Indications for cardiac surgery in patients with active infective endocarditis

Post-operative infections after cardiothoracic surgery and vascular procedures: a bibliometric and visual analysis of the 100 most-cited articles in the past 2 decades

Aim

To recognize and analyze the 100 most-cited articles on post-operative infections following cardiothoracic surgery and vascular procedures in the past 20 years.

Methods

Articles published on post-operative infections following cardiothoracic surgery and vascular procedures from inception 1986 till 2020 were reviewed and selected by two authors, based on their number of citations using the Scopus database. Their characteristics were recorded, i.e., title, authors, publication date, total no. of citations, citations per year (CPY), country of research, institutional affiliation, journal, research subject, and article type.

Results

The top 100 most influential articles were published between 1968 and 2017, with the peak in 2002. The mean number of total citations was 236.79 (range: 108-1,157). Areas with a medical focus were predominant in the studied research articles on the researched topic. The top-most journals in which these articles were published include Annals of Thoracic Surgery (14), followed by Circulation (8), and the New England Journal of Medicine (8). The number of publications affiliated with an institution were highest in the United States, with the Cleveland Clinic Foundation (6) having the most.

Conclusion

These findings highlight that there is a great potential to conduct research and publish the prevalence, causes, risk factors, pathogenesis and molecular biology of post-cardiac and -vascular surgery infections to prevent their adverse effects. The results can be taken into consideration for policy making to improve post-cardiac-surgery outcomes.

Infective endocarditis in an intravenous drug user: multiple fatal complications

Here, we present a case of a 43-year-old patient with a background of active intravenous drug use who was diagnosed with aortic valve endocarditis. This was complicated by extensive acute embolic stroke and acute splenic, renal and liver infarction. This case highlights the difficulties in managing infective endocarditis in intravenous drug users and the importance of a comprehensive approach, addressing both the intracardiac infection and the underlying issue of substance misuse, to ensure best patient outcomes.

A comparison between dexmedetomidine and propofol on extubation times in postoperative adult cardiac surgery patients: a systematic review protocol

REVIEW QUESTION/OBJECTIVE

The objective of this systematic review is to synthesize the best available evidence regarding the effects of dexmedetomidine compared to propofol on time to extubation, intensive care unit (ICU) length of stay (LOS), hospital LOS and mortality in postoperative adult cardiac surgery patients.The specific review question is as follows:What is the effectiveness of dexmedetomidine compared to propofol on times to extubation, ICU LOS, hospital LOS and mortality in postoperative adults undergoing cardiac surgery?

Syndromes of Acute Left Ventricular Failure

The syndrome of acute left ventricular failure, manifesting as pulmonary edema and/or cardiogenic shock, occurs in many different clinical settings, has many different causes, and variable treatment strategies. Most commonly it is seen as a complication of acute myocardial infarction where loss of myocardial tissue results in ineffective systolic performance of the left ventricle. Urgent percutaneous transluminal coronary angioplasty may have a significant impact on outcome in this setting. Other complicating events following myocardial infarction may also precipitate left ventricular failure including papillary muscle dysfunction and ventricular septal defect. The syndrome of acute left ventricular failure is also commonly seen in patients with chronic congestive cardiac failure whereby myocardial infarction, arrhythmia and even minor increases in salt intake can precipitate acute decompensation. Other conditions such as fulminant myocarditis, bacterial endocarditis and disease processes characterized by diastolic dysfunction can all cause acute left ventricular failure. Moreover, cardiac function may be depressed in septic shock by the presence of cardiodepressant factors. In summary, acute left ventricular failure is a syndrome with a diverse etiology. Specific diagnosis of the particular cause is crucial to appropriate management.

Infective Endocarditis in Adults: Diagnosis, Antimicrobial Therapy, and Management of Complications: A Scientific Statement for Healthcare Professionals From the American Heart Association

BACKGROUND

Infective endocarditis is a potentially lethal disease that has undergone major changes in both host and pathogen. The epidemiology of infective endocarditis has become more complex with today's myriad healthcare-associated factors that predispose to infection. Moreover, changes in pathogen prevalence, in particular a more common staphylococcal origin, have affected outcomes, which have not improved despite medical and surgical advances.

METHODS AND RESULTS

This statement updates the 2005 iteration, both of which were developed by the American Heart Association under the auspices of the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease of the Young. It includes an evidence-based system for diagnostic and treatment recommendations used by the American College of Cardiology and the American Heart Association for treatment recommendations.

CONCLUSIONS

Infective endocarditis is a complex disease, and patients with this disease generally require management by a team of physicians and allied health providers with a variety of areas of expertise. The recommendations provided in this document are intended to assist in the management of this uncommon but potentially deadly infection. The clinical variability and complexity in infective endocarditis, however, dictate that these recommendations be used to support and not supplant decisions in individual patient management.

Current diagnosis and treatment of infective endocarditis

The incidence of infective endocarditis continues to rise with a yearly incidence of around 15,000 to 20,000 new cases in the USA. As a result, rapid diagnosis, effective treatment and prompt recognition of complications are essential to desirable clinical outcomes. Recent guidelines such as the Duke criteria have incorporated echocardiography for diagnosis of infective endocarditis, making this diagnostic test mandatory for patients with suspected infective endocarditis. The diversity of pathogens that can cause infective endocarditis, some of which cannot be cultured easily, makes diagnosis even more difficult. Coagulase-negative staphylococci and viridans streptococci groups continue to be the major causative microorganisms of infective endocarditis. In the case of culture-negative endocarditis or infective endocarditis caused by fastidious microorganisms, the polymerase chain reaction and probe-based diagnostic methods are available to clinical reference laboratories.

Japanese features of native valve endocarditis caused by coagulase-negative staphylococci: case reports and a literature review

Although coagulase-negative staphylococci (CoNS) is a frequent cause of prosthetic valve endocarditis, native valve endocarditis (NVE) caused by CoNS is not commonly seen. Its high mortality is well known; however, there are no systematic reports published in Japan. We herein report the cases of two Japanese patients with CoNS NVE who were admitted to our hospital located in Tokyo and conduct literature searches on CoNS NVE in Japan from 1983 to March 2012 using PubMed and ICHUSHI WEB (Japan Medical Abstract Society). We also summarize the features of 22 Japanese patients with CoNS NVE, including our patients.

