Valve Infection Research Articles

First in-human study of 64Cu-DOTATATE positron emission tomography/computed tomography(PET/CT) in infective endocarditis: a prospective head-to-head comparison with 18-FDG PET/CT

Abstract Background Infective endocarditis (IE) is a severe and potentially fatal condition, which can be challenging to diagnose. Positron emission tomography/computed tomography (PET/CT) with [18F]fluorodeoxyglucose ([18F]FDG) is proposed as a diagnostic tool in the ESC endocarditis guidelines, but holds limitations. Purpose To compare the tracer uptake between [64Cu]Cu-DOTATATE and [18F]FDG in patients with IE, and to examine sensitivity and specificity in patients with prosthetic valve endocarditis (PVE) or native valve endocarditis (NVE). Methods The CuDOS-study was a prospective study including 20 cases with IE (10 with PVE and 10 with NVE) and 20 controls. [64Cu]Cu-DOTATATE and [18F]FDG PET/CT were performed in all participants. Scans were read blinded to clinical data. Tracer uptakes were measured as maximum standardized uptake values (SUVmax) in each heart valve. A visual interpretation of the presence or absence of IE was recorded for [64Cu]Cu-DOTATATE and [18F]FDG, respectively. Results The median age of the cases and controls was 68 years [IQR 53-71] and 61 years [IQR 56-67], respectively. In cases and controls, 85% and 70% were men, respectively. [64Cu]Cu-DOTATATE uptake (median SUVmax [IQR]) in patients with IE was higher than in controls (2.38 [1.87-2.90] vs. 1.43 [1.30-1.56], p<0.001), although this difference was mainly driven by PVE-cases (2.99 [2.22-3.75] vs. 1.43 [1.30-1.56 (controls), p<0.001) and to a lesser extent the NVE-cases (1.78 [1.22-2.33] vs. 1.43 [1.30-1.56 (controls), p=0.079), Figure 1. The sensitivity of [64Cu]Cu-DOTATATE and [18F]FDG PET/CT in 20 cases and the 20 controls were comparable, and the specificity was 90% and 75%, respectively. The analysis of PVE versus the 20 controls showed equal sensitivity (80%) for [64Cu]Cu-DOTATATE and [18F]FDG PET/CT and a specificity of 90% and 75%, respectively. The difference in the specificity between [64Cu]Cu-DOTATATE and [18F]FDG was 15% [IQR -5.9-36%], p=0.38. Conclusion [64Cu]Cu-DOTATATE PET/CT showed relevant uptake in the infected valve in patients with infective endocarditis. [64Cu]Cu-DOTATATE had a numerically higher specificity than [18F]FDG in prosthetic valve endocarditis, although the difference was not statistically significant. Both tracers were limited in the detection of native valve endocarditis.Figure 1 [64Cu]Cu-DOTATATE and [18F]FDG

Postoperative heart valve infection, when and which bacteria: a nationwide cohort study

Abstract Background In patients undergoing heart valve surgery, subsequent bacteremia and infective endocarditis are feared events due to the associated high mortality. Knowledge on the incidence and specification of bacteremia following left-sided valve surgery are sparse and may have implications for prophylactic strategies and follow-up. Purpose To examine the six months incidence of bacteremia and infective endocarditis following left-sided heart valve surgery. Methods In the period from January 2010 to December 2021 all patients undergoing left-sided valve surgery were identified using Danish nationwide registries. Patients were followed until a maximum of six months, end of study, emigration, death, or outcome of interest (i.e., bacteremia or infective endocarditis). Cumulative incidence curves were computed with death as a competing risk stratified on bacterial species and for subgroups of interest: type of valve surgery, age, and sex. Results A total of 14,305 patients were included in the study. The majority of the study population were male (68.6%), and the median age was 70.2 years (25th-75th percentile 62.0-76.0 years). In total, 10,469 (73.2%) of the study population underwent aortic valve surgery, 3,497 (24.5%) underwent mitral valve surgery, while 339 (2.4%) underwent surgery on both valves. The cumulative incidence of bacteremia at six months of follow-up was 2.4% (95% CI 2.2-2.7%), Figure 1. For the overall study population, the most frequently occurring bacteremia was with Coagulase-negative Staphylococci (28%) and Staphylococcus aureus (14%). Within 30 days 0.35% of the patients had bacteremia with coagulase-negative staphylococci while this was 0.68% at six months of follow-up. For Staphylococcus aureus this was 0.19% and 0.34%, respectively. The cumulative incidence of infective endocarditis at six months of follow up was 1.0% (95% CI 0.8-1.2%). The majority of the infective endocarditis incidents were blood culture negative (27%) or caused by Enterococci (19%), Streptococci (17%) or Coagulase-negative Staphylococci (17%) while Staphylococcus aureus accounted for 14%. In crude analysis, simultaneous surgery on the mitral and aortic valve was associated with a statistically significant higher rate of bacteremia (P=0.004). Similarly, higher age was associated with a statistically significant higher rate of bacteremia (P<0.001). On the contrary, in crude analysis, no difference in the risk of bacteremia was found between sexes (P=0.9). Conclusions Bacteremia following left-sided heart valve surgery occurred in little over 2%. The majority was with Staphylococci, and half of these occurred within 30 days of the surgery. There is a continued need to optimize prophylactic strategies.

