Incidence and prognosis of embolic events and metastatic infections in infective endocarditis

Abstract

Aims: In infective endocarditis, the true incidence of embolic events and metastatic infections remains unknown probably because a large number of events are asymptomatic. The consequences of the prognosis of such events have never been evaluated by a prospective follow-up. This study aimed to assess the incidence of symptomatic or asymptomatic embolic events and metastatic infections in definite infective endocarditis and to determine whether these events carry a risk of mortality.

Methods and results: From January 1991 to December 1993, 102 patients with suspected or known infective endocarditis were referred to our institution. Among them, we selected 68 patients (50 males, 18 females, mean age = 52.7 years) exhibiting definite infective endocarditis according to the Duke University criteria. Blood cultures were positive in 49 cases (72%). Echocardiography revealed valvular vegetations in 55 cases (81%). Irrespective of the clinical presentation, patients were examined radiologically by cerebral computed tomography scanning (n = 60), magnetic resonance imaging (n = 3), abdominal computed tomography scanning (n = 32) or abdominal echocardiography (n = 20). Depending on the symptoms, thoracic computed tomography scanning (n = 22), pulmonary angiography (n = 2), ventilation-perfusion scintigraphy (n = 4), or gallium citrate radionuclide scanning (n = 7) were also performed. All patients were prospectively followed-up for a mean period of 21.4 +/- 17.5 months. In 35 patients (51%), 51 embolic or metastatic events were revealed, involving the central nervous system (n = 23), spleen (n = 7), kidney (n = 5), lung (n = 5), liver (n = 4), bone and joint (n = 4), iliac (n = 2) or mesenteric (n = 1) arteries. During the hospital stay, the mortality rate was higher in patients exhibiting embolic or metastatic events (20 vs 12%), but the difference did not reach statistical significance. Kaplan-Meier analysis demonstrated no difference in long-term follow-up.

Conclusion: Our data suggest that embolic or metastatic events had a high incidence (51%) during infective endocarditis, but were not associated with significant attributable mortality.