Infective endocarditis after transcatheter aortic valve implantation: results from a large multicenter registry

Infection of Transcatheter Valvular Devices

PURPOSE OF REVIEW

This review explores the epidemiology, clinical traits, and diagnosis of Transcatheter Aortic Valve Replacement-Associated Infective Endocarditis (TAVR-IE) and mitral transcatheter edge-to-edge repair infective endocarditis (TEER-IE), focusing on a multimodal imaging approach. It addresses the rising prevalence of TAVR and TEER, emphasizing the need to understand long-term complications and clinical consequences, which poses significant challenges despite advancements in valve technology.

RECENT FINDINGS

Studies report a variable incidence of TAVR-IE and TEER-IE influenced by diverse patient risk profiles and procedural factors. Younger age, male gender, and certain comorbidities emerge as patient-related risk factors. Procedure-related factors include intervention location, valve type, and technical aspects. Microbiologically, Staphylococcus aureus, Viridans Group Streptococcus, and Enterococcus are frequently encountered pathogens. TAVR-IE and TEER-IE diagnosis involves a multimodal imaging approach due to limitations in echocardiography. Blood cultures and imaging aid identification, with Fluorescence in situ hybridization is showing promise. Treatment encompasses medical management with antibiotics and, when necessary, surgical intervention. The management approach requires a multidisciplinary "Endocarditis Team." This review underscores the need for continued research to refine risk prediction, enhance diagnostic accuracy, and optimize management strategies for TAVR-IE, considering the evolving landscape of transcatheter interventions.

Surgical Therapy of Infective Prosthesis Endocarditis following TAVI: A Single Center's Experience

BACKGROUND/OBJECTIVES

Infective prosthesis endocarditis (IE) following transcatheter aortic valve implantation (TAVI) presents significant management challenges, marked by high mortality rates. This study reviews our center's experience with surgical interventions for IE in patients post-TAVI, focusing on outcomes, challenges, and procedural complexities, and providing an overview of the limited literature surrounding this subject.

METHODS

This study was executed as a comprehensive retrospective analysis, targeting the clinical outcomes of surgical treatment in patients presenting with PVE following TAVI procedures at our institution. From July 2017 to July 2022, we identified five patients who had previously undergone transfemoral transcatheter aortic valve implantation and were later diagnosed with PVE needing surgery, strictly adhering to the modified Duke criteria.

RESULTS

All surgical procedures were reported successful with no intra- or postoperative mortality. Patients were predominantly male (80%), with an average age of 76 ± 8.6 years, presenting mostly with dyspnea (NYHA Class II). The mean follow-up was between 121 and 1973 days, with outcomes showing no occurrences of stroke, myocardial infarction, or major bleeding. One patient expired from unrelated causes 3.7 years post-surgery. The operative and postoperative protocols demonstrated effective disease management with enhanced survival and minimal complications.

CONCLUSIONS

The surgical treatment of IE following TAVI, though challenging, can be successfully achieved with careful patient selection and a multidisciplinary approach. The favorable outcomes suggest that surgical intervention remains a viable option for managing this high-risk patient group. Our study also highlights the scarce literature available on this topic, suggesting an urgent need for more comprehensive research to enhance understanding and improve treatment strategies. Future studies with larger cohorts are needed to further validate these findings and refine surgical strategies for this growing patient population.

Enterococcal Infective Endocarditis - Post discharge treatment with continuous benzylpenicillin and ceftriaxone: A retrospective cohort study

BACKGROUND

Enterococcal Infective Endocarditis (EIE) is usually treated with the combination of penicillin/ampicillin with gentamicin or ampicillin with ceftriaxone. To enable prolonged outpatient treatment, a combination of benzylpenicillin and ceftriaxone has been suggested. This study aimed to describe the incidence and characteristics of EIE and to determine the outcome of EIE cases treated with benzylpenicillin and ceftriaxone.

METHODS

This was a retrospective single-center study including all patients diagnosed with infective endocarditis (IE) during 2016-2021, comparing EIE with IE caused by other pathogens. We described the outpatient treatment of patients with EIE, comparing those treated of benzylpenicillin - ceftriaxone with other regimes.

RESULTS

Among 222 patients with IE, 44 (20%) were diagnosed with EIE. Those were older, had a male predominance (p = 0.035), and were more disabled (p = 0.004). The incidence of EIE reached 30% towards the last year, becoming the leading etiology. Twenty-six patients received outpatient treatment, five of whom were discharged with benzylpenicillin and ceftriaxone. Adding patients from this cohort to the scarce data available, revealed similar recurrence and mortality rates compared to other treatment regimes.

CONCLUSIONS

EIE is becoming a more frequent cause of IE, involving older, more disabled patients with male predominance. Our experience and existing literature suggest that the combination of benzylpenicillin and ceftriaxone is as safe as more conventional regimes, although further research is needed.

Heart transplantation in a patient with infective endocarditis bridged with Impella 5.5: a case report

Background

Infective endocarditis (IE) is a feared complication after surgical valve replacement accounting for 10% to 30% of all cases of IE. Our case is unique as we present a decompensated heart failure patient with IE who urgently needed mechanical circulatory support (MCS) to stabilize while IE was treated. We used Impella to bridge him to sterile state before heart transplant was done. This case highlights the importance of different strategies for bridge to heart transplant in decompensated heart failure patients with endocarditis.

Case summary

We describe a case of 62-year-old male who initially presented with severe shortness of breath with minimal exertion, weight gain, and lower extremity oedema diagnosed with acute on chronic systolic heart failure (HF) exacerbation (ACC stage D, NYHA class IV). Initial blood cultures and extensive work-up for IE were negative. He continued to decompensate haemodynamically despite inotropic support and the decision was to proceed with durable left ventricular assist device (LVAD) as bridge to orthotopic heart transplantation (OHT). Immediately prior to LVAD implantation, patient's blood cultures became positive for Cutibacterium acnes. Echocardiogram revealed IE on bioprosthetic aortic valve. Patient therefore underwent urgent aortic valve replacement (AVR) and was stabilized with Impella 5.5.

Discussion

We highlight a case where MCS with Impella was used as a bridge to transplant in a decompensated HF patient who was septic. Patient was listed for OHT but was found to be septic due to IE and had to undergo AVR to achieve infection source control prior to undergoing heart transplant. Impella was used effectively to stabilize ACC stage D/NYHA class IV patient while he recovered from AVR and endocarditis before his blood cultures cleared up and he was listed for OHT. He successfully underwent OHT after 3 weeks.

Infective endocarditis after isolated aortic valve replacement: comparison between catheter-interventional and surgical valve replacement

BACKGROUND AND AIMS

Prosthetic valve endocarditis (PVE) is the prognostically most unfavourable complication after aortic valve replacement. This study aims to contribute to a better understanding of the different pathological and therapeutical aspects between PVE following surgical (SAVR) and transcatheter aortic valve replacement (TAVI).

METHODS

All patients who had undergone primary isolated SAVR (n = 3447) or TAVI (n = 2269) at our Centre between 01/2012 and 12/2018 were analysed. Diagnosis of PVE was based on Duke criteria modified in 2015. Incidence, risk factors, pathogens, impact of complications or therapy on mortality were analysed and compared between SAVR- and TAVI-PVE.

