2023 ESC Guidelines - Infective Endocarditis. What's new?

The farewell of 2023 to us is some important updates involving Cardiology and Cardiac Surgery. Among all the updates there is one such useful like a surgical tool for a valve surgeon; a tool as effective as a scissor or a pickup. I am talking about guidelines. A tool that helps all of us in the decision making process in the hope of offering our patients all the best.

Last in August 2023 and then in December 2023 the ESC (European Society of Cardiology) came out with new guidelines for the management of infective endocarditis (IE) and its corrections endorsed by the EACTS (European Society of Thoracic Surgery) and the EANM (European Associacion of Nuclear Medicine); these guidelines will replace the 2015 edition.

IE is a serious and potentially life-threatening medical condition characterized by the inflammation of the endocardium, which is the inner lining of the heart chambers and heart valves. This inflammation is typically caused by the presence of infectious agents, such as bacteria or fungi, in the bloodstream. These microorganisms can adhere to damaged areas of the heart valves or other cardiac structures, forming vegetations that may lead to the destruction of heart tissue and the development of complications. IE often presents with symptoms like fever, fatigue, and cardiac-related issues. Prompt diagnosis and appropriate treatment, often involving antibiotics and sometimes surgical intervention, are crucial in managing this condition.

IE is a major public health challenge with an estimated incidence of 13.8 cases per 100 000 individuals per year.

Medical management and surgical indication in IE are challenge and the decision-making process is not easy.

Let's see what's new with the 2023 ECS Guidelines?

PREVENTION:

When the Antibiotic Prophylaxis is recommended ?

• Patients with previous IE undergoing oro-dental procedures at high risk for infective endocarditis [I B]*
• Patients with surgically implanted prosthetic valves and with any material used for surgical cardiac valve repair undergoing oro-dental procedures at high risk for infective endocarditis [I C]*
• Patients with transcatheter implanted aortic and pulmonic valves undergoing oro-dental procedures at high risk for infective endocarditis [I C]*
• Patients with untreated cyanotic congenital heart disease and patients treated with transcatheter or surgical procedures with postoperative palliative shunts, conduits or other prostheses. After surgical repair, in the absence of residual defects or prostheses, antibiotic prophylaxis is recommended only for the first 6 months after the procedure [I C]*
• Antibiotic prophylaxis covering S. Aureus is recommended in patients undergoing implantation of any intracardiac electronic device like pacemakers and automatic intracavitary defibrillators [I A]*

• Antibiotic prophylaxis should be considered in patients with transcatheter mitral and tricuspid valve repair undergoing oro-dental procedures at high risk for infective endocarditis [IIa B]*

ENDOCARDITIS TEAM

• Diagnosis and management of patients with complicated IE are recommended to be performed at an early stage in a Heart Valve Center, with immediate surgical facilities and an Endocarditis Team [I B]*

• Uncomplicated IE managed in a Referring Center, early and regular communication between the local and the Heart Valve Center Endocarditis Team is recommended [I B]*

ECHOCARDIOGRAPHY in IE

• Transesophageal Echocardiogram (TOE) is recommended in patients with suspected IE, even in cases with positive transthoracic echocardiogram (TTE), except for isolated right-sided native valve IE with good quality TTE examination and unequivocal echocardiographic findings [I C]*
• TTE and TOE are recommended in case of suspected intracardiac elctronic devices IE to identify vegetations [I B]*

MAIN INDICATION FOR SURGERY

• Urgent surgery is indicated in IE with vegetations >10 mm and other indication for surgery (i.e. severe valve regurgitation/stenosis/abscess) [I C]*
• Urgent surgery may be considered in aortic and mitral IE with vegetations >10 mm without severe valve dysfuntion or without clinical evidence of embolism and low surgical risk [IIb B]*

SURGICAL INDICATION FOR RIGHT-SIDED IE

Surgery is indicated for patient presenting right-sided IE who are receiving appropriate antibiotic therapy when:

• Severe right ventricle (RV) dysfunction secondary to severe tricuspid regurgitation (TR) not responsive to diuretic therapy is present [I B]*
• Are present persisting vegetations with respiratory insufficiency requiring ventilatory support after recurrent pulmonary emboli [I B]*
• Large tricuspid vegetations >20mm are present after recurrent septic pulmonary emboli [I C]*
• There is a simultaneous involvement of left-heart structures [I C]*

NEUROLOGICAL COMPLICATIONS of IE

Head imaging might be very helpful in detecting potential life-threatening complication of septic emboli like intracranial hemorrhage/ischemia and mycotic aneurysm.

• Brain CT (computed tomography) or MRA (Magnetic Resonance Angiography) is recommended in patients with IE and suspected infective cerebral aneurysms [I B]*
• If non-invasive imaging techniques are negative and the suspicion of infective cerebral aneurysm remains, invasive angiography should be considered [IIa B]*

SURGICAL INDICATION AFTER A NEUROLOGICAL EVENT

This is definitively the most difficult scenario in the decision making process. Let's see which are the recommendation for cardiac surgery after neurological complication in active IE.

