Results of surgical treatment for infective endocarditis in intravenous drug users

A novel technique for the percutaneous removal of tricuspid valve vegetations utilizing the Inari Flowtriever System

Right-sided infective endocarditis is a common entity for which surgical intervention is frequently high-risk. Considering its invasive nature, potential complications, and challenging patient population, a less invasive endovascular option is desirable. The previous series have demonstrated the feasibility of percutaneous therapy for tricuspid valve (TV) vegetation utilizing a filter-based bypass circuit. However, the limited availability of a specialized team, resources, procedural complexity, and large bore sheath size restrict the broad adoption of this technique. The Inari FlowTriever System (Inari Medical) is an endovascular, catheter-based, aspiration, and mechanical thrombectomy system indicated for the removal of large-volume venous thrombus and pulmonary emboli. Independent of anesthesia, perfusion, or advanced imaging, this device's characteristics uniquely improve the operator's ability to safely remove unwanted debris from complex anatomy. This report describes the first, utilization of the Inari FlowTriever System for the removal of massive and inoperable TV vegetation.

Long term surgical outcomes for infective endocarditis in people who inject drugs: a systematic review and meta-analysis

Background

In recent years, the number of infective endocarditis (IE) cases associated with injection drug use has increased. Clinical guidelines suggest deferring surgery for IE in people who inject drugs (PWID) due to a concern for worse outcomes in comparison to non-injectors (non-PWID). We performed a systematic review and meta-analysis of long-term outcomes in PWID who underwent cardiac surgery and compared these outcomes to non-PWID.

Methods

We systematically searched for studies reported between 1965 and 2018. We used an algorithm to estimate individual patient data (eIPD) from Kaplan-Meier (KM) curves and combined it with published individual patient data (IPD) to analyze long-term outcomes after cardiac surgery for IE in PWID. Our primary outcome was survival. Secondary outcomes were reoperation and mortality at 30-days, one-, five-, and 10-years. Random effects Cox regression was used for estimating survival.

Results

We included 27 studies in the systematic review and 19 provided data (KM or IPD) for the meta-analysis. PWID were younger and more likely to have S. aureus than non-PWID. Survival at 30-days, one-, five-, and 10-years was 94.3, 81.0, 62.1, and 56.6% in PWID, respectively; and 96.4, 85.0, 70.3, and 63.4% in non-PWID. PWID had 47% greater hazard of death (HR 1.47, 95% CI, 1.05–2.05) and more than twice the hazard of reoperation (HR 2.37, 95% CI, 1.25–4.50) than non-PWID.

Conclusion

PWID had shorter survival that non-PWID. Implementing evidence-based interventions and testing new modalities are urgently needed to improve outcomes in PWID after cardiac surgery.

Making the Cut: Perspectives on the Surgical Management of Infective Endocarditis Among People Who Use Intravenous Drugs

In this article we review the perspectives in the literature around surgical treatment for infective endocarditis (IE) in people who use intravenous drugs (PUID). PUID are at increased risk for IE; however, controversy exists regarding how to best manage these patients. We explore the outcomes for surgical treatment in PUID with IE, contrasting these with patients with IE who do not use drugs. We describe some of the perspectives in the literature around second valve replacement for PUID with IE, arguing that moralistic arguments are not on the basis of evidence and perpetuate the stigma experienced by PUID who seek treatment for IE. Finally, we explore the role of substance use interventions in the treatment of PUID with IE, and advocate for further evidence. PUID with IE are a highly stigmatized patient subgroup for whom best practice management strategies are not always implemented, emphasizing the need for further research and advocacy.

Daptomycin compared to standard therapy for the treatment of native valve endocarditis

INTRODUCTION

In a recent randomized trial of Staphylococcus aureus bacteremia and native valve endocarditis, daptomycin was found not inferior to standard therapy. We summarized findings in the subgroup of patients with endocarditis according to the Duke criteria.