RESULTS

PVE incidence did not differ significantly after SAVR with 4.9/100 patient-years and TAVI with 2.4/100 patient-years (p = 0.49), although TAVI patients were older (mean 80 vs. 67 years) and had more comorbidities (STS score mean 5.9 vs. 1.6) (p < 0.001). TAVI prostheses with polymer showed a 4.3-fold higher risk to develop PVE than without polymer (HR 4.3; p = 0.004). Most common pathogens were staphylococci and enterococci (p > 0.05). Propensity-score matching analysis showed that the type of aortic valve replacement had no effect on the development of post-procedural PVE (p = 0.997). One-year survival was higher in TAVI-PVE patients treated with antibiotics only compared to additional surgical therapy (90.9% vs. 33.3%; p = 0.005). In SAVR-PVE patients, both therapies were comparable in terms of survival (p = 0.861). However, SAVR-PVE patients who were not operated, despite ESC-guideline recommendation, had significantly poorer one-year survival (p = 0.004).

CONCLUSION

TAVI patients did not have a significantly higher risk to develop PVE. Our data suggest that TAVI-PVE patients in contrast to SAVR-PVE patients can more often be treated with antibiotics only, presumably due to the lack of a polymeric suture ring.

Multimodality Imaging Diagnosis in Infective Endocarditis

Imaging is an important tool in the diagnosis and management of infective endocarditis (IE). Echocardiography is an essential examination, especially in native valve endocarditis (NVE), but its diagnostic accuracy is reduced in prosthetic valve endocarditis (PVE). The diagnostic ability is superior for transoesophageal echocardiography (TEE), but a negative test cannot exclude PVE. Both transthoracic echocardiography (TTE) and TEE can provide normal or inconclusive findings in up to 30% of cases, especially in patients with prosthetic devices. New advanced non-invasive imaging tests are increasingly used in the diagnosis of IE. Nuclear medicine imaging techniques have demonstrated their superiority over TEE for the diagnosis of PVE and cardiac implantable electronic device infective endocarditis (CIED-IE). Cardiac computed tomography angiography imaging is useful in PVE cases with inconclusive TTE and TEE investigations and for the evaluation of paravalvular complications. In the present review, imaging tools are described with their values and limitations for improving diagnosis in NVE, PVE and CIED-IE. Current knowledge about multimodality imaging approaches in IE and imaging methods to assess the local and distant complications of IE is also reviewed. Furthermore, a potential diagnostic work-up for different clinical scenarios is described. However, further studies are essential for refining diagnostic and management approaches in infective endocarditis, addressing limitations and optimizing advanced imaging techniques across different clinical scenarios.

Endocarditis after Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) use is gaining momentum as the mainstay for the treatment of aortic stenosis compared to surgical aortic valve replacement (SAVR). Unfortunately, TAVR-related infective endocarditis (TAVR-IE) is expected to be detected more and more as a result of the ever-expanding indications in younger patients. Given the overall poor prognosis of TAVR-IE, it is imperative that clinicians familiarize themselves with common presentations, major risk factors, diagnostic pitfalls, therapeutic approaches, and the prevention of TAVR-IE. Herein, we review all of the above in detail with the most updated available literature.

Bridging Molecular and Clinical Sciences to Achieve the Best Treatment of Enterococcus faecalis Endocarditis

Enterococcus faecalis (E. faecalis) is a commensal bacterium that causes various infections in surgical sites, the urinary tract, and blood. The bacterium is becoming a significant concern because it tends to affect the elderly population, which has a high prevalence of undiagnosed degenerative valvular disease and is often subjected to invasive procedures and implanted medical devices. The bacterium's actions are influenced by specific characteristics like pili activity and biofilm formation. This resistance significantly impedes the effectiveness of numerous antibiotic therapies, particularly in cases of endocarditis. While current guidelines recommend antimicrobial therapy, the emergence of resistant strains has introduced complexity in managing these patients, especially with the increasing use of transcatheter therapies for those who are not suitable for surgery. Presentations of the condition are often varied and associated with generalised symptoms, which may pose a diagnostic challenge. We share our encounter with a case study that concerns an octogenarian who had a TAVI valve and developed endocarditis. We also conducted a literature review to identify the essential treatment algorithms for such cases.

Patients with Artificial Heart Valves

BACKGROUND

In Germany, a total of 38 547 heart valve procedures were performed in 2022. With a growing number of patients undergoing the surgical and interventional implantation of heart valves, the incidence of prosthetic endocarditis is also rising.

METHODS

We summarize the current state of the prophylaxis, diagnosis, and treatment of prosthetic endocarditis in a selective review of the literature.

RESULTS

Prosthetic endocarditis accounts for 10-30% of all cases of endocarditis. As its echocardiographic and microbiologic findings are often less specific than those of native endocarditis, its diagnosis now increasingly relies on alternative imaging modalities such as F-18-FDG PET-CT. Anti-infective and surgical treatment are made more difficult by biofilm formation on the prosthetic valve and the frequent formation of perivalvular abscesses.

CONCLUSION

Increased awareness of this clinical entity in the outpatient setting will promote the earlier initiation of appropriate diagnostic studies. Proper diagnostic evaluation is an essential prerequisite for the early detection and timely treatment of prosthetic endocarditis, with the goal of preventing progressive destruction and thus improving the outcome. Preventive and educative measures should be intensified, and certified, multidisciplinary endocarditis teams should be established. Antibiotic prophylaxis is now given much more restrictively than in earlier years; the risk of infection must be weighed against the potential development of both individual and collective resistance to antibiotic drugs.

Endocarditis in critically ill patients: a review

PURPOSE OF REVIEW

To summarize the advances in literature that support the best current practices regarding infective endocarditis (IE) in critically ill patients.

RECENT FINDINGS

IE due to rheumatic diseases has decreased significantly, and in fact, the majority of cases are associated with degenerative valvopathies, prosthetic valves, and cardiovascular implantable electronic devices. The Duke criteria were recently updated, addressing the increasing incidence of new risk factors for IE, such as IE associated with the use of endovascular cardiac implantable electronic devices and transcatheter implant valves. The presence of organ dysfunction, renal replacement therapies, or extracorporeal membrane oxygenation should be considered in the choice of drug and dosage in critically ill patients with suspected or confirmed IE. As highlighted for other severe infections, monitoring of therapeutic antibiotic levels is a promising technique to improve outcomes in critically ill patients with organ dysfunction.

SUMMARY

The diagnostic investigation of IE must consider the current epidemiological criteria and the diagnostic particularities that these circumstances require. A careful evaluation of these issues is necessary for the prompt clinical or surgical management of this infection.

Commensal Streptococcal Infective Endocarditis of the Native Mitral Valve in a Transcatheter Aortic Valve Replacement (TAVR) Patient: A Heartful, a Handful, and a Mouthful

An 88-year-old woman with an extensive medical history presented to the hospital with altered mental status, vague abdominal pain, and dysuria. A previous transcatheter aortic valve replacement (TAVR) prosthesis was known to be failing and was suspected to have acquired a vegetation. No other infective endocarditis (IE) stigmata were present. Fortunately, the work-up for replacement was allowed to proceed with a broader cardiac examination from which a mitral vegetation was identified and IE then treated.

