From the Guidelines
PVE in endocarditis stands for Prosthetic Valve Endocarditis, which is an infection of a prosthetic heart valve, and its management is guided by the 2015 ESC guidelines for the management of infective endocarditis 1.
Definition and Classification
PVE occurs when microorganisms, typically bacteria, colonize and infect the artificial valve material or surrounding tissue. It is classified as early (occurring within one year of valve implantation) or late (occurring after one year). Early PVE is usually acquired during surgery or in the immediate postoperative period, commonly caused by Staphylococcus epidermidis, Staphylococcus aureus, or gram-negative bacteria, as noted in the 2015 ESC guidelines 1.
Microbiology and Diagnosis
Late PVE resembles native valve endocarditis in its microbiology, with streptococci, enterococci, and staphylococci being common pathogens 1. The diagnosis of PVE is more difficult than for native valve endocarditis, and it represents 20% of all cases of IE, with an increasing incidence 1.
Treatment and Management
Treatment typically requires prolonged intravenous antibiotics (usually 6 weeks) tailored to the specific pathogen, often with a combination of antibiotics. Surgical intervention is frequently necessary, especially in cases of valve dysfunction, heart failure, persistent infection despite antibiotics, or large vegetations with embolic risk, as indicated by the guidelines 1. Prevention includes appropriate antibiotic prophylaxis for dental and other procedures in high-risk patients with prosthetic valves.
Key Considerations
PVE is more difficult to diagnose and treat than native valve endocarditis, with higher mortality rates (20-40%) 1. Complicated PVE and staphylococcal PVE are associated with a worse prognosis if treated without surgery, and these forms of PVE must be managed aggressively 1. Patients with uncomplicated, non-staphylococcal late PVE can be managed conservatively with close follow-up 1.
Indications for Surgery
The indications for surgery in PVE include heart failure, uncontrolled infection, and prevention of embolism, as outlined in the 2015 ESC guidelines 1, which provides a comprehensive approach to the management of PVE.
- Heart failure: Emergency surgery is indicated for aortic or mitral PVE with severe acute regurgitation, obstruction, or fistula causing refractory pulmonary edema or cardiogenic shock 1.
- Uncontrolled infection: Urgent surgery is indicated for locally uncontrolled infection, infection caused by fungi or multiresistant organisms, and persisting positive blood cultures despite appropriate antibiotic therapy and adequate control of septic metastatic foci 1.
- Prevention of embolism: Urgent surgery is indicated for aortic or mitral PVE with persistent vegetations >10 mm after one or more embolic episodes despite appropriate antibiotic therapy 1.
From the Research
Definition and Incidence of Prosthetic Valve Endocarditis (PVE)
- Prosthetic valve endocarditis (PVE) is a serious complication of valve replacement surgery, associated with high mortality during early and midterm follow-up 2.
- The incidence of PVE is increasing and accounts for 20-30% of all infective endocarditis episodes 2.
- PVE is a rare and serious complication of valve replacement, associated with high morbidity and mortality, which significantly differs from native valve endocarditis (NVE) 3.
Causes and Risk Factors of PVE
- Staphylococci (both Staphylococcus aureus and coagulase-negative Staphylococcus) have emerged as the most common cause of PVE and are associated with a severe prognosis 2.
- Early PVE, comorbidity, severe heart failure, and new prosthetic dehiscence are predictors of mortality 2.
- The early character of PVE, heart failure, uncontrolled infection, staphylococcal endocarditis, and dehiscence of prosthesis with significant regurgitation are also predictors of mortality 4.
Diagnosis and Treatment of PVE
- Diagnosis of PVE may often be difficult due to its complications and extracardiac manifestations, requiring a comprehensive assessment of clinical, echocardiographic, and laboratory data 2.
- Transesophageal echocardiographic examination remains the widely used imaging technique in PVE diagnosis, but additional techniques such as computed tomography (CT) and 18F-fluodeoxyglucose positron emission tomography/CT are often necessary 3.
- Surgical treatment is associated with significantly lower hazard of death in patients with PVE, and is recommended for patients with persistent fever, embolic complications, valve dehiscence, intracardial abscess, heart failure, as well as staphylococcal and fungal PVE 4, 5.
- Combined medical and surgical treatment is recommended for PVE, and surgical treatment is associated with a large survival benefit in PVE 4, 5.