Outpatient parenteral antimicrobial therapy for patients with Enterococcus faecalis endocarditis using continuous infusion IV benzylpenicillin plus IV ceftriaxone.

Many patients with Enterococcus faecalis endocarditis are clinically stable and able to leave hospital before completing antibiotic treatment, but data are lacking regarding some outpatient treatment options. To assess the outcomes for adults with E. faecalis endocarditis receiving outpatient parenteral antimicrobial therapy (OPAT) with continuous infusion IV benzylpenicillin plus bolus/continuous infusion IV ceftriaxone. We retrospectively reviewed adults who received at least 2 weeks duration of OPAT for E. faecalis endocarditis with the above treatment regimen in the Auckland and Christchurch regions between July 2019 and September 2022. Forty-four patients met inclusion criteria. Fifteen were female (34%). The median age was 80 (IQR 71.5 to 84) years. Twenty-two (50%) had prosthetic valve (PV), 15 (34%) native valve (NV), 3 (7%) NV and/or cardiac implantable electronic device (CIED) infection, 3 (7%) PV and/or CIED infection, and 1 (2%) repaired valve endocarditis. Patients received a median of 16.5 days inpatient and 28 days OPAT antibiotic treatment. The 12 month outcome was cure (n = 25; 57%), antibiotic suppression (n = 9; 20%), relapse (n = 2; 5%; both possible) or death (n = 8; 18%). Compared with a historical cohort treated with OPAT continuous infusion IV benzylpenicillin plus bolus IV gentamicin, there was no difference in the relapse rate. This study adds to the accumulating evidence supporting the treatment of E. faecalis endocarditis with OPAT continuous infusion IV benzylpenicillin plus bolus/continuous infusion IV ceftriaxone. This is an option for patients requiring further antibiotic treatment at the time of hospital discharge.

Biodegradable annuloplasty rings: evolution, characteristics and surgical technique

Annulus remodeling and stabilization with a ring have been demonstrated to be a mandatory step in mitral and tricuspid valve repair to ensure effective leaflet coaptation and improve long-term results. The need for a degradable ring stems from two areas in which biodegradable ring annuloplasty can theoretically fill a void: 1 – valve repair in infected valve tissue to avoid colonization of permanent implanted ring device and infection recurrence, 2 – valve repair in children, where traditional annuloplasty rings can’t be used due to the risk of acquired stenosis for lack of growth. Prophylactic anticoagulation following biodegradable ring annuloplasty is not necessary, provided that the patient has no other indication for it, as the intraannular position of the ring protects against any «blood-biodegradable ring» interaction.

Clinical Characterization of Pathogens, Risk Factors and Quality of Life in an Observational Study of Native vs. Prosthetic Aortic Valve Endocarditis Surgery.

