Do all patients with prosthetic valve endocarditis need surgery?

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.

Case report: Fatal systemic embolism caused by early prosthetic valve endocarditis after Bentall surgery

Prosthetic valve endocarditis (PVE) is a rare but dangerous complication of Bentall surgery and Staphylococcus epidermidis PVE involving multiple valves simultaneously during the early postoperative period has not been reported. A 42 year old patient admitted to intensive care unit with fever 1 month after aortic valve replacement (Bentall procedure). Echocardiography was of great diagnosis value and suggested large, mobile vegetations on both the prosthetic aortic valve and native tricuspid valve. The presence of Staphylococcus epidermidis was revealed by multiple blood cultures. Surgery was not performed because of the history of aortic valve replacement 1 month ago. He developed acute right femoral artery thromboembolism, multiple cerebral infarction and splenic infarction during hospitalization and died of cerebral infarction after being discharged. This case underlines that patients with early PVE may have poor prognosis and fatal systemic embolism should be aware of in PVE patients with large vegetations present with dyskinesia, abdominal pain, and limb numbness. The timely echocardiography and vascular ultrasound are primary and reliable diagnostic methods in this scenario.

Recurrent Multivalvular Staphylococcus Lugdunensis Endocarditis Causing Complete Heart Block after TAVR

Prosthetic valve endocarditis after transcatheter aortic valve replacement (PVE after TAVR) is a feared complication most often observed during the early postprocedural period. We report a case of severe, multivalvular PVE after TAVR with complete heart block caused by an uncommon organism. A 78-year-old female with prior Streptococcus agalactiae mitral valve endocarditis treated with antibiotics presented one year later with severe, symptomatic aortic insufficiency. She subsequently underwent TAVR given high surgical risk. Six weeks post-TAVR, she presented with syncope, fever, and complete heart block. Transthoracic echocardiogram was not demonstrative of vegetation. Blood cultures were positive for Staphylococcus lugdunensis. Transesophageal echocardiogram (TEE) demonstrated vegetations of the aortic, mitral, and tricuspid valves and aorto-mitral continuity. While awaiting surgery, the patient developed cardiac arrest; she was resuscitated and taken to surgery emergently. The patient underwent TAVR explantation, bovine pericardial tissue aortic and porcine bioprosthetic mitral valve replacements, and tricuspid valve repair. Additionally, left main coronary artery endarterectomy was performed due to presence of infectious vegetative material. Staphylococcus lugdunensis is an unusual but virulent organism that may damage both native and prosthetic valves. Early surgery is recommended for PVE after TAVR, especially in cases with perivalvular disease causing conduction abnormalities. Learning Objectives. TAVR has revolutionized the management of severe aortic stenosis and has even been successfully utilized in select cases of aortic regurgitation. Unfortunately, there are a number of associated complications that can be difficult to diagnose, such as prosthetic valve endocarditis (PVE). We emphasize maintaining a high clinical suspicion for PVE after TAVR in patients presenting with conduction abnormalities and highlight the importance of early surgical management in cases complicated by heart block, abscesses, or destructive penetrating lesions.

2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

This executive summary of the valvular heart disease guideline provides recommendations for clinicians to diagnose and manage valvular heart disease as well as supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from January 1, 2010, to March 1, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, Cochrane, Agency for Healthcare Research and Quality Reports, and other selected database relevant to this guideline. Structure: Many recommendations from the earlier valvular heart disease guidelines have been updated with new evidence and provides newer options for diagnosis and treatment of valvular heart disease. This summary includes only the recommendations from the full guideline which focus on diagnostic work-up, the timing and choice of surgical and catheter interventions, and recommendations for medical therapy. The reader is referred to the full guideline for graphical flow charts, text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in developing these guidelines.

A narrative review of early surgery versus conventional treatment for infective endocarditis: do we have an answer?

The most appropriate strategy and timing for surgery in infective endocarditis (IE) remains an argument of debate. Despite some authors promote the adoption of an early surgical approach (within 48 hours) to limit mortality and complications, no robust randomized trials are available on this argument and the evidence on this subject remain at the "expert opinion" level. Additionally, the different messages promulgated by the American and European guidelines contributed to fuel confusion regarding the relative priority of the surgical over medical therapy in IE. The European Society of Cardiology (ESC) guidelines individuates three level of urgency: emergency surgery, to be performed within 24 hours; urgent surgery, recommended within a few days; elective surgery to be performed after 1-2 weeks of antibiotic therapy. Urgent surgery is recommended for most cases of IE. In the American Heart Association (AHA)'s guidelines define early surgery as "during the initial hospitalization and before completion of a full course of antibiotics." Some of the available evidences showed that are no proven benefits in delaying surgery if a definite diagnosis of IE has been established. However, this argument is controversial across the literature and several factors including the center specific experience can play a role in decision-making. In this review the latest evidences on IE clinical and surgical characteristics along with the current studies on the adoption of an early surgical approach are analyzed to clarify whether enough evidence is available to inform an update of the guidelines.

