Medical versus surgical management of Staphylococcus aureus prosthetic valve endocarditis

The Surgical Treatment of Infective Endocarditis: A Comprehensive Review

Infective endocarditis (IE) is a severe cardiac complication with high mortality rates, especially when surgical intervention is delayed or absent. This review addresses the expanding role of surgery in managing IE, focusing on the variation in surgical treatment rates, the impact of patient demographics, and the effectiveness of different surgical approaches. Despite varying global data, a notable increase in surgical interventions for IE is evident, with over 50% of patients undergoing surgery in tertiary centres. This review synthesizes information from focused literature searches up to July 2023, covering preoperative to postoperative considerations and surgical strategies for IE. Key preoperative concerns include accurate diagnosis, appropriate antimicrobial treatment, and the timing of surgery, which is particularly crucial for patients with heart failure or at risk of embolism. Surgical approaches vary based on valve involvement, with mitral valve repair showing promising outcomes compared to replacement. Aortic valve surgery, traditionally favouring replacement, now includes repair as a viable option. Emerging techniques such as sutureless valves and aortic homografts are explored, highlighting their potential advantages in specific IE cases. The review also delves into high-risk groups like intravenous drug users and the elderly, emphasizing the need for tailored surgical strategies. With an increasing number of patients presenting with prosthetic valve endocarditis and device-related IE, the review underscores the importance of comprehensive management strategies encompassing surgical and medical interventions. Overall, this review provides a comprehensive overview of current evidence in the surgical management of IE, highlighting the necessity of a multidisciplinary approach and ongoing research to optimize patient outcomes.

Antibiotic Myths for the Infectious Diseases Clinician

Antimicrobials are commonly prescribed and often misunderstood. With more than 50% of hospitalized patients receiving an antimicrobial agent at any point in time, judicious and optimal use of these drugs is paramount to advancing patient care. This narrative will focus on myths relevant to nuanced consultation from infectious diseases specialists, particularly surrounding specific considerations for a variety of antibiotics.

Clinical presentation, microbiology, and prognostic factors of prosthetic valve endocarditis. Lessons learned from a large prospective registry

BACKGROUND

Prosthetic valve endocarditis (PVE) is a serious infection associated with high mortality that often requires surgical treatment.

METHODS

Study on clinical characteristics and prognosis of a large contemporary prospective cohort of prosthetic valve endocarditis (PVE) that included patients diagnosed between January 2008 and December 2020. Univariate and multivariate analysis of factors associated with in-hospital mortality was performed.

RESULTS

The study included 1354 cases of PVE. The median age was 71 years with an interquartile range of 62-77 years and 66.9% of the cases were male. Patients diagnosed during the first year after valve implantation (early onset) were characterized by a higher proportion of cases due to coagulase-negative staphylococci and Candida and more perivalvular complications than patients detected after the first year (late onset). In-hospital mortality of PVE in this series was 32.6%; specifically, it was 35.4% in the period 2008-2013 and 29.9% in 2014-2020 (p = 0.031). Variables associated with in-hospital mortality were: Age-adjusted Charlson comorbidity index (OR: 1.15, 95% CI: 1.08-1.23), intracardiac abscess (OR:1.78, 95% CI:1.30-2.44), acute heart failure related to PVE (OR: 3. 11, 95% CI: 2.31-4.19), acute renal failure (OR: 3.11, 95% CI:1.14-2.09), septic shock (OR: 5.56, 95% CI:3.55-8.71), persistent bacteremia (OR: 1.85, 95% CI: 1.21-2.83) and surgery indicated but not performed (OR: 2.08, 95% CI: 1.49-2.89). In-hospital mortality in patients with surgical indication according to guidelines was 31.3% in operated patients and 51.3% in non-operated patients (p<0.001). In the latter group, there were more cases of advanced age, comorbidity, hospital acquired PVE, PVE due to Staphylococcus aureus, septic shock, and stroke.

CONCLUSIONS

Not performing cardiac surgery in patients with PVE and surgical indication, according to guidelines, has a significant negative effect on in-hospital mortality. Strategies to better discriminate patients who can benefit most from surgery would be desirable.

Current recommendations and uncertainties for surgical treatment of infective endocarditis: a comparison of American and European cardiovascular guidelines

Surgery is an effective therapy in the treatment of left-sided infective endocarditis (IE) in patients for whom antibiotic treatment alone is unlikely to be curative or may be associated with ongoing risk of complications. However, the interplay between indication for surgery, its risk, and timing is complex and there continue to be challenges in defining the effects of surgery on disease-related outcome. Guidelines published by the American College of Cardiology/American Heart Association and the European Society of Cardiology provide recommendations for the use of surgery in IE, but these are limited by a low level of evidence related to predominantly observational studies with inherent selection and survival biases. Evidence to guide the timing of surgery in IE is less robust, and predominantly based on expert consensus. Delays between IE diagnosis and recognition of an IE complication as a surgical indication and transfers to surgical centres also impact surgical timing. This comparison of the two guidelines exposes areas of uncertainty and gaps in current evidence for the use of surgery in IE across different indications, particularly related to its timing and consideration of operative risk.

