The extension of infection in native valve infective endocarditis (IE) from valvular structures to the periannular tissue is incompletely understood. It is unknown, for example, whether the prognosis of patients with aortocavitary fistulae is worse than that of those with nonruptured abscesses. The aims of this study were to determine the distinct clinical characteristics of patients with aortocavitary fistulae and nonruptured abscesses in native valve IE and to evaluate the impact of fistulization on the outcomes of patients with native aortic valve IE complicated with periannular lesions. In a retrospective multicenter study of 2,055 native valve IE episodes, 201 patients (9.8%) with periannular complications in aortic valve IE were identified (46 with aortocavitary fistulization and 155 with nonruptured abscesses). Rates of heart failure (p = 0.07), ventricular septal defect (p <0.001), and third-degree atrioventricular block (p = 0.07) were higher in patients with fistulization. Surgical treatment was undertaken in 172 patients (86%), and in-hospital mortality in the overall population was 29%. Multivariate analysis identified age >60 years (odds ratio [OR] 2.6, 95% confidence interval [CI] 1.3 to 5.2), renal failure (OR 3.0, 95% CI 1.5 to 6.0), and moderate or severe heart failure (OR 2.5, 95% CI 1.2 to 5.2) as independent risk factors for death. There was a trend toward increased in-hospital mortality in patients with aortocavitary fistulae (OR 1.5, 95% CI 0.7 to 3.0). The actuarial 5-year survival rate in surgical survivors was 80% in patients with fistulae and 92% in patients with nonruptured abscesses (log-rank p = 0.6). In conclusion, aortocavitary fistulous tract formation in the setting of native valve IE is associated with higher rates of heart failure, ventricular septal defect, and atrioventricular block than nonruptured abscess. Despite these higher rates of complications, fistulous tract formation in the current era of IE is not an independent risk factor for mortality.