Prosthetic valve endocarditis: early and late outcome following medical or surgical treatment

Transcatheter heart valve explant with infective endocarditis-associated prosthesis failure and outcomes: the EXPLANT-TAVR international registry

BACKGROUND AND AIMS

Surgical explantation of transcatheter heart valves (THVs) is rapidly increasing, but there are limited data on patients with THV-associated infective endocarditis (IE). This study aims to assess the outcomes of patients undergoing THV explant for IE.

METHODS

All patients who underwent THV explant between 2011 and 2022 from 44 sites in the EXPLANT-TAVR registry were identified. Patients with IE as the reason for THV explant were compared to those with other mechanisms of bioprosthetic valve dysfunction (BVD).

RESULTS

A total of 372 patients from the EXPLANT-TAVR registry were included. Among them, 184 (49.5%) patients underwent THV explant due to IE and 188 (50.5%) patients due to BVD. At the index transcatheter aortic valve replacement, patients undergoing THV explant for IE were older (74.3 ± 8.6 vs. 71 ± 10.6 years) and had a lower Society of Thoracic Surgeons risk score [2.6% (1.8-5.0) vs. 3.3% (2.1-5.6), P = .029] compared to patients with BVD. Compared to BVD, IE patients had longer intensive care unit and hospital stays (P < .05) and higher stroke rates at 30 days (8.6% vs. 2.9%, P = .032) and 1 year (16.2% vs. 5.2%, P = .010). Adjusted in-hospital, 30-day, and 1-year mortality was 12.1%, 16.1%, and 33.8%, respectively, for the entire cohort, with no significant differences between groups. Although mortality was numerically higher in IE patients 3 years postsurgery (29.6% for BVD vs. 43.9% for IE), Kaplan-Meier analysis showed no significant differences between groups (P = .16).

CONCLUSIONS

In the EXPLANT-TAVR registry, patients undergoing THV explant for IE had higher 30-day and 1-year stroke rates and longer intensive care unit and hospital stays. Moreover, patients undergoing THV explant for IE had a higher 3-year mortality rate, which did not reach statistical significance given the relatively small sample size of this unique cohort and the reduced number of events.

A customized technique for confluent aortic annular and selective sinus of Valsalva endocarditis

We describe a novel technical modification for reoperative aortic valve replacement in destructive recurrent prosthetic aortic valve endocarditis. We encountered complex anatomy in a previously operated aortic root wherein the aortic annulus and the right coronary sinus of Valsalva were destroyed. This precluded secure suture placement. We modified a composite mechanical Valsalva conduit to create a separate sinus of Valsalva left in continuity with the mechanical valve. This approach allowed us to exclude the infected right sinus of Valsalva and the corresponding aortic annulus.

Prognosis and follow-up of patients with prosthetic valve endocarditis treated conservatively in relation to WBC-SPECT imaging

BACKGROUND

Our objective was to evaluate in patients with prosthetic valve endocarditis (PVE) treated conservatively, the prognostic value of white blood cell (WBC) signal intensity on SPECT and to describe the evolution of the WBC signal under antibiotics.

METHODS

Patients with PVE treated conservatively and positive WBC-SPECT imaging were identified retrospectively. Signal intensity was classified as intense if equal to or higher, or mild if lower, than the liver signal. Clinical, biological, imaging and follow-up information were collected from medical files.

RESULTS

Among 47 patients, WBC signal was classified as intense in 10 patients and as mild, in 37. The incidence of the primary composite endpoint (death, late cardiac surgery, or relapse) was significantly higher in patients with intense vs. mild signal (90% vs. 11%). Twenty-five patients underwent a second WBC-SPECT imaging during follow-up. The prevalence of WBC signal decreased progressively from 89% between 3 and 6 weeks to 42% between 6 and 9 weeks and 8% more than 9 weeks after initiation of antibiotics.

CONCLUSIONS

In patients with PVE treated conservatively, intense WBC signal was associated with poor outcome. WBC-SPECT imaging appears as an interesting tool for risk stratification and to monitor locally the efficacy of antibiotic treatment.

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.

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.

Infective Endocarditis Following Transcatheter Aortic Valve Replacement: Comparison of Balloon- Versus Self-Expandable Valves

BACKGROUND

No data exist about the characteristics of infective endocarditis (IE) post-transcatheter aortic valve replacement (TAVR) according to transcatheter valve type. We aimed to determine the incidence, clinical characteristics, and outcomes of patients with IE post-TAVR treated with balloon-expandable valve (BEV) versus self-expanding valve (SEV) systems.

METHODS

Data from the multicenter Infectious Endocarditis After TAVR International Registry was used to compare IE patients with BEV versus SEV.

