Acute ischemic brain lesions in infective endocarditis: incidence, related factors, and postoperative outcome

Multimodality Imaging of Infective Endocarditis

Infective endocarditis (IE) is a complex multisystemic disease resulting from infection of the endocardium, the prosthetic valves, or an implantable cardiac electronic device. The clinical presentation of patients with IE varies, ranging from acute and rapidly progressive symptoms to a more chronic disease onset. Because of its severe morbidity and mortality rates, it is necessary for radiologists to maintain a high degree of suspicion in evaluation of patients for IE. Modified Duke criteria are used to classify cases as "definite IE," "possible IE," or "rejected IE." However, these criteria are limited in characterizing definite IE in clinical practice. The use of advanced imaging techniques such as cardiac CT and nuclear imaging has increased the accuracy of these criteria and has allowed possible IE to be reclassified as definite IE in up to 90% of cases. Cardiac CT may be the best choice when there is high clinical suspicion for IE that has not been confirmed with other imaging techniques, in cases of IE and perivalvular involvement, and for preoperative treatment planning or excluding concomitant coronary artery disease. Nuclear imaging may have a complementary role in prosthetic IE. The main imaging findings in IE are classified according to the site of involvement as valvular (eg, abnormal growths [ie, "vegetations"], leaflet perforations, or pseudoaneurysms), perivalvular (eg, pseudoaneurysms, abscesses, fistulas, or prosthetic dehiscence), or extracardiac embolic phenomena. The differential diagnosis of IE includes evaluation for thrombus, pannus, nonbacterial thrombotic endocarditis, Lambl excrescences, papillary fibroelastoma, and caseous necrosis of the mitral valve. The location of the lesion relative to the surface of the valve, the presence of a stalk, and calcification or enhancement at contrast-enhanced imaging may offer useful clues for their differentiation. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Detection rate of brain MR and MR angiography for neuroimaging abnormality in patients with newly diagnosed left-sided infective endocarditis

We aimed to investigate the detection rate of brain MR and MR angiography for neuroimaging abnormality in newly diagnosed left-sided infective endocarditis patients with/without neurological symptoms. This retrospective study included consecutive patients with definite or possible left-sided infective endocarditis according to the modified Duke criteria who underwent brain MRI and MR angiography between March 2015 and October 2020. The detection rate for neuroimaging abnormality on MRI was defined as the number of patients with positive brain MRI findings divided by the number of patients with left-sided infective endocarditis. Positive imaging findings included acute ischemic lesions, cerebral microbleeds, hemorrhagic lesions, and infectious aneurysms. In addition, aneurysm rupture rate and median period to aneurysm rupture were evaluated on follow-up studies. A total 115 patients (mean age: 55 years ± 19; 65 men) were included. The detection rate for neuroimaging abnormality was 77% (89/115). The detection rate in patients without neurological symptoms was 70% (56/80). Acute ischemic lesions, cerebral microbleeds, and hemorrhagic lesions including superficial siderosis and intracranial hemorrhage were detected on MRI in 56% (64/115), 57% (66/115), and 20% (23/115) of patients, respectively. In particular, infectious aneurysms were detected on MR angiography in 3% of patients (4/115), but MR angiography in 5 patients (4.3%) was insignificant for infectious aneurysm, which were detected using CT angiography (n = 3) and digital subtraction angiography (n = 2) during follow-up. Among the 9 infectious aneurysm patients, aneurysm rupture occurred in 4 (44%), with a median period of aneurysm rupture of 5 days. The detection rate of brain MRI for neuroimaging abnormality in newly diagnosed left-sided infective endocarditis patients was high (77%), even without neurological symptoms (70%).

Role of Cerebral Imaging on Diagnosis and Management in Patients With Suspected Infective Endocarditis

BACKGROUND

Cerebral embolic events (CEEs) are common complications of infective endocarditis (IE), and their presence can modify diagnosis and therapeutic plans. The aim of the present study was to assess the role of cerebral imaging (Cer-Im) on diagnosis and management of patients with suspected IE.

METHODS

This study was conducted at the Lausanne University Hospital, Lausanne, Switzerland, from January 2014 to June 2022. CEEs and IE were defined according to modified Duke criteria of the European Society of Cardiology (ESC) guidelines.