• After a (TIA) transient ischemic attack, cardiac surgery, if indicated, is recommended without delay [I B]*
• After a stroke, surgery is recommended without any delay in presence of heart failure, uncontrolled infection, persistent high risk of embolism as long as coma is absent and intracranial hemorrhage has been excluded by CT or MRI [I B]*
• Following intracranial hemorrhage, delaying cardiac surgery, if possible, > 1 month. Frequent clinical re-assessment and imaging should be considered [IIa C]*
• Following intracranial hemorrhage, in presence of heart failure, uncontrolled infection, persistent high risk of embolism urgent/emergent surgery should be considered weighing the likelihood of a meaningful neurological outcome [IIa C]*

ANTI-THROMBOTIC THERAPY

Management of antiplatlets and anticoagulants agents during IE includes:

• Interruption of antiplatlets or anticoagulants agents is recommended in the presence of major bleeding (including intracranial hemorrhage) [I C]*

INTRACARDIAC ELECTRONIC DEVICES RELATED (pacemakers/AICD) IE

• Complete device extraction should be considered in case of valvular IE, even without definite lead involvement, taking into account the identified pathogen and requirement for valve surgery [IIa C]*
• In cases of possible device-related IE or occult Gram-postive bacteremia or fungaemnia, complete system devcie removal should be considered in case bacteremia/fungaemia persists after a course of antimicrobial therapy [IIa C]*
• In cases of possible device-related IE or occult Gram-negative bacteremia or fungaemnia, complete system device removal should be considered in case bacteremia/fungaemia persists after a course of antimicrobial therapy [IIb C]
• If the electronic device reimplantation is indicated after extraction for devices-related IE it is recommended to be performed: - at a distant site from the previous generator - as late as possible from the extraction - once signs/symptoms of the infection have abated - until blood coltures are negative for at least 72 hours in the absence of vegetations - or blood coltures are negative for at least 2 weeks if vegetations were visualized

*[I/II/IIIa-b ; A/B/C] = Class and Level of evidence

These were the revised recommendations from the previous 2015 edition. A deeper knowledge of the IE and its outcomes pushed the action towards an indication of class I and II for prevention, imaging, multidisciplnary approach and surgery.

SURGEON'S STANDPOINT

In this Multidsciplinary Team the Surgeon is the one is taking into account a huge responsibility offering or not surgery to these unfortunate patients.

The decision making algorithm for surgery takes into account basically three elements:

• Heart Failure
• Uncontrolled Infection
• Emboli

It's important the urgent and emergent surgery meaning. The ECS Task Force has defined urgent surgery as that requiring intervention within 3-5 days without any further delay. Emergency surgery means within 24 hours irrespectively the pre-op duration of the antibiotic therapy. There is third group of patients requiring non-urgent surgery; it means within the same admission.

The worst scenario for a cardiac surgeon is where the indication for surgery is following a neurological event. The fear of having a massive intracranial hemorrhage after systemic heparinization required for CPB is always present and unpredictable. Unfortunately a clear pathway for patients suffering a neurological event is lacking because randomized studies are impractical and cohort studies are suffering of bias that can be partially compensated by statistical analysis.

The majority of publications demonstrate lower risk of secondary hemorrhagic conversion of uncomplicated ischemic lesions than the risk of recurrent embolism under antibiotic treatment. There is a general trend to offer early surgery in light of improved operative outcomes and survival benefits observed with the operative management instead of an observational or delayed strategy. Embracing a patient-based strategy the risk of neurological exacerbation during surgery needs to be balanced against that of delaying a cardiac operation in terms of hemodynamic deterioration/performance, progression of the infection, embolic risk. Always take into account a 2-7% of post-operative hemorrhagic conversion after pre-operative stroke. The suggested algorithm for patient presenting neurological complication from IE is the following:

Emphasis on inclusion/exclusiopn criteria for surgery has been placed on the residual quality of life after the neurological event, presence/absence of cardiogenic shock and the type of stroke.

SPECIFIC SITUATIONS

Prosthetic valve IE (PVE). This is a very unfortunate situation with the highest reported in-hospital mortality ranging between 20 and 40%. The best therapeutic option for PVE is still debated and despite more than 80% of patient presenting PVE have clear indication for surgery is performed in 50 to 70% of them because the high surgical risk profile.

Surgery for PVE follows the general indication for IE on native valves, but in this setting meticulous and radical debridement of then infected material should be carried out. Early PVE following prosthetic valve replacement is a separate entity deserving a Specific recommendation [I C] stating that surgery is indicated for early PVE (within 6 months of valve implantation) with new valve placement and complete debridement.

If a transcatheter valve is involved in PVE the decision to proceed with surgery should be individualized balancing the surgical risk and the prognosis of the medical treatment alone. In the absence of prohibitive surgical risk surgery may be considered for patient presenting local extension of the infection. In selected patients with healed infection a transcatheter valve-in-valve, if prosthetic dysfunction is present, can be considered.

TAKE HOME MESSAGE

Prevention plays a key-role in IE especially for high risk population like patients with surgical or transcatheter prosthetic valves, post cardiac valve repair or those who has an uncorrected or surgically corrected congenital heart defect.

The Endocarditis Team of an experienced Valve Center plays the pivotal role in the management of IE patients. Its role is that important that an efficient Infective Multidisciplary Team can improve the clinical outcomes.

IE management is patient based and is comprehensive with the involvement of all the figures surrounding the patient including family and caregivers.

Optimal timing for surgery is still debated, but in absence of hemorrhagic stroke early surgery probably provides better outcomes. In the decision making process for offering surgery after neurological complication the residual quality of life plays a major role. The decision of not offering surgery when indicated should be made in the setting of an Endocarditis Team.

As a valve surgeon I do always remember which is my role in taking care of IE:

We, as surgeons, are taking care of the mechanical complications of IE like embolic risk, valve dysfunction and extension of the infective process to the heart. The real weapon against IE is the antimicrobial therapy. We avoid the disease's progression and restore the heart function.

For a deeper insight follow the link to the full ECS 2023 Guidelines for the management of infective endocarditis here.

Tommaso Hinna Danesi, MD

Section Chief Valve Surgery

Endoscopic Valvular Program Director

Brigham and Women's Hospital

Boston, MA