Microbial Biofilm: A Review on Formation, Infection, Antibiotic Resistance, Control Measures, and Innovative Treatment

Biofilm is complex and consists of bacterial colonies that reside in an exopolysaccharide matrix that attaches to foreign surfaces in a living organism. Biofilm frequently leads to nosocomial, chronic infections in clinical settings. Since the bacteria in the biofilm have developed antibiotic resistance, using antibiotics alone to treat infections brought on by biofilm is ineffective. This review provides a succinct summary of the theories behind the composition of, formation of, and drug-resistant infections attributed to biofilm and cutting-edge curative approaches to counteract and treat biofilm. The high frequency of medical device-induced infections due to biofilm warrants the application of innovative technologies to manage the complexities presented by biofilm.

Infective Endocarditis-Update for the Perioperative Clinician

Infective endocarditis is a common pathology routinely encountered by perioperative physicians. There has been a need for a comprehensive review of this important topic. In this expert review, the authors discuss in detail the incidence, etiology, definition, microbiology, and trends of infective endocarditis. The authors discuss the clinical and imaging criteria for diagnosing infective endocarditis and the perioperative considerations for the same. Other imaging modalities to evaluate infective endocarditis also are discussed. Furthermore, the authors describe in detail the clinical risk scores that are used for determining clinical prognostic criteria and how they are tied to the current societal guidelines. Knowledge about native and prosthetic valve endocarditis, with emphasis on the timing of surgical intervention-focused surgical approaches and analysis of current outcomes, are critical to managing such patients, especially high-risk patients like those with heart failure, patients with intravenous drug abuse, and with internal pacemakers and defibrillators in situ. And lastly, with the advancement of percutaneous transcatheter valves becoming a norm for the management of various valvular pathologies, the authors discuss an in-depth review of transcatheter valve endocarditis with a focus on its incidence, the timing of surgical interventions, outcome data, and management of high-risk patients.

Teicoplanin-Resistant Coagulase-Negative Staphylococci: Do the Current Susceptibility Testing Methods Reliably Detect This Elusive Phenotype?

Coagulase-negative staphylococci (CoNS), members of the skin commensal microbiota, are increasingly associated with local or systemic infections due to a shift in patient populations in recent decades. Subsequently, more CoNS strains have been subjected to antibiotic susceptibility testing (AST), thus leading to the increased detection of teicoplanin resistance. However, data concerning teicoplanin resistance among CoNS strains remain limited, heterogeneous, and inconclusive. We collected 162 consecutive CoNS strains identified using Vitek-2 as teicoplanin-resistant and tested them with a range of AST methods. The results of standard and high inoculum broth microdilution (sBMD; hBMD), agar dilution (AD) after 24 h and 48 h incubation, standard and macrogradient diffusion strip (sGDT, MET), screening agar, and disc diffusion were compared to assess their robustness and to establish a diagnostic algorithm to detect teicoplanin resistance. sBMD was used as the reference method, and the lowest number of strains were teicoplanin-resistant using this method. sGDT and disc diffusion generated similar results to sBMD. Compared with sBMD, AD-24 h generated the lowest number of false teicoplanin-resistant strains, followed by hBMD, AD-48 h, and Vitek-2. sGDT, a fast, easy, affordable method in diagnostic settings, generated the highest rate of false teicoplanin-susceptible strains. Vitek-2 testing produced the highest number of teicoplanin-resistant strains. Only in two strains was the initial Vitek-2 teicoplanin resistance confirmed using five other AST methods. In conclusion, the different antibiotic susceptibility testing methods generated inconsistent, inconclusive, and discrepant results, thus making it difficult to establish a diagnostic algorithm for suspected teicoplanin resistance. Teicoplanin testing proved to be challenging and easily influenced by technical factors. This study aimed not only to raise awareness of teicoplanin resistance testing but also of the need for future studies focusing on the clinical efficacy of teicoplanin in relation to its susceptibility results.

Infective Endocarditis After Transcatheter Aortic Valve Implantation: A Systematic Review

Infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI) is a rare but potentially fatal event. In this systematic review, we searched PubMed and Embase for large TAVI studies and registries to identify the incidence, presentation, microbiology, risk factors, and outcomes of IE in this population. After application of the selection criteria and quality assessment, 8 studies representing 255,310 TAVR cases and 4218 cases of IE qualified for this review. IE following TAVI is uncommon with an incidence of 0.87 to 1.7 events per 100 person-years. Most events occur in the first year following valve implantation. Staphylococcus , Enterococcus , and Streptococcus species are the most common pathogens. Risk factors include age, sex, concomitant comorbidities, and procedural factors. Outcomes are dismal, and surgical intervention is rare in this population.

Towards Longitudinal Monitoring of Leaflet Mobility in Prosthetic Aortic Valves via In-Situ Pressure Sensors: In-Silico Modeling and Analysis

BACKGROUND

Transcatheter aortic valves (TAVs) are susceptible to leaflet thrombosis which may lead to thromboembolic events, and early detection and intervention are believed to be the key to avoiding such adverse outcomes. An embedded sensor system installed on the valve stent, coupled with an appropriate machine learning-based continuous monitoring algorithm can facilitate early detection to predict severity of reduced leaflet motion (RLM) and avoid adverse outcomes.

METHODS

We present a data-driven, in silico, proof-of-concept analysis of a pressure microsensor based system for quantifying RLM in TAVs. We generate a dataset of 21 high-fidelity transvalvular flow simulations with healthy and mildly stenotic TAVs to train a logistic regression model to correlate individual leaflet mobility in each simulation with principal components of corresponding hemodynamic pressure recorded at strategic locations of the TAV stent. A separate test dataset of 7 simulations is also generated for prospective assessment of model performance.

RESULTS

An array of 6 sensors embedded on the TAV stent, with two sensors tracking individual leaflet, successfully correlates leaflet mobility with recorded pressure. The sensors are placed along leaflet centerlines, one in the sinus, and the other at the sino-tubular junction. The regression model is tuned using cross-validation to achieve high accuracy on both training (R² = 0.93) and test (R² = 0.77) sets.

CONCLUSION

Discrete blood pressure recordings on TAV stents can be successfully correlated with individual leaflet mobility. Further development of this technology can enable longitudinal monitoring of TAVs and early detection of valve failure.

Infective Endocarditis After Transcatheter Aortic Valve Replacement: JACC State-of-the-Art Review

Infective endocarditis (IE) is a rare but serious complication following transcatheter aortic valve replacement (TAVR). Despite substantial improvements in the TAVR procedure (less invasive) and its expansion to younger and healthier patients, the incidence of IE after TAVR remains stable, with incidence rates similar to those reported after surgical aortic valve replacement. Although IE after TAVR is recognized as a subtype of prosthetic valve endocarditis, this condition represents a particularly challenging scenario given its unique clinical and microbiological profile, the high incidence of IE-related complications, the uncertain role of cardiac surgery, and the dismal prognosis in most patients with TAVR-IE. The number of TAVR procedures is expected to grow exponentially in the coming years, increasing the number of patients at risk of developing this life-threatening complication. Therefore, a detailed understanding of this disease and its complications will be essential to improve clinical outcomes.

