Comparison of Clinical Characteristics and Prognosis in Patients with Right- and Left-sided Infective Endocarditis

Embolic Events in Infective Endocarditis: A Comprehensive Review

Infective endocarditis (IE) is a life-threating entity with three main complications: heart failure (HF), uncontrolled infection (UI) and embolic events (EEs). HF and UI are the main indications of cardiac surgery and have been studied thoroughly. On the other hand, much more uncertainty surrounds EEs, which have an abrupt and somewhat unpredictable behaviour. EEs in the setting of IE have unique characteristics that must be explored, such as the potential of hemorrhagic transformation of stroke. Accurately predicting which patients will suffer EEs seems to be pivotal to achieve an optimal management of the disease, but this complex process is still not completely understood. The indication of cardiac surgery in order to prevent EEs in the absence of HF or UI is in question as scientific evidence is controversial and mainly of a retrospective nature. This revision addresses these topics and try to summarize the evidence and recommendations about them.

Percutaneous mechanical aspiration in patients with right-sided infective endocarditis: An analysis of the national inpatient sample database-2016-2020

BACKGROUND

Given the challenges of conventional therapies in managing right-sided infective endocarditis (RSIE), percutaneous mechanical aspiration (PMA) of vegetations has emerged as a novel treatment option. Data on trends, characteristics, and outcomes of PMA, however, have largely been limited to case reports and case series.

AIMS

The aim of the current investigation was to provide a descriptive analysis of PMA in the United States and to profile the frequency of PMA with a temporal analysis and the patient cohort.

METHODS

The International Classification of Diseases, 10th Revision codes were used to identify patients with RSIE in the national (nationwide) inpatient sample (NIS) database between 2016 and 2020. The clinical characteristics and temporal trends of RSIE hospitalizations in patients who underwent PMA was profiled.

RESULTS

An estimated 117,955 RSIE-related hospital admissions in the United States over the 5-year study period were estimated and 1675 of them included PMA. Remarkably, the rate of PMA for RSIE increased 4.7-fold from 2016 (0.56%) to 2020 (2.62%). Patients identified with RSIE who had undergone PMA were young (medial age 36.5 years) and had few comorbid conditions (median Charlson Comorbidity Index, 0.6). Of note, 36.1% of patients had a history of hepatitis C infection, while only 9.9% of patients had a cardiovascular implantable electronic device. Staphylococcus aureus was the predominant (61.8%) pathogen. Concomitant transvenous lead extraction and cardiac valve surgery during the PMA hospitalization were performed in 18.2% and 8.4% of admissions, respectively. The median hospital stay was 19.0 days, with 6.0% in-hospital mortality.

CONCLUSIONS

The marked increase in the number of PMA procedures in the United States suggests that this novel treatment option has been embraced as a useful tool in select cases of RSIE. More work is needed to better define indications for the procedure and its efficacy and safety.

Association of Intravenous Drug Use and Length of Stay Following Infective Endocarditis

INTRODUCTION

Intravenous drug use (IVDU) and associated infective endocarditis (IE) has been on the rise in the US since the beginning of the opioid epidemic. IVDU-IE has high morbidity and mortality, and treatment can be lengthy. We aim to quantify the association between IVDU and length of stay (LOS) in IE patients.

METHODS

The National Inpatient Sample database was used to identify IE patients, which was then stratified into IVDU-IE and non-IVDU-IE groups. Weighted values of hospitalizations were used to generate national estimates. Multivariable linear and logistic regression analyses were applied to estimate the effects of IVDU on LOS.

RESULTS

We identified 1,114,257 adult IE patients, among which 123,409 (11.1%) were IVDU-IE. Compared to non-IVDU-IE patients, IVDU-IE patients were younger, had fewer comorbidities, and had an overall longer LOS (median [interquartile range]: 10 [5-20] versus 7 [4-13] d, P < 0.001), with a greater percentage of patients with a LOS longer than 30 d (13.7% versus 5.7%, P < 0.001). After adjusting for multiple demographic and clinical factors, IVDU was independently associated with a 1.25-d increase in LOS (beta-coefficient = 1.25, 95% confidence interval [CI]: 0.95-1.54, P < 0.001) and 35% higher odds of being hospitalized for more than 30 d (odds ratio = 1.35, 95% CI: 1.27-1.44, P < 0.001).

CONCLUSIONS

Among IE patients, being IVDU has associated with a longer LOS and a higher risk of prolonged hospital stay. Steps toward the prevention of IE in the IVDU population should be taken to avoid an undue burden on the healthcare system.

Infective Endocarditis: Predictive Factors for Diagnosis and Mortality in Surgically Treated Patients

Background: Diagnosis of infective endocarditis (IE) often is challenging, and mortality is high in such patients. Our goal was to characterize common diagnostic tools to enable a rapid and accurate diagnosis and to correlate these tools with mortality outcomes. Methods: Because of the possibility of including perioperative diagnostics, only surgically treated patients with suspected left-sided IE were included in this retrospective, monocentric study. A clinical committee confirmed the diagnosis of IE. Results: 201 consecutive patients (age 64 ± 13 years, 74% male) were finally diagnosed with IE, and 14 patients turned out IE-negative. Preoperative tests with the highest sensitivity for IE were positive blood cultures (89.0%) and transesophageal echocardiography (87.5%). In receiver operating characteristics, vegetation size revealed high predictive power for IE (AUC 0.800, p < 0.001) with an optimal cut-off value of 11.5 mm. Systemic embolism was associated with mortality, and N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) had predictive power for mortality. Conclusion: If diagnostic standard tools remain inconclusive, we suggest employing novel cut-off values to increase diagnostic accuracy and accelerate diagnosis. Patients with embolism or elevated NT-proBNP deserve a closer follow-up.