RESULTS

A total of 245 patients with IE post-TAVR were included (SEV, 47%; BEV, 53%). The timing between TAVR and IE was similar between groups (SEV, 5.5 [1.2-15] months versus BEV, 5.3 [1.7-11.4] months; P=0.89). Enterococcal IE was more frequent in the SEV group (36.5% versus 15.4%; P<0.01), and vegetation location differed according to valve type (stent frame, SEV, 18.6%; BEV, 6.9%; P=0.01; valve leaflet, SEV, 23.9%; BEV, 38.5%; P=0.01). BEV recipients had a higher rate of stroke/systemic embolism (20.0% versus 8.7%, adjusted OR: 2.46, 95% CI: 1.04-5.82, P=0.04). Surgical explant of the transcatheter valve (SEV, 8.7%; BEV, 13.8%; P=0.21), and in-hospital death at the time of IE episode (SEV, 35.6%; BEV, 37.7%; P=0.74) were similar between groups. After a mean follow-up of 13±12 months, 59.1% and 54.6% of the SEV and BEV recipients, respectively, had died (P=0.66).

CONCLUSIONS

The characteristics of IE post-TAVR, including microorganism type, vegetation location, and embolic complications but not early or late mortality, differed according to valve type. These results may help to guide the diagnosis and management of IE and inform future research studies in the field.

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.

Prosthetic valve endocarditis - A trouble or a challenge?

Prosthetic valve endocarditis (PVE) represents a rare and serious complication of valve replacement associated with high morbidity and mortality, which significantly differs from native valve endocarditis (NVE). There are two major problems: establishing diagnosis and treatment of PVE. Diagnosis in PVE is challenging and often requires several imaging methods besides standard microbiological analyzes. Transesophageal echocardiographic examination remains the widely used imaging technique in PVE diagnosis, but additional techniques such as computed tomography (CT) and ¹⁸F-fluodeoxyglucose positron emission tomography/CT are often necessary. Persistent fever, embolic complications, valve dehiscence, intracardial abscess, heart failure, as well as staphylococcal and fungal PVE require surgical treatment to avoid lethal outcome. The introduction of transcatheter valve implantations and devices significantly complicated the approach - diagnostic and therapeutic to PVE patients. Despite constantly increasing knowledge regarding pathogenesis and treatment of PVE, the optimal therapy remains a matter of debate. Additional studies are necessary to define therapeutic strategies for this potentially fatal complication.

Outcomes of Reoperative Valve Replacement in Patients with Prosthetic Valve Endocarditis: A 20-Year Experience

Background

Prosthetic valve endocarditis (PVE) is a serious complication of cardiac valve replacement, and many patients with PVE require reoperation. The aim of this study was to review our institutional 20-year experience of surgical reoperative valve replacement in patients with PVE.

Methods

A retrospective study was performed on 84 patients (mean age, 54.8±12.7 years; 51 males) who were diagnosed with PVE and underwent reoperative valve replacement from January 1995 to December 2016.

Results

PVE was found in 1 valve in 61 cases (72.6%), and in 2 or more valves in 23 cases (27.4%). The median follow-up duration was 47.3 months (range, 0 to 250 months). Postoperative complications occurred in 39 patients (46.4%). Reinfection occurred in 6 cases, all within 1 year. The freedom from reinfection rate at 5 years was 91.0%±3.5%. The overall survival rates at 5 and 10 years were 64.4%±5.8% and 54.3%±7.3%, respectively. In stepwise multivariable Cox proportional hazard models, older age (hazard ratio [HR], 1.48; 95% confidence interval [CI], 1.05 to 2.10; p=0.027) and cardiopulmonary bypass (CPB) time (HR, 1.03; 95% CI, 1.00 to 1.01; p=0.033) emerged as independent risk factors for death.

Conclusion

Older age and a longer CPB time were associated with an increased risk of overall mortality in PVE patients.

Three-Dimensional Echocardiography for Diagnosis of Transcatheter Prosthetic Aortic Valve Endocarditis

• Three-dimensional TEE adds value in diagnosing IE in bioprosthetic valves. • Bioprosthetic valve IE resolves with appropriate antibiotic therapy. • Misdiagnosis of IE can lead to inappropriate treatment and lethal complications.

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.

Valve selection in aortic valve endocarditis

Aortic prosthetic valve endocarditis (PVE) is a potentially life-threatening disease. Mortality and incidence of infective endocarditis have been reduced in the past 30 years. Medical treatment of aortic PVE may be successful in patients who have a prompt response after antibiotic treatment and who do not have prosthetic dysfunction. In advanced stages, antibiotic therapy alone is insufficient to control the disease, and surgical intervention is necessary. Surgical treatment may be lifesaving, but it is still associated with considerable morbidity and mortality. The aim of surgery is to perform a radical excision of all infected and necrotic tissue, reconstruction of the left ventricle outflow tract, and replacement of the aortic valve. There is no unanimous consensus on which is the optimal prosthesis to implant in this context, and several surgical techniques have been suggested. We aim to analyze the efficacy of the surgical treatment and discuss the issue of valve selection in patients with aortic valve endocarditis.