Background: Native (NVE) and prosthetic (PVE) aortic valve endocarditis (AVE) remain a surgical challenge with an ongoing trend towards more complex surgical procedures. Methods: First-time NVE was compared with PVE, focusing on pathogens, risk factors, perioperative course, postoperative follow-up, including recurrent infection, as well as health-related quality of life (HRQOL). Results: From 2007 to 2022, surgical intervention for AVE was necessary in 231 patients with 233 episodes of infective aortic valve endocarditis, i.e., there were only two cases of reinfection (NVE group). The study group consisted of 130 cases with NVE and 103 with PVE. Overall, a median of 40.3% of survivors were in NYHA class I or II. In-hospital mortality was higher in the PVE group with 13.3%. The most common pathogen was Staphylococcus aureus, with 24.9% across both groups. EuroSCORE II was higher in the PVE group (19.0 ± 14.3% total, NVE 11.1 ± 8.1%, PVE 27.8 ± 14.6%; p < 0.05), reflecting an older, more co-morbid patient cohort. Abscess formation was also more common in the PVE group, while vegetations were more common in the NVE group. The 5-year and 10-year survival rates did not differ significantly between NVE and PVE and were 74.4% and 52.2% for the NVE group, respectively, and 67.4% and 52.9% for the PVE group, respectively. The HRQOL as assessed by the Minnesota Living with HF Questionnaire (MLHFQ) demonstrated no significant difference between both groups. Conclusions: Long-term survival and QoL after surgical treatment of infective aortic valve endocarditis are excellent and do not depend on the type of replacement.

Utilizing a sutureless valve for prosthetic valve endocarditis after aortic root replacement

BackgroundReoperation following aortic root replacement is associated with significantly high operative mortality. Etiologies related to infection are known to increase the operative mortality rate more than other etiologies. In such a clinical setting, a sutureless valve could lower the operative mortality by shortening the cardiac arrest and the operative time.Case presentationA 61-year-old male underwent emergent aortic root and total arch replacement with an open stent graft for acute type-A aortic dissection. A bioprosthetic valve was employed for aortic root replacement using the double-sewing ring technique. A fungal infection by Candida parapsilosis was postoperatively detected and improved with intravenous antifungal drug administration. However, he developed congestive heart failure one year later, and the blood cultures turned positive repeatedly for Candida parapsilosis. The prosthetic valve infection was suspected upon identifying vegetation on the bioprosthetic valve through transthoracic echocardiography. The computed tomography scan and operative findings confirmed that the infection was localized on the prosthetic valve. Consequently, the infected valve was removed without a vascular conduit, and a sutureless valve was implanted. The postoperative course was uneventful, without any evidence of recurrent fungal infection, and the patient was discharged on postoperative day 28.ConclusionsDeploying a sutureless valve can facilitate a more straightforward and minimally invasive redo procedure. Preoperative computed tomography can predict the valve size, which is the key to implanting a sutureless valve successfully after the modified Bentall procedure.

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.

Contemporary Role of Positron Emission Tomography (PET) in Endocarditis: A Narrative Review.

Endocarditis, a serious infectious disease, remains a diagnostic challenge in contemporary clinical practice. The advent of advanced imaging modalities has contributed significantly to the improved understanding and management of this complex disease. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) imaging has shown remarkable potential in improving the diagnostic accuracy of endocarditis. In the update of the Modified Duke Criteria, in 2023, The International Society for Cardiovascular Infectious Diseases (ISCVID) Working Group recognized specific 18F-FDG PET/CT findings as a major diagnostic criterion, particularly in patient with prosthetic valve endocarditis. The ability of PET to visualize metabolic activity allows for the identification of infective foci and could differentiate between infective and non-infective processes. This review examines the clinical utility of PET in differentiating infective endocarditis from other cardiovascular pathologies, highlighting its sensitivity and specificity in detecting native and prosthetic valve infections, including patients with transcatheter aortic valve implantation (TAVI), cardiac implantable devices (CIEDs), and left ventricular assistance devices (LVAD). Also, practical aspects and indications are illustrated to optimize the quality of imaging and reduce potential false positive results. In conclusion, the current use of PET in endocarditis has become a valuable diagnostic tool; as technological advances continue, PET will play an increasingly important role in the multidisciplinary approach to the management of endocarditis.

129 ANCA-associated pauci-immune crescentic necrotizing glomerulonephritis triggered by Bartonella henselae infective pulmonic valve endocarditis confirmed by 18 F-FDG PET/CT scan

129 ANCA-associated pauci-immune crescentic necrotizing glomerulonephritis triggered by Bartonella henselae infective pulmonic valve endocarditis confirmed by 18 F-FDG PET/CT scan

Treatment of Late Infective Prosthetic Endocarditis Complicated by Cerebral Infarction with Vegetations: Pharmacotherapeutic Approach (Case Report)