Transcatheter Aortic Valve Implantation: The Evolving Role of the Radiologist in 2021

BACKGROUND

 Transcatheter aortic valve implantation (TAVI) has gained worldwide acceptance and implementation as an alternative therapeutic option in patients with severe aortic valve stenosis unable to safely undergo surgical aortic valve replacement. This transformative technique places the radiologist in a key position in the pre-procedural assessment of potential candidates for this technique, delivering key anatomical information necessary for patient eligibility and procedural safety. Recent trials also provide encouraging results to potentially extend the indication to patients with safer risk profiles.

METHOD

 The review is based on a PubMed literature search using the search terms "transcatheter heart valve", "TAVI", "TAVR", "CT", "imaging", "MR" over a period from 2010-2020, combined with personal comments based on the author's experience.

RESULTS AND CONCLUSION

 CT plays a prominent role in the pre-procedural workup, delivering as a true 3D imaging modality optimal visualization of the complex anatomy of the aortic root with simultaneous evaluation of the patency of the different access routes. As such, the contribution of CT is key for the determination of patient eligibility and procedural safety. This input is supplementary to the contributions of other imaging modalities and forms an important element in the discussions of the Heart Valve Team. Knowledge of the procedure and its characteristics is necessary in order to provide a comprehensive and complete report. While the role of CT in the pre-procedural evaluation is well established, the contribution of CT and MR and the clinical significance of their findings in the routine follow-up after the intervention are less clear and currently the subject of intense investigation. Important issues remain, including the occurrence and significance of subclinical leaflet thrombosis, prosthetic heart valve endocarditis, and long-term structural valve degeneration.

KEY POINTS

  · CT plays a crucial role in evaluating transcatheter heart valve candidates. · Evaluation must include the dimensions of the aortic root and access paths. · The exact post-procedural role of CT and MRI has not yet been determined..

CITATION FORMAT

· Salgado R, El Addouli H, Budde RP. Transcatheter Aortic Valve Implantation: The Evolving Role of the Radiologist in 2021. Fortschr Röntgenstr 2021; 193: 1411 - 1425.

Surgical therapy of infective endocarditis following interventional or surgical pulmonary valve replacement

OBJECTIVES

Percutaneous pulmonary valve prostheses and right ventricle-to-pulmonary artery conduits are at risk for infective endocarditis (IE). In children and adults with a congenital heart disease, a pulmonary valve implant is frequently necessary. Prosthetic valve endocarditis is a conservatively barely manageable, serious life-threatening condition. We investigated the results of surgical pulmonary valve replacements in patients with IE.

METHODS

A total of 20 patients with congenital heart disease with the definite diagnosis of IE between March 2013 and July 2020 were included in this single institutional, retrospective review. Infected conduits were 11 Melody, 5 Contegra, 3 homografts and 1 Matrix P Plus. All of the infected prosthetic material was removed from the right ventricular outflow tract up to the pulmonary bifurcation. Pulmonary homografts were implanted after pulmonary root resection as right ventricle-to-pulmonary artery conduits.

RESULTS

All patients survived and were discharged infection-free. The mean time from the conduit implant to the operation for IE was 4.9 years [95% confidence interval (CI), 3.0-6.9]. The median intensive care unit stay was 3.0 days (95% CI, 2.0-4.7), and the median hospital time was 25.0 days (95% CI, 19.2-42.0). Median follow-up time was 204.5 days (range 30 days to 5 years) without death or recurrent endocarditis.

CONCLUSIONS

The surgical treatment of IE of percutaneous pulmonary valve prostheses and right ventricle-to-pulmonary artery conduits is a safe and effective therapeutic concept. Early surgical referral of patients with suspicion of IE should be pursued to avoid sequelae such as right ventricular failure, septic emboli, intracardiac expansion and antibiotic resistance.

Impact of surgical timing on survival in patients with infective endocarditis: a time-dependent analysis

The purpose of this study was to evaluate the impact of surgical timing on survival in patients with left-sided infective endocarditis (IE). This was a retrospective study including 313 patients with left-sided IE between 2009 and 2017. Surgery was defined as urgent (US) or early (ES) if performed within 7 or 28 days, respectively. A multivariable Cox regression analysis including US and ES as time-dependent variables was performed to assess the impact on 1-year mortality. ES was associated with a better survival (aHR 0.349, 95% CI 0.135-0.902), as US (aHR 0.262, 95% CI 0.075-0.915). ES and US were associated with a better prognosis in patients with left-sided IE.

Improving the Diagnostic Performance of 18F-Fluorodeoxyglucose Positron-Emission Tomography/Computed Tomography in Prosthetic Heart Valve Endocarditis

BACKGROUND

¹⁸F-Fluorodeoxyglucose (FDG) positron-emission tomography/computed tomography (PET/CT) was recently introduced as a new tool for the diagnosis of prosthetic heart valve endocarditis (PVE). Previous studies reporting a modest diagnostic accuracy may have been hampered by unstandardized image acquisition and assessment, and several confounders, as well. The aim of this study was to improve the diagnostic performance of FDG PET/CT in patients in whom PVE was suspected by identifying and excluding possible confounders, using both visual and standardized quantitative assessments.

