Infective endocarditis in the 21st century

Current trends and challenges in infective endocarditis

PURPOSE OF REVIEW

Infective endocarditis (IE) is a complex disease with increasing global incidence. This review explores recent trends in IE infection patterns, including healthcare-associated IE (HAIE), drug-use-associated IE (DUA-IE), multidrug-resistant organisms (MDROs), and challenges in managing prosthetic valve and device-related infections.

RECENT FINDINGS

Staphylococcus aureus has emerged as the leading cause of IE, especially in HAIE and DUA-IE cases. Increasingly prevalent MDROs, such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, pose further clinical challenges. Advances in molecular diagnostics have improved the detection of culture-negative endocarditis. The introduction of the AngioVAC percutaneous aspiration device promises to change the management of right and possibly some left sided IE. Multidisciplinary team management and early surgery have demonstrated improved outcomes including partnerships with psychiatry and addictions services for those with intravenous DUA-IE.

SUMMARY

IE presents significant diagnostic and therapeutic challenges due to evolving infection patterns, MDROs, and HAIE. Early diagnosis using advanced imaging, appropriate early antimicrobial therapy, and multidisciplinary care, including timely surgery, are critical for optimizing patient outcomes.

Advancements and Challenges in the Management of Prosthetic Valve Endocarditis: A Review

Prosthetic valve endocarditis (PVE) is the medical term used to describe a focus of infection involving a valvular substitute within the heart. It is a significant concern in the field of cardiology, and the epidemiology of PVE has seen notable developments over the last five decades. The disease currently affects an older demographic and is becoming increasingly prevalent in patients with transcatheter-implanted valves. It is imperative that we urgently address the significant challenges posed by PVE. It is a disease that has a wide range of potential aetiologies, clinical presentations, and courses. In developed countries, Staphylococcus aureus is now the predominant causative organism, resulting in an aggressive form of disease that frequently afflicts vulnerable or elderly populations. However, it is clear that Enterococcus species present a significant challenge in the context of PVE following TAVR procedures, given their elevated prevalence. The 2023 Duke/International Society for Cardiovascular Infectious Diseases infective endocarditis diagnostic criteria now include significant developments in microbiological and image-based techniques for diagnostic purposes, specifically the incorporation of fluorine-18 fluorodeoxyglucose positron emission tomography and computed tomography. These developments unequivocally enhance the diagnostic sensitivity for PVE, while maintaining the specificity. They do so in accordance with the results of studies conducted specifically for the purpose of validation. The lack of rigorous scientific studies and a shortage of funding and resources for research have led to a significant gap in our understanding. Randomized controlled trials could provide invaluable insight and guidance for clinical practice, but they are missing, which represents a major gap. It is clear that there is an urgent need for more research. PVE is a life-threatening condition that must be handled by a multidisciplinary endocarditis team at a cardiac centre in order to improve outcomes. The emergence of innovative surgical techniques has empowered clinicians to steer more patients away from surgical procedures, despite the presence of clear indications for them. A select group of patients can now complete parenteral or oral antimicrobial treatment at home. Additionally, antibiotic prophylaxis is the best option for individuals with prosthetic valves who are going to have invasive dental procedures. These individuals should be given antibiotics beforehand.

Native Infective Endocarditis: A State-of-the-Art-Review

Native valve infective endocarditis (NVE) is a global phenomenon, defined by infection of a native heart valve and involving the endocardial surface. The causes and epidemiology of the disease have evolved in recent decades, with a doubling of the average patient age. A higher incidence was observed in patients with implanted cardiac devices that can result in right-sided infection of the tricuspid valve. The microbiology of the disease has also changed. Previously, staphylococci, which are most often associated with health-care contact and invasive procedures, were the most common cause of the disease. This has now been superseded by streptococci. While innovative diagnostic and therapeutic strategies have emerged, mortality rates have not improved and remain at 30%, which is higher than that for many cancer diagnoses. The lack of randomized trials and logistical constraints impede clinical management, and long-standing controversies such as the use of antibiotic prophylaxis persist. This state of the art review addresses clinical practice, controversies, and strategies to combat this potentially devastating disease. A multidisciplinary team will be established to provide care for patients with presumptive NVE. The composition of the team will include specialists in cardiology, cardiovascular surgery, and infectious disease. The prompt administration of combination antimicrobial therapy is essential for effective NVE treatment. Additionally, a meticulous evaluation of each patient is necessary in order to identify any indications for immediate valve surgery. With the intention of promoting a more comprehensive understanding of the procedural management of native infective endocarditis and to furnish clinicians with a reference, the current evidence for the utilization of distinct strategies for the diagnosis and treatment of NVE are presented.