Over 20 years experience with aortic homograft in aortic valve replacement during acute infective endocarditis

OBJECTIVES

Despite the controversy, the aortic homograft is supposedly the best option in acute infective endocarditis (AIE), due to its resistance to reinfection. However, the technical complexity and the risk of structural deterioration over time have limited its utilization. The aim of this study was to evaluate the long-term results of aortic homograft for the treatment of infective endocarditis in our institution with particular attention to predictors of survival and homograft reoperation.

METHODS

The cohort includes 112 patients who underwent aortic valve replacement with an aortic homograft for AIE between January 1990 and December 2014.

RESULTS

Fifteen patients (13.4%) died during the first 30 days after the operation. Two patients were lost to follow-up after discharge from the hospital; therefore, 95 patients were available for long-term analysis. The median duration of follow-up was 7.8 years (IQR 4.7-17.6). Five patients (5.3%) suffered a recurrence of infective endocarditis (1 relapse and 4 new episodes). Sixteen patients (16.8%) were reoperated for structural valve degeneration (SVD; n = 14, 87.5%) or for infection recurrence (n = 2, 12.5%). Freedom from homograft reoperation for infective endocarditis or structural homograft degeneration at 10 and 15 years postoperatively was 86.3 ± 5.5 and 47.3 ± 11.0%, respectively. For patients requiring homograft reoperation, the median interval to reintervention was 11.6 years (IQR 8.3-14.5). Long-term survival was 63.6% (95% CI 52.4-72.8%) and 53.8% (95% CI 40.6-65.3%) at 10 and 15 years, respectively.

CONCLUSIONS

The use of aortic homograft in acute aortic valve endocarditis is associated with a remarkably low risk of relapsing infection and very acceptable long-term survival. The risk of reoperation due to SVD is significant after one decade especially in young patients. The aortic homograft seems to be ideally suited for reconstruction of the aortic valve and cardiac structures damaged by the infective process especially in early surgery.

Surgery for prosthetic valve endocarditis: associations between morbidity, mortality and costs

OBJECTIVES

Surgery for prosthetic valve endocarditis (PVE) is associated with significant morbidity and mortality as well as with increased resource utilization and costs. For risk and cost reduction, an understanding of contributing factors and interrelations is essential.

METHODS

Out of 1080 heart valve procedures performed between January 2010 and December 2012, 41 patients underwent surgery for PVE. Complete economic data were available for 30 of them (study cohort). The patients' mean age was 64 ± 12 years (range 37-79 years), and 73% were men. The clinical course was reviewed and morbidity, mortality and costs as well as associations between them were analysed. The cost matrix for each individual patient was obtained from the Institute for the Hospital Remuneration System (InEK GmbH, Germany). The median follow-up was 2.6 years [interquartile range (IQR) 3.7 years; 100% complete].

RESULTS

Preoperative status was critical (EuroSCORE II >20%) in 43% of patients. Staphylococci were the most common infecting micro-organisms (27%). The operative mortality rate (≤30 days) was 17%. At 1 year, the overall survival rate was 71 ± 9%. At least one disease- or surgery-related complication affected 21 patients (early morbidity 70%), >1 complication affected 12 patients (40%). There was neither a recurrence of endocarditis, nor was a reoperation required. The mean total hospital costs were 42.6 ± 37.4 Thousand Euro (T€), median 25.7 T€, IQR 28.4 T€ and >100 T€ in 10% of cases. Intensive care unit/intermediate care (ICU/IMC) and operation accounted for 40.4 ± 18.6 and 25.7 ± 12.1% of costs, respectively. There was a significant correlation (Pearson's sample correlation coefficient) between total costs and duration of hospital stay (r = 0.83, P < 0.001) and between ICU/IMC costs and duration of ICU/IMC stay (r = 0.97, P < 0.001). The median daily hospital costs were 1.8 T€/day, but >2.4 T€/day in 25% of patients (upper quartile). The following pattern of associations was identified (P < 0.05). Early mortality was related to preoperative morbidity and postoperative renal failure. Early morbidity was associated with preoperative morbidity and urgency. Total costs were mainly explained by preoperative morbidity, postoperative morbidity and urgency. High EuroSCORE II, complex surgery, need for mechanical circulatory support as well as postoperative mortality and morbidity increased daily costs.

CONCLUSIONS

The timely diagnosis and treatment of these patients must be a priority, as preoperative morbidity is the major contributor towards mortality, morbidity and costs after surgery for PVE.