Machine Learning-Based Risk Model for Predicting Early Mortality After Surgery for Infective Endocarditis

Background

The early mortality after surgery for infective endocarditis is high. Although risk models help identify patients at high risk, most current scoring systems are inaccurate or inconvenient. The objective of this study was to construct an accurate and easy‐to‐use prediction model to identify patients at high risk of early mortality after surgery for infective endocarditis.

Methods and Results

A total of 476 consecutive patients with infective endocarditis who underwent surgery at 2 centers were included. The development cohort consisted of 276 patients. Eight variables were selected from 89 potential predictors as input of the XGBoost model to train the prediction model, including platelet count, serum albumin, current heart failure, urine occult blood ≥(++), diastolic dysfunction, multiple valve involvement, tricuspid valve involvement, and vegetation >10 mm. The completed prediction model was tested in 2 separate cohorts for internal and external validation. The internal test cohort consisted of 125 patients independent of the development cohort, and the external test cohort consisted of 75 patients from another center. In the internal test cohort, the area under the curve was 0.813 (95% CI, 0.670–0.933) and in the external test cohort the area under the curve was 0.812 (95% CI, 0.606–0.956). The area under the curve was significantly higher than that of other ensemble learning models, logistic regression model, and European System for Cardiac Operative Risk Evaluation II (all, P<0.01). This model was used to develop an online, open‐access calculator (http://42.240.140.58:1808/).

Conclusions

We constructed and validated an accurate and robust machine learning–based risk model to predict early mortality after surgery for infective endocarditis, which may help clinical decision‐making and improve outcomes.

Tricuspid valve endocarditis: Cardiovascular imaging evaluation and management

Right-sided infective endocarditis is an increasingly recognized disease entity, with tricuspid valve being most frequently involved. Risk factors for tricuspid valve endocarditis (TVIE) include intravenous drug use, cardiac implantable electronic devices and indwelling catheters. Staphylococcus aureus is the predominant causative organism in TVIE. The diagnosis of infective endocarditis (IE) is based on clinical manifestations, blood cultures, and the presence of valvular vegetations detected by echocardiography. Complementary imaging is helpful when there is ongoing clinical suspicion for IE following initially negative echocardiography. Multislice computed tomography allows for assessment of extra-cardiac complications in TVIE, including pulmonary septic emboli. 18F-fluorodeoxyglucose positron emission tomography/computed tomography and radiolabelled white blood cell, single-photon emission computed tomography provide important clinical information concerning the presence of IE in right-sided prosthetic valves or cardiac implantable electronic devices. The aim of this review is to provide an update on TVIE, discussing the role of multimodality imaging in TVIE and the management of these patients.

Right-Sided Infective Endocarditis 2020: Challenges and Updates in Diagnosis and Treatment

Compared with the extensive data on left-sided infective endocarditis (IE), there is much less published information on the features and management of right-sided IE. Right-sided IE accounts for 5% to 10% of all IE cases, and compared with left-sided IE, it is more often associated with intravenous drug use, intracardiac devices, and central venous catheters, all of which has become more prevalent over the past 20 years. In this manuscript on right-sided IE we provide an up-to-date overview on the epidemiology, etiology, microbiology, potential locations of infection in the right heart, diagnosis, imaging, common complications, management, and prognosis. We present updated information on the treatment of pacemaker and device infections, infected fibrin sheaths that appear to be an easily missed source of infection after central line as well as pacemaker removal. We review current data on the AngioVac percutaneous aspiration device, which can obviate the need for surgery in patients with infected pacemaker leads and fibrin sheaths. We also focused on advanced diagnostic modalities, such as positron emission tomography/computed tomography. All of these are supported by specific case examples with detailed echocardiographic imaging from our experience.

Clinical Prognosis of Right-Sided Infective Endocarditis not Associated with Cardiac Devices or Intravenous Drug use: a Cohort Study and Meta-Analysis

Right-sided infective endocarditis (RSIE), classically associated with intravenous drug use or intracardiac devices, is considered a good-prognosis infective endocarditis (IE) form. However, predisposing factors and prognosis for "NODID" RSIE (NOt associated with cardiac Devices or Intravenous Drug use) remain unclear. The aim of this study was to evaluate predisposing factors and prognosis of NODID RSIE compared to other RSIE forms. A retrospective cohort study (January 2008-January 2019) was conducted in a reference center on 300 patients diagnosed with IE. Endocarditis-related events were defined as related to IE in mortality or open-heart surgery during follow-up. A review and meta-analysis of associated literature (January 2008-January 2019) were also performed. Fifty-seven patients presented RSIE (19%), 22 of which were NODID RSIE (39%). Use of intravascular catheters (23% vs 3%; p = 0.027) and congenital heart diseases (18% vs 0%; p = 0.019) were associated with NODID RSIE. This group had a higher in-hospital mortality (23% vs 3%; p = 0.027) and endocarditis-related event rates (41% vs 6%; p = 0.001) than non-NODID RSIE. Furthermore, NODID RSIE was independently associated with in-hospital endocarditis-related events (OR = 19.29; 95%CI:2.23-167.16; p = 0.007). Our meta-analysis evaluated four studies and identified 96 cases (30%) of NODID RSIE from 320 total RSIE cases. NODID RSIE patients demonstrated higher in-hospital mortality (RR = 2.81; 95%CI:1.61-4.90; p < 0.001; I2 = 0.0%) and necessity of open-heart surgery (RR = 13.89; 95%CI:4.14-46.60; p < 0.001; I2 = 0.0%) than non-NODID RSIE cases. Our study suggests that NODID RSIE has the highest endocarditis-related event rate and in-hospital mortality among RSIE cases and therefore should not be considered a good-prognosis IE.