Valvular perforation in left-sided native valve infective endocarditis

BACKGROUND

Left-sided native valve infective endocarditis (LNVIE) can result in mitral (MP) and aortic (AP) valve perforation, the prognostic significance of which remains poorly defined.

HYPOTHESIS

Valvular perforation is associated with worse outcomes.

METHODS

Retrospective review of patients with LNVIE during 1998-2005 was performed to examine characteristics and outcome predictors of LNVIE complicated by valve perforation. Patients were stratified as: group A: MP or AP detected by transesophageal echocardiography (TEE) or surgery; group B: no TEE evidence of MP or AP.

RESULTS

A total of 123 patients were included (group A = 47, group B = 76). In group A, 35 patients (74.5%) had MP alone, 11 (23.4%) had AP alone, and 1 patient had both. Severe valvular insufficiency was encountered more in group A (85.1% versus 59.2%, p = 0.003), so was hemodialysis (40.4% versus 17.1%, p = 0.004) and indications for valvular surgery (93.6% versus 77.6%, p = 0.02). Group A had a higher rate of in-hospital death (31.9% versus 15.8%, p = 0.04). Among patients who had an indication for valvular surgery, the in-hospital mortality rate for those who underwent valvular surgery was 16.7% in group A, and 7.9% in group B (p = 0.4), compared to those who did not undergo surgery (71.4% versus 33.3%, p = 0.04). Amongst survivors, hospital stay was on average 9.2 d longer in group A (38.9 versus 29.7 d, p = 0.05). Univariate analysis revealed association between lower survival and valvular perforation (odds ratio [OR]: 0.4, 95% confidence interval [CI]: 0.17-0.95), that was lost after adjusting for hemodialysis.

CONCLUSIONS

Valve perforation complicating LNVIE is associated with hemodialysis, severe valvular insufficiency, and significant morbidity and mortality. Compared to conservative management, early surgical intervention is associated with improved survival.

[Evaluation of the status of patients with severe infection, criteria for intensive care unit admittance. Spanish Society for Infectious Diseases and Clinical Microbiology. Spanish Society of Intensive and Critical Medicine and Coronary Units]

Recent studies have shown that early attention in patients with serious infections is associated with a better outcome. Assistance in intensive care units (ICU) can effectively provide this attention; hence patients should be admitted to the ICU as soon as possible, before clinical deterioration becomes irreversible. The objective of this article is to compile the recommendations for evaluating disease severity in patients with infections and describe the criteria for ICU admission, updating the criteria published 10 years ago. A literature review was carried out, compiling the opinions of experts from the Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC, Spanish Society for Infectious Diseases and Clinical Microbiology) and the Sociedad Española de Medicina Intensiva, Crítica y Unidades Coronarias (SEMICYUC, Spanish Society for Intensive Medicine, Critical Care and Coronary Units) as well as the working groups for infections in critically ill patients (GEIPC-SEIMC and GTEI-SEMICYUC). We describe the specific recommendations for ICU admission related to the most common infections affecting patients, who will potentially benefit from critical care. Assessment of the severity of the patient's condition to enable early intensive care is stressed.

[Timing and indications for surgical intervention in infective endocarditis]

This paper reviews current knowledge on the indications for and timing of cardiac surgery in patients with infective endocarditis. The main indications for surgery are haemodynamic compromise, persisting infection, peripheral embolisation, large size of vegetations, large valvular and paravalvular damage and infections caused by certain microorganisms.

Time-related distribution, risk factors and prognostic influence of embolism in patients with left-sided infective endocarditis

BACKGROUND

Few studies evaluated systemic arterial embolism after beginning of symptoms of infective endocarditis in a large series of patients.

METHODS

We studied 629 patients with left-sided infective endocarditis, aged 37.9+/-17.3 years, 396(63%) men and 233(37%) women. Endocarditis occurred on native valves in 405(64.4%) patients and on prosthetic heart valves in 224(35.6%). Infecting microorganisms were streptococci in 297(47.3%) patients, Staphylococcus aureus in 77(12.3%), Staphylococcus epidermidis in 56(8.9%), enterococci in 51(8.1%), Gram-negative bacteria in 33(5.2%), fungi in 9(1.4%) and other microorganisms in 27(4.2%). In 79(12.6%) patients blood cultures were negative.

RESULTS

146 embolic events occurred in 133(21.1%) out of 629 patients; in 63(47.4%) of them emboli affected the central nervous system, in 57(42.9%) affected peripheral organs and in 13(9.7%) affected both the central nervous system and peripheral organs. Embolism occurred between beginning of symptoms of endocarditis and antimicrobial therapy in 56(42.1%) patients and on the day therapy started in 18(13.5%); 109(81.9%) embolic events occurred up to the 15th day of antimicrobial therapy. Embolic risk was higher in S. aureus endocarditis (relative risk 2.97); in patients with a mitral (relative risk 2.4) or aortic (relative risk 3.3) prosthetic valve and vegetations on echocardiography. Embolic risk was lower in patients with a longer duration of symptoms. The death risk doubled in patients with embolism (relative risk 2.01).

CONCLUSIONS

Embolic events were more frequently early events after beginning of symptoms of infective endocarditis. Embolic risk was higher in S. aureus endocarditis and in patients with prosthetic heart valves and vegetations on echocardiography.

Infective endocarditis: diagnosis, antimicrobial therapy, and management of complications: a statement for healthcare professionals from the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease in the Young, and the Councils on Clinical Cardiology, Stroke, and Cardiovascular Surgery and Anesthesia, American Heart Association: endorsed by the Infectious Diseases Society of America

BACKGROUND

Despite advances in medical, surgical, and critical care interventions, infective endocarditis remains a disease that is associated with considerable morbidity and mortality. The continuing evolution of antimicrobial resistance among common pathogens that cause infective endocarditis creates additional therapeutic issues for physicians to manage in this potentially life-threatening illness.