Surgical Treatment of Aortic Prosthetic Valve Endocarditis: A 20-Year Single-Center Experience

BACKGROUND

Despite progress in diagnostic methods and treatment, aortic prosthetic valve endocarditis (PVE) remains a life-threatening disease. We report the outcome of all operations for aortic PVE performed at our institution over the past 20 years.

METHODS

Eighty-seven operations performed in 84 patients between 1993 and 2013 were included in this retrospective study. An aortic homograft was used in 56 (64%) cases, a mechanical prosthesis was used in 20 (23%) cases, and a bioprosthesis was used in 11 (13%) cases. Early and late complications and mortality were compared between the first and second decades of our experience. Predictors of mortality were identified with Cox regression. Mean follow-up was 5.5 years (range 0-17 years).

RESULTS

Nine patients (10%) died within 30 days, and severe perioperative complications occurred in 36 patients (41%). Overall cumulative survival was 80% at 5 years and 65% at 10 years. Four (12.9%) of the patients treated with mechanical or biological prostheses had a recurrent episode of endocarditis, compared with none of the patients treated with homografts (p = 0.006). During the second decade, 30-day mortality was lower (3.6% versus 22%; p = 0.007) and 5-year cumulative survival was higher (88% versus 66%; p = 0.027). Age, preoperative serum creatinine, and severe perioperative complications were independent predictors of mortality during follow-up.

CONCLUSIONS

Aortic PVE is associated with a high rate of early complications and substantial early mortality. Patients who survive the immediate postoperative period have satisfactory long-term survival. The risk of recurrent endocarditis is low, especially in patients treated with homografts. The results have improved during the past decade.

Combined computed tomography and fluorodeoxyglucose positron emission tomography in the diagnosis of prosthetic valve endocarditis: a case series

Background

The diagnosis of prosthetic valve endocarditis is challenging. The gold standard for prosthetic valve endocarditis diagnosis is trans-esophageal echocardiography. However, trans-esophageal echocardiography may result in negative findings or yield images difficult to differentiate from thrombus in patients with prosthetic valve endocarditis. Combined computed tomography and fluorodeoxyglucose positron emission tomography is a potentially promising diagnostic tool for several infectious conditions and it has also been employed in patients with prosthetic valve endocarditis but data are still scant.

Case presentations

We reviewed the charts of 6 patients with prosthetic aortic valves evaluated for suspicion of prosthetic valve endocarditis, at two different hospital, over a 3-year period. We found 3 patients with early-onset PVE cases and blood cultures yielding Pseudomonas aeruginosa, Staphylococcus epidermidis and Staphylococcus lugdunensis, respectively; and 3 late-onset cases in the remaining 3 patients with isolation in the blood of Streptococcus bovis, Candida albicans and P. aeruginosa, respectively. Initial trans-esophageal echocardiography was negative in all the patients, while fluorodeoxyglucose positron emission tomography showed images suspicious for prosthetic valve endocarditis. In 4 out of 6 patients valve replacement was done with histology confirming the prosthetic valve endocarditis diagnosis. After an adequate course of antibiotic therapy fluorodeoxyglucose positron emission tomography showed resolution of prosthetic valve endocarditis in all the patients.

Conclusion

Our experience confirms the potential role of fluoroseoxyglucose positron emission tomography in the diagnosis and follow-up of prosthetic valve endocarditis.

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.

Clinical significance of congestive heart failure in prosthetic valve endocarditis. A multicenter study with 257 patients

INTRODUCTION AND OBJECTIVES

There have been no studies conducted in the past that focus on the significance of congestive heart failure in patients with prosthetic valve endocarditis. We studied the incidence of congestive heart failure in patients with prosthetic valve endocarditis and analyzed its profile. In this study, we addressed the prognostic significance of heart failure in patients with prosthetic valve endocarditis and analyzed its outcome based on chosen therapeutic strategies.

METHODS

A total of 639 episodes of definite left-sided endocarditis were prospectively enrolled. Of them, 257 were prosthetic. Of the 257 episodes, 145 (56%) were diagnosed with heart failure. We compared the profiles of patients with prosthetic valve endocarditis based on the presence of heart failure, and performed a multivariate logistic regression model to establish the prognostic significance of heart failure in patients with prosthetic valve endocarditis and identified the prognostic factors of in-hospital mortality in these patients.

RESULTS

Persistent infection (odds ratio=3.6; 95% confidence interval, 1.9-6.9) and heart failure (odds ratio=3; 95% confidence interval, 1.5-5.8) are the strongest predictive factors of in-hospital mortality in patients with prosthetic valve endocarditis. The short-term determinants of prognosis in patients with prosthetic valve endocarditis and heart failure are persistent infection (odds ratio=2.8; 95% confidence interval, 1.2-6.5), aortic involvement (odds ratio=2.5; 95% confidence interval, 1.1-5.8), abscess (odds ratio=3.6; 95% confidence interval, 1.4-9.5), diabetes mellitus (odds ratio=2.9; 95% confidence interval, 1.1-7.7), and cardiac surgery (odds ratio=0.2; 95% confidence interval, 0.1-0.5).

