Perioperative care in infective endocarditis

Patients undergoing surgery for acute infective endocarditis are among those with the highest risk. Their preoperative condition has significant impact on outcomes. There are specific issues related with the preoperative situation, intraoperative findings, and postoperative management. In this narrative review, focus is placed on the most critical aspects in the perioperative period including the management and weaning from mechanical ventilation, the management of vasoplegia, the management of the chest open, antithrombotic therapy, transfusion, coagulopathy, management of atrial fibrillation, the duration of antibiotic therapy, and pacemaker implantation.

Risk factors for and consequences of positive valve cultures in patients who undergo cardiac surgery while receiving antimicrobial treatment for infective endocarditis

INTRODUCTION

Cardiac surgery is required in up to half of the patients with infective endocarditis (IE). Positive valve cultures have been associated with higher in-hospital mortality. The aims were to identify risk factors for positive valve cultures and its relation to outcome.

METHODS

Patients subjected to heart valve cultures due to surgery for IE in Skåne University Hospital, Lund, between 2012 and 2021 were identified through microbiology records. Risk factors for positive valve cultures and information on mortality and relapse were retrieved through medical records. Univariable and multivariable logistic regressions were performed.

RESULTS

A total of 345 episodes with IE in 337 patients subjected to cardiac surgery were included and valve cultures were positive in 78 (23%) episodes. In multivariable logistic regression, preoperative fever (adjusted odds ratio (AOR) 2.6, 95% confidence interval (CI) 1.2-5.6, p = 0.02), prosthetic heart valve (AOR 3.3, CI 1.4-7.9, p = 0.01), a single affected valve (AOR 4.8, CI 1.2-20, p = 0.03), blood culture findings of S. aureus, enterococci, or coagulase negative staphylococci compared to viridans streptococci (AOR 20-48, p < 0.001), and a shorter duration of antibiotic treatment (p < 0.001), were associated to positive valve culture. One-year mortality was 13% and a relapse was identified in 2.5% of episodes. No association between positive valve cultures and one-year mortality or relapse was identified.

CONCLUSIONS

Positive valve cultures were associated to short preoperative antibiotic treatment, IE caused by staphylococci, preoperative fever and prosthetic valve but not to relapse or mortality.

Impact of the Duration of Postoperative Antibiotics on the Prognosis of Patients with Infective Endocarditis

Appropriate postoperative antibiotic treatment in patients with infective endocarditis (IE) reduces the risks of recurrence and mortality. However, concerns about adverse drug reactions arise due to prolonged antibiotic usage. Therefore, we compared the recurrence and mortality rates according to the duration of postoperative antibiotic therapy in patients with IE. From 2005 to 2017, we retrospectively reviewed 416 patients with IE treated at a tertiary hospital in South Korea; among these, 216 patients who underwent heart valve surgery and received appropriate antibiotics were enrolled. The patients were divided into two groups based on the duration of usage of postoperative antibiotic therapy; the duration of postoperative antibiotic therapy was more than two weeks in 156 patients (72.2%) and two weeks or less in 60 patients (27.8%). The primary endpoint was IE relapse. The secondary endpoints were 1-year IE recurrence, 1-year mortality, and postoperative complication rates. The median age was 53 (interquartile range: 38-62) years. The relapse rate of IE was 0.9% (2/216). There was no statistical difference in relapse (0.0% vs. 1.3%, p = 0.379), 1-year recurrence (1.7% vs. 1.3%, p = 0.829), or 1-year mortality (10.0% vs. 5.8%, p = 0.274) between patients with postoperative antibiotic administration of two weeks or less versus more than two weeks. The duration of postoperative antibiotic therapy did not affect the 1-year mortality rate (log-rank test, p = 0.393). In conclusion, there was no statistically significant difference in recurrence, mortality, or postoperative complications according to the duration of postoperative antibiotic therapy.

Paradoxical embolisation in right-sided infective endocarditis and patent foramen ovale

Intravenous drug use (IVDU) is a growing public health crisis worldwide. A known complication of IVDU is right-sided infective endocarditis (RSIE) involving the tricuspid valve. As the tricuspid valve is burdened with infectious vegetations, it becomes a potential source of pulmonary and, very rarely, paradoxical systemic emboli. We report two patients with RSIE involving the tricuspid valve presenting with acute change in mental status. Subsequent imaging demonstrated embolisation to the brain in the setting of elevated right atrial pressures and the presence of a patent foramen ovale (PFO) with right-to-left shunting. We employed a strategy of percutaneous closure of PFO, to prevent further embolisation, as a successful bridge to definitive surgical management of RSIE. We emphasise that clinicians should evaluate for intracardiac shunting and pursue transesophageal echocardiography when encountering systemic emboli of unknown origin, particularly in patients with RSIE.