METHODS AND RESULTS

This work represents the third iteration of an infective endocarditis "treatment" document developed by the American Heart Association under the auspices of the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease of the Young. It updates recommendations for diagnosis, treatment, and management of complications of infective endocarditis. A multidisciplinary committee of experts drafted this document to assist physicians in the evolving care of patients with infective endocarditis in the new millennium. This extensive document is accompanied by an executive summary that covers the key points of the diagnosis, antimicrobial therapy, and management of infective endocarditis. For the first time, an evidence-based scoring system that is used by the American College of Cardiology and the American Heart Association was applied to treatment recommendations. Tables also have been included that provide input on the use of echocardiography during diagnosis and treatment of infective endocarditis, evaluation and treatment of culture-negative endocarditis, and short-term and long-term management of patients during and after completion of antimicrobial treatment. To assist physicians who care for children, pediatric dosing was added to each treatment regimen.

CONCLUSIONS

The recommendations outlined in this update should assist physicians in all aspects of patient care in the diagnosis, medical and surgical treatment, and follow-up of infective endocarditis, as well as management of associated complications. Clinical variability and complexity in infective endocarditis, however, dictate that these guidelines be used to support and not supplant physician-directed decisions in individual patient management.

Active infectious endocarditis: postoperative outcome

OBJECTIVE

Many changes have occurred in the natural history and the management of active infectious endocarditis (AIE) in recent years. Therefore, the records of patients admitted in a tertiary care specialized hospital presenting with the Duke criteria were reviewed.

METHODS

Adults operated on to treat AIE were included during a 3-year period. Patients presenting with AIE associated with a pacemaker were not included. Bacteriologic investigations included blood cultures, intraoperative samplings (including polymerase chain reaction), and serologies. Clinical and bacteriologic factors associated with hospital mortality were studied by univariate regression analysis (p < 0.05).

RESULTS

Ninety-eight of 164 patients (60%) admitted with the diagnosis of AIE underwent valvular surgery. The duration between the beginning of AIE and surgery was 23 +/- 16 (mean +/- standard deviation) days. Only 45 patients had a previous history of valvular disease. Seventy-two patients presented with aortic and 41 with mitral valve AIE. Fifty suffered from embolic events. Streptococcus species were responsible in 64 cases (23 were Streptococcus bovis) and Staphylococcus species in 24 cases. Death occurred postoperatively in 19 patients. The factors associated with fatal outcome were preoperative hemodynamic instability, age, Parsonnet and Simplified Acute Physiology Score II scores, diabetes mellitus, preexisting valvulopathy, antiarrhythmic treatment, hypoalbuminemia, renal dysfunction, duration of extracorporeal circulation, and red cell allogeneic transfusions. The type of bacteria did not influence mortality. The mean intensive care unit and hospital stays were 10 and 39 days, respectively. Eleven patients suffered from neurologic sequelae; 2 years later, 2 of them presented with severe deficit and 1 had died.

CONCLUSIONS

AIE necessitating cardiac surgery should be considered as a severe and resource-consuming disease.

Nosocomial infective endocarditis in critically ill patients: a report of three cases and review of the literature

Nosocomial infective endocarditis (NIE) is a relatively uncommon but nevertheless a serious complication affecting critically ill hospitalized patients who are frequently exposed to life-saving invasive procedures. We report three cases of NIE in a tertiary-care hospital encountered during a period of two years. The first case developed in a 50% burn-injured patient; the second in a liver transplant recipient; and the third in a renal transplant recipient. All patients met indications for cardiac surgical intervention, however, the patient who had received a liver transplant (case 2) was considered a poor candidate and unfit for surgery; she subsequently died. The other two patients underwent open-heart surgery. The burns patient (case 1) survived; conversely, the renal transplant recipient (case 3) died postoperatively. We have reviewed the literature concerning NIE in critically ill patients and describe the epidemiology, microbiology and clinical features of this uncommon infection and comment on its diagnosis and management.

A prospective multicenter study of Staphylococcus aureus bacteremia: incidence of endocarditis, risk factors for mortality, and clinical impact of methicillin resistance

Our objectives were to determine the incidence of endocarditis in patients whose Staphylococcus aureus bacteremia was community-acquired, related to hemodialysis, or hospital-acquired; to assess clinical factors that would reliably distinguished between S. aureus bacteremia and S. aureus endocarditis; to assess the emergence of methicillin-resistant S. aureus (MRSA) as a cause of endocarditis; and to examine risk factors for mortality in patients with S. aureus endocarditis. We conducted a prospective observational study in 6 university teaching hospitals; we evaluated 505 consecutive patients with Staphylococcus aureus bacteremia. Thirteen percent of patients with S. aureus bacteremia were found to have endocarditis, including 21% with community-acquired S. aureus bacteremia, 5% with hospital-acquired bacteremia, and 12% on hemodialysis. Infection was due to MRSA in 31%. Factors predictive of endocarditis included underlying valvular heart disease, history of prior endocarditis, intravenous drug use, community acquisition of bacteremia, and an unrecognized source. Twelve patients with bacteremia had a prosthetic valve; 17% developed endocarditis. Unexpectedly, nonwhite race proved to be an independent risk factor for endocarditis by both univariate and multivariate analyses. Persistent bacteremia (positive blood cultures at day 3 of appropriate therapy) was identified as an independent risk factor for both endocarditis and mortality, a unique observation not reported in other prospective studies of S. aureus bacteremia. Patients with endocarditis due to MRSA were significantly more likely to have complicating renal insufficiency and to experience persistent bacteremia than those with endocarditis due to MSSA. The 30-day mortality was 31% among patients with endocarditis compared to 21% in patients who had bacteremia without endocarditis (p = 0.055). Risk factors for death due to endocarditis included severity of illness at onset of bacteremia (as measured by Apache III and Pitt bacteremia score), MRSA infection, and presence of atrioventricular block on electrocardiogram. Patients with S. aureus bacteremia who have community acquisition of infection, underlying valvular heart disease, intravenous drug use, unknown portal of entry, history of prior endocarditis, and possibly, nonwhite race should undergo echocardiography to screen for the presence of endocarditis. We recommend that blood cultures be repeated 3 days following initiation of antistaphylococcal antibiotic therapy in all patients with S. aureus bacteremia. Positive blood cultures at 3 days may prove to be a useful marker in promoting more aggressive management, including more potent antibiotic therapy and surgical resection of the valve in endocarditis cases. MRSA as the infecting organism should be added to the list of risk factors for consideration of valvular resection in cases of endocarditis.