Risk of Infective Endocarditis Associated with Transcatheter Aortic Valve Implantation versus Surgical Aortic Valve Replacement: A Propensity Score-Based Analysis

Background: Infective endocarditis (IE) is a feared complication after surgical aortic valve replacement (SAVR)/transcatheter aortic valve implantation (TAVI). It is not certain which procedure carries a higher risk. Our aim was to assess the risk of IE after SAVR/TAVI. Methods: We conducted an observational study of a prospective cohort, including patients with TAVI/SAVR, from March 2015 to December 2020. IE was defined according to the modified Duke’s criteria. IE occurring during the first 12 months of the procedure was considered early IE, and an episode occurring after 12 months was considered late IE. The propensity score was designed to include variables previously associated with TAVI/SAVR and IE. An inverse probability of treatment weight was generated. Results: In total, 355 SAVR and 278 TAVI were included. Median follow-up, 38 vs. 41 months, p = 0.550. IE occurred in 5 SAVR (1.41%, 95% CI 0.2−2.6) vs. 13 TAVI (4.65%, 95% CI 2.2−7.2), p = 0.016. TAVI patients had more frequent early IE (3.2% vs. 0.3%, p = 0.006). In the PS analyses, IE risk did not differ: OR 0.65, 95% CI 0.32−1.32. Factors associated with TAVI IE included younger age (74y vs. 83y, p = 0.030), complicated diabetes mellitus (38.5% vs. 6.8%, p = 0.002), COPD (46.2% vs. 16.3%, p = 0.015), advanced heart failure (100% vs. 52.9%, p < 0.001), and peripheral arteriopathy (61.5% vs. 26.7%, p = 0.011). Conclusions: Early IE was higher with TAVI, but in the PS analyses, the risk attributable to each procedure was similar. Studies are needed to identify and optimize the risk factors of IE prior to TAVI.

Mitral Valve Endocarditis in Patient Awaiting TAVI: A Case Report

Background

The current literature focuses on the risk of infective endocarditis (IE) following transcatheter aortic valve implantation (TAVI). However, the risk of IE in patients waiting for TAVI is not well-studied. We present a unique case of a patient waiting for TAVI with decompensated heart failure who was found to have a large mitral vegetation, and consider risk factors for the development of IE in this population.

Case description

We report the case of an 85-year-old male with severe aortic stenosis and recurrent small bowel angiodysplasias, requiring frequent blood transfusions and intravenous iron. He presented to a peripheral hospital in decompensated heart failure. Transfer was arranged to our center to expedite TAVI, under the premise that worsening aortic stenosis precipitated his decompensated state. Prior to TAVI, an echocardiogram was done, and demonstrated a 30 × 18 mm mass on the mitral valve with anterior leaflet perforation and severe mitral regurgitation. The findings were consistent with IE, and the TAVI was cancelled. Despite antibiotic therapy, the patient unfortunately deteriorated and palliative care was provided.

Conclusions

This case highlights the need for further research regarding the risk of IE in patients waiting for TAVI. Current literature focuses on the development and management of IE following TAVI. Clinicians must understand that TAVI candidates have multiple risk factors for IE, including valvular disease, age, and comorbidities. IE should be considered as a possible cause for decompensated heart failure in patients awaiting TAVI.

Prosthesis Tailoring for Patients Undergoing Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) has risen over the past 20 years as a safe and effective alternative to surgical aortic valve replacement for treatment of severe aortic stenosis, and is now a well-established and recommended treatment option in suitable patients irrespective of predicted risk of mortality after surgery. Studies of numerous devices, either newly developed or reiterations of previous prostheses, have been accruing. We hereby review TAVI devices, with a focus on commercially available options, and aim to present a guide for prosthesis tailoring according to patient-related anatomical and clinical factors that may favor particular designs.

Subsequent cardiac surgery after transcatheter aortic valve implantation: Indications and outcomes

BACKGROUND

Aim of this study was to report on indications and clinical outcomes of patients who underwent subsequent open-cardiac surgery after transcatheter aortic valve implantation TAVI.

METHODS

Between 01/2011 and 12/2020 our centre performed 4043 TAVI procedures. Twenty-seven patients (including patients in whom TAVI was performed in other centres) underwent subsequent open-heart surgery via cardiopulmonary bypass. Demographic, intraprocedural data, indications for, and outcomes after surgery were evaluated.

RESULTS

Indications for cardiac surgery (aged 79 [IQR 76-84]; 59.3% male) were endocarditis (n = 11; 40.7%), annular rupture, severe paravalvular leak and severe stenosis in three (11.1%) patients, respectively as well as in one patient each (3.7%) severe tricuspid valve regurgitation, valve thrombosis, valve malposition, valve migration, ostial right coronary artery obstruction, left ventricular rupture and type A aortic dissection. The interval between the index TAVI procedure to open surgery was 3 months (IQR 0-26 months). Eight patients underwent emergent surgical conversions. Immediate procedural and procedural mortality was 25.9% and 40.7%, respectively and all-cause mortality was 51.9% (11/12 died for cardiovascular reasons). No disabling stroke was observed postoperatively. New permanent pacemaker implantation was required in three patients (11.1%).

CONCLUSIONS

Subsequent open-cardiac surgery after TAVI is rare, but may urgently become necessary due to TAVI related complications or progressing other cardiac pathologies. Despite a substantial early attrition rate clinical outcome is acceptable and a relevant number of these high-risk patients can be discharged even after emergency conversions. The option of subsequent surgical conversion remains.

Three-dimensional printing in integrated multi-modality imaging approach for management of prosthetic valves infective endocarditis

After heart failure, infectious endocarditis is the second leading cause of death in patients with prosthetic valves. Aortic pseudoaneurysms are a serious complication of infective endocarditis in mechanical or bioprosthetic aortic prostheses. Diagnostic and management challenges are posed by aortic pseudoaneurysms. In these cases, a multi-modality imaging approach with a heart team is recommended. We described two cases of aortic pseudoaneurysms that developed as a result of infective endocarditis. The first case involved a TAVI patient who developed infective endocarditis as a result of diabetic foot complications. Because traditional echocardiography and computed tomography failed to show the anatomy of the lesion, we used 3D printing to show the anatomy, extension of the pseudoaneurysm, and proximity to the right coronary artery. The second case involved a patient who underwent Bentall's surgery with an aortic root and mechanical aortic valve and later developed infective endocarditis complicated by pseudoaneurysms. In this case, 3D printing was used for preoperative surgical planning.

Macroscopic and microscopic features of surgically explanted transcatheter aortic valve prostheses

OBJECTIVES

With the extended indications of transcatheter aortic valve (TAV) replacement (TAVR) to lower-risk patients, there is an increasing number of patients requiring surgical explantation of failed TAV. We sought to describe macroscopic and microscopic features of surgically explanted percutaneous aortic valve prostheses.

METHODS

Preoperative and surgical characteristic of patients undergoing surgical explantation of TAV were retrospectively analyzed from 2007 to 2020. Surgical and pathologic features of these valves, and outcomes of the surgical valve replacement were described.

RESULTS

Out of 1764 patients who underwent a TAVR procedure, 21 were operated for TAV failure. Isolated or combined indications for surgery included: significant paravalvular leak (n = 15), delayed prosthesis migration (n = 5), significant increase of trans-TAV gradients (n = 6), and endocarditis (n = 3). Mean time elapsed between TAVR and explantations was 674.9 ± 803.9 days. Macroscopic lesions found on explanted percutaneous valves were severe adhesions to the aorta (n = 10), calcifications (n = 7), leaflet thrombosis (n = 4), and vegetations (n = 3). Except for patients with endocarditis, one or more pathological lesions were found in 15 patients. Pathology analyses on these valves showed fibro-calcific degenerations (n = 12), pannus formation (n = 9), and chronic inflammation (n = 3). One patient (4.8%) died after surgical explantation, and 13 (61.9%) had concomitant procedures. The survival rate at 1 year was 94.4%.