METHODS

In this multicenter study, 160 patients with a prosthetic heart valve (median age, 62 years [43-73]; 68% male; 82 mechanical valves; 62 biological; 9 transcatheter aortic valve replacements; 7 other) who underwent FDG PET/CT for suspicion of PVE, and 77 patients with a PV (median age, 73 years [65-77]; 71% male; 26 mechanical valves; 45 biological; 6 transcatheter aortic valve replacements) who underwent FDG PET/CT for other indications (negative control group), were retrospectively included. Their scans were reassessed by 2 independent observers blinded to all clinical data, both visually and quantitatively on available European Association of Nuclear Medicine Research Ltd-standardized reconstructions. Confounders were identified by use of a logistic regression model and subsequently excluded.

RESULTS

Visual assessment of FDG PET/CT had a sensitivity/specificity/positive predictive value/negative predictive value for PVE of 74%/91%/89%/78%, respectively. Low inflammatory activity (C-reactive protein <40 mg/L) at the time of imaging and use of surgical adhesives during prosthetic heart valve implantation were significant confounders, whereas recent valve implantation was not. After the exclusion of patients with significant confounders, diagnostic performance values of the visual assessment increased to 91%/95%/95%/91%. As a semiquantitative measure of FDG uptake, a European Association of Nuclear Medicine Research Ltd-standardized uptake value ratio of ≥2.0 was a 100% sensitive and 91% specific predictor of PVE.

CONCLUSIONS

Both visual and quantitative assessments of FDG PET/CT have a high diagnostic accuracy in patients in whom PVE is suspected. FDG PET/CT should be implemented early in the diagnostic workup to prevent the negative confounding effects of low inflammatory activity (eg, attributable to prolonged antibiotic therapy). Recent valve implantation was not a significant predictor of false-positive interpretations, but surgical adhesives used during implantation were.

"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.

Methicillin-Resistant Staphylococcus aureus Prosthetic Valve Endocarditis: Pathophysiology, Epidemiology, Clinical Presentation, Diagnosis, and Management

Staphylococcus aureus prosthetic valve endocarditis (PVE) remains among the most morbid bacterial infections, with mortality estimates ranging from 40% to 80%. The proportion of PVE cases due to methicillin-resistant Staphylococcus aureus (MRSA) has grown in recent decades, to account for more than 15% of cases of S. aureus PVE and 6% of all cases of PVE. Because no large studies or clinical trials for PVE have been published, most guidelines on the diagnosis and management of MRSA PVE rely upon expert opinion and data from animal models or related conditions (e.g., coagulase-negative Staphylococcus infection). We performed a review of the literature on MRSA PVE to summarize data on pathogenic mechanisms and updates in epidemiology and therapeutic management and to inform diagnostic strategies and priority areas where additional clinical and laboratory data will be particularly useful to guide therapy. Major updates discussed in this review include novel diagnostics, indications for surgical management, the utility of aminoglycosides in medical therapy, and a review of newer antistaphylococcal agents used for the management of MRSA PVE.

Management Considerations in Infective Endocarditis: A Review

IMPORTANCE

Infective endocarditis occurs in approximately 15 of 100 000 people in the United States and has increased in incidence. Clinicians must make treatment decisions with respect to prophylaxis, surgical management, specific antibiotics, and the length of treatment in the setting of emerging, sometimes inconclusive clinical research findings.

OBSERVATIONS

Community-associated infective endocarditis remains the predominant form of the disease; however, health care accounts for one-third of cases in high-income countries. As medical interventions are increasingly performed on older patients, the disease incidence from cardiac implanted electronic devices is also increasing. In addition, younger patients involved with intravenous drug use has increased in the past decade and with it the proportion of US hospitalization has increased to more than 10%. These epidemiological factors have led to Staphylococcus aureus being the most common cause in high-income countries, accounting for up to 40% of cases. The mainstays of diagnosis are still echocardiography and blood cultures. Adjunctive imaging such as cardiac computed tomographic and nuclear imaging can improve the sensitivity for diagnosis when echocardiography is not conclusive. Serological studies, histopathology, and polymerase chain reaction assays have distinct roles in the diagnosis of infective endocarditis when blood culture have tested negative with the highest yield obtained from serological studies. Increasing antibiotic resistance, particularly to S aureus, has led to a need for different antibiotic treatment options such as newer antibiotics and combination therapy regimens. Surgery can confer a survival benefit to patients with major complications; however, the decision to pursue surgery must balance the risks and benefits of operations in these frequently high-risk patients.

CONCLUSIONS AND RELEVANCE

The epidemiology and management of infective endocarditis are continually changing. Guidelines provide specific recommendations about management; however, careful attention to individual patient characteristics, pathogen, and risk of sequela must be considered when making therapeutic decisions.

Gentamicin may have no effect on mortality of staphylococcal prosthetic valve endocarditis

PURPOSE

To analyze the influence of adding gentamicin to a regimen consisting of β-lactam or vancomycin plus rifampicin on survival in patients suffering from Staphylococcal prosthetic valve endocarditis (SPVE).

METHODS

From January 2008 to September 2016, 334 patients with definite SPVE were attended in the participating hospitals. Ninety-four patients (28.1%) received treatment based on β-lactam or vancomycin plus rifampicin and were included in the study. Variables were analyzed which related to patient survival during admission, including having received treatment with gentamicin.