A case of transcatheter prosthetic aortic valve endocarditis

Transcatheter aortic valve implantation (TAVR) constitutes an established treatment in inoperable or high perioperative risk patients with severe aortic stenosis. Prosthetic valve endocarditis after ΤΑVR occurs with an incidence of 0.3–1% per patient-year. Infective endocarditis may stem from hematogenous dissemination or contact with infected adherent tissue. Few cases of infective endocarditis after TAVR have been reported. We present an interesting case of a 79-year-old male with a history of severe aortic stenosis status post TAVR greater than one year ago, and pulmonary vein isolation for atrial fibrillation six weeks ago was found to have infective endocarditis with a vegetation on the prosthetic valve leading to multiple embolic strokes as a result of Enterococcus faecalis bacteremia. The patient was not a surgical candidate with his Society of Thoracic Surgery (STS) risk score being 18%; therefore, he was managed conservatively on intravenous antibiotics. Our case had endocarditis from enterococcus bacteremia; however, the patient never had any gastrointestinal or genitourinary procedure.

Current AATS guidelines on surgical treatment of infective endocarditis

The 2016 American Association for Thoracic Surgery (AATS) guidelines for surgical treatment of infective endocarditis (IE) are question based and address questions of specific relevance to cardiac surgeons. Clinical scenarios in IE are often complex, requiring prompt diagnosis, early institution of antibiotics, and decision-making related to complications, including risk of embolism and timing of surgery when indicated. The importance of an early, multispecialty team approach to patients with IE is emphasized. Management issues are divided into groups of questions related to indications for and timing of surgery, pre-surgical work-up, preoperative antibiotic treatment, surgical risk assessment, intraoperative management, surgical management, surveillance, and follow up. Standard indications for surgery are severe heart failure, severe valve dysfunction, prosthetic valve infection, invasion beyond the valve leaflets, recurrent systemic embolization, large mobile vegetations, or persistent sepsis despite adequate antibiotic therapy for more than 5-7 days. The guidelines emphasize that once an indication for surgery is established, the operation should be performed as soon as possible. Timing of surgery in patients with strokes and neurologic deficits require close collaboration with neurological services. In surgery infected and necrotic tissue and foreign material is radically debrided and removed. Valve repair is performed whenever possible, particularly for the mitral and tricuspid valves. When simple valve replacement is required, choice of valve-mechanical or tissue prosthesis-should be based on normal criteria for valve replacement. For patients with invasive disease and destruction, reconstruction should depend on the involved valve, severity of destruction, and available options for cardiac reconstruction. For the aortic valve, use of allograft is still favored.

"A contemporary description of staphylococcus aureus prosthetic valve endocarditis. Differences according to the time elapsed from surgery"

Staphylococcus aureus prosthetic valve endocarditis (SAPVE) has a poor prognosis. There are no large series that accurately describe this entity.This is a retrospective observational study on a prospective cohort from 3 Spanish reference hospitals for cardiac surgery, including 78 definitive episodes of left SAPVE between 1996 and 2016.Fifty percent had a Charlson Index score >5; 53% were health care-related. Twenty percent did not present fever. Complications at diagnosis included: severe heart failure (HF, 29%), septic shock (SS, 17.9%), central nervous system abnormalities (19%), septic metastasis (4%). Hemorrhagic stroke was not higher in anticoagulated patients. Twenty-seven percent were methicilin-resistant SA (MRSA). Fifteen of 31 had positive valve culture; it was related to surgery within first 24 hours. At diagnosis, 69% had vegetation (>10 mm in 75%), 21.8% perianular extension, and 20% prosthetic dehiscence. Forty-eight percent had persistent bacteremia, related to nonsurgical treatment. Perianular extension progressed in 18%. Surgery was performed in 35 episodes (12 with stroke). Eleven uncomplicated episodes were managed with medical therapy, 8 survived. In-hospital mortality was 55%, higher in episodes with hemorrhagic stroke (77.8% vs 52.2%, odds ratio 3.2 [0.62-16.55]). Early SAPVE was nosocomial (92%), presented as severe HF (54%), patients were diagnosed and operated on early, 38% died. In intermediate SAPVE (9 weeks-1 year) diagnosis was delayed (24%), patients presented with constitutional syndrome (18%), renal failure (41%), and underwent surgery >72 hours after indication; 53% died. Late SAPVE (>1 year) was related with health care, diagnosis delay, and 60% of deceases.Left SAPVE frequently affected patients with comorbidity and health care contact. Complications at diagnosis and absence of fever were frequent. Presence of MRSA was high. Positive valve culture was related to early surgery. Paravalvular extension was frequent; vegetations were large, but its absence at diagnosis was common. Some uncomplicated SAPVE episodes were safety treated with medical therapy. Surgery was feasible in patients with stroke. Mortality was high. There were differences in some clinical characteristics and in evolution according to the time elapsed from valve replacement. Prognosis was better in early SAPVE.