CONCLUSIONS

Microscopic findings of fibro-calcific leaflet degeneration, and pannus formation in addition to macroscopic calcification and thrombosis present early, (within a mean of 2 years) after TAVR. Further investigation with a higher number of patients and echocardiographic follow-up is warranted.

FDG PET/CT in Cardiac Infection: Does It Matter? A Narrative Review

The limited performance of echocardiography in specific infectious processes involving the heart led to the search for additional diagnostic tools. Fluorodeoxyglucose positron emission tomography computed tomography (FDG PET/CT) has been proposed for its diagnostic abilities in several infectious diseases including cardiac infections. A literature review of studies evaluating FDG PET/CT in native valve infective endocarditis (IE), prosthetic valve IE, cardiac implantable electrical device (CIED) infection, and left ventricular assist device (LVAD) infection is presented, focusing on studies published in recent years. Overall, in prosthetic valve endocarditis (PVE), FDG PET/CT demonstrate high sensitivity (73-93%) and specificity (80-95%), while in native valve endocarditis (NVE) the sensitivity is very low (22-68%), with high specificity (97-100%) similar to PVE. For CIED, LVAD infection, and transcatheter aortic valve implantation associated endocarditis, data come from small studies and show good diagnostic performance of FDG PET/CT. International guidelines are increasingly recommending FDG PET/CT for the diagnosis of specific conditions of cardiac infections. Beyond the diagnostic performance ability, few studies have evaluated the added benefit of FDG PET/CT in terms of clinical outcomes of patients with suspected cardiac infection. This should be the focus in future studies.

Surgical explantation of failed transcatheter heart valves: indications and results

Given the recent surge in transcatheter heart valve replacement (THVR), cardiac surgeons will surely face the challenge of eventual explantation. The aim of this study was to determine indications for reoperation, while exploring pertinent technical aspects and survival after THV explantation in a cohort originally deemed high risk or even inoperable. Between February 2008 and March 2019, 31 patients with failed transcatheter aortic valve replacement (TAVR) underwent surgical explantations at our facility. Data were prospectively collected for retrospective analysis of procedural indications, technical issues, and postoperative survival. The major reason for TAVR removal was bioprosthetic valve failure (BVF) due to infective endocarditis (IE: 16/31 [51.6%]), non-structural (NSVD: 14/31 [45.2%]) and structural (SVD: 1/31 [3.2%]) valve deterioration accounting for the rest. Mean age at THV explantation was 76.3 ± 8.3 years, and median time from TAVR to explantation was 153 days (0 days-56.6 months). Median ICU and hospital stay were 6 days (1-44 days) and 23 days (8-62 days), respectively. Thirty-day and 1-year survival rates were 74.2% and 67.2%, respectively. Median follow-up interval after explantation was 364 days (3 days-80 months). Mean cardiopulmonary bypass time was 124.6 ± 46.8 min, and mean aortic cross-clamp time was 84.3 ± 32.9 min. There was no need for unplanned aortic root repair owing to tissue damage during dissection of the TAVR from surrounding tissue. The most common reason for THV explantation was (a) BVF for IE and (b) BVF secondary to NSVD. Although 30-day and 1-year mortality rates in this multimorbid cohort were predictably high, no procedural mortalities occurred.

Infective Endocarditis in the Elderly: Challenges and Strategies

The specific management of infective endocarditis (IE) in elderly patients is not specifically addressed in recent guidelines despite its increasing incidence and high mortality in this population. The term "elderly" corresponds to different ages in the literature, but it is defined by considerable comorbidity and heterogeneity. Cancer incidence, specifically colorectal cancer, is increased in older patients with IE and impacts its outcome. Diagnosis of IE in elderly patients is challenging due to the atypical presentation of the disease and the lower performance of imaging studies. Enterococcal etiology is more frequent than in younger patients. Antibiotic treatment should prioritize diminishing adverse effects and drug interactions while maintaining the best efficacy, as surgical treatment is less commonly performed in this population due to the high surgical risk. The global assessment of elderly patients with IE, with particular attention to frailty and geriatric profiles, should be performed by multidisciplinary teams to improve disease management in this population.

Mitral Valve Infective Endocarditis after Trans-Catheter Aortic Valve Implantation

Scarce data exist on mitral valve (MV) infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI). This multicenter study included a total of 579 patients with a diagnosis of definite IE after TAVI from the IE after TAVI International Registry and aimed to evaluate the incidence, characteristics, management, and outcomes of MV-IE after TAVI. A total of 86 patients (14.9%) had MV-IE. These patients were compared with 284 patients (49.1%) with involvement of the transcatheter heart valve (THV) only. Two factors were found to be associated with MV-IE: the use of self-expanding valves (adjusted odds ratio 2.49, 95% confidence interval [CI] 1.23 to 5.07, p = 0.012), and the presence of an aortic regurgitation ≥2 at discharge (adjusted odds ratio 3.33; 95% CI 1.43 to 7.73, p <0.01). There were no differences in IE timing and causative microorganisms between groups, but surgical management was significantly lower in patients with MV-IE (6.0%, vs 21.6% in patients with THV-IE, p = 0.001). All-cause mortality rates at 2-year follow-up were high and similar between patients with MV-IE (51.4%, 95% CI 39.8 to 64.1) and patients with THV-IE (51.5%, 95% CI 45.4 to 58.0) (log-rank p = 0.295). The factors independently associated with increased mortality risk in patients with MV-IE were the occurrence of heart failure (adjusted p <0.001) and septic shock (adjusted p <0.01) during the index hospitalization. One of 6 IE episodes after TAVI is localized on the MV. The implantation of a self-expanding THV and the presence of an aortic regurgitation ≥2 at discharge were associated with MV-IE. Patients with MV-IE were rarely operated on and had a poor prognosis at 2-year follow-up.

Infective Endocarditis Complicated With Septic Embolic Stroke After Transcatheter Aortic Valve Implantation: A Case Report

Transcatheter aortic valve implantation (TAVI) is a relatively novel procedure developed for aortic stenosis (AS) management in patients with moderate to high surgical risk, especially the elderly with multiple comorbidities. Infective endocarditis following transcatheter aortic valve implantation (post-TAVI-IE) is an uncommon complication that contributes to very high morbidity and mortality. Further complications from post-TAVI-IE include ischemic stroke from septic emboli. Here, we report a case of an 82-year-old man with severe symptomatic AS who underwent TAVI, presenting with fever and alteration of consciousness, which was diagnosed as post-TAVI-IE per Duke criteria complicated by acute hemiparesis from septic emboli stroke. He was treated successfully conservatively using antibiotics. We have reviewed the options of treatment and outcomes for post-TAVI-IE.

Cardiac surgery in patients with cardiac implantable electronic devices and risk of device infections: a nationwide nested case–control study

PURPOSE

Cardiac surgery in patients with cardiac implantable electronic devices (CIEDs) has been associated with a higher risk of infective endocarditis, but how it influences risk of CIED-specific infections is not known. Our aim was to examine risk of systemic CIED infections after cardiac surgery in patients with CIEDs.