RESULTS

Seventy-seven (81.9%) were treated with cloxacillin (or vancomycin) plus rifampicin plus gentamicin, and 17 patients (18.1%) received the same regimen without gentamicin. The causative microorganism was Staphylococcus aureus in 40 cases (42.6%) and coagulase-negative staphylococci in 54 cases (57.4%). Overall, 40 patients (42.6%) died during hospital admission, 33 patients (42.9%) in the group receiving gentamicin and 7 patients in the group that did not (41.2%, P = 0.899). Worsening renal function was observed in 42 patients (54.5%) who received gentamicin and in 9 patients (52.9%) who did not (p = 0.904). Heart failure as a complication of endocarditis (OR: 4.58; CI 95%: 1.84-11.42) and not performing surgery when indicated (OR: 2.68; CI 95%: 1.03-6.94) increased mortality. Gentamicin administration remained unrelated to mortality (OR: 1.001; CI 95%: 0.29-3.38) in the multivariable analysis.

CONCLUSIONS

The addition of gentamicin to a regimen containing vancomycin or cloxacillin plus rifampicin in SPVE was not associated to better outcome.

Endocarditis after interventional repair of the mitral valve: Review of a dilemma

BACKGROUND

The MitraClip procedure can be an alternative treatment option for patients with high surgical risk for whom surgical treatment is contraindicated. Patients with prosthetic material have an increased risk for infective endocarditis.

HYPOTHESIS

Incidence, treatment and outcome of patients with endocarditis after interventional mitral valve repair are not known.

METHODS

We searched for articles using PubMed using the terms "interventional mitral valve repair", "mitraclip" and "endocarditis". We have also searched for case reports in major congresses. Furthermore, we report two cases.

RESULTS

Four cases of IE after MitraClip were found in addition to our cases. The leading cause is a bacterial infection, typically with staphylococcal bacteria. Approximately two thirds of these patients underwent surgery. Short-term outcome seems to be reasonable for these patients. During the early postoperative period and if Staphylococcus aureus can be cultivated mortality seems to be significantly elevated.

CONCLUSION

IE after MitraClip procedure is a dilemma. While surgical bail-out seems to be the favorable treatment option, patients were rejected conventional surgery in first place due to their high operative risk. Best treatment recommendation must be made on an individual basis. Predisposing factors should be conscientiously addressed prior to the procedure.

Surgical Versus Medical Therapy for Prosthetic Valve Endocarditis: A Meta-Analysis of 32 Studies

Prosthetic valve endocarditis (PVE) is associated with significant morbidity, and the optimal treatment strategy has not been clearly defined. A systematic review and meta-analysis of 32 studies comparing valve reoperation and medical therapy was performed; it included 2,636 patients, with a mean follow-up of 22 months. A valve reoperation was associated with a lower risk of 30-day mortality, greater survival at follow-up, and a similar rate of PVE recurrence. Prospective studies are warranted to confirm these findings and to clarify clinical decision-making regarding the timing and necessity of a valve reoperation, as opposed to treatment with medical therapy alone.

Comparison of prognoses of Staphylococcus aureus left-sided prosthetic endocarditis and prosthetic endocarditis caused by other pathogens

BACKGROUND

Staphylococcus aureus prosthetic valve endocarditis (SAPIE) is a serious disease.

AIMS

Our objective was to study the clinical, echocardiographic and prognostic characteristics of left-sided SAPIE, and to compare these characteristics with those of left-sided non-S. aureus prosthetic infective endocarditis (NSAPIE) (i.e. left-sided prosthetic infective endocarditis caused by another germ).

METHODS

This was a retrospective analysis of 35 cases of SAPIE among 247 cases of left-sided prosthetic valve endocarditis hospitalized at two university hospitals (Amiens and Marseille, France).

RESULTS

SAPIE accounted for 14.1% of the cases of left-sided prosthetic valve endocarditis. SAPIE complications included heart failure (in 42.8% of cases), acute renal failure (in 51.4%), sepsis (in 51.4%), neurological events (in 31.4%), systemic embolic event (in 34.2%) and abscess (in 60.0%). In-hospital mortality occurred in 48.5% of SAPIE cases compared with 16% of NSAPIE cases. A comparison of the SAPIE and NSAPIE groups showed a significant difference in terms of 4-year survival (31.8±7.3% vs 60.1±4.1%; P=0.001). Severe sepsis was the only prognostic factor associated with in-hospital mortality (odds ratio 5.7; P=0.03) and long-term mortality (odds ratio 3.7; P=0.01) in cases of SAPIE. Sepsis-induced multiple organ dysfunction syndrome was the main cause of in-hospital mortality (70.5%).

CONCLUSIONS

SAPIE is a very serious disease, with elevated in-hospital mortality resulting from sepsis-induced multiple organ dysfunction syndrome. Emergency surgery is recommended in these cases, when possible, before the occurrence of complications, especially severe sepsis.