Current and emerging pharmacotherapy for the treatment of infections following open-heart surgery

INTRODUCTION

Patients undergoing open-heart surgery may suffer from postoperative complications, including severe infections. Antimicrobials to treat infectious complications in this population should be selected thoughtfully, taking into account three different and fundamental issues: (i) the site of infection; (ii) the suspected or proven causative agent and its susceptibility pattern; and (iii) the risk of suboptimal pharmacokinetic characteristics and potential toxicity of the chosen drug/s.

AREAS COVERED

The present narrative review summarizes the current and future antimicrobial options for the treatment of infections developing after open-heart surgery.

EXPERT OPINION

The pharmacological treatment of infections developing in cardiac surgery patients poses peculiar challenges, including the need for an active empirical therapy for severe events such as bloodstream infections, deep sternal wound infections, or early-onset postoperative prosthetic endocarditis. In addition, the risk for multidrug-resistant pathogens should also be taken into account in endemic areas. A multidisciplinary evaluation on a patient-by-patient basis, deeply involving infectious diseases specialists and cardiothoracic surgeons, remains essential for appropriately balancing both short-term and long-term risks and benefits of any possible surgical reintervention in combination with adequate pharmacotherapy.

Outcomes of Transvenous Lead Extraction for Cardiovascular Implantable Electronic Device Infections in Patients With Prosthetic Heart Valves

Background—

Lead-related or valve-related endocarditis can complicate cardiovascular implantable electronic device (CIED) infection in patients with both CIED and prosthetic valves. The objective of this study was to determine the outcomes of transvenous lead extraction for CIED infection in patients with prosthetic valves.

Methods and Results—

We retrospectively screened 794 transvenous lead extraction procedures, between September 1, 2001 and August 31, 2012, at Mayo Clinic to identify patients with prosthetic valves who underwent lead extraction for infection. Demographic, clinical, and follow-up characteristics were analyzed. In total, 51 patients (6%) met the study inclusion criteria, of whom 20 had pocket infection and 31 had lead-related or valve-related, or both, endocarditis or bloodstream infection (mean age, 67 [18] years). Staphylococcal species were the most common pathogens, including Staphylococcus aureus in 20 cases (39%) and coagulase-negative staphylococci in 19 cases (37%). Overall, 127 transvenous leads (median lead age, 52 months) were extracted. Of these leads, 123 (97%) were removed completely. The in-hospital mortality rate was 9.8%; no deaths were attributable to the extraction procedure. Ninety-five percent of patients who survived had no evidence of recurrent device-related or valve-related infection.

Conclusions—

Transvenous lead extraction seems safe and curative in patients with CIED infection and prosthetic valves. Cure of infection can be achieved in the majority of patients with complete CIED removal and antimicrobial therapy and without valve surgery.

Late postoperative prosthetic pulmonary valve endocarditis in a 13-year-old girl with repaired tetralogy of fallot

Prosthetic pulmonary valve endocarditis has infrequently been described outside large cohort reviews, which have typically focused on infections of the left-sided heart valves. Hence, the pathogenesis, clinical presentation, and management principles of prosthetic pulmonary valve endocarditis have not been well differentiated from those of infected aortic and mitral valves. More patients with repaired tetralogy of Fallot are reaching adulthood and will need pulmonary valve implantation. Consequently, a focus on this infrequent but serious cardiac infection is needed, to learn what characteristics might distinguish it from infections of left-sided heart valves. We report the case of a 13-year-old girl with repaired tetralogy of Fallot who presented with fever and nonspecific symptoms. The patient initially failed to meet the Duke criteria for endocarditis but was then found to have endocarditis of her prosthetic pulmonary valve. We explanted the valve and replaced it with a pulmonary homograft, after which the patient had no infectious sequelae. In addition to presenting the patient's case, we review the literature on surgically inserted prosthetic pulmonary valves and discuss the primary management concerns when those valves become infected with endocarditis.

Impact of early valve surgery on outcome of Staphylococcus aureus prosthetic valve infective endocarditis: analysis in the International Collaboration of Endocarditis-Prospective Cohort Study

BACKGROUND

The impact of early valve surgery (EVS) on the outcome of Staphylococcus aureus (SA) prosthetic valve infective endocarditis (PVIE) is unresolved. The objective of this study was to evaluate the association between EVS, performed within the first 60 days of hospitalization, and outcome of SA PVIE within the International Collaboration on Endocarditis-Prospective Cohort Study.