Infective Endocarditis in Intravenous Drug Abusers

Infective endocarditis (IE) is one of the most severe complications in intravenous drug abusers (IVDA). IE usually involves the tricuspid valve, Staphylococcus aureus is the most common etiologic agent, and it has a relatively good prognosis. Currently, between 40% and 90% of IVDA with IE are HIV infected, and the HIV epidemic has caused a decrease in the incidence of this disease, probably due to changes in drug administration habits undertaken by addicts in order to avoid HIV transmission. This review focuses on progress made over the past few years in some aspects of IE in IVDA. The pathogenesis of tricuspid endocarditis is still unknown more than 60 years after the first series. The most important advance in antibiotic therapy is that noncomplicated S. aureus right-sided endocarditis can be successfully treated with an intravenous 2-week course of nafcillin or cloxacillin plus an aminoglycoside, although probably the aminoglycoside administration could be stopped after the first 3 to 5 days. Surgery in HIV-infected IVDA with IE does not worsen the prognosis. Considering the possibility of reinfection in IVDA, prosthetic material is usually avoided. Tricuspid valvulectomy or valve repair should be considered the technique of choice in IVDA with right-sided IE. Replacement of the tricuspid valve by a cryopreserved mitral homograft is the latest introduction into clinical practice. It provides atrioventricular competence, thereby avoiding late right heart failure. Reinfections can be treated medically with a negligible reoperation rate. Overall mortality for HIV-infected or non-HIV-infected IVDA with IE is similar. However, among HIV-infected IVDA, mortality is significantly higher in those who are most severely immunosuppressed, with CD4(+) cell counts below 200/L or with AIDS criteria.

Duration of symptoms in patients with infective endocarditis

Despite progress in the management of infective endocarditis, delays in diagnosis or prior antimicrobial treatment may adversely influence the symptom duration and outcome. The duration of symptoms in patients with infective endocarditis was studied in 683 cases among 653 patients with 703 episodes of the disease; patients were hospitalized within 10 days of symptom onset in 169 (24.7%) cases. Antimicrobial therapy before hospital admission was administered to 257 (36.5%) patients. Overall mortality was 25.6%. Symptom duration was longer when antimicrobials were administered before diagnosis (58.8+/-78.1 vs. 44.8+/-54.9 days), when vegetations were detected on echocardiogram (53.5+/-68.2 vs. 38.8+/-47.3) and among patients admitted before 1990 (42.3+/-67.1 vs. 54.2+/-62.4 days). Symptom duration was shorter in patients with prosthetic valve endocarditis (26.8+/-34.2 vs. 59.3+/-71.6 days). In 54 (26.5%) episodes of prosthetic valve endocarditis, patients had symptoms for more than 30 days. Staphylococcus aureus was the most frequent agent among patients with symptoms up to 10 days (41.2%) and Streptococcus among those with symptoms over 20 days (53.9%). Symptom duration did not significantly differ in regard to medical (51.3+/-69.2 days) or surgical (46.7+/-55.7 days) treatment. Mortality increased as symptom duration decreased and was highest for patients who experienced symptoms for less than 10 days (36.1%). In some patients medical care may be delivered relatively late in the course of infective endocarditis. Administration of antibiotics previous to hospital admission increased duration of symptoms, and cardiac valve prosthesis, staphylococcal infection and death were associated with more acute disease.

Infective endocarditis and cardiac surgery in intravenous drug abusers and HIV-1 infected patients

Infective endocarditis (IE) is one of the most severe complications of parenteral drug abuse. The incidence of IE in intravenous drug abusers (IVDAs) is 2% to 5% per year, being responsible for 5% to 10% of the overall death rate. The prevalence of HIV infection among IVDAs with IE ranges between 30% and 70% in developed countries and HIV-infection by itself increases the risk of IE in IVDAs. The incidence of IE in IVDAs is currently decreasing in some areas, probably due to changes in drug administration habits by addicts to avoid HIV transmission. Overall, Staphylococcus aureus is the most common etiological agent, being usually sensitive to methicillin (MSSA). The tricuspid valve is the most frequently affected (60% to 70%), followed by the mitral and aortic valves (20% to 30%). HIV-positive IVDAs have a higher ratio of right-sided IE and S aureus IE than HIV-negative IVDAs. Response to antibiotic therapy is similar. Drug addicts with non-complicated MSSA right-sided IE can be treated with an i.v. short-course regimen of nafcillin or cloxacillin for 2 weeks, with or without addition of an aminoglycoside during the first 3 to 7 days. The prognosis of right-sided endocarditis is generally good; overall mortality is less than 5%, and with surgery is less than 2%. In contrast, the prognosis of left-sided IE is less favorable; mortality is 20% to 30%, and even with surgery is 15% to 25%. IE caused by GNB or fungi has the worst prognosis. Mortality between HIV-infected or non-HIV-infected IVDAs with IE is similar. However, among HIV-infected IVDAs, mortality is significantly higher in those who are most severely immunosuppressed, with CD4+ cell count < 200/microL or with AIDS criteria. Conversely, IE in HIV-infected patients who are not drug abusers is rare. The epidemiology of cardiac surgery in IVDAs and/or HIV-infected patients has changed in recent years. There is a decrease in IE and an increase of patients undergoing surgery (CABS) for coronary artery disease secondary to the hyperlipidemia and lipodystrophy induced by highly active antiretroviral therapy (HAART). Cardiac surgery in HIV-infected patients with or without IE does not worsen the prognosis because extracorporeal circulation did not affect the immune status after surgery. Morbidity and mortality seems to stay within the same range as the non-infected patients. In our experience, in the IE in HIV-infected IVDA group, the 1-year survival is 65% and the 5 and 10-year actuarial survival is 35%. For patients operated on for coronary artery disease, the 5-year survival is 100%.