CONCLUSIONS

The incidence of heart failure in patients with prosthetic valve endocarditis is very high. Heart failure increases the risk of in-hospital mortality by threefold in patients with prosthetic valve endocarditis. Persistent infection, aortic involvement, abscess, and diabetes mellitus are the independent risk factors associated with mortality in patients with prosthetic valve endocarditis and heart failure; however, cardiac surgery is shown to decrease mortality in these patients.

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.).

Mycobacterial prosthetic valve endocarditis

Prosthetic valve endocarditis (PVE) due to mycobacteria is a rare but frequently fatal complication that may occur early after the surgical procedure, or even years later. Infection has been described with both mechanical and biologic valvular prosthesis. The most commonly implicated mycobacterial species belong to the rapid-grower group (M. chelonei, M. fortuitum, and M. abscessus) of nontuberculous mycobacteria (NTM). The source of infection in this context is thought to be nosocomial, likely related to preoperative or intraoperative contamination of the prosthesis by contact with aqueous solutions containing the organisms. These infections are difficult to diagnose because blood cultures are often negative. Clinically, it is important to recognize the possibility of NTM-PVE in the differential diagnosis of culture-negative patients who develop signs and symptoms of endocarditis, whether they present early or late in onset after the surgical procedure. These patients should be treated with surgical removal of the infected valve, followed by adequate antimicrobial therapy based on the susceptibility of the species isolated from the valve or perivalvular tissue culture. In a significant number of patients, however, an unstable hemodynamic condition ensues, precluding surgical intervention, and therefore leading to a high mortality rate.

Management of neurological complications of infective endocarditis in ICU patients

Patients with infective endocarditis (IE) are generally referred to the intensive care unit (ICU) for one or more organ dysfunctions caused by complications of IE. Neurologic events are frequent causes of ICU admission in patients with IE. They can arise through various mechanisms consisting of stroke or transient ischemic attack, cerebral hemorrhage, mycotic aneurysm, meningitis, cerebral abscess, or encephalopathy. Most complications occur early during the course of IE and are a hallmark of left-sided abnormalities of native or prosthetic valves. Occlusion of cerebral arteries, with stroke or transient ischemic attack, accounts for 40% to 50% of the central nervous system complications of IE. CT scan is the most easily feasible neuroimaging in critically unstable patients. However, magnetic resonance imaging is more sensitive and when performed should follow a standardized protocol. In patients with ischemic stroke who are already receiving oral anticoagulant therapy, this treatment should be replaced by unfractionated heparin for at least 2 weeks with a close monitoring of coagulation tests. Mounting evidence shows that, for both complicated left-sided native valve endocarditis and Staphylococcus aureus prosthetic valve endocarditis, valve replacement combined with medical therapy is associated with a better outcome than medical treatment alone. In a recent series, approximately 50% of patients underwent valve replacement during the acute phase of IE before completion of antibiotic treatment. After a neurological event, most patients have at least one indication for cardiac surgery. Recent data from literature suggest that after a stroke, surgery indicated for heart failure, uncontrolled infection, abscess, or persisting high emboli risk should not be delayed, provided that the patient is not comatose or has no severe deficit. Neurologic complications of IE contribute to a severe prognosis in ICU patients. However, patients with only silent or transient stroke had a better prognosis than patients with symptomatic events. In addition, more than neurologic event per se, a better predictor of mortality is neurologic dysfunction, which is associated with location and extension of brain damage. Patients with severe neurological impairment and those with brain hemorrhage have the worse outcome.

Surgery in current therapy for infective endocarditis

The introduction of the Duke criteria and transesophageal echocardiography has improved early recognition of infective endocarditis but patients are still at high risk for severe morbidity or death. Whether an exclusively antibiotic regimen is superior to surgical intervention is subject to ongoing debate. Current guidelines indicate when surgery is the preferred treatment, but decisions are often based on physician preferences. Surgery has shown to decrease the risk of short-term mortality in patients who present with specific symptoms or microorganisms; nevertheless even then it often remains unclear when surgery should be performed. In this review we i) systematically reviewed the current literature comparing medical to surgical therapy to evaluate if surgery is the preferred option, ii) performed a meta-analysis of studies reporting propensity matched analyses, and iii), briefly summarized the current indications for surgery.

Increasing incidence and mortality of infective endocarditis: a population-based study through a record-linkage system

Background

Few population-based studies provide epidemiological data on infective endocarditis (IE). Aim of the study is to analyze incidence and outcomes of IE in the Veneto Region (North-Eastern Italy).