Aortic root pseudoaneurysm: a case report and literature review

Pseudoaneurysms of the aortic root are rare. A case of prosthetic aortic valve infection progressing from a confined intramural abscess to a ruptured abscess communicating with the aorta and forming a large pseudoaneurysm is described. Additionally, data from all cases and case series, published between 2000 and 2021, was analyzed. A PUBMED search for the keywords "aortic root mycotic aneurysm," "aortic root abscess AND infective endocarditis," and "aortic root mycotic aneurysm AND infective endocarditis" yielded 152 publications (with 157 cases described): Aortic pseudoaneurysm is more common in males (80.9%, n = 127). Mean age is 51 years (4 months-84 years). The most common symptom is fever (68.5%, n = 102). Mean time until diagnosis is 27.2 days. Embolic complications are present in 17.8% (n = 28) at diagnosis. Most cases are due to valvular infections (n = 72 cases, 45.9%). Prior cardiac surgery is documented in 49.0% (n = 77). The mean time interval for developing aortic root abscess following heart surgery is 32.2 months. 22.3% (n = 35) are immunocompromised. Aetiological agents were Staphylococcus sp. (34.1%, n = 47) and Streptococcus sp. (23.2%, n = 32). Mean antimicrobial therapy lasts 58.5 days. Outcome with surgery is superior to medical treatment: overall inpatient mortality 18.5% (n = 27); with surgery 12.2% (n = 15 out of 123 patients), with only medical management 47.8% (n = 11 out of 23 patients). In conclusion, aortic root pseudoaneurysm occurs most commonly in middle-aged male patients. History of prior aortic procedures is commonly present. Correct diagnosis hinges on detailed history, transoesophageal echocardiography, and computed tomography (CT) aorta. Surgery is the preferred therapeutic option.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-023-01580-x.

Severe Tricuspid Regurgitation in a Patient With Previous Tricuspid Valve Surgery for Infective Endocarditis Secondary to Intravenous Drug Use: A Case Report

Tricuspid regurgitation (TR) is an important but underappreciated disease in medical practice, and the severity can vary from moderate to severe. Right-sided infective endocarditis (RSIE) is more common in intravenous drug users (IVDUs), and the vast majority of these involve the tricuspid valve (TV). It is worth mentioning that right-sided valves are challenging to scan compared to left-sided valves. The incidence of severe tricuspid regurgitation (TR) immediately post-repair is not tangible, but it is considered to be rare. We present a case of a 47-year-old patient who had previous TV septal leaflet reconstruction using a bovine pericardial patch using 6/0 prolene, and an annuloplasty was performed by placing an annuloplasty ring in 2017 for infective endocarditis. The patient developed moderate to severe tricuspid regurgitation within a few weeks following the surgery. She was readmitted to the hospital four years later with a reduced consciousness level, and a subsequent repeat echocardiogram showed possible tricuspid valve vegetation. In addition, transoesophageal echocardiogram (TOE) demonstrated biventricular dysfunction and severe tricuspid regurgitation, along with moderate to severe mitral regurgitation (MR) that was variable depending on the rate of atrial fibrillation. The patient was not suitable for surgical intervention and was medically managed accordingly.

Infective Endocarditis during Pregnancy-Keep It Safe and Simple!

