Infective endocarditis and neurologic events: indications and timing for surgical interventions

Contemporary surgical management of infective endocarditis of the aortic root

Infective endocarditis involving the aortic root is associated with a high degree of morbidity and mortality. Native aortic root infections can develop from aggressive organisms or from delays in diagnosis or definitive care, whereas prosthetic valve infections commonly result in extensive destruction of the aortic root and neighboring structures. Early detection, tailored antibiotic therapy, thoughtful pre-operative planning, and multidisciplinary heart team management are the keys to optimizing patient outcomes. Aggressive and complete surgical debridement are mandatory prior to aortic root reconstruction. Surgical experience and patient-centered decision making are critical in selecting the optimal reconstructive strategy for the aortic root and adjacent structures.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-023-01604-6.

Clinical Features and Patient Outcomes in Infective Endocarditis with Surgical Indication: A Single-Centre Experience

BACKGROUND

Infective endocarditis (IE) is marked by a heightened risk of embolic events (EEs), uncontrolled infection, or heart failure (HF).

METHODS

Patients with IE and surgical indication were enrolled from October 2015 to December 2018. The primary endpoint consisted of a composite of major adverse events (MAEs) including all-cause death, hospitalizations, and IE relapses. The secondary endpoint was all-cause death.

RESULTS

A total of 102 patients (66 ± 14 years) were enrolled: 50% with IE on prosthesis, 33% with IE-associated heart failure (IE-aHF), and 38.2% with EEs. IE-aHF and EEs were independently associated with MAEs (HR 1.9, 95% CI 1.1-3.4, p = 0.03 and HR 2.1, 95% CI 1.2-3.6, p = 0.01, respectively) and Kaplan-Meier survival curves confirmed a strong difference in MAE-free survival of patients with EEs and IE-aHF (p < 0.01 for both). IE-aHF (HR 4.3, 95% CI 1.4-13, p < 0.01), CRP at admission (HR 5.6, 95% CI 1.4-22.2, p = 0.01), LVEF (HR 0.9, 95% CI 0.9-1, p < 0.05), abscess (HR 3.5, 95% CI 1.2-10.6, p < 0.05), and prosthetic detachment (HR 4.6, 95% CI 1.5-14.1, p < 0.01) were independently associated with the all-cause death endpoint.

CONCLUSIONS

IE-aHF and EEs were independently associated with MAEs. IE-aHF was also independently associated with the secondary endpoint.

Antithrombotic Therapy in Patients With Infective Endocarditis: A Systematic Review and Meta-Analysis

Background

Antithrombotic therapy (ATT) in patients with infective endocarditis (IE) is challenging.

Objectives

The authors evaluated the impact of anticoagulant and antiplatelet therapy on clinical endpoints in IE patients.

Methods

We performed a systematic review and meta-analysis comparing IE patients with prior and/or ongoing use of ATT vs those without any ATT during IE course. Primary outcome was reported in-hospital cerebrovascular events. Secondary outcomes were in-hospital mortality, intracranial hemorrhage (ICH), systemic thromboembolism (ST), and mortality within 6 months.

Results

Twelve studies, with a total of 12,151 patients, were included. The primary endpoint was not different comparing 10,115 IE patients with or without prior anticoagulation (OR: 1.10; 95% CI: 0.56-2.17; P = 0.77) or comparing 838 IE patients with or without prior antiplatelet (OR: 0.90; 95% CI: 0.61-1.33; P = 0.61). In-hospital mortality was lower in IE patients with prior anticoagulation compared to those without (OR: 0.74; 95% CI: 0.57-0.96; P = 0.03). There was no difference in reported ICH rates between patients with or without prior anticoagulation (OR: 0.54; 95% CI: 0.27-1.09; P = 0.09) or between patients with or without prior antiplatelet (OR: 0.35; 95% CI: 0.11-1.10; P = 0.07). The rate of ST was lower in IE patients with prior antiplatelet therapy compared to those without (OR: 0.53; 95% CI: 0.38-0.72; P < 0.01).

Conclusions

ATT in IE patients was not associated with higher frequency of cerebrovascular events or ICH. Moreover, we found that the use of anticoagulation was associated with decreased in-hospital mortality and the use of antiplatelets was associated with decreased ST. Due to the limitations of this study, these results should be interpreted cautiously showing the necessity of a randomized setup.

An enigmatic presentation of Escherichia coli endocarditis: Emphasizing the role of brain magnetic resonance imaging

Key Clinical Message

Infective endocarditis should be considered in any febrile individual with acute onset neurological symptoms. If suspicion is high, a negative brain computed tomography does not virtually exclude embolism, and magnetic resonance imaging is warranted.