Staphylococcus aureus infections: epidemiology, pathophysiology, clinical manifestations, and management

Staphylococcus aureus is a major human pathogen that causes a wide range of clinical infections. It is a leading cause of bacteremia and infective endocarditis as well as osteoarticular, skin and soft tissue, pleuropulmonary, and device-related infections. This review comprehensively covers the epidemiology, pathophysiology, clinical manifestations, and management of each of these clinical entities. The past 2 decades have witnessed two clear shifts in the epidemiology of S. aureus infections: first, a growing number of health care-associated infections, particularly seen in infective endocarditis and prosthetic device infections, and second, an epidemic of community-associated skin and soft tissue infections driven by strains with certain virulence factors and resistance to β-lactam antibiotics. In reviewing the literature to support management strategies for these clinical manifestations, we also highlight the paucity of high-quality evidence for many key clinical questions.

Predicting Risk of Endocarditis Using a Clinical Tool (PREDICT): Scoring System to Guide Use of Echocardiography in the Management of Staphylococcus aureus Bacteremia

BACKGROUND

Infective endocarditis (IE) is a serious complication of Staphylococcus aureus bacteremia (SAB). There is limited clinical evidence to guide use of echocardiography in the management of SAB cases.

METHODS

Baseline and 12-week follow-up data of all adults hospitalized at our institution with SAB from 2006 to 2011 were reviewed. Clinical predictors of IE were identified using multivariable logistic regression analysis.

RESULTS

Of the 757 patients screened, 678 individuals with SAB (24% community acquired, 56% healthcare associated, and 20% nosocomial) met study criteria. Eighty-five patients (13%) were diagnosed with definite IE within the 12 weeks of initial presentation based on modified Duke criteria. The proportion of patients with IE was 22% (36/166) in community-acquired SAB, 11% (40/378) in community-onset healthcare-associated SAB, and 7% (9/136) in nosocomial SAB. Community-acquired SAB, presence of cardiac device, and prolonged bacteremia (≥ 72 hours) were identified as independent predictors of IE in multivariable analysis. Two scoring systems, day 1 (SAB diagnosis day) and day 5 (when day 3 culture results are known), were derived based on the presence of these risk factors, weighted in magnitude by the corresponding regression coefficients. A score of ≥ 4 for day 1 model had a specificity of 96% and sensitivity of 21%, whereas a score of <2 for day 5 model had a sensitivity of 98.8% and negative predictive value of 98.5%.

CONCLUSIONS

We propose 2 novel scoring systems to guide use of echocardiography in SAB cases. Larger prospective studies are needed to validate the classification performance of these scoring systems.

Predictors of In-hospital Adverse Events in Patients with Prosthetic Valve Infective Endocarditis

BACKGROUND

We aimed to study patients with prosthetic valve endocarditis (PVE) and analyse factors associated with in-hospital adverse events.

METHODS

A review of all patients who underwent echocardiography at a local university hospital with definite PVE (modified Duke's criteria) was performed. Adverse events of in-hospital mortality and redo valve surgery were identified.

RESULTS

There were 23 patients with PVE (median age 53 years (IQR:38-66), 12 males (52%)). Twelve adverse events occurred including seven (30%) in-hospital mortalities and five (21%) redo valve surgery. Factors associated with in-hospital mortality include Staphylococcus aureus-PVE (86% vs 31%, p=0.027), presence of shock (86% vs 19%, p=0.005) and intensive care unit admission (72% vs 19%, p=0.026). Factors associated with the need for redo valve surgery include a younger median age (37 vs 61 years, p=0.012), longer median length of stay (58 vs 17 days, p=0.004), history of intravenous drug abuse (IVDA) (60% vs 6%, p=0.021) and right-sided valvular involvement (40% vs 0%, p=0.040). Using a composite endpoint of both outcomes, factors associated with in-hospital adverse events were a history of IVDA (36% vs 0%, p=0.037) and presence of shock (64% vs 17%, p=0.036).

CONCLUSION

PVE carries a high risk of poor clinical outcome in terms of in-hospital mortality and the need for redo surgery.

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.

Do all patients with prosthetic valve endocarditis need surgery?

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was 'do all patients with prosthetic valve endocarditis need surgery?' Seventeen papers were found using the reported search that represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. These studies compared the outcome and survival between surgically and non-surgically treated patients with prosthetic valve endocarditis. Of these studies, two were prospective observational studies and the rest were retrospective studies. The results of most of these papers were in accordance with the guidelines of the American College of Cardiology and American Heart association. These studies showed that unless a patient is not a surgical candidate, an operation is the treatment of choice in prosthetic valve endocarditis. Surgery should be performed as soon as possible, particularly in haemodynamically unstable patients and those who develop complications such as heart failure, valvular dysfunction, regurgitation/obstruction, dehiscence and annular abscess. In addition to the above indications and cardiac/valvularrelated complications of prosthetic valve endocarditis, infection with Staphylococcus aureus plays an important role in the outcome, and the presence of this micro-organism should be considered an urgent surgical indication in the treatment of prosthetic valve endocarditis. Surgery should be performed before the development of any cerebral or other complications. In contrast, in stable patients with other micro-organisms, particularly those with organisms sensitive to antibiotic treatment who have no structural valvular damage or cardiac complications, surgery can be postponed. The option of surgical intervention can also be revisited if there is a change in response to the treatment. This option is reserved for selected patients only and we conclude that as soon as the diagnosis of prosthetic valve endocarditis is made, cardiac surgeons should be involved.

