Abstract TP224: Risk Factors for Stroke in Infective Endocarditis

Abstract

Background: Stroke is a common, serious complication of infective endocarditis (IE). We investigated risk factors for IE-associated cerebrovascular disease. Methods: We retrospectively reviewed data of all inpatients with discharge ICD-9 codes of IE admitted to our tertiary care hospital from 1980-2011. The diagnosis of IE was confirmed using the original Duke Criteria. Stroke was confirmed on CT or MRI. Results: Of 1151 hospitalizations (1083 adults), 277 (24%) included IE-related stroke (76% ischemic, 13% hemorrhagic, 10% both). Stroke patients had mean age 56 yrs, 63% male, 93% ’Definite IE’ per Duke Criteria, and 83% Native Valve infection. Organism types were Staph 40%, Strep 30% and Other 30%. Trans-esophageal echo was performed in 53% and MRI in 57%. The Stroke and Non-Stroke Groups showed no significant difference in age, sex, traditional cardiovascular risk factors (Htn, DM, lipids, AFib etc), and type of infectious organism. Patients with Stroke had a significantly higher frequency of multiple vegetations (20% vs 8%, p<0.001), cardiac abscess (16% vs 10%, p<0.01), cardiac surgery (37% vs 26%, p<0.01), sepsis (24% vs 14%, p<0.01) and DIC (9% vs 2%, p<0.01) and a tended to have higher rates of cardiac rupture (19% v 15%, p=0.08) and lower admission platelet counts (224 vs 249 thousand/cmm, p=0.11). The Ischemic Stroke sub-group showed similar high rates for these variables. Multivariate regression analysis showed IE-related stroke to be significantly predicted by the presence of sepsis (O.R. 3.6, 95%CI 1.8-7.0), congestive heart failure (O.R. 2.1, 95%CI 1.3-3.4), prosthetic valve IE (O.R. 2.3, 95%CI 1.13-4.4), and vegetations in aortic (OR 2.4, 95%CI 1.3-4.3) or mitral (OR 6.6, 95%CI 3.5-12.2) valves. Tricuspid vegetations (OR 0.3, 95%CI 0.1-0.7) and higher platelet counts (OR 0.99, 95%CI 0.99-1.0) had a protective effect. Age, Htn, DM, AFib, multiple vegetations, organism type, antibiotic use, and echo findings of cardiac abscess/rupture, did not predict stroke. Stroke patients had significantly worse outcomes with 22% deaths vs. 9% in non-stroke patients (p<0.001). Conclusion: This large 31-year retrospective study shows that potentially treatable conditions such as CHF and sepsis are associated with a higher rate of IE-related stroke.