Background: Bacterial endocarditis is a rare but important cause of stroke, as treatment strategies and prognosis differ compared with other stroke mechanisms. We sought to determine the incidence of stroke associated with endocarditis and the clinical characteristics and course of affected patients.
Methods: This study was carried out as part of a population-based epidemiologic study of all stroke subtypes conducted every five years in the Greater Cincinnati/Northern Kentucky region. All residents of our five-county region admitted to local hospitals with ischemic or hemorrhagic stroke in 2005 and 2010 were identified via ICD-9 codes 430-436 from hospital and emergency room discharge lists. Patients with an active diagnosis of endocarditis at the time of stroke or a new diagnosis during their acute hospitalization for stroke were identified by study nurse and physician review of clinical data. The incidence of stroke associated with endocarditis was calculated and age-, sex-, and race-adjusted to the 2000 US population.
Results: Presumed bacterial endocarditis was associated with 26 of 5311 strokes (0.5%). The incidence of stroke associated with endocarditis was 1.2 (95% CI 0.7-1.7) cases per 100,000 persons per year. Two strokes were perioperative at the time of valve repair. A majority of cases (24/26) were primary ischemic stroke; symptomatic hemorrhagic conversion occurred in 3 of the 24 ischemic cases. Only 7 of 26 patients had a known diagnosis of endocarditis at the time of stroke. A minority of patients had fever (8/26) or systolic blood pressure <120 (7/26) at first medical encounter, while a majority (15/26) had leukocytosis. Compared with stroke patients without endocarditis, those with endocarditis were younger (58 vs. 72, p < .001), more likely to be black (42% vs. 22%, p = .02), and more likely to die (30-day all-cause case-fatality 31% vs 16%, p =.06). No endocarditis patients were treated with IV tPA.
Conclusions: Endocarditis is an uncommon cause of stroke associated with a high case-fatality. Patients presenting with acute stroke due to endocarditis often lack classic signs of infection such as fever or hypotension.