Prosthetic valve endocarditis: management strategies and prognosis: A ten-year analysis in a tertiary care centre in Tunisia

BACKGROUND

Prosthetic valve endocarditis (PVE) is a rare and serious complication after heart valve replacement; its optimal management strategy, though, still needs to be defined.

OBJECTIVE

To study the clinical, microbiological and echocardiographic characteristics of PVE and to analyse the influence of the adopted therapeutic strategy (medical or surgical) on short- and midterm outcome in a tertiary care centre in a developing country (Tunisia).

METHODS

All cases of PVE treated in our institution between 1997 and 2006 were retrospectively analysed according to the modified DUKE criteria.

RESULTS

A total of 48 PVE episodes were diagnosed (30 men and 18 women), mean age was 37.93 years. Twenty-eight patients (58.33%) were exclusively medically treated, whereas 20 (41.66%) were treated by a combined surgical and medical strategy. Indications for surgery were haemodynamic deterioration in eight patients (40%), annular abscess in six (30%) and persisting sepsis in six (30%). In comparison with those from the medical group, operated patients had a longer delay to diagnosis (p=0.025), were more frequently in heart failure (p=0.04) and experienced more early complications (p=0.011); they also more frequently had prosthetic dehiscence (p=0.015), annular abscesses (p=0.039) and vegetations >10 mm (p=0.008). Conversely, no differences were found between the groups in terms of age, sex, or nature of involved organisms. In-hospital mortality for the medical group was 14.28% and for the surgical group 35% (p=0.09).

CONCLUSION

PVE is a very serious condition carrying high mortality rates regardless of the adopted strategy. Our study demonstrates that, in selected patients, medical treatment could be a successful and acceptable approach. (Neth Heart J 2009;17: 56-60.).

Cardiac complications of infective endocarditis

Cardiac complications caused by infective endocarditis (IE) are varied and frequently life-threatening. This article focuses on new data related to several complications, and summarizes the indications, timing, and type of valve surgery recommended in the management of IE. Several recent studies using propensity score techniques have resulted in disparate conclusions and underscore the need for randomized prospective studies to better address whether and when surgery should be performed in patients with IE. Mitral valve repair is an exciting new development in surgical methodology and probably will have increased application over the next two decades. Excellent reviews related to periannular abscesses, fistulae, acute coronary syndrome, and pericarditis have been published recently and are also summarized.

The impact of cardiac surgery in native valve infective endocarditis: can euroSCORE guide patient selection?

BACKGROUND

Decision making regarding surgical intervention in native valve endocarditis (NVE) is often complex and surgery is withheld in a number of patients either because medical treatment is considered the best treatment or because the risk of operation is considered too high. The objective of this study was to investigate the outcome of surgical treatment and to validate the ability of euroSCORE to predict operative mortality in NVE patients.

METHODS

Prospective cohort study including 323 consecutive NVE patients. Patients were divided into 3 groups based on treatment strategy and indication/contraindication for surgery. The additive and logistic euroSCORE was calculated and the observed and predicted mortality was compared.

RESULTS

Cardiac surgery was associated with a good prognosis, in-hospital and after 12months, compared to conservative treatment. After adjustment for confounders surgery was associated with a survival benefit (hazard ratio (HR) 0.45, 95% CI: 0.27-0.76%; p=0.003). When propensity score was used in regression adjustment, cardiac surgery was still associated with a better outcome after 12months (HR 0.41, 95% CI: 0.25-0.68; p<0.001). Observed mortality for patients receiving surgical treatment was 11% compared to a mean logistic euroSCORE mortality of 16% (NS). The discriminating ability of euroSCORE was good, area under the ROC curve 0.74 (95% CI: 0.64-0.84; p<0.001) logistic model and 0.75 (95% CI: 0.65-0.86; p<0.001) additive model.

CONCLUSIONS

Cardiac surgery was associated with a good prognosis when indicated regardless of euroSCORE, and surgery should only be withheld after thorough consideration. EuroSCORE remains a valuable tool to identify high-risk IE patients when surgery is considered.

New perspectives of infections in cardiovascular disease

Infections have been recognized as significant causes of cardiac diseases for many decades. Various microorganisms have been implicated in the etiology of these diseases involving all classes of microbial agents. All components of the heart structure can be affected by infectious agents, i.e. pericardium, myocardium, endocardium, valves, autonomic nervous system, and some evidence of coronary arteries. A new breed of infections have evolved over the past three decades involving cardiac implants and this group of cardiac infectious complications will likely continue to increase in the future, as more mechanical devices are implanted in the growing ageing population. This article will review the progress made in the past decade on understanding the pathobiology of these infectious complications of the heart, through advances in genomics and proteomics, as well as potential novel approach for therapy.An up-to-date, state-of-the-art review and controversies will be outlined for the following conditions: (i) perimyocarditis; (ii) infective endocarditis; (iii) cardiac device infections; (iv) coronary artery disease and potential role of infections.