METHODS

Participants were enrolled between June 2000 and December 2006. Cox proportional hazards modeling that included surgery as a time-dependent covariate and propensity adjustment for likelihood to receive cardiac surgery was used to evaluate the impact of EVS and 1-year all-cause mortality on patients with definite left-sided S. aureus PVIE and no history of injection drug use.

RESULTS

EVS was performed in 74 of the 168 (44.3%) patients. One-year mortality was significantly higher among patients with S. aureus PVIE than in patients with non-S. aureus PVIE (48.2% vs 32.9%; P = .003). Staphylococcus aureus PVIE patients who underwent EVS had a significantly lower 1-year mortality rate (33.8% vs 59.1%; P = .001). In multivariate, propensity-adjusted models, EVS was not associated with 1-year mortality (risk ratio, 0.67 [95% confidence interval, .39-1.15]; P = .15).

CONCLUSIONS

In this prospective, multinational cohort of patients with S. aureus PVIE, EVS was not associated with reduced 1-year mortality. The decision to pursue EVS should be individualized for each patient, based upon infection-specific characteristics rather than solely upon the microbiology of the infection causing PVIE.

Management strategies and outcome for prosthetic valve endocarditis

The aim of this study was to assess the impact of an operative protocol with a multidisciplinary approach on the outcome of patients with prosthetic valve endocarditis (PVE). A formal policy for the care of PVE was introduced at our hospital in 2003 in which patients were referred to and managed by a preexisting team involving a cardiologist, a specialist in infectious diseases, and a cardiac surgeon. All patients underwent transesophageal echocardiography as soon as clinical suspicion of PVE arose. If high-risk conditions such as heart failure, ring abscess, conditions associated with impending malfunctioning of the prosthesis, or vegetations at high risk for systemic embolization were found during the initial multidisciplinary evaluation (performed within 12 hours of admission), patients were operated on within 48 hours. Stable patients were evaluated weekly by the multidisciplinary team, and on-treatment surgery was performed whenever high-risk conditions developed or when there was persistent fever/bacteremia after 1 week of adequate antibiotic therapy. Comparing the period 2003 through 2009 with 1996 through 2002 (when a multidisciplinary policy was not followed), patients with PVE were more numerous (61 vs 38), older (mean age 68.3 vs 63.1, p = 0.01), and had more co-morbidities (mean Charlson index 3.15 vs 2.42, p = 0.03). The most frequent causative organisms were Staphylococci in both periods. In the second period, fewer patients had delayed diagnosis (39% vs 71%, p = 0.03), heart failure (20% vs 45%, p = 0.01), abscess (20% vs 39%, p = 0.04), culture-negative infective endocarditis (11% vs 29%, p = 0.03), and worsened renal function (21% vs 42%, p = 0.04). A significant reduction in in-hospital mortality (53% to 23%, p = 0.04) and 3-year mortality (60% to 28%, p = 0.001) was observed, driven by the increased number of patients successfully treated with medical therapy alone (44% vs 16%, p = 0.04). In conclusion, formalized, collaborative management led to significant improvement in PVE-related mortality.

Effect of electrical stimulus parameters on the development and propagation of action potentials in short excitable fibres

Intracellular action potentials (IAPs) produced by short fibres in response to their electrical stimulation were analysed. IAPs were calculated on the basis of the Hodgkin-Huxley (1952) model by the method described by Joyner et al. (1978). Principal differences were found in processes of activation of short (semilength L less than 5 lambda) and long fibres under near-threshold stimulation. The shorter the fibre, the lower was the threshold value (Ithr). Dependence of the latency on the stimulus strength (Ist) was substantially non-linear and was affected by the fibre length. Both fibre length and stimulus strength influenced the IAP amplitude, the instantaneous propagation velocity (IPV) and the site of the first origin of the IAP (and, consequently, excitability of the short fibre membrane). With L less than or equal to 2 lambda and Ithr less than or equal to Ist less than or equal to 1.1Ithr, IPV could reach either very high values (so that all the fibre membrane fired practically simultaneously) or even negative values. The latter corresponded to the first origin of the propagated IAP, not at the site of stimulation but at the fibre termination or at a midpoint. The characters of all the above dependencies were unchanged irrespective of the manner of approaching threshold (variation of stimulus duration or its strength). Reasons for differences in processes of activation of short and long fibres are discussed in terms of electrical load and latency. Applications of the results to explain an increased jitter, velocity recovery function and velocity-diameter relationship are also discussed.