Methods

Residents with a first hospitalization for IE in 2000-2008 were extracted from discharge data and linked to mortality records to estimate 365-days survival. Etiology was retrieved in subsets of this cohort by discharge codes and by linkage to a microbiological database. Risk factors for mortality were assessed through logistic regression.

Results

1,863 subjects were hospitalized for IE, with a corresponding crude rate of 4.4 per 100,000 person-years, increasing from 4.1 in 2000-2002 to 4.9 in 2006-2008 (p = 0.003). Median age was 68 years; 39% of subjects were hospitalized in the three preceding months. 23% of patients underwent a cardiac valve procedure in the index admission or in the following year. Inhospital mortality was 14% (19% including hospital transfers); 90-days and 365-days mortality rose through the study years. Mortality increased with age and the Charlson comorbidity index, in subjects with previous hospitalizations for heart failure, and (in the subcohort with microbiological data) in IE due to Staphylococci (40% of IE).

Conclusions

The study demonstrates an increasing incidence and mortality for IE over the last decade. Analyses of electronic archives provide a region-wide picture of IE, overcoming referral biases affecting single clinic or multicentric studies, and therefore represent a first fundamental step to detect critical issues related to IE.

Prosthetic valve endocarditis

Prosthetic valve endocarditis (PVE) is associated with a high mortality during the early and midterm follow-up despite diagnostic and therapeutic improvements; its incidence is increasing and reaches 20-30% of all infective endocarditis episodes. In this review, changes in epidemiology, microbiology, diagnosis and therapy that have evolved in the past few years are analyzed. Staphylococci (both Staphylococcus aureus and coagulase-negative Staphylococcus) have emerged as the most common cause of PVE and are associated with a severe prognosis. Moreover, diagnosis may often be difficult because of its complications and extracardiac manifestations; thus, a comprehensive assessment of the clinical, echocardiographic and laboratory data must be performed. Early PVE, comorbidity, severe heart failure and new prosthetic dehiscence are predictors of mortality. Therapy is not indicated by evidence-based recommendations but mostly on identification of the high-risk conditions. A PVE is a common indication for surgery, whereas medical treatment alone may be achieved in a few instances. Systematic prophylaxis should be used to prevent this severe complication of cardiac valve replacement.

Redo aortic valve surgery: Influence of prosthetic valve endocarditis on outcomes

OBJECTIVE

Compared with reoperative aortic valve replacement for nonendocarditic causes, the contemporary risk and long-term outcomes of reoperation for aortic prosthetic valve endocarditis are ill-defined.

METHODS

Between December 1994 and April 2008, 313 patients underwent reoperative aortic valve replacement, of whom 152 (48.6%) had prosthetic valve endocarditis. Mean follow-up was 6.5 ± 0.4 years and 97.4% complete.

RESULTS

Patients with prosthetic valve endocarditis were older with a higher risk profile. The overall hospital mortality was 15.3% (n = 48) (prosthetic valve endocarditis vs nonendocarditis: 24.3%, n = 37, vs 6.8%, n = 11; P < .001). Independent predictors of perioperative mortality for prosthetic valve endocarditis were sepsis (odds ratio [OR], 6.5; 95% confidence interval [CI], 2.0-21.0; P < .01), ejection fraction less than 30% (OR, 5.8; 95% CI, 1.3-25.0; P = .02), concomitant coronary artery bypass grafting (OR, 3.3; 95% CI, 1.1-9.8; P = .03), and aortic root abscess (OR, 2.7; 95% CI, 1.2-6.4; P = .02), and for the nonendocarditis group were concomitant coronary artery bypass grafting (OR, 8.1; 95% CI, 2.0-33.0; P < .01), and mitral valve surgery (OR, 4.8; 95% CI, 1.3-17.9; P = .02). The 1-, 3-, 5-, and 10-year survivals for patients with and without prosthetic valve endocarditis were 52% ± 4% versus 82% ± 3%, 43% ± 5% versus 73% ± 4%, 37% ± 5% versus 63% ± 5%, and 31% ± 7% versus 56% ± 8%, respectively (log rank < 0.001). Predictors of long-term mortality in prosthetic valve endocarditis were sepsis (OR, 3.1; 95% CI, 1.5-4.5; P < .01) and unstable preoperative status (OR, 1.8; 95% CI, 1.2-3.5; P = .04), whereas in nonendocarditis patients the only predictor was New York Heart Association class IV (OR, 2.5; 95% CI, 2.8-7.4; P < .01). Five-year actuarial freedom from endocarditis was 80% ± 0.3% versus 95% ± 0.6% (prosthetic valve endocarditis cersus nonendocarditis; P = .002).

CONCLUSIONS

Despite contemporary therapy, reoperation for aortic prosthetic valve endocarditis is still associated with relatively high perioperative mortality and limited long-term survival.