METHODS

Based on data obtained from Danish administrative registries and the Danish Pacemaker and ICD Register, we conducted a case-control study nested within a nationwide cohort of patients who underwent a de novo CIED implantation in Denmark between 1998 and 2017. We defined cases as incident systemic CIED infections resulting in device system extraction. Controls were sampled 1:100 on time, age, sex and device type using risk set sampling. Exposure was defined as coronary artery bypass graft, or cardiac heart valve replacement or repair surgery.

RESULTS

From a study cohort comprising 67,621 patients, we identified 170 cases and 16,788 controls. In the minimally adjusted model, the incidence rate ratio (IRR) for systemic CIED infection was 6.4 (95% confidence interval (CI) 3.8-10.7) with cardiac surgery, and after additional confounder adjustment, 5.4 (95% CI 3.2-9.2). IRRs were higher with restriction to heart valve replacement surgery (adjusted IRR 7.5, 95% CI 4.0-16.6), and when limiting our exposure time window to one year (adjusted IRR 10.1, 95% CI 4.5-22.3).

CONCLUSION

Cardiac surgery in patients with de novo CIEDs was associated with a high risk of systemic CIED infections. Highest risk was observed after heart valve replacement surgery and within the first year of surgery.

Nomogram for Predicting In-hospital Mortality in Infective Endocarditis Based on Early Clinical Features and Treatment Options

Aim

The aim of this study was to develop a nomogram based on early clinical features and treatment options for predicting in-hospital mortality in infective endocarditis (IE).

Methods

We retrospectively analyzed the data of 294 patients diagnosed with IE in our hospital from June 01, 2012 to November 24, 2021, determined independent risk factors for in-hospital mortality by univariate and multivariate logistic regression analysis, and established a Nomogram prediction model based on these factors. Finally, the prediction performance of nomogram is evaluated by C-index, bootstrapped-concordance index, and calibration plots.

Results

Age, abnormal leukocyte count, left-sided IE, right-sided IE, and no surgical treatment were independent risk factors for in-hospital mortality in patients with IE, and we used these independent risk factors to construct a nomogram prediction model to predict in-hospital mortality in IE. The C-index of the model was 0.878 (95% CI: 0.824–0.931), and the internal validation of the model by bootstrap validation method showed a prediction accuracy of 0.852 and a bootstrapped-concordance index of 0.53.

Conclusion

Our nomogram can accurately predict in-hospital mortality in IE patients and can be used for early identification of high-risk IE patients.

Cardiac Imaging for Diagnosis and Management of Infective Endocarditis

Imaging is central to the care of patients with infective endocarditis. While transthoracic and transesophageal echocardiography are the principle imaging techniques, additional modalities including positron emission tomography and cardiac computed tomography, and to a lesser extent intracardiac echocardiography, play an increasing role. This review discusses the role of cardiac imaging in establishing the diagnosis of endocarditis, in predicting its embolic risk and in making decisions regarding the need for and timing of surgery.

Transcatheter Aortic Valve Replacement-Associated Infective Endocarditis: Comparison of Early, Intermediate, and Late-Onset Cases

Background

Transcatheter aortic valve replacement-associated infective endocarditis (TAVR-IE) is a relatively rare complication of TAVR. Little is known about the characteristics of early, intermediate, and late-onset TAVR-IE.

Methods

We studied the risk factors, microbiological patterns, and diagnostic and treatment strategies in patients with early (<60 days), intermediate (60-365 days), and late-onset (>1 year) TAVR-IE.

Results

Ten out of 494 definite cases of prosthetic valve IE between 2007 and 2019 were confirmed to have TAVR-IE from the IE registry at our center. The mean age was 78.1 ± 13.7 years, with 50% being female. The mean Society of Thoracic Surgeons risk score was 7.8 ± 5.7. Most (60%) TAVR-IE cases had an intermediate onset, with Staphylococcus aureus being the most common organism (66.6%). 18-fluorodeoxyglucose positron emission tomography aided in diagnosis of TAVR-IE in 20% of cases. Mortality due to IE was observed in 40% of cases. Most of the patients underwent conservative management, and 37.5% survived over a mean follow-up of 709 ± 453 days. Two patients underwent surgery, of whom one died on day 30 postoperatively from sepsis. Mortality due to IE occurred in 25% of cases in the early and intermediate-onset groups, while there was 100% mortality in the late-onset group.

Conclusions

In a single-center cohort, most TAVR-IE cases had an intermediate onset, with Staphylococcus aureus being the most common organism. Understanding timing of TAVR-IE may have important prognostic implications.

Introduction of the Rapid Deployment Aortic Valve System Use in Elderly Patients With Endocarditis

Introduction

The rapid-deployment valve system (RDVS) was introduced to facility minimally invasive aortic valve replacement. In this study we evaluate the potential benefits of RDVS in elderly high-risk patients with endocarditis of the aortic valve.

Materials and Methods

Since the introduction of RDVS in our institution in December 2017 through October 2021, EDWARDS INTUITY rapid-deployment prosthesis (Model 8300A, Edwards Lifesciences, Irvine, CA, USA) has been implanted in a total of 115 patients for different indications by a single surgeon. Out of one-hundred and fifteen cases of RDVS implantation, seven patients with a median age of 77 yrs. (range 62-84yrs.), suffered from active infective endocarditis of the aortic valve. The median EuroSCORE II of these highly selected patient cohort was 77% (range 19-80%). Patient data were evaluated perioperatively including intra-operative data as well as in-hospital morbidity/mortality and follow-up after discharge from hospital.

Results

Three patients underwent previous cardiac surgery. Concomitant procedures were performed in six patients including, ascending aorta replacement (n = 3), mitral valve repair (n = 1), pulmonary valve replacement (n = 1), bypass surgery (n = 1), left atrial appendix resection (n = 1) and anterior mitral valve repair (n = 1). Median aortic cross-clamp and cardiopulmonary bypass time was 56 min (range 29-122 min) and 81 min (range 45-162 min.), respectively. Post-operative complications in these elderly high-risk patients were atrial fibrillation (n = 3) and re-exploration for pericardial effusion (n = 1). One pacemaker implantation was required on postoperative day 6 due to sick sinus syndrome. There was one in-hospital death (14%) and one during follow-up (14%).

Conclusion

Rapid-deployment aortic valve system seems to be a viable option with acceptable morbidity and mortality in elderly high-risk patients with active infective endocarditis of the aortic valve.

Surgical Treatment of Patients With Infective Endocarditis After Transcatheter Aortic Valve Implantation

BACKGROUND

The optimal treatment of patients developing infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI) is uncertain.

OBJECTIVES

The goal of this study was to investigate the clinical characteristics and outcomes of patients with TAVI-IE treated with cardiac surgery and antibiotics (IE-CS) compared with patients treated with antibiotics alone (IE-AB).

METHODS

Crude and inverse probability of treatment weighting analyses were applied for the treatment effect of cardiac surgery vs medical therapy on 1-year all-cause mortality in patients with definite TAVI-IE. The study used data from the Infectious Endocarditis after TAVI International Registry.