RESULTS

Among 573 patients with IE suspicion and Cer-Im, 239 (42%) patients had neurological symptoms. At least 1 CEE was found in 254 (44%) episodes. Based on Cer-Im findings, episodes were reclassified from rejected to possible or from possible to definite IE in 3 (1%) and 25 (4%) patients, respectively (0% and 2% in asymptomatic patients, respectively). Among the 330 patients with possible or definite IE, at least 1 CEE was found in 187 (57%) episodes. A new surgical indication (in association with left-side vegetation >10 mm) was established in 74/330 (22%) IE patients and 30/155 (19%) asymptomatic IE patients, respectively.

CONCLUSIONS

Cer-Im in asymptomatic patients with IE suspicion showed limited potential for improving the diagnosis of IE. In contrast, performing Cer-Im in asymptomatic patients with IE may be useful for decision making, because Cer-Im findings led to the establishment of new operative indication for valvular surgery in one fifth of patients according to ESC guidelines.

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.

Neurologic complications of infective endocarditis

Infective endocarditis (IE) is an infection primarily affecting the endocardium of heart valves that can embolize systemically and to the brain. Neurologic manifestations include strokes, intracerebral hemorrhages, mycotic aneurysms, meningitis, cerebral abscesses, and infections of the spine. Neurologic involvement is associated with worse mortality, though it does not always portend a poor functional prognosis. Neuroimaging is indicated in patients who have neurologic symptoms, including cerebral vessel imaging in patients who have subarachnoid hemorrhage. In the case of acute ischemic stroke (IS), IV thrombolysis is contraindicated but endovascular thrombectomy may be a consideration. Neurologic findings understandably raise concern about valve surgery when indicated due to the risk of hemorrhage with perioperative anticoagulation. However, most neurologic complications do not preclude valve surgery and valve surgery may in fact be indispensable in some cases to prevent further neurologic problems. Management decisions in patients with IE and neurologic complications should therefore be multidisciplinary with a major contribution from the neurologist.

Valve surgery for infective endocarditis complicated by stroke: surgical timing and perioperative neurological complications

BACKGROUND AND PURPOSE

Ischaemic and hemorrhagic strokes are dreaded complications of infective endocarditis (IE). The timing of valve surgery for IE patients with stroke remains uncertain. The aim was to study perioperative neurological complications in relation to surgical timing.

METHODS

The study cohort consisted of patients diagnosed with acute IE from January 2010 to December 2016. Early surgery was defined as valve surgery within 14 days of IE diagnosis, and late surgery as after 14 days. Neurological complications that occurred within 14 days post-surgery were considered perioperative and classified as new ischaemic stroke or hemorrhagic stroke, expansion of an existing intracranial hemorrhage and new-onset seizures. Perioperative neurological complications were compared by surgical timing and other variables, including pre-surgical imaging.

RESULTS

Overall, 183 patients underwent valve surgery: 92 had early surgery at a median of 8 days (interquartile range 6-11); 91 had late surgery at a median of 28 days (interquartile range 19-50). Twenty patients (10.9%) had 24 complications: 11 ischaemic, six intraparenchymal hemorrhages, three subarachnoid hemorrhages (SAHs) and four new-onset seizures. Rates of neurological complications were similar for early and late surgery groups (10.9% vs. 11%). Enterococcal IE was more common amongst patients with perioperative neurological complications (35% vs. 12.3%, P < 0.01). An acute infarct was present on pre-surgical magnetic resonance imaging of 134 patients (74%) and was not associated with perioperative neurological complications. Thirty-five patients (19.3%) had intracranial hemorrhage on pre-surgical imaging. SAH on pre-surgical imaging was associated with developing SAH perioperatively (66.7% vs. 13.5%, P < 0.01).

CONCLUSION

Early valve surgery for patients with IE complicated by stroke was not associated with perioperative neurological complications.

