long-term all-cause mortality, patients with type B aortic dissection including intramural hematoma, treated in one referral university center in an area with a population of 4 million, were analyzed over a period of 12 years (from 1996 to 2008). Based on the total population, 77 patients discharged after type B aortic dissection (including 11 intramural hematoma) were recorded as treated with either medical treatment alone (n = 41) or with additional endovascular therapy (n = 36). The mean follow-up period was 50.8 months, with a survival rate of 78 % (17 deaths). Patient history, symptoms, medical treatment, biological parameters, imaging, and intervention during acute phase (more than 150 parameters) were analyzed to identify any relationship with complications and death. Kaplan-Meier survival curve and Cox proportional hazards analyses identified independent predictors of follow-up mortality from any cause. Factors influencing mortality (P < 0.05) were a low systolic blood pressure (SBP) at admission, a thrombocytopenia in the acute period, chronic bronchitis, diameter of ascending aorta, and renin-angiotensin system inhibitor intake. Independent predictors of mortality were chronic bronchitis (P = 0.0022, hazard ratio (HR) 17.5), early thrombocytopenia (P = 0.042, HR 3.5), and admission SBP <120 mmHg (P = 0.0048, HR 7.928). Treated (medical ± endovascular) type B aortic dissection held a worse long-term prognosis, which can be correlated with predicting factors, especially in-hospital thrombocytopenia, and should require closer follow-up.