METHODS

Patients were randomly assigned to receive daptomycin 6 mg/kg/day or standard therapy (vancomycin 1g every 12h or antistaphylococcal penicillin 2g every 4h, both with gentamicin 1mg/kg every 8h for the first 4 days). The primary end point was success in the modified intent-to-treat population 6 weeks after the end of therapy.

RESULTS

Fifty-three patients were included: 35 with right-sided endocarditis (RIE) and 18 with left-sided endocarditis (LIE). The success rates in patients with RIE were similar between daptomycin and the comparator (42% vs 44%). Patients with RIE with septic pulmonary infarcts responded similarly to treatment with daptomycin and standard therapy (60% vs 67%). In the LIE population, treatment success rates were poor in both arms (11% vs 22%).

CONCLUSION

Daptomycin is an efficacious and well-tolerated alternative to standard therapy in the treatment of RIE. Patients with LIE had a poor outcome regardless of the treatment received. Daptomycin is also effective in treating endocarditis with septic pulmonary infarcts.

In-hospital and long-term mortality in infective endocarditis in injecting drug users compared to non-drug users: a retrospective study of 192 episodes

In a retrospective study, in-hospital and long-term mortality for patients with infective endocarditis (IE) was analysed. The study was conducted at a department of infectious diseases in Stockholm, Sweden. Mortality was compared between injecting drug users (IDUs) and patients without drug abuse (non-IDUs). 192 episodes of IE from 1995 to 2000 were analysed, 60 in IDUs and 135 in non-IDUs, median follow-up 4.4 y. Episodes were classified using the Duke criteria: 145 definite and 47 possible. Of 53 definite episodes in IDUs, 55% were right-sided IE and 43% left-sided IE (including combined left- and right-sided). Surgical treatment was used in 34/145 definite episodes, all being left-sided IE. The in-hospital mortality was 14/145 (9.6%). There was no difference in in-hospital mortality between patient groups with left-sided IE. The IDU patients with left-sided IE had a higher long-term mortality with the increased mortality rate explained by late deaths in the surgically treated IDUs. Treatment results for IDUs with right-sided IE were good with no in-hospital mortality, no relapses and no increase in long-term mortality. This difference in prognosis between left-sided and right-sided IE in IDUs makes high quality echocardiography important to identify patients with left-sided IE and worse prognosis.

Perioperative blood transfusion and blood conservation in cardiac surgery: the Society of Thoracic Surgeons and The Society of Cardiovascular Anesthesiologists clinical practice guideline

BACKGROUND

A minority of patients having cardiac procedures (15% to 20%) consume more than 80% of the blood products transfused at operation. Blood must be viewed as a scarce resource that carries risks and benefits. A careful review of available evidence can provide guidelines to allocate this valuable resource and improve patient outcomes.

METHODS

We reviewed all available published evidence related to blood conservation during cardiac operations, including randomized controlled trials, published observational information, and case reports. Conventional methods identified the level of evidence available for each of the blood conservation interventions. After considering the level of evidence, recommendations were made regarding each intervention using the American Heart Association/American College of Cardiology classification scheme.

RESULTS

Review of published reports identified a high-risk profile associated with increased postoperative blood transfusion. Six variables stand out as important indicators of risk: (1) advanced age, (2) low preoperative red blood cell volume (preoperative anemia or small body size), (3) preoperative antiplatelet or antithrombotic drugs, (4) reoperative or complex procedures, (5) emergency operations, and (6) noncardiac patient comorbidities. Careful review revealed preoperative and perioperative interventions that are likely to reduce bleeding and postoperative blood transfusion. Preoperative interventions that are likely to reduce blood transfusion include identification of high-risk patients who should receive all available preoperative and perioperative blood conservation interventions and limitation of antithrombotic drugs. Perioperative blood conservation interventions include use of antifibrinolytic drugs, selective use of off-pump coronary artery bypass graft surgery, routine use of a cell-saving device, and implementation of appropriate transfusion indications. An important intervention is application of a multimodality blood conservation program that is institution based, accepted by all health care providers, and that involves well thought out transfusion algorithms to guide transfusion decisions.