Abstract

A diagnosis of infective endocarditis (IE) is often delayed, particularly in those infected with unusual organisms. Hereby, we report a case of a female patient presented with dysarthria, confusion, and altered mental status after being treated for Escherichia coli bacteremia. Computed tomography of the brain was unrevealing; however, scattered embolic phenomena were visualized on magnetic resonance imaging (MRI). The case underscores the importance of clinical awareness, particularly in the setting of unusual microorganisms, and the role of brain MRI in the diagnosis of IE.

Complicated Native Aortic Valve Endocarditis: Complexities of Medical Optimisation Prior to Surgical Repair for Large Vegetations With Systemic Emboli

A 43-year-old male with no history of valvular disease but ongoing intravenous drug use presented with acute confusion, pyrexia, and Osler's nodes. Transthoracic echocardiography uncovered a large 17 x 15 mm-sized vegetation on the aortic valve, causing moderate-to-severe aortic regurgitation. Subsequent multi-organ compromise and complexities regarding treatment adherence delayed surgical intervention; thus, six weeks of antibiotic therapy and medical optimisation, in close collaboration with cardiology, microbiology, and cardiothoracic teams, enabled definitive aortic valve repair to be performed. This case highlights the challenges encountered when managing this life-threatening condition and the obstacles of enacting the guidelines recommendations regarding the timing of surgical intervention. Our case portrays the effectiveness of medical management as bridge-to-surgery in patients not in a position to undergo immediate surgical repair.

Surgical Atrial Septal Patch Endocarditis in a Patient with a Complete Corrected Atrioventricular Canal Defect: A Case Report and Review of the Literature

Infective endocarditis (IE) is common in patients with corrected congenital heart disease (CHD) with a residual lesion, but is rarely found on surgical patches used to close atrial septal defects (ASDs). This is also reflected in the current guidelines that do not recommend antibiotic therapy for patients with a repaired ASD with no residual shunt six months after closure (percutaneous or surgical). However, the situation could be different in the case of mitral valve endocarditis, which causes leaflet disruption with severe mitral insufficiency and could seed the surgical patch. We present herein a 40-year-old male patient with a past medical history of a complete surgically corrected atrioventricular canal defect performed in childhood who presented with fever, dyspnea and severe abdominal pain. Transthoracic and transesophageal echocardiography (TTE and TEE) revealed vegetation at the level of the mitral valve and the interatrial septum. The CT scan confirmed ASD patch endocarditis and multiple septic emboli, guiding the therapeutic management. An accurate evaluation of cardiac structures should be mandatory when a systemic infection is detected in CHD patients, even if the defects were surgically corrected, because the detection and eradication of such infectious foci as well as a surgical reintervention are particularly difficult to achieve in this subpopulation.

Endovascular Treatment of Large Vessel Occlusion Strokes Caused by Infective Endocarditis: A Systematic Review, Meta-Analysis, and Case Presentation

Thromboembolic events such as acute ischemic strokes are frequently seen in patients with infective endocarditis (IE). It is generally recommended that the administration of intravenous thrombolytics is avoided in these patients as they might encounter a higher risk of intracranial hemorrhages. In this setting, particularly with a large vessel occlusion (LVO), a mechanical thrombectomy may be an alternative option. In this systematic review and meta-analysis, we aimed to investigate the outcomes and safety of mechanical thrombectomies for LVO stroke patients secondary to IE. A search strategy was developed and we searched PubMed, Scopus, Web of Sciences, and Embase using the words "infective endocarditis", "stroke", and "mechanical thrombectomy". Including 6 studies and 120 patients overall, this study showed that a mechanical thrombectomy might reduce the National Institute of Health Stroke Scale (NIHSS), with a weighted mean difference of -3.06 and a 95% CI of -4.43 to -1.70. The pooled rate of symptomatic intracranial hemorrhages and all-cause mortality were also determined to be 15% (95% CI: 4-47%) and 34% (95% CI:14-61%), respectively. The results of this study showed that a mechanical thrombectomy might be an effective and reasonably safe option for the treatment of LVO strokes caused by IE. However, more large-scale studies are needed to consolidate these results.

Screening neuroimaging in neurologically asymptomatic patients with infective endocarditis

BACKGROUND AND PURPOSE

Neurological complications from infective endocarditis (IE) are common and often present with minimal clinical symptoms. In this study, we examine whether screening neuroimaging in asymptomatic patients results in increased detection of neurological complications and leads to improved patient outcomes.

METHODS

Using a database of consecutive adults with IE admitted to a single health system from 2015 to 2019, we selected patients who presented without any neurological symptoms and determined whether these patients underwent screening neuroimaging. The presence of septic emboli, territorial infarcts, intracranial hemorrhage, and mycotic aneurysms was recorded. Variables with significant differences in univariable analyses (p < .1) between those with and without screening neuroimaging were entered into regression models with age and sex to determine predictors of neurological complications and favorable discharge outcomes (modified Rankin score ≤2).