Neurologic Complications of Infective Endocarditis: A Joint Model for a Septic Thromboembolism and Inflammatory Small Vessel Disease

OBJECTIVES

Embolic events from vegetations are commonly accepted as the main mechanism involved in neurologic complications of infective endocarditis. The pathophysiology may imply other phenomena, including vasculitis. We aimed to define the cerebral lesion spectrum in an infective endocarditis rat model.

DESIGN

Experimental model of Staphylococcus aureus or Enterococcus faecalis infective endocarditis. Neurologic lesions observed in the infective endocarditis model were compared with three other conditions, namely bacteremia, nonbacterial thrombotic endocarditis, and healthy controls.

SETTING

Research laboratory of a university hospital.

SUBJECTS

Male Wistar rats.

INTERVENTIONS

Brain MRI, neuropathology, immunohistochemistry for astrocyte and microglia, and bacterial studies on brain tissue were used to characterize neurologic lesions.

MEASUREMENTS AND MAIN RESULTS

In the infective endocarditis group, MRI revealed at least one cerebral lesion in 12 of 23 rats (52%), including brain infarctions (n = 9/23, 39%) and cerebral microbleeds (n = 8/23, 35%). In the infective endocarditis group, neuropathology revealed brain infarctions (n = 12/23, 52%), microhemorrhages (n = 10/23, 44%), and inflammatory processes (i.e., cell infiltrates including abscesses, vasculitis, meningoencephalitis, and/or ependymitis; n = 11/23, 48%). In the bacteremia group, MRI studies were normal and neuropathology revealed only hemorrhages (n = 2/11, 18%). Neuropathologic patterns observed in the nonbacterial thrombotic endocarditis group were similar to those observed in the infective endocarditis group. Immunochemistry revealed higher microglial activation in the infective endocarditis group (n = 11/23, 48%), when compared with the bacteremia (n = 1/11, 9%; p = 0.03) and nonbacterial thrombotic endocarditis groups (n = 0/7, 0%; p = 0.02).

CONCLUSIONS

This original model of infective endocarditis recapitulates the neurologic lesion spectrum observed in humans and suggests synergistic mechanisms involved, including thromboembolism and cerebral vasculitis, promoted by a systemic bacteremia-mediated inflammation.

High level of D-dimer predicts ischemic stroke in patients with infective endocarditis

Background

Ischemic stroke is one of the most prominent and serious neurological complications of infective endocarditis (IE). Our study was designed to evaluate the predictive value of higher level of plasma D‐dimer on admission for the development of ischemic stroke in patients with IE.

Methods

In this prospective study, a total of 173 consecutive patients with IE were recruited from January 2016 to December 2018. Plasma D‐dimer and other clinical indexes of IE patients were measured after admission. The number of patients who developed ischemic stroke during 6‐month follow‐up was recorded, as well as the occurrence time of ischemic stroke.

Results

Ischemic stroke was observed in 38 (22%) patients during 6‐month follow‐up since definite diagnosis of IE. Patients with ischemic stroke had significantly higher levels of plasma D‐dimer than those of patients without stroke (4982 vs 2205 μg/L, P < .001). In addition, Staphylococcus aureus infection (HR: 1.96, 95% CI: 1.51‐2.42), mitral valve vegetation (HR: 1.52, 95% CI: 1.32‐1.75), and higher levels of on‐admission plasma D‐dimer (HR: 1.35, 95% CI: 1.27‐1.43) were significantly associated with ischemic stroke. Moreover, D‐dimer levels ≥3393 μg/L served as a strong predictor for ischemic stroke in patients with IE, and the sensitivity and specificity were 78% and 83%, respectively.

Conclusion

Our study suggested that higher level of D‐dimer on admission was an independent predictor for ischemic stroke in patients with IE. These patients may require special attention, in particular within the first trimester after IE diagnosis.

Neurological Complications of Infective Endocarditis

PURPOSE OF REVIEW

The purpose of this narrative review and update is to summarize the current knowledge and provide recent advances on the neurologic complications of infective endocarditis.