Infective endocarditis in intravenous drug abusers and HIV-1 infected patients

Infective endocarditis (IE) is one of the most severe complications of parenteral drug abuse. The incidence of IE in intravenous drug abusers (IVDAs) is 2% to 5% per year, being responsible for 5% to 20% of hospital admissions and 5% to 10% of the overall death rate. IVDAs often develop recurrent IE. The prevalence of HIV infection among IVDAs with IE ranges between 30% and 70% in urban areas in developed countries. The incidence of IE in IVDAs is currently decreasing in some geographical areas, probably due to changes in drug administration habits undertaken by addicts in order to avoid HIV transmission. Overall, Staphylococcus aureus is the most common etiological agent, being in most geographical areas sensitive to methicillin (MSSA). The remainder of cases is caused by streptocococci, enterococci, GNR, Candida spp, and other less common organisms. Polymicrobial infection occurs in 2% to 5% of cases. The tricuspid valve is the most frequently affected (60% to 70%), followed by the mitral and aortic valves (20% to 30%); pulmonic valve infection is rare (< 1%). More than one valve is infected in 5% to 10% of cases. HIV-positive IVDAs have a higher ratio of right-sided IE and S. aureus IE than HIV-negative IVDAs. Response to antibiotic therapy is similar among HIV-infected or non-HIV-infected IVDAs. Drug addicts with non-complicated MSSA right-sided IE can be treated successfully with an i.v. short-course regimen of nafcillin or cloxacillin for 2 weeks, with or without addition of an aminoglycoside during the first 3 to 7 days. Surgery in HIV-infected IVDAs with IE does not worsen the prognosis. The prognosis of right-sided endocarditis is generally good; overall mortality is less than 5%, and with surgery less than 2%. In contrast, the prognosis of left-sided IE is less favorable; mortality is 20% to 30%, and even with surgery is 15% to 25%. IE caused by GNB or fungi has the worst prognosis. Mortality between HIV-infected or non-HIV-infected IVDAs with IE is similar. However, among HIV-infected IVDAs, mortality is significantly higher in those who are most severely immunosuppressed, with CD4+ cell count < 200/microL or with AIDS criteria. Finally, IE in HIV-infected patients who are not drug abusers is rare.

Double valve endocarditis

BACKGROUND

There are little data concerning surgical outcomes in patients with native valve endocarditis affecting both the aortic and mitral valves.

METHODS

From 1977 to 1998, 54 patients had simultaneous aortic and mitral valve grafting for native valve endocarditis. In 78%, mitral valve involvement was limited to the anterior leaflet, suggesting a jet lesion from the aortic valve. Surgical strategies included 31 valve repairs and valve replacement with mechanical (34), bioprosthetic (34), or allograft (9) prostheses. Three hundred twenty-five patient-years of follow-up were available for analysis (mean 6.0 +/- 4.8 years).

RESULTS

There were no hospital deaths. Ten-year survival was 73%. Ten-year freedom from recurrent endocarditis was 84%, with risk peaking at 3 months, followed by a constant risk of 1.3%/yr. Choice of valvar procedure did not influence mortality or reinfection risk.

CONCLUSIONS

The most common pattern of double valve infection was a jet lesion on the anterior mitral leaflet. Surgical treatment has late survival and freedom from reinfection similar to those of patients with single heart valve infection.

Infective endocarditis in children--incidence, pattern, diagnosis and management in a developing country

BACKGROUND

In developing countries, patients with infective endocarditis are referred late, there is low yield of blood cultures and incidence of rheumatic heart disease is still high.

OBJECTIVE

Evaluate clinical pattern, assess diagnostic criteria in our settings and determine outcome.

SETTING

A tertiary referral center for paediatric and adult cardiology.

PATIENTS AND METHODS

All children with infective endocarditis admitted to a single center from April 1997 to March 2000 were analysed. The diagnosis was based on Duke's criteria, which proposed two major and six minor criteria. Minor criteria were expanded to include raised acute phase reactants and presence of newly diagnosed or increasing splenomegally. The patients were stratified as definite, possible and rejected cases.

RESULTS

Of 1402 hospital admissions, 45 patients fulfilled the diagnostic criteria for infective endocarditis giving an incidence of 32 per 1000 hospital admissions. The mean age was 7.9 +/- 4 years (4 months to 16 years) with only two patients under 1 year of age. Rheumatic heart disease was the underlying lesion in 24 patients (53%) while congenital heart lesions occurred in 20 patients (45%). Previous antibiotic treatment was given in 26 patients (58%) definitely. Blood cultures were positive in 21 patients (47%); Streptococcus Viridans being the most common organism, while vegetations on echocardiography were present in 32 patients (71%). Surgery was undertaken in four patients and five patients left against medical advise. Of 10 patients with aortic valve involvement, there were three deaths (30%) and overall mortality was 13% (six patients).

CONCLUSIONS

The incidence of infective endocarditis is 32 per 1000 (3.2%) hospital admissions in a tertiary paediatric cardiology referral center. Rheumatic heart disease is still the most common underlying heart lesion. Blood cultures are positive in less than 50% of cases and echocardiography in expert hands is a more sensitive tool in our set up. Mortality is still high and aortic valve involvement in particular, carried poor prognosis.

Relapses, recurrences, valve replacements, and mortality during the long-term follow-up after infective endocarditis

BACKGROUND

Late prognosis after infective endocarditis has not been systematically studied in large series of patients with different underlying heart conditions in recent years.

METHODS

We studied an inception cohort study of 420 patients discharged after treatment of endocarditis from a university tertiary care hospital. The patients were aged 34.2+/-17.2 years (mean +/- SD), ranging from 2 months to 83 years; 270 (64.3%) were men and 150 (35.7%) were women. Mean follow-up was 6.1+/-4.3 years for survivors and 3.7+/-3.7 years for the patients who died during the follow-up. We studied the frequency and risk factors for relapses and recurrences of endocarditis, cardiac valve replacements, and deaths during the follow-up. Statistical analysis was performed through comparison of groups, of event-free survival, and risk ratios.

RESULTS

Relapses were observed in 14 (3.3%) patients. There was one recurrence of endocarditis in 48 (11.4%) patients, two (0.5%) in 2 patients, three in 1 patient (0.2%), and five (0.2%) in 1 patient. Valve replacement was performed in 83 (19.7%) patients. Ninety-eight (12.3%) patients died. Risk factors for recurrent endocarditis were increasing age (risk ratio 1.02) and male sex (risk ratio 1.61). Risk factors for valve replacement were recurrent endocarditis (risk ratio 1.62) and prosthetic valve endocarditis (risk ratio 1.61). Risk factors for death were increasing age (risk ratio 1.03) and recurrent endocarditis (risk ratio 2.06).