Prosthetic endocarditis is a serious complication in a long term. Vegetation as a thromboembolic complication leads to neurologic deficit varying in severity.&#x0D; Case description. A 35-year-old female patient F. underwent surgical treatment at the Department of Surgical Treatment of Acquired Heart Diseases of the National Amosov Institute of Cardiovascular Surgery on September 07, 2016: aortic valve replacement with wrapping tape operation II. The patient was discharged from the hospital on the 9th day after surgery in a satisfactory condition. On November 20, 2019, the patient was admitted to the Institute with the diagnosis of late infective prosthetic aortic valve endocarditis, status post aortic valve replacement and wrapping tape operation in 2016, first-degree atrioventricular block, cerebral infarctions in multiple locations with hemorrhagic transformation, with aphasia elements, ataxia, right-sided pyramidal insufficiency and suspected meningitis. After 21 days of drug therapy, the patient responded to treatment successfully and was discharged from the hospital in a satisfactory condition without surgical treatment.&#x0D; Conclusions. Taking into consideration the serious condition of the patient, timely and carefully selected drug therapy can be the correct solution for the treatment of patients with late infective endocarditis. Thus, surgery is not always the treatment of choice.

Хирургическое лечение инфекционного эндокардита аортального клапана

Хирургическое лечение инфекционного эндокардита аортального клапана

Peripheral white blood cell patterns in children with hydrocephalus as a response to ventriculo-peritoneal shunt infection.

Shunt infection is one of the most common complications of conventional hydrocephalus treatment. The route of invasion of a pathogen can modify the immune response of the CNS. The aim of the study is to analyze the immune response to shunt infection caused by S. epidermidis in children with hydrocephalus. The immune response to the pathogen will be analyzed on the basis of, inter alia, simple laboratory test results, such as changes in the pattern of white blood cells, including neutrophils, monocytes, and lymphocytes. The entire study analyzes changes in general parameters of the cerebrospinal fluid (pleocytosis, protein level, glucose level) and in levels of selected interleukins (IL-6, CXCL8 / IL-8, CCL3 / MIP-1a) in the cerebrospinal fluid. The clinical material analyzed in the study was collected in 2010-2014. The study group consisted of 30 patients, who were admitted to the hospital due to their first-ever episode of valve dysfunction caused by S. epidermidis infection. The control group consisted of 30 children who also suffered from congenital hydrocephalus but had not been operated on before. The most pronounced response to CSF infection in the study group was a significant increase in the counts of all investigated WBC lines in the samples collected immediately after the patients' admission to the ward. The earliest aberration of the CSF was a significant increase in protein level. An infection of a ventriculoperitoneal shunt caused by S. epidermidis evokes a very early peripheral blood response. In children affected by a ventriculoperitoneal valve infection, the humoral immune response detected in the cerebrospinal fluid precedes the increase in the level of pleocytosis. The highest level of cytokines in the cerebrospinal fluid is achieved when the pathogens are cleared. Phagocytes, and, in particular, monocytes, play an important role in the normalization of the cerebrospinal fluid parameters after the elimination of S. epidermidis. The local immune response of the central nervous system plays an important role in extinguishment of the inflammatory process.

Features of infective endocarditis in a contemporary cohort of persons who inject drugs: a matched comparison analysis of long-term prognostic factors.

The objective of the study was to assess the short- and long-term mortality of infective endocarditis (IE) among people who inject drugs (PWID). Using prospectively collected data on hospitalized patients (years 2000 through 2021) with IE, PWID were identified and included in this study. Survival analysis was performed to analyze short- and long-term mortality and study their risk factors among PWID and a matched group of non-intravenous drug users (N-IDU). In a study of 485 patients admitted for IE, 55 (11%) of them were PWID. These PWID patients were 1:1 age- and sex- matched to an N-IDU group (N = 55 per group). Both groups had similar baseline comorbid conditions, including congestive heart failure, type 2 diabetes, and neoplastic diseases. However, PWID were more likely to have HCV co-infection (62% vs 16%, respectively, p < 0.001) and advanced liver disease/cirrhosis (52% vs 7.9%, respectively, p < 0.001). IE in PWID more often affected the tricuspid valve (42% vs 22%, respectively, p = 0.024) and presented with more embolic events (66% vs 35%, respectively, p < 0.01). S. aureus was the primary cause of IE in PWID (44% vs 21%, respectively, p = 0.01). After adjusting for other variables, PWID (HR = 2.99, 95% CI [1.06, 8.43], p = 0.038) and valve bioprosthetic replacement (HR = 5.37, 95% CI [1.3, 22.1], p = 0.02) were independently associated with increased mortality risk, whereas IE caused by tricuspid valve infection was associated with reduced mortality risk (HR = 0.25, 95% CI [0.06, 0.97], p = 0.046). In this cohort, PWID had increased risk of long-term mortality after hospital discharge for IE, when compared to matched N-IDU with similar baseline characteristics. The reasons behind the significant increase in mortality warrant further investigation.