Infective endocarditis due to Propionibacterium species

Propionibacterium species rarely cause infective endocarditis. When identified in blood cultures, they may be inappropriately disregarded as skin flora contaminants. The purpose of this study was to characterize the clinical presentation and management of endocarditis due to Propionibacterium species. All cases of endocarditis due to Propionibacterium species that were treated at the Mayo Clinic, Rochester, USA were retrospectively reviewed, and the English language medical literature was searched for all previously published reports. Seventy cases, which included eight from the Mayo Clinic, were identified (clinical details were available for only 58 cases). The median age of patients was 52 years, and 90% were males. In 79% of the cases, the infection involved prosthetic material (39 prosthetic valves, one left ventricular Teflon patch, one mitral valve ring, one pulmonary artery prosthetic graft, three pacemakers, and one defibrillator). Blood cultures were positive in 62% of cases. All 22 cases with negative blood cultures were microbiologically confirmed by either positive valve tissue cultures (n = 21) or molecular methods (n = 1). Endocarditis was complicated by abscess formation in 36% of cases. The majority (81%) of patients underwent surgery, either for valve replacement and debridement of a cardiac abscess, or removal of an infected device. Crude in-hospital mortality was 16%. The median duration of postoperative antibiotic treatment was 42 days. Patients were commonly treated with a penicillin derivative alone or in combination with gentamicin. On the basis of the above data, it is recommended that infective endocarditis should be strongly suspected when Propionibacterium species are isolated from multiple blood cultures, particularly in the presence of a cardiovascular device.

Endocarditis caused by Staphylococcus aureus: A reappraisal of the epidemiologic, clinical, and pathologic manifestations with analysis of factors determining outcome

Staphylococcus aureus is the leading cause of infectious endocarditis and its mortality has remained high despite better diagnostic and therapeutic procedures over time. We conducted a retrospective review of 133 cases of definite S. aureus endocarditis seen at a single tertiary care hospital over 22 years to assess changes in the epidemiology and incidence of the infection, manifestations, outcome, risk factors for mortality, and impact of cardiac surgery on prognosis.Patients were classified into 2 groups: 1) right-sided endocarditis (64 patients) and 2) left-sided endocarditis (69 patients). While the number of cases of left-sided endocarditis remained steady at 1-3 cases per 10,000 admissions, the incidence of right-sided endocarditis, after a peak in the early 1990s, declined to almost disappear in 2001. Among the cases of right-sided endocarditis, we found 2 subsets of patients with different clinical features and prognosis: the first subset comprised 53 intravenous drug abusers, and the second subset comprised 11 patients with catheter-associated S. aureus bacteremia and endocarditis. Fifty-one patients were human immunodeficiency virus (HIV)-positive drug abusers, most of whom (80.3%) had right-sided endocarditis. We did not find differences in mortality between HIV-positive and HIV-negative individuals; mortality seemed to depend more on the site of the heart involved than on HIV status.Among the cases of left-sided endocarditis, the mitral valve was more commonly involved than the aortic valve (61% vs. 30%). Overall, 74% of patients with left-sided endocarditis developed 1 or more cardiac or extracardiac complication. In comparison, only 23.4% of patients with right-sided endocarditis developed complications.Prosthetic valve endocarditis (PVE) was hospital-acquired more frequently than native valve endocarditis (NVE). Patients with PVE had a shorter duration of symptoms until diagnosis and presented with or developed cardiac murmurs less frequently than patients with NVE. Cardiac failure (49%), renal failure (43%) and central nervous system (CNS) events (35%) were frequently observed in patients with both PVE and NVE. Valve replacement was more frequently needed and more rapidly performed in patients with PVE than in their counterparts with NVE.The overall mortality of patients with right-sided endocarditis was 17%. While the mortality of right-sided endocarditis in injection drug users was 3.7%, the mortality of patients with right-sided endocarditis associated with infected intravenous catheters was 82% (odds ratio [OR], 0.01; 95% confidence interval [CI], 0.001-0.07). For left-sided endocarditis mortality was 38% and was not significantly different in patients with NVE or PVE (OR, 0.65; 95% CI, 0.23-1.87). CNS complications were associated with mortality in both NVE (OR, 6.55; 95% CI, 1.78-24.04) and PVE (OR, 32; 95% CI, 2.63-465.40). Development of 2 or 3 complications was associated with an increased risk of mortality (OR, 5.59; 95% CI, 1.08-28.80 and OR, 9.25; 95% CI, 1.36-62.72 for 2 vs. 1 complication and for 3 vs. 2 complications, respectively).Surgical treatment did not significantly influence mortality in cases of NVE, (OR, 3.19; 95% CI, 0.76-13.38) but significantly improved the prognosis of patients with PVE (OR, 69; 95% CI, 2.89-1647.18).S. aureus endocarditis is an aggressive, often fatal, infection. The results of the current study suggest that valve replacement will improve the outcome of infection, particularly in patients with PVE.