RECENT FINDINGS

Neurological complications occur in about one-fourth of patients with infective endocarditis. Brain MRI represents a major tool for the identification of asymptomatic lesions, which occur in most of the patients with infective endocarditis. The usefulness of systematic brain imaging and the preferred treatment of patients with infective endocarditis and silent brain lesions remains uncertain. The basis of treatment of infective endocarditis is early antimicrobial therapy. In stroke due to infective endocarditis, anticoagulation and thrombolysis should be avoided. Endovascular treatment can be useful for both acute septic emboli and mycotic aneurysms, but evidence is still limited. In patients with neurological complications, cardiac surgery can be safely performed early, if indicated. The optimal management of a patients with neurological complications of infective endocarditis needs an individualized case discussion and the participation of a multidisciplinary team including neurologists, cardiologists, cardiothoracic surgeons, neuroradiologists, neurosurgeons, and infectious disease specialists.

Pediatric Infective Endocarditis and Stroke: A 13-Year Single-Center Review

OBJECTIVE

We explored the relationship between pediatric infective endocarditis and stroke.

PATIENTS AND METHODS

All children encountered with infective endocarditis from January 2002 to December 2015 were included as our sample, and their medical records were comprehensively reviewed.

RESULTS

Sixty children with infective endocarditis were identified, including 30 boys and 30 girls aged eight months to 18 years (mean ± SD: 10.3 ± 5.6), and om 43 (71.6%) of these individuals had congenital heart disease. Left-sided endocarditis occurred in 25 patients (41.7%), and vegetations were found in 58 individuals (96.6%). The most often encountered microorganisms were Streptococcus viridans and Staphylococcus aureus, which were identified in five and four patients, respectively. Postendocarditis stroke occurred in nine patients, including five with cerebral infarction, two with intracerebral hemorrhage, and one with subarachnoid hemorrhage. The remaining child experienced cerebral infarction, intracerebral hemorrhage and subarachnoid hemorrhage simultaneously. The incidence of stroke in children with left-sided endocarditis was significantly higher than that of which in those who had right-sided endocarditis (32% versus 2.8%, P < 0.01). The most common manifestation of stroke was hemiparesis (55.5%). Two girls died of stroke, and the mortality rate in the patients who had stroke was significantly higher than that in those without stroke (22.2 % versus 3.9 %, P < 0.05).

CONCLUSIONS

Our data indicate that stroke is common among children with infective endocarditis, especially in those with left-sided endocarditis, and major stroke may increase their risk of death. Congenital heart disease is the main underlying disease in children with infective endocarditis in China.

Early Operation in Patients With Mitral Valve Infective Endocarditis and Acute Stroke Is Safe

BACKGROUND

To determine if preoperative embolic stroke is associated with an increased risk of postoperative stroke among patients undergoing early operation for mitral valve (MV) infective endocarditis (IE), we compared outcomes among patients presenting with and without acute stroke.

METHODS

From 2003 to 2015, 243 consecutive patients underwent surgery for active MV IE. Patients were categorized into 2 groups: 72% (174 of 243 patients) with no preoperative acute stroke (clinical, radiographic or both) and 28% (69 of 243 patients) with stroke. Both preoperative and postoperative strokes were confirmed in all patients with brain computed tomography or magnetic resonance imaging and comprehensive examination by a neurologist.

RESULTS

Among patients presenting with stroke, 33% (23 of 69 patients) were asymptomatic and had only positive imaging findings. The median time from admission to operation was 5 days. The overall rate of new postoperative stroke was 4% (10 of 243 patients). The rate of postoperative stroke was not different between the 2 groups: 4% (7 of 174 patients) among patients with no preoperative stroke and 4% (3 of 69 patients) with stroke (p = 0.9). One patient developed a hemorrhagic conversion of an acute infarct. Operative mortality was 7% (13 of 174 patients) among patients with no preoperative stroke and 7% (5 of 69 patients) among patients with stroke (p = 0.9).

CONCLUSIONS

MV surgery for IE and acute stroke can be performed early with a low risk of postoperative neurologic complications. When indicated, surgical intervention for MV IE complicated by acute stroke should not be delayed.

Neurologic Complications of Infective Endocarditis: Recent Findings

PURPOSE OF REVIEW

The purpose of this paper is to provide recent insights in management of neurologic complications of left-sided infective endocarditis (IE).