Endocarditis caused by Aspergillus fumigatus in a patient 9 months after COVID-19 infection recovery: a case report and review of the literature

BackgroundAspergillus spp. are among the fungal pathogens that can cause life-threatening infections in patients with a history of COVID-19.Case presentationWe present the case of a 58-year-old Iranian woman with post-COVID-19 Aspergillus fumigatus endocarditis complicated by numerous thromboembolisms. She underwent mitral valve replacement surgery and multiple lower extremity embolectomies and was treated with voriconazole, which led to her final recovery.ConclusionsAspergillus endocarditis should be considered in any patient with suspected endocarditis who has a history of COVID-19 infection and does not respond to routine antibiotic and antifungal therapy, as COVID-19 interferes with proper immune function, and lack of underlying cardiac conditions and immunodeficiencies does not preclude the diagnosis. Culture and histopathological evaluation of vegetations and emboli, as well as PCR, can confirm the diagnosis. Early initiation of antifungal therapy and surgical removal of infected valves and emboli can improve prognosis in patients with Aspergillus endocarditis.

2200. The Antibiotic Steward's Nightmare: Long-Term Antibiotics in An Infectious Disease Practice

Abstract Background The effects of long-term antibiotic use, including the frequency of recurrent infections and new-onset resistant infections, are not fully understood. The role of antibiotics in the disruption of the gut microbiota has been well-described, impacting insulin susceptibility and lipid deposition. Prolonged antibiotic use may have potential to be implicated in obesity, diabetes, and hyperlipidemia. There may also be an effect on the incidence of secondary infections with new organisms, the frequency of breakthrough infections from the index organism, and the selection for resistant infections. Methods This retrospective study evaluated 78 patients seen at an outpatient infectious disease practice. Inclusion criteria were patients with prescription of an oral antibiotic for 90 or more consecutive days between 9/1/18 and 12/31/2019, who utilize a health system pharmacy. Data was collected from patient charts at baseline prior to antibiotic initiation, and at time of most recent follow up after the initiation of antibiotic. Results Cephalexin (37.2%), azithromycin (34.6%) and amoxicillin (12.8%) were the most common antibiotics prescribed. Mean patient age was 69.4 years. Indications for antibiotic use included NTM infections (34.6% of cases), prosthetic joint infections (21.8%), recurrent UTIs (10.3%), and prosthetic valve infection (7.7%). 23.4% of patients experienced breakthrough infection with the index organism, while 21.8% experienced new, unrelated infection during follow-up, of which 52.9% had a resistant organism isolated. Mean BMI at baseline was 26.9, and BMI at follow-up was 27.3. The difference between baseline and follow-up BMI was not statistically significant (p=0.177). A1C, LDL, and cholesterol rose from baseline to follow-up, but did not reach statistical significance. Conclusion Patients on long-term antibiotics had a numerical increase in BMI, A1C, LDL, and cholesterol values following initiation, but those increases were not statistically significant. Recurrence of infection and emergence of resistance was common. The small sample size and limitation of studying patients from one practice within one health system pharmacy are limitations of the study. Further studies with larger sample sizes and comparative groups by diagnosis are needed. Disclosures All Authors: No reported disclosures

Caseous calcification of the mitral annulus

Caseous calcification of the mitral annulus (CCMA) is a rare form of degenerative lesion of the mitral valve fibrous ring. It’s a biochemical transformation of calcification area accompanied with formation of masses of a curdled consistency (caseosis). It is usually located in the area of the posterior mitral valve. In most cases, it is asymptomatic or minimally symptomatic, and is an incidental finding during imaging studies. The causes and pathogenesis of CCMA are unknown, however, there is a connection with disorders of calcium and phosphorus metabolism and there is no connection with an valve infection. There is no specific treatment. In cases where CCMA leads to significant disturbances of cardiac hemodynamics and/or there is a high probability of ebolism, it needs to be treated surgically.Differential diagnosis is carried out with other cardiac mass.