Prosthetic Valve Endocarditis in a Multicenter Registry of Chinese Patients

We evaluated the clinical outcomes of prosthetic valve endocarditis in 2 major tertiary referral centers in Hong Kong. The study population comprised 80 consecutive Chinese patients who fulfilled the modified Duke criteria for prosthetic valve endocarditis from March 2000 to June 2007. The major clinical endpoints analyzed were hospital mortality, need for valve surgery, and relapse of prosthetic endocarditis. The mean age at presentation was 56 ± 13 years, with a slight male preponderance. There were 76 (95%) patients with involvement of a mechanical prosthesis; the majority (69%) had late prosthetic endocarditis. Major hospital complications occurred in 49 (61%) patients. The overall hospital mortality was 28% (22 patients). Thirty-four (42%) patients required valve surgery during index hospitalization, of whom 5 (15%) died due to uncontrolled sepsis. Factors associated with hospital mortality were older age at presentation, Staphylococcus aureus infection, embolic events, severe heart failure, valve surgery, and any major complication. On multivariate analysis, severe heart failure was the only independent predictor of hospital death. Among the 58 hospital survivors followed up for a mean of 48 ± 31 months, 6 (10%) developed late complications related to prosthetic valve endocarditis, with 5 documented cases of relapse.

The changing face of prosthetic valve endocarditis at a tertiary-care hospital: 1986-2005

INTRODUCTION AND OBJECTIVES

To investigate changes in the clinical characteristics, etiology and prognosis of prosthetic valve endocarditis at a tertiary-care hospital.

METHODS

Retrospective cohort study of all patients diagnosed with prosthetic valve endocarditis using modified Duke criteria between 1986 and 2005. The analysis covered two time periods: January 1986 to December 1995 (P1) and January 1996 to December 2005 (P2).

RESULTS

In total, 133 episodes of endocarditis occurred in 122 patients. Of these, 73 (54.9%) were diagnosed in P1 and 60 (45.1%) in P2, with incidences of 2.19% and 2.18%, respectively. The patients' mean age (SD) was 52.6+/-16.6 years in P1 and 66.2+/-11.5 years in P2 (P=.0001). Clinical characteristics were similar in the two study periods. The increase in Enterococcus infection was remarkable (12.5% in P2 vs. 4.9% in P1; relative risk [RR]=2.5; 95% confidence interval [CI], 0.7-9.6), as was the decrease in viridans group Streptococcus infection (12.5% in P2 vs. 31.1% in P1; RR=0.4; 95% CI, 0.2-0.9). Some 90.4% of patients (63/73) underwent surgery in P1, while 68.3% (41/60) underwent surgery in P2. The difference was significant (RR=0.8; 95% CI, 0.6-0.9). The in-hospital mortality rate was 28.8% in P1 and 30% in P2 (RR=1; 95% CI, 0.6-1.7).

CONCLUSIONS

Changes in the epidemiology and microbiological etiology of prosthetic valve endocarditis were observed over the 20-year study period. Diagnostic and therapeutic approaches also changed, but mortality remained high.

In-hospital prognosis of prosthetic valve endocarditis after urgent surgery

INTRODUCTION AND OBJECTIVES

Prosthetic valve endocarditis is associated with high morbidity and mortality, particularly when urgent surgery is needed. The identification of factors that predict a poor prognosis is the first step in improving outcomes. The study objectives were to characterize patients with prosthetic valve endocarditis who need urgent surgery and to identify factors that predict in-hospital mortality in this high-risk group.

METHODS

From a database of 648 consecutive patients with infective endocarditis diagnosed between 1996 and 2006 at four tertiary-care centers with cardiac surgery facilities, 46 patients with left-sided prosthetic valve endocarditis who needed urgent surgery were identified. A retrospective study was carried out to determine these patients' main characteristics and to identify predictors of in-hospital mortality.

RESULTS

The main indications for urgent surgery were heart failure (57%) and persistent infection (33%). In-hospital mortality was 41%. Factors significantly associated with a poor prognosis were fever at admission, persistent infection, positive blood cultures, persistently positive cultures, and echocardiographic evidence of vegetations (P< .05). No specific microorganism was associated with a poor prognosis.

CONCLUSIONS

Prosthetic valve endocarditis was associated with high mortality when urgent surgery was needed. Although heart failure was the principle reason for urgent surgery, it did not lead to a worse in-hospital prognosis. The presence of vegetations and uncontrolled infection were the main factors associated with higher in-hospital mortality in patients with left-sided infective endocarditis who needed urgent surgery.

Acute infective endocarditis

Acute infective endocarditis is a complex disease with changing epidemiology and a rapidly evolving knowledge base. To consistently achieve optimal outcomes in the management of infective endocarditis, the clinical team must have an understanding of the epidemiology, microbiology, and natural history of infective endocarditis, as well as a grasp of guiding principles of diagnosis and medical and surgical management. The focus of this review is acute infective endocarditis, though many studies of diagnosis and treatment do not differentiate between acute and subacute disease, and indeed many principles of diagnosis and management of infective endocarditis for acute and subacute disease are identical.