RESULTS

Among 584 patients, 111 patients (19%) were treated with IE-CS and 473 patients (81%) with IE-AB. Compared with IE-AB, IE-CS was not associated with a lower in-hospital mortality (HR_unadj: 0.85; 95% CI: 0.58-1.25) and 1-year all-cause mortality (HR_unadj: 0.88; 95% CI: 0.64-1.22) in the crude cohort. After adjusting for selection and immortal time bias, IE-CS compared with IE-AB was also not associated with lower mortality rates for in-hospital mortality (HR_adj: 0.92; 95% CI: 0.80-1.05) and 1-year all-cause mortality (HR_adj: 0.95; 95% CI: 0.84-1.07). Results remained similar when patients with and without TAVI prosthesis involvement were analyzed separately. Predictors for in-hospital and 1-year all-cause mortality included logistic EuroSCORE I, Staphylococcus aureus, acute renal failure, persistent bacteremia, and septic shock.

CONCLUSIONS

In this registry, the majority of patients with TAVI-IE were treated with antibiotics alone. Cardiac surgery was not associated with an improved all-cause in-hospital or 1-year mortality. The high mortality of patients with TAVI-IE was strongly linked to patients' characteristics, pathogen, and IE-related complications.

Infective Endocarditis: New Challenges in a Classic Disease

Infective endocarditis is a relatively rare, but deadly infection, with an overall mortality of around 20% in most series. Clinical manifestations have evolved in response to significant epidemiological shifts in industrialized nations, with a move toward a nosocomial or health-care-related pattern, in older patients, with more episodes associated with prostheses and/or intravascular electronic devices and a predominance of staphylococcal and enterococcal etiology.Diagnosis is often challenging and is based on the conjunction of clinical, microbiological, and imaging information, with notable progress in recent years in the accuracy of echocardiographic data, coupled with the recent emergence of other useful imaging techniques such as cardiac computed tomography (CT) and nuclear medicine tools, particularly ¹⁸F-fluorodeoxyglucose positron emission/CT.The choice of an appropriate treatment for each specific case is complex, both in terms of the selection of the appropriate agent and doses and durations of therapy as well as the possibility of using combined bactericidal antibiotic regimens in the initial phase and finalizing treatment at home in patients with good evolution with outpatient oral or parenteral antimicrobial therapies programs. A relevant proportion of patients will also require valve surgery during the active phase of treatment, the timing of which is extremely difficult to define. For all the above, the management of infective endocarditis requires a close collaboration of multidisciplinary endocarditis teams.

Epidemiology of infective endocarditis: novel aspects in the twenty-first century

INTRODUCTION

The epidemiology of infective endocarditis (IE) in this millennium has changed with emergence of new risk factors and reemergence of others. This, coupled with modifications in national guidelines in the setting of a pandemic, prompted an address of the topic.

AREAS COVERED

Our goal is to provide a contemporary review of IE epidemiology considering changing incidence of rheumatic heart disease (RHD), cardiac device implantation, and injection drug use (IDU), with SARS-CoV-2 pandemic as the backdrop.

METHODS

PubMed and Google Scholar were used to identify studies of interest.

EXPERT OPINION

Our experience over the past two decades verifies the notion that there is not one 'textbook' profile of IE. Multiple factors have dramatically impacted IE epidemiology, and these factors differ, based, in part on geography. RHD has declined in many areas of the world, whereas implanted cardiovascular devices-related IE has grown exponentially. Perhaps the most influential, at least in areas of the United States, is injection drug use complicating the opioid epidemic. Healthy younger individuals contracting a potentially life-threatening infection has been tragic. In the past year, epidemiological changes due to the COVID-19 pandemic have also occurred. No doubt, changes will characterize IE in the future and serial review of the topic is warranted.

Risk of infective endocarditis after surgical and transcatheter aortic valve replacement

Objective

To define the incidence and risk factors for infective endocarditis (IE) following surgical aortic valve replacement (SAVR) and transcatheter aortic valve implantation (TAVI).

Methods

All patients who underwent first SAVR or TAVI in England between 2007 and 2016 were identified from the NICOR databases. Hospital admissions with a primary diagnosis of IE were identified by linkage with the NHS Hospital Episode Statistics database. Approval was obtained from the NHS Research Ethics Committee.

Results

2057 of 91 962 patients undergoing SAVR developed IE over a median follow-up of 53.9 months—an overall incidence of 4.81 [95% CI 4.61 to 5.03] per 1000 person-years. Correspondingly, 140 of 14 195 patients undergoing TAVI developed IE over a median follow-up of 24.5 months—an overall incidence of 3.57 [95% CI 3.00 to 4.21] per 1000 person-years. The cumulative incidence of IE at 60 months was higher after SAVR than after TAVI (2.4% [95% CI 2.3 to 2.5] vs 1.5% [95% CI 1.3 to 1.8], HR 1.60, p<0.001). Across the entire cohort, SAVR remained an independent predictor of IE after multivariable adjustment. Risk factors for IE included younger age, male sex, atrial fibrillation, and dialysis.

Conclusions

IE is a rare complication of SAVR and TAVI. In our population, the incidence of IE was higher after SAVR than after TAVI.

Surgery after Failed Transcatheter Aortic Valve Implantation: Indications and Outcomes of a Concerning Condition

OBJECTIVES

The number of transcatheter aortic valve implantations (TAVI) has increased enormously in recent decades. Transcatheter valve prosthesis failure and the requirement of conventional surgical replacement are expected to attract more focus in the near future. Indeed, given the scarcity of research in this field, the next decade will likely represent the beginning of a period of meaningful exploration of the degenerative changes that occur with transcatheter valves. The current study represents-through a series of consecutive cases-one of the first analyses of the underlying causes of TAVI failure, i.e., degenerative, functional and infective, followed by surgical aortic valve replacement (SAVR) and postoperative outcome.

METHODS

Between October 2008 and March 2021, 2098 TAVI procedures, including 1423 with transfemoral, 309 with transapical, and 366 with transaortic access, were performed in our institution. Among these, 0.5% (number(n) = 11) required acute SAVR (n = 6) within 7 days (n = 3) or later (n = 2), and were included in the study.

RESULTS

Valve stent dislocation was the most common cause of replacement (83%). Causes of replacement within 7 days after TAVI were multifactorial. In the later course, endocarditis was the sole indication for SAVR after TAVI. TAVI with transapical or transaortal approach had a higher EuroSCORE II (10.9 (7.2-35.3) vs. 3.5 (1.8-7.8)). Their 30-day mortality after surgical conversion was higher (67% vs. 20%), when compared to those who underwent a transfemoral procedure. The longest documented survival beyond 30 days was 58 months.

CONCLUSIONS

The causes of SAVR after TAVI failure are multifactorial, and include biological, physical and infectious factors. An acceptable midterm prognosis may be expected in patients with physical causes when dislocation of the catheter prosthesis is observed; in such cases, emergency conversion is required. Conversion due to infection, as in cases of endocarditis, had the worst outcome. Prognosis after conversion due to degeneration is still problematic, due to a lack of autopsies and the recent history of prosthetic implantations.

Transcatheter aortic valve replacement associated infective endocarditis case series: broadening the criteria for diagnosis is the need of the hour

Background

Transcatheter valve replacement (TAVR) is an important therapeutic intervention for patients with aortic valve stenosis. As TAVR has become available to a broader population, there has been an increase in the number of less common, yet potentially catastrophic, complications. TAVR related infective endocarditis (TAVR-IE) is a rare, but potentially fatal, complication.