RECENT FINDINGS

Cerebral lesions observed in IE patients are thought to involve synergistic pathophysiological mechanisms including thromboembolism, sepsis, meningitis, and small-vessel cerebral vasculitis. Brain MRI represents a major tool for the detection of asymptomatic events occurring in the majority of patients. The latter can impact therapeutic decisions and prognosis, especially when cardiac surgery is indicated. In patients presenting with neurologic complications, surgery could be safely performed earlier than previously thought. Symptomatic cerebral ischemic or hemorrhagic events occur in 20-55% of IE patients, whereas asymptomatic events are detected in 60-80% of patients undergoing systematic brain MRI. Management of such patients requires an experienced multidisciplinary team. Recent studies suggest that early cardiac surgery, when indicated, can be performed safely in patients with cerebral ischemic events. Other important issues include the appropriate use of anti-infective and anti-thrombotic agents, and endovascular treatment for mycotic aneurysms. Altered mental status at IE onset, which is associated with brain injury, is a major determinant of short-term outcome.

Utility of Brain Magnetic Resonance Imaging in the Surgical Management of Infective Endocarditis

BACKGROUND

Brain magnetic resonance imaging (MRI) is frequently obtained in patients with infective endocarditis, yet its utility in predicting outcomes for valve replacement surgery in patients is unknown. The objective of this study was to determine how brain MRI findings impact clinical management and outcomes.

METHODS

Demographic and clinical data from electronic medical records at Mayo Clinic were retrospectively reviewed for patients hospitalized with definite or possible infective endocarditis according to the modified Duke criteria between January 1, 2007 and December 31, 2014. There were 364 patients included in the study.

RESULTS

Cardiac valve replacement surgery was performed in 195 of 364 (53.6%) patients, and 95 (48.7%) of the surgical patients underwent preoperative MRI, which was associated with preoperative neurologic symptoms in 56 of 95 (58.9%) patients (odds ratio = 12.92; 95% confidence interval, 5.98-27.93; P <.001). Postoperative neurologic complications occurred in 24 of 195 (12.3%) patients, including new ischemic stroke in 4 of 195 (2.1%) and new intracerebral hemorrhage in 3 of 195 (1.5%). No patients with microhemorrhages developed postoperative hemorrhage. No significant differences existed in rates of postoperative complications between patients with and those without preoperative MRI. There were no substantial associations between preoperative MRI findings and postoperative neurologic complications, functional outcomes as described by the modified Rankin Scale score, or 6-month mortality.

CONCLUSIONS

In patients undergoing valve replacement surgery, preoperative MRI findings were not associated with differences in postoperative outcomes, irrespective of finding or timing of valve replacement surgery.

Reconstructive valve surgery within 10 days of stroke in endocarditis

Background

The optimal timing of surgical treatment for infective endocarditis complicated by cerebrovascular events is controversial, largely due to the perceived risk of perioperative intracranial bleeding. Current guidelines suggest waiting 2 weeks between the diagnosis of stroke and surgery. The aim of this study was to investigate the clinical and neurological outcomes of early surgery following a stroke.

Methods

This was a single-center retrospective analysis of 12 consecutive patients requiring surgery for infective endocarditis between 2011 and 2014 at Rush University Medical Center, with either ischemic ( n = 6) and/or hemorrhagic ( n = 6) cerebrovascular complications. All underwent computed tomographic angiography prior to early valve reconstructive surgery to identify potentially actionable neurological findings. Early valve surgery was performed for ongoing sepsis or persistent emboli. Neurologic risk and outcome were assessed pre- and postoperatively using the National Institutes of Health Stroke Scale and the Glasgow Outcome Scale, respectively.

Results

All 12 patients underwent surgical treatment within 10 days of the diagnosis of stroke. Mortality in the immediate postoperative period was 8%. Eleven of the 12 patients exhibited good neurological recovery in the immediate postoperative period, with a Glasgow Outcome Scale score ≥ 3. There was no correlation between duration of cardiopulmonary bypass and neurological outcomes.

Conclusion

Early cardiac surgery in patients with infective endocarditis and stroke maybe lifesaving with a low neurological risk. Comprehensive neurovascular imaging may help in identifying patient-related risk factors.

