Prediction of early postoperative cerebral hemorrhage in infective endocarditis patients using magnetic resonance imaging

Impact of Brain MRI on the Diagnosis of Infective Endocarditis and Treatment Decisions: Systematic Review and Meta-Analysis

BACKGROUND. Despite increasing use of brain MRI to evaluate patients with suspected infective endocarditis, the clinical impact of brain MRI in this setting has not yet been systematically reviewed. OBJECTIVE. The purpose of this study was to evaluate the frequency of brain MRI findings in patients with suspected or confirmed infective endocarditis and to determine the impact of such findings on clinical decisions. EVIDENCE ACQUISITION. A systematic search of the PubMed, Embase, and Cochrane databases was performed from January 1, 1990, to December 31, 2020, to identify original research investigations of brain MRI in patients with suspected or confirmed infective endocarditis. Study quality was assessed with QUADAS-2. Study endpoints included the frequency of brain MRI findings and the frequency of diagnostic modifications, modification of therapeutic plan, and modification of valve surgery plan resulting from MRI findings. Frequencies were pooled by means of the inverse variance method. Subgroup analysis was performed. EVIDENCE SYNTHESIS. A total of 21 studies with 2133 patients were included. Overall study quality was considered moderate. In terms of brain MRI findings, the pooled frequency of acute ischemic lesions was 61.9% (95% CI, 50.7-71.9%); of cerebral microbleeds, 52.9% (95% CI, 41.6-63.9%); hemorrhagic lesions, 24.7% (95% CI, 15.1-37.9%); abscess or meningitis, 9.5% (95% CI, 5.6-15.6%); and intracranial mycotic aneurysm, 6.2% (95% CI, 4.0-9.4%). Subgroup analysis after exclusion of three studies in which neurologic findings were the indication for all brain MRI examinations yielded similar frequencies of these findings. Six studies included results on the impact of brain MRI findings on clinical decisions. The frequencies of diagnostic modifications in two studies were 5.4% and 32.1%. The pooled frequency of therapeutic plan modification in six studies was 12.8% (95% CI, 6.5-23.7%) and of surgical plan modification in five studies was 14.2% (95% CI, 8.2-23.4%). CONCLUSION. In patients with suspected or confirmed infective endocarditis, brain MRI examinations commonly show relevant abnormalities that affect diagnostic and therapeutic clinical decisions. CLINICAL IMPACT. The findings support a potential role for screening brain MRI in the evaluation of patients with suspected or confirmed infective endocarditis, regardless of the presence or absence of neurologic symptoms.

Delayed patch repair of a ruptured mitral subvalvular pseudoaneurysm caused by infective endocarditis: a case report

Background

Ruptured subvalvular pseudoaneurysm is a rare but significantly fatal complication of infective endocarditis. We report a successful surgical case of ruptured subvalvular pseudoaneurysm with infective endocarditis.

Case summary

A 46-year-old man presenting with high fever was admitted to a local hospital. Physical examination revealed small erythema and petechiae on his lower limbs. Transthoracic echocardiogram did not show any visible vegetation and valvular disease; however, magnetic resonance imaging (MRI) showed multiple acute cerebral infractions, and methicillin-susceptible Staphylococcus aureus was detected in the blood culture. Infective endocarditis was suspected, and an antibacterial medication was initiated. Twelve days later, he suffered from a sudden cardiogenic shock due to cardiac tamponade. Bloody pericardial effusion (1600 mL) was drained, and his condition improved substantially. Transoesophageal echocardiography after pericardial drainage revealed severe mitral regurgitation and a subvalvular aneurysm at the posteromedial side of the mitral annulus; these were not detected at the time of admission. He was transferred to our hospital for surgery; however, since fresh cerebral bleeding was observed in MRI, the surgery was delayed. Three weeks later, after confirming that the blood culture was negative for any growth, patch repair of the subvalvular pseudoaneurysm and mitral valve repair were performed. Post-operatively, no complication or arrhythmia was observed; he was discharged 25 days later.

Discussion

We report a rare case of successful delayed surgery for a ruptured subvalvular pseudoaneurysm at the posteromedial side of the mitral annulus, which presented complications for infective endocarditis by S. aureus.

Cerebral microbleeds: hearing through the silence-a narrative review

OBJECTIVE

The term cerebral microbleed (CMB) refers to lesions documented as unexpected findings during computed tomography or magnetic resonance imaging examination of the brain. Initially, a CMB was thought to represent hemosiderin-laden macrophages marking an area of a tiny hemorrhage. Recently, histopathologic studies have shown that the structure of a CMB can be variable. To aid in dealing with this finding and judging its clinical significance, this review addresses important aspects of a CMB, including the definition, prevalence, and incidence in various populations, end-organ damage, associated conditions, and whether any action or treatment by the clinician might be indicated.

METHODS

PubMed Medline, EMBASE, BIOSIS, Current Contents, and Derwent Drug Files databases were searched for the keywords "microbleeds-detection-damage", "silent bleeds", "microbleeds", or "silent bleeds AND hemophilia" from 2011-2016. References of retrieved articles were also reviewed and included if applicable.

RESULTS

The published data are found primarily in the imaging literature and focus on diagnostic techniques. Some publications address relationships with diverse, co-existing clinical conditions and implications for treatment, especially in stroke, intracranial hemorrhage, and antithrombotic therapy.

CONCLUSIONS

It is critical for non-radiologist clinicians (primary care, internists, neurologists, hematologists) to be aware of the potential importance of the finding of a CMB, and the fact that these lesions are not always truly silent or without important clinical consequences. As additional studies appear, clinicians may be able to "hear" more clearly through the silence of the CMB and understand potential clinical implications in patients.