Case series

We present here two patients that we encountered for TAVR associated infective endocarditis. Our first patient presented 5 weeks after his TAVR. His initial presentation was consistent with signs of sepsis. The patient then developed Mobitz type I block during hospital course. His TEE was negative for features of infective endocarditis. Due to high suspicion, patient was taken for surgical exploration and was found to have multiple foci of vegetation adhered to the stent frame. Our second patient presented with new onset pulmonary edema, worsening heart failure and systemic inflammatory response. A TEE was done for persistent MSSA bacteremia which showed stable prosthetic valve function with no signs of infective endocarditis. Patient was discharged with a prolonged course of intravenous antibiotics. Patient was re-admitted for worsening sepsis and blood cultures were positive for MSSA. Patient was taken for surgical exploration of his prosthetic aortic valve which showed purulent aortic root abscess.

Conclusion

Through these cases, we aim to raise awareness on TAVR-IE. Due to the atypical clinical presentation, the modified Duke criteria may not be sufficient to diagnose TAVR-IE. Transesophageal echocardiogram in TAVR-IE may be negative or indeterminate. Prosthetic valve shadow may obscure smaller vegetations and/or smaller abscesses. A negative transesophageal echocardiogram should not rule out TAVR-IE and further diagnostic imaging modalities should be considered. PET/CT after administration of 18F-FDG (fluorodeoxyglucose) is a useful diagnostic tool in the diagnosis of infective endocarditis where TEE has been negative or inconclusive. Multi-modal imaging, in addition to the modified Duke criteria, can facilitate early diagnosis and improved mortality outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02364-0.

Detecting Aortic Valve Anomaly From Induced Murmurs: Insights From Computational Hemodynamic Models

Patients who receive transcatheter aortic valve replacement are at risk for leaflet thrombosis-related complications, and can benefit from continuous, longitudinal monitoring of the prosthesis. Conventional angiography modalities are expensive, hospital-centric and either invasive or employ potentially nephrotoxic contrast agents, which preclude their routine use. Heart sounds have been long recognized to contain valuable information about individual valve function, but the skill of auscultation is in decline due to its heavy reliance on the physician's proficiency leading to poor diagnostic repeatability. This subjectivity in diagnosis can be alleviated using machine learning techniques for anomaly detection. We present a computational and data-driven proof-of-concept analysis of a novel, auscultation-based technique for monitoring aortic valve, which is practical, non-invasive, and non-toxic. However, the underlying mechanisms leading to physiological and pathological heart sounds are not well-understood, which hinders development of such a technique. We first address this by performing direct numerical simulations of the complex interactions between turbulent blood flow in a canonical ascending aorta model and dynamic valve motion in 29 cases with healthy and stenotic valves. Using the turbulent pressure fluctuations on the aorta lumen boundary, we model the propagation of heart sounds, as elastic waves, through the patient's thorax. The heart sound may be recorded on the epidermal surface using a stethoscope/phonocardiograph. This approach allows us to correlate instantaneous hemodynamic phenomena and valve motion with the acoustic response. From this dataset we extract "acoustic signatures" of healthy and stenotic valves based on principal components of the recorded sound. These signatures are used to train a linear discriminant classifier by maximizing correlation between recorded heart sounds and valve status. We demonstrate that this classifier is capable of accurate prospective detection of anomalous valve function and that the principal component-based signatures capture prominent audible features of heart sounds, which have been historically used by physicians for diagnosis. Further development of such technology can enable inexpensive, safe and patient-centric at-home monitoring, and can extend beyond transcatheter valves to surgical as well as native valves.

Ampicillin Plus Ceftriaxone Regimen against Enterococcus faecalis Endocarditis: A Literature Review

Enterococcus faecalis infective endocarditis (EFIE) continues to represent a potentially fatal infectious disease characterized by elevated morbidity and mortality. Despite advances in antimicrobial therapy, changing demographics and the reduced availability of useful antibiotics combined with the dissemination of multi-drug resistant strains, the mortality rate remained unchanged in the last decades. Nowadays, optimizing the antibiotic regimen is still of paramount importance. Historically, aminoglycosides were considered as a cornerstone for treatment even though their use is associated with a high risk of kidney failure. It is against this background that, in recent years, several studies have been carried in order to assess the validity of alternative therapeutic approaches, including combinations of beta-lactams, that, acting synergistically, have yielded useful results in different clinical settings. In this scenario, we searched and critically report clinical studies assessing the efficacy and safety of double beta-lactam therapy in treating EFIE.

Incidence and Outcomes of Infective Endocarditis After Transcatheter or Surgical Aortic Valve Replacement

Background

Data comparing the frequency and outcomes of infective endocarditis (IE) after transcatheter (TAVR) to surgical aortic valve replacement (SAVR) are scarce. The objective of this study is to compare the incidence and outcomes of IE after TAVR using a supra‐annular, self‐expanding platform (CoreValve and Evolut) to SAVR.

Methods and Results

Data of 3 randomized clinical trials comparing TAVR to SAVR and a prospective continued TAVR access study were pooled. IE was defined on the basis of the modified Duke criteria. The cumulative incidence of IE was determined by modeling the cause‐specific hazard. Estimates of all‐cause mortality were calculated by means of the Kaplan–Meier method. Outcomes are reported for the valve‐implant cohort. During a mean follow‐up time of 2.17±1.51 years, 12 (0.5%) of 2249 patients undergoing TAVR and 21 (1.1%) of 1828 patients undergoing SAVR developed IE. Patients with IE more frequently had diabetes mellitus than those without (57.6% versus 34.2%; P=0.005). The cumulative incidence of IE was 1.01% (95% CI, 0.47%–1.96%) after TAVR and 1.58% (95% CI, 0.97%–2.46%) after SAVR (P=0.047) at 5 years. Among patients with IE, the rate of all‐cause mortality was 27.3% (95% CI, 1.0%–53.6%) in the TAVR and 51.8% (95% CI, 28.2%–75.3%) in the SAVR group at 1 year (log‐rank P=0.15).

Conclusions

Pooled prospectively collected data comparing TAVR with a supra‐annular, self‐expanding device to SAVR showed a low cumulative risk of IE irrespective of treatment modality, although the risk was lower in the TAVR implant group. Once IE occurred, mortality was high.

Registration

URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01240902, NCT01586910, NCT02701283.

Multimodality imaging in the diagnosis and management of prosthetic valve endocarditis: A contemporary narrative review

Infective endocarditis is one of the leading life-threatening infections around the world. With the exponential growth in the field of transcatheter interventions and advances in specialized surgical techniques, the number of prosthetic valves and cardiac implantable devices has significantly increased. This has led to a steep rise in the number of cases of prosthetic valve endocarditis (PVE) comprising up to 30% of all cases. Clinical guidelines rely on the use of the modified Duke criteria; however, the diagnostic sensitivity of the modified Duke criteria is reduced in the context of PVE. This is in part attributed to prosthesis related artifact which greatly affects the ability of echocardiography to detect early infective changes related to PVE in certain cases. There has been increasing recognition of the roles of complementary imaging modalities and updates in international society recommendations. Prompt diagnosis and treatment can prevent the devastating consequences of this condition. Imaging modalities such as cardiac computed tomography and ¹⁸-fluorodeoxyglucose positron emission tomography/computed tomography are diagnostic tools that provide a complementary role to echocardiography in aiding diagnosis, pre-operative planning, and treatment decision-making process in these challenging cases. Understanding the strengths and limitations of these adjuvant imaging modalities is crucial for the implementation of appropriate imaging modalities in clinical practice.