Impact of Valve Culture Positivity on Prognosis in Patients with Infective Endocarditis Who Underwent Valve Surgery

Introduction

Infective endocarditis (IE) is a severe and fatal infection with high in-hospital and overall mortality rates of approximately up to 30%. Valve culture positivity was associated with in-hospital mortality and postoperative complications; however, few studies have analyzed the relationship between valve cultures and overall mortality over a long observation period. This study aimed to compare the association of valve culture positivity with overall mortality in patients with IE who underwent valve surgery.

Methods

A total of 416 IE patients admitted to a tertiary hospital in South Korea from November 2005 to August 2017 were retrospectively reviewed. A total of 202 IE patients who underwent valve surgery and valve culture were enrolled. The primary endpoint was long-term overall mortality. Kaplan–Meier curve and Cox proportional hazards model were used for survival analysis.

Results

The median follow-up duration was 63 (interquartile range, 38–104) months. Valve cultures were positive in 22 (10.9%) patients. The overall mortality rate was 15.8% (32/202) and was significantly higher in valve culture-positive patients (36.4%, p = 0.011). Positive valve culture [hazard ratio (HR) 3.921, p = 0.002], Charlson Comorbidity Index (HR 1.181, p = 0.004), Coagulase-negative staphylococci (HR 4.233, p = 0.001), new-onset central nervous system complications (HR 3.689, p < 0.001), and new-onset heart failure (HR 4.331, p = 0.001) were significant risk factors for overall mortality.

Conclusions

Valve culture positivity is a significant risk factor for long-term overall mortality in IE patients who underwent valve surgery. The importance of valve culture positivity needs to be re-evaluated, as the valve culture positivity rate increases with increasing early surgical intervention.

OUP accepted manuscript

Background

Recent literature has demonstrated that partial oral antibiotic treatment of infectious endocarditis is non-inferior to IV therapy in select patients. Despite the rising incidence of injection drug use-related endocarditis, partial oral therapy has not been well studied in persons who inject drugs.

Objectives

To evaluate the rate of relapsed infection and 90 day mortality in patients with infectious endocarditis treated with partial oral antibiotic therapy.

Methods

Consecutive patients with infectious endocarditis treated with partial oral antibiotic therapy were identified by study investigators and reviewed by independent clinicians. The decision to use partial oral antibiotic therapy was made by the institution’s multidisciplinary endocarditis team.

Results

In 11 cases of infective endocarditis treated with partial oral antibiotic therapy, 9 of which were complicated by injection drug use, there were no relapsed infections with the primary organism. Five patients underwent surgical valve replacement, and the median duration of oral antibiotic therapy was 23 days. All patients survived to in-hospital discharge and 90 days post-discharge. Ten patients followed up with an infectious diseases provider after discharge.

Conclusions

These data add to existing literature demonstrating non-inferior outcomes with partial oral antibiotic treatment when compared with IV antibiotic treatment alone in patients with endocarditis, including persons who inject drugs.

The Clinical Impact of Implementation of a Multidisciplinary Endocarditis Team

BACKGROUND

Infectious endocarditis is associated with substantial in-hospital mortality of 15-20%. Effective management requires coordination between multiple medical and surgical subspecialties which can often lead to disjointed care. Previous European studies have identified multidisciplinary endocarditis teams as a tool for reducing endocarditis mortality.

METHODS

The multidisciplinary endocarditis Team was formed in May 2018. The group developed an evidence-based algorithm for management of endocarditis that was used to provide recommendations for hospitalized patients over a 1-year period. Mortality outcomes were then retroactively assessed and compared to a historical control utilizing propensity matching.