The diagnosis of infective endocarditis (IE) during pregnancy is accompanied by a poor prognosis for both mother and fetus in the absence of prompt management by multidisciplinary teams. We searched the electronic databases of PubMed, MEDLINE and EMBASE for clinical studies addressing the management of infective endocarditis during pregnancy, with the aim of realizing a literature review ranging from risk factors to diagnostic investigations to optimal therapeutic management for mother and fetus alike. The presence of previous cardiovascular pathologies such as rheumatic heart disease, congenital heart disease, prosthetic valves, hemodialysis, intravenous catheters or immunosuppression are the main risk factors predisposing patients to IE during pregnancy. The identification of modern risk factors such as intracardiac devices and intravenous drug administration as well as genetic diagnostic methods such as cell-free deoxyribonucleic acid (DNA) next-generation sequencing require that these cases be addressed in multidisciplinary teams. Guiding treatment to eradicate infection and protect the fetus simultaneously creates challenges for cardiologists and gynecologists alike.

Infective Endocarditis in High-Income Countries

Infective endocarditis remains an illness that carries a significant burden to healthcare resources. In recent times, there has been a shift from Streptococcus sp. to Staphylococcus sp. as the primary organism of interest. This has significant consequences, given the virulence of Staphylococcus and its propensity to form a biofilm, rendering non-surgical therapy ineffective. In addition, antibiotic resistance has affected treatment of this organism. The cohorts at most risk for Staphylococcal endocarditis are elderly patients with multiple comorbidities. The innovation of transcatheter technologies alongside other cardiac interventions such as implantable devices has contributed to the increased risk attributable to this cohort. We examined the pathophysiology of infective endocarditis carefully. Inter alia, the determinants of Staphylococcus aureus virulence, interaction with host immunity, as well as the discovery and emergence of a potential vaccine, were investigated. Furthermore, the potential role of prophylactic antibiotics during dental procedures was also evaluated. As rates of transcatheter device implantation increase, endocarditis is expected to increase, especially in this high-risk group. A high level of suspicion is needed alongside early initiation of therapy and referral to the heart team to improve outcomes.

The New Challenge for Heart Endocarditis: From Conventional Prosthesis to New Devices and Platforms for the Treatment of Structural Heart Disease

Infective endocarditis is a sinister condition with considerable morbidity and mortality. Its relevance in the current era is compounded by the increased use of implanted devices such as replacement valves or cardiac implantable electronic devices. These infections are caused by multiple different bacteria with different virulence, pathogenicity, and antimicrobial resistance. Unlike in native endocarditis, the presence of foreign tissue permits sustenance by inflammatory and thrombotic processes as the artificial surfaces promote inflammatory responses and hypercoagulability. Prevention of these infections has been suggested with the use of homografts in combination with antibiotics. Others have attempted to use "low fouling coats" with little clinical success thus far. The use of antibiotic prophylaxis plays a pivotal part in reducing the incidence of prosthesis-related endocarditis. This remains especially crucial with the increasing use of transcatheter heart valve therapies. The widespread use of cardiac implantable electronic devices such as permanent pacemakers, implantable cardioverter defibrillators, and cardiac resynchronization therapy devices has also heralded a noticeable increase in cases of infectious endocarditis affecting complex equipment which can be difficult to treat. Multimodality strategies are needed with input from surgeons and cardiologists to ensure treatment is both prompt and successful, tailored to the individual needs of the patients.

Trends in Managing Cardiac and Orthopaedic Device-Associated Infections by Using Therapeutic Biomaterials

Over the years, there has been an increasing number of cardiac and orthopaedic implanted medical devices, which has caused an increased incidence of device-associated infections. The surfaces of these indwelling devices are preferred sites for the development of biofilms that are potentially lethal for patients. Device-related infections form a large proportion of hospital-acquired infections and have a bearing on both morbidity and mortality. Treatment of these infections is limited to the use of systemic antibiotics with invasive revision surgeries, which had implications on healthcare burdens. The purpose of this review is to describe the main causes that lead to the onset of infection, highlighting both the biological and clinical pathophysiology. Both passive and active surface treatments have been used in the field of biomaterials to reduce the impact of these infections. This includes the use of antimicrobial peptides and ionic liquids in the preventive treatment of antibiotic-resistant biofilms. Thus far, multiple in vivo studies have shown efficacious effects against the antibiotic-resistant biofilm. However, this has yet to materialize in clinical medicine.