CONCLUSIONS

The long-term event-free survival for patients who survived their first episode of endocarditis was low. Recurrent endocarditis, prosthetic valve endocarditis, and increasing age contributed to the high rate of events during the follow-up.

Infective Endocarditis

Infective endocarditis remains a serious and potentially fatal disease. Even with appropriate therapy, mortality rates remain at about 10% to 20%. Common errors in treatment include starting antibiotics before obtaining at least three blood cultures, failing to use bactericidal drugs, stopping therapy too early, and delaying heart surgery when it is indicated. The epidemiology of endocarditis will continue to evolve, and we will see more cases that are hospital acquired, more cases associated with the presence of cardiac support devices, and cases associated with line-related bacteremia. Therefore, organisms associated with endocarditis will also likely evolve. We will see more cases due to multiresistant organisms (eg, vancomycin-resistant enterococci, glycopeptide-resistant staphylococci, and multidrug-resistant gram-negative rods) as well as yeast and fungi.

Splenic infarction in pregnancy

We present a case of splenic infarction in pregnancy, secondary to acute bacterial endocarditis. Left upper quadrant pain in pregnancy can be due to a variety of causes and in the septic or unwell patient, splenic infarct should be considered in the differential diagnosis. The diagnosis of splenic infarct should be considered especially in those at increased risk of bacterial endocarditis. Acute bacterial endocarditis can occur even in patients without any risk factors. Bacterial endocarditis is rare in pregnancy and splenic infarction is even rarer. However when it occurs, rapid diagnosis and management are necessary to minimize embolic phenomena. With the increasing use of intravenous drugs and with increasing numbers of Pacific Islanders in our pregnant population, it is important to be alert to the risk of bacterial endocarditis and to avoid serious sequelae. Patient education to the importance of medical follow-up in order to prevent such a life-threatening condition, and to avoid more complicated acute treatment, is imperative.

Infective endocarditis: an epidemiological review of 128 episodes

OBJECTIVES

The objective was to determine the current epidemiology of infective endocarditis.

PATIENTS AND METHODS

All microbiologically positive episodes of infective endocarditis treated at The University Hospital of Wales over a 9-year period from March 1987 to March 1996 was reviewed. Patients originated from the catchment area of The University Hospital of Wales or were referred from other hospitals in Wales. Data extraction was from records held in the Microbiology Department and, whenever possible, from patients' casenotes. The epidemiological parameters were: (1) age and sex of patients; (2) distribution of affected sites; (3) frequency of predisposing risk factors (cardiac and extracardiac); (4) incidence of early prosthetic valve endocarditis; and (5) mortality rates.

RESULTS

There were 128 microbiologically positive episodes of endocarditis in 125 patients. The mean age of the population was 53.1 years and the aortic valve was the most frequently involved site of infection (51.6%). A presumed source of infection was identified in 20% if episodes. The commonest predisposing cardiac risk factor in native valve episodes was bicuspid aortic valve (16.7%) but there was no identifiable cardiac risk factor in a much larger proportion (37.7%) of native valve episodes. There was a low incidence (0.6%) of culture positive early prosthetic valve episodes and low mortality rates for both native and prosthetic valve endocarditis (12.3% and 24.5%) in this study. Viridans streptococci were the predominant organisms. In prosthetic valve episodes with onset after the 60th postoperative day but within one postoperative year the identity of the isolate suggested, in most cases, perioperative valve contamination.

CONCLUSIONS

The epidemiology of infective endocarditis has undergone significant change. Inability to detect clinically common predisposing lesions, and the frequent absence of any identifiable predisposing cardiac risk factor mean that initial diagnosis is often difficult and demands a high index of suspicion. There was a low incidence of culture positive early prosthetic valve episodes and there were low mortality rates for both native and prosthetic valve endocarditis; these figures suggest improvements in cardiac care. The microbiological evidence indicates that the duration of the postoperative time period used for classifying prosthetic valve endocarditis into 'early' and 'late' episodes should be extended from 60 days to 1 year.

Outpatient intravenous antibiotic therapy for endocarditis

The clinical spectrum of endocarditis continues to evolve, as does its diagnosis and management. Outpatient parenteral antimicrobial therapy has been demonstrated to be safe and effective for medically stable patients with viridans streptococcal endocarditis. Other carefully selected and monitored patients with infective endocarditis may also be considered for completion of therapy outside the hospital setting.

-Curative and preventive antibiotic therapy in infective endocarditis-

Durack's criteria, including echocardiographic manifestations, are the current standard for the diagnosis of infective endocarditis (IE). The most common microorganisms known to cause IE are streptococci and staphylococci, and therapeutic principles are based on an association of parenteral antibiotics, as far as possible bactericidal and prolonged. Treatment also includes the search for the source of infection and its eradication. IE with negative blood cultures requires special techniques to obtain the causal microorganisms. In about half of the cases, a nosocomial bacteriaemia results in IE in patients with a prosthetic valve. Surgery is mandatory in IE with complications and/or caused by particular microorganisms; surgery is essential in most patients with a prosthetic valve. Although the presence of specific links between some procedures and the occurrence of IE has not been clearly proven, a prevention policy is nevertheless justified, considering the morbidity and mortality. Prophylaxis is indicated in patients with the cardiac conditions at risk for IE. IE prophylaxis prevails over prophylactic antibiotics usually administered for surgery.

[A case report of infective endocarditis caused by MRSA and characterized by pedicled vegetation on the posterior wall of left atrium]

We report here a case of active infective endocarditis caused by Methicilin-Resistant Staphylococcus aureus (MRSA). A 24-year-old woman was admitted to the Osaka Medical Collage Hospital with continuous fever. After admission, MRSA was detected by blood culture and chemotherapy with Vancomycin was started. However, after 1 week, her condition had not improved. Moreover, a pedicled vegetation on the posterior wall of the left atrium and mitral regurgitation due to prolapse of the anterior leaflet were revealed by transesophageal echocardiography. The vegetation grew to about 2 cm in diameter and prolapsed into the left ventricle during diastole. We performed an early operation although the infection was still active due to its rapid growth and the risk of embolism. There was a large pedicled vegetation on the posterior wall of the left atrium as shown by preoperative echocardiography, but the mitral valve appeared to be intact. Therefore, the vegetation was completely removed and the mitral annulus was plicated by Kay's method to treat the associated mitral regurgitation. Postoperatively, we administered VCM 2 g/day for 24 days. The course was uneventful. The patient was discharged from the hospital on the 31st postoperative day.