Value of brain MRI in infective endocarditis: a narrative literature review

The nervous system is frequently involved in patients with infective endocarditis (IE). A systematic review of the literature was realized in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). This study sought to systematically evaluate the published evidence of the contribution of brain magnetic resonance imaging (MRI) in IE. The aim was to identify studies presenting the incidence and type of MRI brain lesions in IE. Fifteen relevant studies were isolated using the Medline, Embase, and Cochrane databases. Most of them were observational studies with a small number of patients. MRI studies demonstrated a wide variety and high frequency of cerebral lesions, around 80 % of which were mostly clinically occult. This review shows MRI’s superiority compared to brain computed tomography (CT) for the diagnosis of neurologic complications. Recent developments of sensitive MRI sequences can detect microinfarction and cerebral microhemorrhages. However, the clinical significance of these microhemorrhages, also called cerebral microbleeds (CMBs), remains uncertain. Because some MRI neurological lesions are a distinctive IE feature, they can have a broader involvement in diagnosis and therapeutic decisions. Even if cerebral MRI offers new perspectives for better IE management, there is not enough scientific proof to recommend it in current guidelines. The literature remains incomplete regarding the impact of MRI on concerted decision-making. The long-term prognosis of CMBs has not been evaluated to date and requires further studies. Today, brain MRI can be used on a case-by-case basis based on a clinician’s appraisal.

Cerebral imaging in infectious endocarditis: A clinical study

BACKGROUND

Because neurological failure is the most frequent extra-cardiac complication in Infectious Endocarditis (IE), a brain computerised tomography (CT) scan is usually performed. The benefits of magnetic resonance imaging (MRI) have not been clearly established. This study aims to clarify the prevalence and type of cerebral lesions in IE detected using MRI and to compare them with those detected using CT scans.

METHODS

In the Grenoble University Hospital, patients diagnosed with definite or possible endocarditis according to Duke's criteria were screened from 2010-2012. Brain CT and MRI were performed as soon as possible after diagnosis.

RESULTS

Of the 62 patients with IE who underwent at least one cerebral imaging within 3 weeks of diagnosis, Streptococcus (29) and Staphylococcus (14) were the main micro-organisms present. Twenty-eight (45%) patients underwent cardiac surgery. Eight (13%) died before discharge. Twenty (32%) had neurological symptoms. A brain CT-scan was performed on 53 (85%) patients and a MRI was performed on 43 (69%) patients. CT was pathological in 26 (49%) patients, whereas 32 (74%) MRI demonstrated abnormalities. The MRI lesions were classified as follows: ischaemia (48%), microbleeds (34%), haemorrhages (16%), abscesses (9%) and microbial aneurysms (4%). Of the 37 patients who underwent both MRI and CT examinations, ischaemia (48% vs 35%) and microbleeds (34%) demonstrated the difference between the two imaging methods.

CONCLUSION

Through the early diagnosis of cerebral damage, even in asymptomatic cases, MRI may have a role in the IE management, influence any surgical decision and assist in prognosis assessment.

Early Operation for Endocarditis Complicated by Preoperative Cerebral Emboli Is Not Associated With Worsened Outcomes

BACKGROUND

Valve operations for patients presenting with infective endocarditis (IE) complicated by stroke are thought to carry elevated risk of postoperative complications. Our aim was to compare outcomes of IE patients who undergo surgical intervention early after diagnosis of septic cerebral emboli with outcomes of patients without preoperative emboli.

METHODS

All patients undergoing operations for left-sided IE between 1996 and 2013 at our institution were reviewed. Patients undergoing operations more than 14 days after embolic stroke diagnosis (n = 11) and those with purely hemorrhagic lesions (n = 7) were excluded from the analysis. The study included 308 patients who were stratified according to the presence (STR, n = 54) or absence of a preoperative septic cerebral embolus (NoSTR, n = 254). Primary outcomes of interest were the development of a new postoperative stroke and 30-day mortality.