CONCLUSIONS

Based on available evidence, institution-specific protocols should screen for high-risk patients, as blood conservation interventions are likely to be most productive for this high-risk subset. Available evidence-based blood conservation techniques include (1) drugs that increase preoperative blood volume (eg, erythropoietin) or decrease postoperative bleeding (eg, antifibrinolytics), (2) devices that conserve blood (eg, intraoperative blood salvage and blood sparing interventions), (3) interventions that protect the patient's own blood from the stress of operation (eg, autologous predonation and normovolemic hemodilution), (4) consensus, institution-specific blood transfusion algorithms supplemented with point-of-care testing, and most importantly, (5) a multimodality approach to blood conservation combining all of the above.

Bacteriological Outcome after Valve Surgery for Active Infective Endocarditis: Implications for Duration of Treatment after Surgery

BACKGROUND

There has been no systematic evaluation of outcome after surgery for infective endocarditis with respect to duration of antibiotic treatment.

METHODS

We performed a retrospective chart review of episodes of valve surgery for active infective endocarditis at Green Lane Hospital (Auckland, New Zealand) for 1963-1999. We recorded the duration of antibiotic treatment before and after valve surgery; the extent of infection at operation; Gram stain, culture, and histopathological testing results for valve samples; and the bacteriological outcome after surgery. The primary outcome measure was relapse, defined as endocarditis due to the same species within 1 year after surgery.

RESULTS

For the 358 patients in our study, the median duration of follow-up was 4.8 years. Thirty-two patients (9%) had 36 subsequent episodes of endocarditis. Relapse occurred after 3 (0.8%) of the operations (95% CI, 0.2%-2.0%). Relapse of infection was unrelated to the duration of antibiotic treatment before or after surgery, positive valve culture results, positive Gram stain results, or perivalvular infection. Since 1994, we have reduced the duration of antibiotic treatment by approximately 7 days for those with positive valve culture results and by approximately 14 days for those with negative valve culture results, without any increase in the number of relapses.

CONCLUSIONS

Relapse is an uncommon event following surgery for endocarditis. Commonly suggested indications for prolonging postoperative treatment are not associated with higher relapse rates, and their relevance is debatable. We conclude that it is unnecessary to continue treatment for patients with negative valve culture results for an arbitrary 4-6-week period after surgery. Two weeks of treatment appears to be sufficient, and, for those operated on near the end of the standard period of treatment, simply completing the planned course should suffice.

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.

Current best practices and guidelines. Indications for surgical intervention in infective endocarditis

Optimal diagnosis and management of patients with infective endocarditis requires sound clinical judgment based on extensive experience. This is especially important in regard to the indications and timing for surgery. To achieve the best possible outcomes, surgical intervention during treatment is required in 25% to 30% of patients with infective endocarditis. Heart failure and progressive left-sided valvular dysfunction are the most common indications for operation. Valve repair should be considered as an alternative to valve replacement whenever feasible, especially in younger patients. Successful management of perivalvular abscesses and prosthetic valve infections requires radical removal of infected tissue followed by reconstructive procedures performed by experienced surgeons. Emergency or urgent surgery should seldom be delayed.

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%.

Current best practices and guidelines indications for surgical intervention in infective endocarditis

Optimal diagnosis and management of patients with infective endocarditis requires sound clinical judgment based on extensive experience. This is especially important in regard to the indications and timing for surgery. To achieve the best possible outcomes, surgical intervention during treatment is required in 25% to 30% of patients with infective endocarditis. Heart failure and progressive left-sided valvular dysfunction are the most common indications for operation. Valve repair should be considered as an alternative to valve replacement whenever feasible, especially in younger patients. Successful management of perivalvular abscesses and prosthetic valve infections requires radical removal of infected tissue followed by reconstructive procedures performed by experienced surgeons. Emergency or urgent surgery should seldom be delayed.

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.