Infective endocarditis due to Stenotrophomonas (Xanthomonas) maltophilia

Stenotrophomonas maltophilia (formerly Xanthomonas maltophilia) is a gram-negative bacillus increasingly associated with serious nosocomial infections. Here, the case of a 69-year-old female patient who developed prosthetic valve endocarditis associated with this organism is described. A review of the literature revealed only 18 previous reports; eight involved native valves, the remainder prosthetic valves. Most cases were associated with risk factors, including intravenous drug abuse (6 patients), infected intravenous lines (4 patients) or a recent invasive procedure (3 patients). The course of the disease appears to be indolent, but is otherwise similar to infective endocarditis associated with other gram-negative organisms. Antimicrobial therapy is complicated by multiple drug resistance of the organism; cotrimoxazole may be beneficial, if the isolate is susceptible, in combination with another agent. Five of nine (55%) patients who underwent valve replacement survived, as compared to three of seven (43%) who received antibiotic therapy only. Hence, surgery is not essential for survival in every case and depends as much on the individual patient's course as on established criteria for valve replacement in prosthetic valve endocarditis.

Surgical treatment of endocarditis

Since early investigators first suggested that the treatment of endocarditis should include valve replacement for infections not readily controlled with medical therapy alone, the role of surgery has become expanded, yet refined, to improve the outcome of patients with this potentially fatal disease. Innovative surgical techniques have also been developed in an effort to improve the results of surgical treatment for complex sequelae of invasive infections. This article examines the current indications for surgical intervention, compares the various surgical options, and assesses the expected short-and long-term outcome after valve replacement for patients with native valve or prosthetic valve endocarditis.

A case of recurrent Candida parapsilosis prosthetic valve endocarditis: cure by medical treatment alone

A patient with recurrent fungal endocarditis on prosthetic mitral valve is presented. Candida parapsilosis was the causative agent. The patient was treated medically with conventional amphotericin during the first episode. When the disease recurred conventional amphotericin B was used again, but had to be stopped because of severe side effects. Treatment was continued with amphotericin B colloidal dispersion, followed by fluconazole for 8 months. The patient is healthy 16 months after discontinuation of fluconazole. Medical treatment of fungal endocarditis on prosthetic valves can be successful in selected cases.

Surgical treatment of infective endocarditis complicated by annular infection and cerebral infarction

The surgical treatment of nine patients with infective endocarditis (IE) complicated by annular infection and five with IE complicated by cerebral infarction is described herein. In those with annular infection, after thorough débridement of the infected tissues, valve replacement was performed at the original position in five, at the supraannular position in three, and one underwent a translocation procedure. Aortic valve replacement was able to be performed at the original position in two patients by closing the defect at the aortic annulus with a patch after through débridement. The five patients who underwent original valve position replacement recovered well. Of the three who underwent supraannular position replacement, two died of septicemia after a redo operation, and one received pacemaker implantation. The patient undergoing the translocation procedure died of intestinal infarction. In the five patients who suffered cerebral infarction due to embolus of the vegetation, valve replacement was performed between 40 h and 5 months after its onset. Although one patient died of the rapid progression of brain damage, the other four are alive and well, including two who developed mycotic cerebral aneurysm in the infarcted areas. In conclusion, early surgery for IE is mandatory irrespective of active infection, due to the high mortality and morbidity associated with serious sequelae such as annular abscess or cerebral infarction.

Fungal endocarditis--a report on seven cases and a brief review

Candida endocarditis is an unusual but severe complication of systemic infection caused by Candida albicans and occasionally by other fungal species. We describe seven cases that occurred during a period of 20 years in western Sweden. In four cases infections were located on prosthetic valves and in three cases native valves were involved. Three patients died of the disease in the acute phase. A definite diagnosis was established in one of four survivors. This patient had an aortic valve endocarditis and a saddle embolisation and was treated with immediate surgery, followed by intensive treatment with liposomal amphotericin B+ flucytosine. Fungal endocarditis is still a serious disease with a high mortality and whenever the diagnosis is suspected, antifungal therapy must be started and transesophageal sonography should be performed to visualize vegetations. Immediate surgery should be considered.

Early identification of patients with native valve infectious endocarditis at risk for major complications by initial clinical presentation and baseline echocardiography

Early identification of a high risk patient subgroup with infective endocarditis which develops a major complication (emboli, congestive heart failure, surgery for valve replacement, or death) during hospitalization would reduce morbidity, mortality and cost. Thus, for 74 patients with native valve infective endocarditis with documented vegetation by transthoracic two-dimensional echocardiogram, we reviewed 67 variables: history (15), physical examination (9), hematology/miscellaneous (7), chest X-ray (2), electrocardiogram (4), transthoracic two-dimensional echocardiograms (15) and hospital course (15). There were 48 men and 26 women, ages 45 +/- 19 years: 35 intravenous drug abusers and 39 non-users. There were 32 mitral, 21 tricuspid, 20 aortic, and 1 pulmonic valve vegetations; mean vegetation size was 1.4 +/- 0.9 cm2. Over the course of their hospitalization, 14 patients died (19%), 27 developed congestive heart failure (36%), 27 had systemic emboli (36%), and 22 required surgery (30%). The incidence of complications (death, heart failure or embolic events) did not differ between the drug abusers and non-users. Initial complaint of dyspnea on admission predicted the subsequent development of heart failure (P < 0.001), and a pre-admission embolus predicted a second in-hospital embolus (P < 0.001). Left atrial size, ventricular systolic or diastolic dimension did not effect prognosis. Importantly, a vegetation > 1.8 cm2 was 100% specific but only 30% sensitive for predicting the development of a complication. Vegetation mobility, shape, and number of cusps involved were not predictive. However, aortic valve vegetations had significantly more complications than those on the mitral valve (P < 0.03). By discriminant function analysis, 87% of major complications were predicted with the patient profile of having aortic valve vegetation, dyspnea on admission, prolonged preadmission fever, and no history of drug abuse; 75% of patients who developed heart failure were predicted by their having aortic valve vegetation, dyspnea, hypotension (systolic < 90 mm Hg), and no history of drug abuse; and 77% of patients requiring surgery were predicted by their having larger vegetation size, rales, and leftward shift of white blood cells. Thus, in native valve bacterial endocarditis with transthoracic echocardiographic documented vegetations, non-drug abusers with aortic vegetations, preadmission prolonged fevers, dyspnea, emboli and larger sized vegetations are at high risk for developing a major complication during their hospitalization.

