Clinical utility of cerebral angiography in the preoperative assessment of endocarditis

Abstract

Cerebral angiography is an invasive procedure utilized without supporting guidelines in preoperative evaluations of infective endocarditis (IE). It is used to identify mycotic intracranial aneurysm, which is suspected to increase the risk of intracranial bleeding during cardiac surgery. Our objectives were to: (1) assess the utility of cerebral angiography by determining which subset of IE patients benefit from its performance; and (2) identify clinical and noninvasive screening tests that can preclude the need for invasive cerebral angiography. Retrospective analysis was performed of all patients treated surgically for IE from 7/2007 to 1/2012 and discharged with medical treatment for IE from 7/2007 to 7/2009 presenting to a large academic center. Of the 151 patients who underwent cerebral angiography, mycotic aneurysm was identified in seven (prevalence=4.6%; 95% CI 2.3-9.3%). Five had viridans group streptococci as the causative IE microorganism (p=0.0017). Noninvasive imaging and particularly absence of intracranial bleed on magnetic resonance imaging conveys a negative predictive value (NPV) of 0.977 (95% CI 0.879-0.996). Absence of a focal neurologic deficit or altered mental status convey a NPV of 0.990 (95% CI 0.945-0.998) and 0.944 (95% CI 0.883-0.974), respectively. Clinical suspicion for mycotic aneurysm and thus utilization of cerebral angiography is likely necessary only in the setting of acute neurologic deficits and when noninvasive imaging demonstrates acute intracranial bleed. A novel association between viridans group streptococci and intracranial mycotic aneurysm is demonstrated.

Magnetic Resonance Imaging Susceptibility-Weighted Imaging Lesion and Contrast Enhancement May Represent Infectious Intracranial Aneurysm in Infective Endocarditis

“…A prior study of IIA with DSA found that the absence of focal neurological deficit or encephalopathy conveyed high NPV and the absence of acute intracranial hemorrhage also had a high NPV for the presence of IIA [16]. However, in our cohort, the NPVs, sensitivity, and specificity were lower for those variables.…”

“…The frequency of IIAs who underwent DSA (17.6%) in our cohort is higher than previously reported (5-9%) [6,16]; this is likely due to selection bias because our cohort consists of patients with acute/subacute focal neurological presentation or abnormal cerebral imaging. Therefore, true prevalence of IIA among persons with IE is likely far lower than that indicated in our report.…”

Surgical management of infective endocarditis complicated by ischemic stroke

“…Patients with documented ischemic stroke, asymptomatic cerebral septic emboli, or neurological findings suggestive of stroke should undergo additional imaging, if possible, including MRI with and without gadolinium, for further diagnosis and risk stratification Cerebral angiography should be reserved for patients with evidence of hemorrhage on noninvasive imaging, focal neurologic deficits, or altered mental status Surgery for IE is associated with higher risk of neurological complications than valve surgery in non‐IE patients including hemorrhagic transformation of ischemic strokes and new ischemic or hemorrhagic lesions …”

“…CT and MRI are thought to be poorly sensitive in identifying mycotic aneurysms and for that reason cerebral angiography has been employed. An analysis of 151 patients with IE undergoing cerebral angiography demonstrated that noninvasive imaging, particularly the absence of intracranial bleed on MRI, conveyed a negative predictive value (NPV) of 0.977 (95% confidence interval [CI] 0.879‐0.996) for the presence of mycotic aneurysm . Absence of focal neurologic deficit or altered mental status were found to convey a NPV of 0.990 (95% CI 0.945‐0.998) and 0.944 (95% CI 0.883‐0.974), respectively.…”

Dynamic Angiographic Nature of Cerebral Mycotic Aneurysms in Patients With Infective Endocarditis

“…In patients who presented with hemorrhage, 14 of 63 (22.2%) harbored an MA. In a similar study, Monteleone et al 6 identified MA in 7 of 151 (4.6%) patients who underwent cerebral angiography. Only one MA >3 mm was identified by noninvasive imaging (sensitivity, 0.17).…”