Abstract 14907: Trends in Management Practices of Cardiovascular Implantable Electronic Device Infections in Patients With End-Stage Kidney Disease

Introduction: End-stage kidney disease (ESKD) patients with cardiovascular implantable electronic devices (CIEDs) are at higher risk of bloodstream infection. While prior studies have shown high procedural success rates of lead extraction and improved outcomes, the rates of lead extraction in these patients at the national level are not known. Aim: To evaluate trends in management practices of CIED infections in ESKD patients. Methods: Utilizing the United States Renal Data System and ICD 9 codes, we identified patients aged &gt;18 years with ESKD on hemodialysis who underwent first CIED implant from January 2006-September 2014. For study purposes we studied management strategy in those who developed CIED infection within 1 year of device implant. We excluded patients with a prosthetic valve as the ICD 9 code for CIED infection also includes prosthetic valve infection. We restricted the study population to those with CIED implanted until September 2014 as ICD 10 codes were implemented in September 2015 and the ICD 10 code is not specific code for CIED infection (it also includes vascular device infections). After identifying patients diagnosed with CIED infection, we utilized procedure codes for lead extraction within 60 days of the infection diagnosis to determine the mode of management. In the absence of procedure codes for extraction, patients were presumed to have been managed medically. Results: A total of 380 ESKD patients undergoing CIED implant from 2006-2014 were diagnosed with CIED infections within 1 year of device implant. Of these, 183 (48.16%) patients underwent lead extraction within 60 days. When analyzed by year, the rates of utilization of lead extraction in these patients have not changed significantly from 2006 to 2015 (Table). Conclusions: The utilization of lead extraction for management of CIED infections in ESKD patients remains low (~50%). This data calls for a reassessment of management strategy for device infections in ESKD patients.

A self-assembled implantable microtubular pacemaker for wireless cardiac electrotherapy.

The current cardiac pacemakers are battery dependent, and the pacing leads are prone to introduce valve damage and infection, plus a complete pacemaker retrieval is needed for battery replacement. Despite the reported wireless bioelectronics to pace the epicardium, open-chest surgery (thoracotomy) is required to implant the device, and the procedure is invasive, requiring prolonged wound healing and health care burden. We hereby demonstrate a fully biocompatible wireless microelectronics with a self-assembled design that can be rolled into a lightweight microtubular pacemaker for intravascular implantation and pacing. The radio frequency was used to transfer energy to the microtubular pacemaker for electrical stimulation. We show that this pacemaker provides effective pacing to restore cardiac contraction from a nonbeating heart and have the capacity to perform overdrive pacing to augment blood circulation in an anesthetized pig model. Thus, this microtubular pacemaker paves the way for the minimally invasive implantation of leadless and battery-free microelectronics.

Health Care Associated Infective Endocarditis in Hemodialysis: More than Just Valve Infection- A Case Series

Cardiovascular diseases and infections are the two main causes of mortality in Hemodialysis patients [1, 6]. Health care associated infective endocarditis among them carries higher morbidity and mortality. The following is a case series of 3 Enterococcal endocarditis in HD patients and our experience in the management.

A Literature Review on the Use of Aortic Allografts in Modern Cardiac Surgery for the Treatment of Infective Endocarditis: Is There Clear Evidence or Is It Merely a Perception?

Infective valve endocarditis is caused by different pathogens and 60% of those involve the aortic valve with valve failure. Although S. aureus is recognized as the most frequently isolated causative bacterium associated with IE in high-income countries, Gram-positive cocci nevertheless play a crucial role in promoting infection in relation to their adhesive matrix molecules. The presence of pili on the surface of Gram-positive bacteria such as in different strains of Enterococcus faecalis and Streptococcus spp., grants these causative pathogens a great offensive capacity due to the formation of biofilms and resistance to antibiotics. The indications and timing of surgery in endocarditis are debated as well as the choice of the ideal valve substitute to replace the diseased valve(s) when repair is not possible. We reviewed the literature and elaborated a systematic approach to endocarditis management based on clinical, microbiological, and anatomopathological variables known to affect postoperative outcomes with the aim to stratify the patients and orient decision making. From this review emerges significant findings on the risk of infection in the allograft used in patients with endocarditis and no endocarditis etiology suggesting that the use of allografts has proved safety and effectiveness in patients with both pathologies.