RESULTS

Mean time to surgical intervention from stroke onset was 6.0 ± 4.1 days. Staphylococcus aureus (39% STR vs 21% NoSTR, p = 0.004) infection and annular abscess at operation (52% STR vs 27% NoSTR, p < 0.001) were more prevalent in STR patients. There was no significant difference in 30-day mortality (9.3% STR vs 7.1% NoSTR, p = 0.57) or in the rate of new postoperative stroke (5 [9.4%] STR vs 12 [4.7%] NoSTR, p = 0.19) between groups. In addition, there was no difference in 10-year survival between groups (log-rank p = 0.74).

CONCLUSIONS

Early surgical intervention in patients with IE complicated by preoperative septic cerebral emboli does not lead to significantly worse postoperative outcomes. Early surgical intervention for IE after embolic stroke warrants consideration, particularly in patients with high-risk features such as S aureus or annular abscess, or both.

Clinical significance of cerebrovascular complications in patients with acute infective endocarditis: a retrospective analysis of a 12-year single-center experience

BACKGROUND

Cerebrovascular complications (CVCs) frequently occur in patients with acute infective endocarditis (IE). The aim of this study is to describe the clinical findings of CVCs and to evaluate the impact of CVCs on long-term mortality in patients with IE.

METHODS

We retrospectively analyzed 144 patients who fulfilled the modified Duke's criteria for definite left-sided IE. CVCs were classified into minor (silent cerebral embolism, TIA and stroke with an initial modified Rankin scale ≤ 2) or major (an initial modified Rankin scale ≥ 3) CVCs. Cox proportional hazards model was used for mortality analysis. Hazard ratio (HR) and 95% confidence interval (CI) were obtained.

RESULTS

The mean age of the 144 patients (96 males and 48 females) was 49.1 years (range 6-85 years). A CVC was found in 37 (25.7%) patients. Of these, 25 were treated with surgical therapy. The patients who underwent early surgery within 2 weeks after stroke had a statistical trend toward a higher risk of postoperative brain hemorrhage (50% versus 4.8%, P = 0.057 by Fisher exact test). The minor CVC group had a similar risk of death as the no-CVC group (P = 0.803; HR 0.856; CI 0.253-2.894), whereas the major CVC group had a higher mortality (P = 0.013; HR 2.865; CI 1.254-6.548) than the no-CVC group. In the multivariate analysis, major CVC (P = 0.002; HR 3.893; CI 1.649-9.194) was a significant predictor of mortality in IE patients, together with advanced age (P = 0.005; HR 3.138; CI 1.421-6.930) and prosthetic valve IE (P = 0.008; HR 2.819; CI 1.315-6.044).

CONCLUSIONS

IE can give rise to various forms of CVC, most frequently, acute ischemic brain lesions. In our study, major CVC was associated with high risk of mortality although total CVC was not significantly related to the risk of death in patients with IE.

Neurological complications of infective endocarditis: new breakthroughs in diagnosis and management

Neurological complications are frequent in infective endocarditis (IE) and increase morbidity and mortality rates. A wide spectrum of neurological disorders may be observed, including stroke or transient ischemic attack, cerebral hemorrhage, mycotic aneurysm, meningitis, cerebral abscess, or encephalopathy. Most complications occur early during the course of IE and are a hallmark of left-sided abnormalities of native or prosthetic valves. Ischemic lesions account for 40% to 50% of IE central nervous system complications. Systematic brain MRI may reveal cerebral abnormalities in up to 80% of patients, including cerebral embolism in 50%, mostly asymptomatic. Neurological complications affect both medical and surgical treatment and should be managed by an experimented multidisciplinary team including cardiologists, neurologists, intensive care specialists, and cardiac surgeons. Oral anticoagulant therapy given to patients presenting with cerebral ischemic lesions should be replaced by unfractionated heparin for at least 2 weeks, with a close monitoring of coagulation tests. Recently published data suggest that after an ischemic stroke, surgery indicated for heart failure, uncontrolled infection, abscess, or persisting high emboli risk should not be delayed, provided that the patient is not comatose or has no severe deficit. Surgery should be postponed for 2 to 3 weeks for patients with intracranial hemorrhage. Endovascular treatment is recommended for cerebral mycotic aneurysms, if there is no severe mass effect. Recent data suggests that neurological failure, which is associated with the location and extension of brain injury, is a major determinant for short-term prognosis.