Infective endocarditis

IE is a fascinating disease that continues to challenge the clinicians. Over the last several decades, there have been marked changes in its presentation. The morbidity and mortality have markedly improved by early diagnosis and prompt treatment using highly effective antibiotic regimens and early valve replacement surgery whenever necessary. Early diagnosis is possible by improvement in blood culture techniques and advances in transthoracic and transesophageal echocardiographic approaches. This article has reviewed the pathogenesis, microbiology, clinical presentation, diagnostic methodology, treatment, and prevention of IE.

Prosthetic valve endocarditis in the ICU. Prognostic factors of overall survival in a series of 122 cases and consequences for treatment decision

We carried out univariate and multivariate analysis of outcome among 122 patients with prosthetic valve endocarditis (PVE) admitted to our ICU between 1978 and 1992. The predominant pathogens were Staphylococcus aureus (33%), streptococci (20%), coagulase-negative staphylococci (12%), enterococci (10%), and Gram-negative bacilli (9%). At 4 months, overall survival was 66% (42 deaths). Staphylococcus aureus was the main predictor of death (75% vs 15% with other pathogens). In S aureus PVE, multivariate analysis identified the following predictors of death: prothrombin time < 30% (relative risk [RR]: 8.3), concomitant mediastinitis (RR: 4.9), heart failure (RR: 4.4), and septic shock (RR: 2.6). In PVE due to other pathogens, prothrombin time < 30% (RR: 32.26), renal failure (RR: 7.31), and heart failure (RR: 6.07) were associated with death. In S aureus PVE, survival was higher in patients who received medical-surgical therapy than in those who received medical therapy alone (9/20 [45%] vs 0/20) (p < 0.01). In PVE due to other pathogens, there was no difference in survival between patients who underwent prosthesis replacement (89%) and those who received only medical treatment (81%). Among the 65 patients who underwent heart surgery, the mortality rate and incidence of postoperative paravalvular leakage did not correlate with positive prosthesis cultures. We conclude that non-S aureus and uncomplicated PVE may be managed without valve replacement but that prompt surgical intervention should be required in all other situations.

Bivalvular endocarditis complicating pregnancy. A case report and literature review

A twenty-nine-year old woman with a history of rheumatic fever and both mitral and tricuspid valve prolapse (without cardiac effects on the echocardiogram) presented with Streptococcus viridans infective endocarditis of both the tricuspid and mitral valves at seventeen weeks' gestation. Twelve weeks before admission she underwent a dental curettage and received presumably adequate antibiotic prophylaxis. The present case was successfully managed by means of aggressive antibiotic therapy appropriate for endocarditis, with adequate and appropriate monitoring of minimal inhibitory concentration and peak and trough levels. This case exhibits the appropriate management in the three phases of therapy for valvular disease, ie prevention, treatment, and subsequent prevention of sequelae, prior to vaginal delivery in a patient with endocarditis. The pregnancy resulted in a term vaginal delivery, without maternal or fetal morbidity.

Usefulness of M-mode, 2-dimensional, and Doppler echocardiography in the diagnosis, prognosis, and management of valvular aortic stenosis, aortic regurgitation, and mitral annular calcium in older patients

OBJECTIVE

To review the diagnosis, prognosis, and management of valvular aortic stenosis, aortic regurgitation, and mitral annular calcium (MAC) with emphasis on older persons.

DATA SOURCES

A computer-assisted search of the English-language literature (MEDLINE database) followed by a manual search of the bibliographies of pertinent articles.

STUDY SELECTION

Studies on the diagnosis, prognosis, and management of valvular aortic stenosis, aortic regurgitation, and MAC were screened for review. Studies in older persons and recent studies were emphasized.

DATA EXTRACTION

Pertinent data were extracted from the reviewed articles. Emphasis was on studies involving older persons. Relevant articles were reviewed in depth.

DATA SYNTHESIS

Available data about the diagnosis, prognosis, and management of valvular aortic stenosis, aortic regurgitation, and MAC with emphasis on studies involving older persons were summarized.

CONCLUSIONS

Valvular aortic stenosis, aortic regurgitation, and MAC are degenerative cardiac disorders which are common in older people. The presence and severity of these cardiac disorders are diagnosed by M-mode, 2-dimensional, and Doppler echocardiography. M-mode, 2-dimensional, and Doppler echocardiographic techniques are also very useful in the prognosis and management of these cardiac disorders in older persons.

Medical treatment of recurrent candidemia in a patient with probable Candida parapsilosis prosthetic valve endocarditis

Fungal endocarditis is considered an absolute indication for valve replacement surgery. We describe the successful medical treatment of recurrent Candida parapsilosis candidemia with sequential treatment with amphotericin B and fluconazole in a patient with probable prosthetic valve endocarditis. Because of the presumed effectiveness of amphotericin B and fluconazole in the treatment of this patient, medical therapy should be considered as potentially useful in the treatment of recurrent C parapsilosis fungemia or endocarditis or both.

Prevention and Management of Infective Endocarditis

Infective endocarditis is an infection of the endocardial surface of the heart and usually involves one or more heart valves but may occur on septal defects or the heart wall. Its incidence is approximately 1 per 1,000 adults and 0.5 per 1,000 pediatric hospital admissions. Factors predisposing to infective endocarditis include degenerative heart disease, survivable congenital cardiac defects, use of invasive procedures, chronic immunosuppression, and intravenous drug abuse. This article discusses the pathophysiology, diagnosis, therapy, and prevention of infective endocarditis.