Value of echocardiographic findings in predicting cardiovascular complications in infective endocarditis

Echocardiography allows the detection of vegetations and estimation of valvular dysfunction in patients with infective endocarditis. The value of echocardiographic findings in predicting cardiac and other vascular complications in infective endocarditis is not well understood. Identification of high-risk patients and early surgery may improve their prognosis. The authors reviewed echocardiographic findings and related them to the development of congestive heart failure, systemic embolism, and the need for surgery or the risk of death without surgery in patients with infective endocarditis. There were 125 episodes of endocarditis in 114 patients (84 episodes [67%] in men) with a mean age +/- standard deviation of 37 +/- 7 years. Vegetations were detected by echocardiography on at least 1 valve in 87 episodes (70%); on the mitral valve in 36 episodes (29%); on the aortic valve in 21 episodes (17%); and on the tricuspid valve in 45 episodes (36%). Severe aortic regurgitation was present in 9 episodes (7%) and severe mitral regurgitation in 4 instances (3%). In 12 of 21 episodes (57%) of vegetations on the aortic valve compared with 15 of 104 patients (14%) without vegetations on the aortic valve (p < 0.001), and in 8 of 9 instances (89%) of severe aortic regurgitation compared with 19 of 116 episodes (16%) without severe aortic regurgitation (p<0.00001), the patients developed congestive heart failure. In 18 of 55 episodes (33%) of vegetations on the aortic/mitral valve compared with 17 of 70 episodes (25%) without vegetations on the aortic valve/mitral valve (p = NS), the patients developed systemic embolism. In 13 of 21 episodes (62%) of vegetations on the aortic valve compared with 19 of 104 episodes (19%) without vegetations on the aortic valve (p < 0.001), and in 8 of 9 episodes (89%) of severe aortic regurgitation compared with 24 of 116 episodes (21%) without severe aortic regurgitation (p < 0.00001), the patients either had surgery or died without surgery. Echocardiographic findings do not reliably predict the risk of systemic embolism in patients with infective endocarditis. Vegetations on the aortic valve and severe aortic regurgitation detected by echocardiography predict a high risk of developing congestive heart failure, and for the combined outcome of requiring surgery, or dying without surgery in infective endocarditis. Early surgery may improve the outlook for survival of these patients.

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.

Factors Affecting the Surgical Management of Infective Endocarditis

Congestive heart failure and septic embolism complicate the clinical course of patients with infective endocarditis (IE). This study reviews the clinical records of patients with systemic disease secondary to IE and stratifies their disease severity according to individual risk factors and medical, and surgical interventions. The hospital records of all patients presenting to our institution from 1992 through 1997 with heart valve destruction secondary to IE were reviewed. Ten patients with hemodynamically significant valve lesions were included in this study: seven with aortic valve disease and two with mitral valve disease, and one with combined aortic and mitral valve lesions. All were diagnosed by echocardiogram. All ten patients experienced systemic septic arterial emboli: four intracranial lesions, four visceral lesions, and three extremity arterial occlusive events. Two patients required peripheral arterial repair. Cultures revealed infection secondary to Staphylococcus aureus in five, Streptococcus species in three, Coxiella species in one, and an unidentified organism in one patient. Seven patients underwent valve replacement. Three patients died from their disease processes. Statistical significance was established by Wilcoxon rank analysis with a two-tailed P < 0.05. Patients with IE secondary to staphylococcal infections suffered a more acute and virulent disease process (P = 0.04), with a 40 per cent mortality rate in the first 48 hours. There was no increased incidence of embolization associated with longer duration of symptoms (P = 0.32). Surgical repair conferred improved clinical outcome as compared with no surgical intervention (P = 0.03). Improved patient outcome was associated with nonstaphylococcal infection (P = 0.02), and a successful initial antibiotic regimen (P = 0.03). Peripheral arterial repair was successful in both cases.

Cardiac infections: medical and surgical therapies

Infections of the heart can be acute or subacute, depending on host susceptibility, the cause and associated virulence, early diagnosis, and effective therapy. The following review will discuss the causes, clinical manifestations, diagnosis, and medical or surgical management of infective endocarditis, prosthetic valve endocarditis, myocarditis, and pericarditis. Nursing considerations emphasize understanding the pathogenesis, early recognition of signs and symptoms, and appropriate prevention and intervention.