RESULTS

Between June 2018 and June 2019 the team provided guideline-based recommendations on 56 patients with Duke Criteria definite endocarditis and at least 1 AHA indication for surgery. The historical control included 68 patients with definite endocarditis and surgical indications admitted between July 1^st, 2014 to June 30^th, 2015. In-hospital mortality decreased significantly from 29.4% in 2014-2015 to 7.1% in 2018-2019 (p<0.0001). There was a non-significant increase in the rate of surgical intervention after implementation of the team (41.2% vs 55.4%; p=0.12). Propensity score matching demonstrated similar results.

CONCLUSIONS

Implementation of a multidisciplinary endocarditis team was associated with a significant 1-year decrease in all-cause in-hospital mortality for patients with definite endocarditis and surgical indications, in the presence of notable differences between the two studied cohorts. In conjunction with previous studies demonstrating their effectiveness, this data supports that widespread adoption of endocarditis teams in North America could improve outcomes for this patient population.

Infective Endocarditis Guidelines: The Challenges of Adherence-A Survey of Infectious Diseases Clinicians

Background

Guidelines exist to aid clinicians in managing patients with infective endocarditis (IE), but the degree of adherence with guidelines by Infectious Disease (ID) physicians is largely unknown.

Methods

An electronic survey assessing adherence with selected IE guidelines was emailed to 1409 adult ID physician members of the Infectious Diseases Society of America’s Emerging Infections Network.

Results

Five hundred fifty-seven physicians who managed IE responded. Twenty percent indicated that ID was not consulted on every case of IE at their hospitals, and 13% did not recommend transthoracic echocardiography (TTE) for all IE cases. The duration of antimicrobial therapy was timed from the first day of negative blood cultures by 91% of respondents. Thirty-four percent of clinicians did not utilize an aminoglycoside for staphylococcal prosthetic valve IE (PVE). Double β-lactam therapy was “usually” or “almost always” employed by 83% of respondents for enterococcal IE. For patients with active IE who underwent valve replacement and manifested positive surgical cultures, 6 weeks of postoperative antibiotics was recommended by 86% of clinicians.

Conclusions

The finding that adherence was <90% with core guideline recommendations that all patients with suspected IE be seen by ID and that all patients undergo TTE is noteworthy. Aminoglycoside therapy of IE appears to be declining, with double β-lactam regimens emerging as the preferred treatment for enterococcal IE. The duration of postoperative antimicrobial therapy for patients undergoing valve replacement during acute IE is poorly defined and represents an area for which additional evidence is needed.

Clinical Practice Update on Infectious Endocarditis

Infectious endocarditis is a highly morbid disease with approximately 43,000 cases per year in the United States. The modified Duke Criteria have poor sensitivity; however, advances in diagnostic imaging provide new tools for clinicians to make what can be an elusive diagnosis. There are a number of risk stratification calculators that can help guide providers in medical and surgical management. Patients who inject drugs pose unique challenges for the health care system as their addiction, which is often untreated, can lead to recurrent infections after valve replacement. There is a need to increase access to medication-assisted treatment for opioid use disorders in this population. Recent studies suggest that oral and depo antibiotics may be viable alternatives to conventional intravenous therapy. Additionally, shorter courses of antibiotic therapy are potentially equally efficacious in patients who are surgically managed. Given the complexities involved with their care, patients with endocarditis are best managed by multidisciplinary teams.

Reduced Incidence of Carbapenem-Resistant Klebsiella pneumoniae Infections in Cardiac Surgery Patients after Implementation of an Antimicrobial Stewardship Project

Infections due to carbapenem-resistant Klebsiella pneumoniae (CR-Kp) are associated with increased mortality in cardiac surgery patients. In this short communication, we report on the changes in the incidence of CR-Kp colonization and CR-Kp infection in cardiac surgery patients from 2014 to 2018 in a teaching hospital in Italy, after the implementation of an antimicrobial stewardship project in 2014. During the study period, 2261 patients underwent open-heart surgery. Of them, 130 were found to be colonized by CR-Kp (5.7%) and 52 developed a postoperative CR-Kp infection (2.3%). The crude in-hospital mortality in patients with CR-Kp infections was 48% (25/52). The incidences of both CR-Kp colonization (incidence rate ratio (IRR) 0.82, 95% confidence intervals (CI) 0.78-0.86, p < 0.001) and CR-Kp infection (IRR 0.76, 95% CI 0.69-0.83, p < 0.001) considerably decreased over the study period. This encouraging result should prompt further concerted efforts, directed towards retaining the positive impact of stewardship and infection-control interventions on CR-Kp-related morbidity in the long term.