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.

[Case of infective endocarditis diagnosed with renal infarction]

A 46-year-old woman with sudden on set strong right flank pain was transferred to our hospital with the diagnosis of right renal infarction. Cardiac ultrasonography revealed a vegetation on the posterior cusp of the mitral valve, and the renal infarction was thought to be caused by renal artery embolism from infective endocarditis. Since the vegetation remained after antimicrobial therapy as conservative management, the patient was surgically treated by mitral annuloplasty. It has been known that infective endocarditis can cause renal infarction. Infective endocarditis requires immediate and adequate treatment because of high mortality. Therefore, the appropriate diagnosis of infective endocarditis is needed for patients with renal infarction without any other disorder causing renal infarction.

Rationale, design, and methods for the early surgery in infective endocarditis study (ENDOVAL 1): a multicenter, prospective, randomized trial comparing the state-of-the-art therapeutic strategy versus early surgery strategy in infective endocarditis

BACKGROUND

The prognosis of infective endocarditis is poor and has remained steady over the last 4 decades. Several nonrandomized studies suggest that early surgery could improve prognosis.

METHODS

ENDOVAL 1 is a multicenter, prospective, randomized study designed to compare the state-of-the-art therapeutic strategy (advised by the international societies in their guidelines) with the early-surgery strategy in high-risk patients with infective endocarditis. Patients with infective endocarditis without indication for surgery will be included if they meet at least one of the following: (1) early-onset prosthetic endocarditis; (2) Staphylococcus aureus endocarditis; (3) periannular complications; (4) new-onset conduction abnormalities; (5) new-onset severe valvular dysfunction. A total of 216 patients will be randomized to either of the 2 strategies. Stratification will be done within 3 days of admission. In the early surgery arm, the surgical procedure will be performed within 48 hours of randomization. The only event to be considered will be death within 30 days. The study will be extended to 1 year. In the follow-up substudy, death and a new episode of endocarditis will be regarded as events.

CONCLUSION

ENDOVAL 1, the first randomized study on endocarditis, will provide crucial information regarding the putative benefit of early surgery over the state-of-the-art therapeutic approach in high-risk patients with infective endocarditis.

Endocarditis due to Listeria: description of two cases and review of the literature

Endocarditis due to Listeria monocytogenes is a very uncommon and very serious disease that may lead to valve dysfunction and cardiac arrest. We report two cases of endocarditis caused by L. monocytogenes and review the papers previously published on the subject.

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.

Infective endocarditis: outcome in surviving patients with intracardiac complications

OBJECTIVE

The purpose of this study was to assess the outcome of 15 patients who survived infective endocarditis with abscesses and other intracardiac complications.

METHODS

Abscesses were associated with native valve endocarditis in seven patients and prosthetic valve endocarditis in eight patients; fistulas were observed in three patients, and subaortic perforation in three patients. Sensitivity for the detection of abscesses was 42.8% and 92.8% using transthoracic and transoesophageal echocardiography, respectively. Eleven patients underwent surgical treatment with no operative mortality, whereas four patients were only medically treated.

RESULTS

During follow-up (mean 8.26 years), two patients died (13%) and six recurrences (five early and one late prosthetic valve endocarditis) required re-intervention for prosthesis dysfunction (40%); an improvement in New York Heart Association class in survivors and no changes in echocardiographic lesions were observed.

CONCLUSIONS

Infective intracardiac complications do not seem to significantly reduce the overall survival (87%) of patients at long-term follow-up.

Aortic valve endocarditis: is there an optimal surgical timing?

PURPOSE OF REVIEW

Patients with aortic valve infective endocarditis are likely to undergo surgery during the active phase of the disease. The indication and best timing for surgery, however, are still debated. The present review discusses the benefits and risks of early surgery in aortic endocarditis.

RECENT FINDINGS

Patients with acute aortic regurgitation and clinical or echocardiographic signs of poor tolerance require urgent surgery. Other indications for early surgery include severe perivalvular involvement and high embolic risk. Echocardiography plays an important role in the assessment of embolic risk and helps in choosing the best therapeutic strategy. Several recent studies have identified high-risk subgroups of patients that, without surgery, face poor prognosis. Patients with complicated endocarditis, particularly those with congestive heart failure, will benefit most from surgery. Patients with prosthetic valve endocarditis and cerebral complications represent specific subgroups in which surgical decision is more difficult.

SUMMARY

Patients with severe aortic leaflet destruction and congestive heart failure, patients with perivalvular extension or uncontrolled infection, and patients with high embolic risk have poor outcome under medical therapy. Early surgery is necessary in all such patients with 'complicated' endocarditis, unless severe comorbidity is present.