RESULTS

A total of 214 patients were included in the study, of which 154 (72%) received screening neuroimaging. Septic emboli were more common in patients who underwent screening imaging (31% vs. 15%, p = 0.02). In the first multivariate analysis, screening neuroimaging was associated with septic emboli (adjusted odds ratio [aOR] = 2.44, 95% confidence interval [CI]: [1.03-5.75], p = 0.04). In the second multivariate analysis, territorial infarcts (aOR = 0.28, 95% CI: [0.11-0.73], p = .01), but not septic emboli (aOR = 0.71, 95% CI: [0.36-1.43], p = 0.34), were associated with a favorable discharge outcome.

CONCLUSIONS

Screening neuroimaging leads to the detection of more septic emboli in IE, but only territorial infarcts (in contrast to septic emboli) correlate with an unfavorable discharge outcome.

Heart-Brain Relationship in Stroke

The patient presenting with stroke often has cardiac-related risk factors which may be involved in the mechanism of the stroke. The diagnostic assessment is predicated on recognition of this potential relationship. Naturally, an accurate history is of utmost importance in discerning a possible cause and effect relationship. The EKG is obviously an important clue as well as it allows immediate assessment for possible cardiac arrhythmia, such as atrial fibrillation, for possible acute ischemic changes reflective of myocardial ischemia, or there may be indirect factors such as the presence of left ventricular hypertrophy, typically seen with longstanding hypertension, which could be indicative of a hypertensive mechanism for a patient presenting with intracerebral hemorrhage. For all presentations in the emergency room, the vital signs are important. An elevated body temperature in a patient presenting with acute stroke raises concern about possible infective endocarditis. An irregular-irregular pulse is an indicator of atrial fibrillation. A markedly elevated blood pressure is not uncommon in both the acute ischemic and acute hemorrhagic stroke setting. One tends to focus on possible cardioembolic stroke if there is the sudden onset of maximum neurological deficit versus the stepwise progression more characteristic of thrombotic stroke. Because of the more sudden loss of vascular supply with embolic occlusion, seizure or syncope at onset tends to be supportive of this mechanism. Different vascular territory involvement on neuroimaging is also a potential indicator of cardioembolic stroke. Identification of a cardiogenic source of embolus in such a setting certainly elevates this mechanism in the differential. There have been major advances in management of acute cerebrovascular disease in recent decades, such as thrombolytic therapy and endovascular thrombectomy, which have somewhat paralleled the advances made in cardiovascular disease. Unfortunately, the successful limitation of myocardial damage in acute coronary syndrome, with intervention, does not necessarily mirror a similar salutary effect on functional outcome with cerebral infarction. The heart can also affect the brain from a cerebral perfusion standpoint. Transient arrhythmias can result in syncope, while cardiac arrest can result in hypoxic-ischemic encephalopathy. Cardiogenic dementia has been identified as a mechanism of cognitive impairment associated with severe cardiac failure. Structural cardiac abnormalities can also play a role in brain insult, and this can include tumors, such as atrial myxoma, patent foramen ovale, with the potential for paradoxical cerebral embolism, and cardiomyopathies, such as Takotsubo, can be associated with precipitous cardioembolic events.

In-hospital Outcomes of Infective Endocarditis from 1978 to 2015: Analysis Through Machine-Learning Techniques

Background

Early identification of patients with infective endocarditis (IE) at higher risk for in-hospital mortality is essential to guide management and improve prognosis.

Methods

A retrospective analysis was conducted of a cohort of patients followed up from 1978 to 2015, classified according to the modified Duke criteria. Clinical parameters, echocardiographic data, and blood cultures were assessed. Techniques of machine learning, such as the classification tree, were used to explain the association between clinical characteristics and in-hospital mortality. Additionally, the log-linear model and graphical random forests (GRaFo) representation were used to assess the degree of dependence among in-hospital outcomes of IE.

Results

This study analyzed 653 patients: 449 (69.0%) with definite IE; 204 (31.0%) with possible IE; mean age, 41.3 ± 19.2 years; 420 (64%) men. Mode of IE acquisition: community-acquired (67.6%), nosocomial (17.0%), undetermined (15.4%). Complications occurred in 547 patients (83.7%), the most frequent being heart failure (47.0%), neurologic complications (30.7%), and dialysis-dependent renal failure (6.5%). In-hospital mortality was 36.0%. The classification tree analysis identified subgroups with higher in-hospital mortality: patients with community-acquired IE and peripheral stigmata on admission; and patients with nosocomial IE. The log-linear model showed that surgical treatment was related to higher in-hospital mortality in patients with neurologic complications.

Conclusions

The use of a machine-learning model allowed identification of subgroups of patients at higher risk for in-hospital mortality. Peripheral stigmata, nosocomial IE, absence of vegetation, and surgery in the presence of neurologic complications are predictors of fatal outcomes in machine learning–based analysis.