Management of prosthetic valve infective endocarditis

This study analyzed the profile and outcome of surgically versus medically treated patients with prosthetic valve infective endocarditis (PVE). From 2000 to 2006, 80 patients >16 years of age (median 71) with definite PVE according to modified Duke criteria were included. The medically treated group was separated into deliberately conservative and perforce conservative treatments, the latter group including patients with contraindications to a cardiosurgical intervention. The most frequent causative micro-organisms were staphylococci. Forty-six percent of patients were surgically treated, 34% had deliberately conservative treatment, and 20% had perforce conservative treatment. Six-month mortality was 29%; 27% of surgically treated patients died, 4% deliberately conservatively patients died, and 75% perforce conservatively treated patients died. Septic shock, multiorgan failure, and type of treatment were significantly associated with death in univariable analysis. Multivariable analysis revealed that type of treatment (perforce conservative) and septic shock predicted death in patients with PVE. Survival was most favorable in deliberately conservatively treated patients, including PVE due to Staphylococcus aureus. In conclusion, there remains a role for watchful waiting in patients with PVE without evidence of major complications. Moreover, patients with uncomplicated S. aureus PVE can be treated successfully without cardiac surgery. Conversely, patients with major complicated PVE should preferentially undergo surgery. Predictors of mortality in patients with PVE included septic shock and perforce conservative treatment.

[Staphylococcus aureus bacteremia and endocarditis]

The prevalence of Stapylococcus bacteriaemia is increasing worldwide, because of the increasing use of invasive procedures leading to nosocomial infections, but also of a changing way of life (increasing fashion for tattoos or piercing, use of intravenous drugs). Infective endocarditis develops in 10-30% of the cases of staphylococcus bacteriaemia. Staphylococcus aureus endocarditis must be suspected when it develops in the year following heart surgery or implantation of permanent devices. In drug users, it usually involves the tricuspid valve. According to the resistance of the germ to meticillin, antibiotic therapy uses a combination of intravenous penicillin or glycopeptide and an aminoside. Other antibiotics such as fosfomycin, rifampicin, fusidic acid, or clindamycin can be used when aminosides are contra-indicated. The role of newer antibiotic agents, such as daptomycin or linezolide, remains to be established.

Prosthetic valve endocarditis: current approach and therapeutic options

Despite improvements in medical and surgical therapy, prosthetic valve endocarditis is still associated with a severe prognosis, and remains a diagnostic and therapeutic challenge. Diagnosis of prosthetic valve endocarditis is more difficult than that of the native valve endocarditis and the application of Duke criteria is less useful in this setting. Therapeutic strategies are not guided by evidence-based recommendations and are mainly based on a careful prognostic evaluation, which allows the identification of high-risk subgroups. Continuous effort have to be made to detect early this severe complication of valve replacement and to prevent it using systematic prophylaxis.

Surgery for infective endocarditis

Infective endocarditis (IE) is estimated to have an incidence of five to seven cases per 100,000 person-years. Although not a common clinical entity, IE is associated with substantial morbidity and risk of mortality. IE, especially infections due to Staphylococcus aureus, are increasingly healthcare-associated infections. Despite significant advances in diagnosis and management, mortality from IE has changed little since the availability of penicillin; however, this lack of improvement in mortality is likely due to an increasing number of infections from more virulent and drug-resistant pathogens coupled with infections that occur in patients with other comorbidities and those associated with prosthetic valves. Surgery is an important part of therapy for many patients, but surprisingly, little evidence is available to help clinicians determine which patients will benefit most from surgical therapy for the management of IE.

Treatment of Endocarditis: A Decade of Experience

BACKGROUND

Endocarditis represents a small proportion of cardiovascular disease but is associated with high mortality. Previous studies have reported a range of outcomes, and determinants of mortality remain poorly defined.

METHODS

The goal of this retrospective study was to identify independent variables for early and late mortality in 364 consecutive patients with endocarditis over a 10-year period.

RESULTS

The mean age of patients was 48.2 years, 35% had a history intravenous drug use, 19.8% were reoperative, and 93% had native valve endocarditis. Fever (68%) and fatigue (36%) were the most common presenting symptoms, and congestive heart failure (52%), embolization (45%), and uncontrolled sepsis (36%) were the most common indications for surgery. Overall survival at discharge, 1, 5, and 10 years was 87%, 76%, 55%, and 31%, respectively. Survival at discharge, 5, and 10 years was 91%, 69%, and 41% for surgical patients and 85%, 60%, and 31% for medically treated patients, respectively. Surgery was associated with improved short-term and long-term survival (p < 0.0.01). Independent predictors of early death were hemodynamic instability (p = 0.013) and age older than 55 years (p < 0.025). Medical treatment (p = 0.005), age older than 55 years (p = 0.032), institution (p < 0.001), New York Heart Association functional class III or IV (p = 0.002), and hemodynamic instability (p = 0.044) were predictive of late death.

CONCLUSIONS

Short-term and long-term mortality from endocarditis remains high, although surgically treated patients had improved survival. Differing outcomes from two geographically similar institutions highlight the limitations of extrapolating risk factors between disparate patient populations.

Three Fatal Cases of Rapidly Progressive Infective Endocarditis Caused by Staphylococcus Aureus One Case With Huge Vegetation

Staphylococcus aureus (S. aureus) infective endocarditis (IE) is a severe disease with a high mortality despite intensive therapy. Three cases of S. aureus IE had a rapidly progressive fatal clinical course despite intensive antimicrobial therapy. One case was methicillin-sensitive S. aureus IE, which formed rapidly growing a huge vegetation on a prosthetic mitral valve, complicated with multiple systemic emboli. The other 2 cases were methicillin-resistant S. aureus IE without any predisposing heart disease.