eComment. Early surgery for patients with uncomplicated prosthetic valve endocarditis

Attaran et al. [1] are to be commended for trying to answer an important question that recurrently arises in clinical practice: do all patients with prosthetic valve endocarditis (PVE) need surgery? The authors concluded after reviewing the relevant literature that redo surgery is warranted especially in case of complicated PVE, or when the culprit organism is Staphylococcus aureus. We entirely agree with their opinion and would like to add a brief comment concerning the timing of surgery in patients with uncomplicated PVE.

Despite advances in medical and surgical care interventions, PVE remains a diagnostic and therapeutic challenge. PVE accounts for 10-30% of all cases of infective endocarditis [2], with the International Collaboration on Endocarditis, the largest registry of patients with endocarditis, reporting a PVE incidence of 20% [3]. Furthermore, the proportion of infective endocarditis cases undergoing surgery ranges from 28-42% as shown in a recent meta-analysis [4]. Unfortunately, PVE still carries a high mortality risk ranging from 20-80% of affected patients [2]. Therapeutic strategies for PVE are not backed by evidence-based recommendations. Although several retrospective studies showed that surgical intervention is indicated in cases of PVE with severe prosthetic dysfunction, heart failure, abscess formation and early staphylococcal infection, no randomized trials have been performed to examine the role of valve surgery in the management of PVE.

There are no clear recommendations regarding the indication for surgery in PVE patients with uncomplicated large vegetations. Indeed, a recently published study tried to find an answer, albeit in patients with native valve endocarditis. The EASE study (Early Surgery versus Conventional Treatment in Infective Endocarditis) is a randomized control trial involving patients with native infective endocarditis, who were candidates for both early surgery and conventional treatment at two Korean medical centres [5]. They randomized 76 patients with vegetations larger than 10 mm, and severe valve dysfunction and assigned them to surgery within 48 hours after enrolment (early surgery) or to antibiotic therapy (conventional treatment). The primary end point was a composite of embolic events or death within 6 weeks after randomization. Early surgery prevented additional embolic events without increasing mortality, whereas 20% in the conventional treatment group had additional embolic events.

Postponing the surgery in this patient population on the assumption that operating on them is too risky and challenging, exposes these patients to the hazard of further destruction of cardiac tissue as well as to the potential development of heart failure and embolic events, and might also render those patients ineligible for surgery due to complications of the disease or its treatment. Further randomized trials are warranted to refine the indications for and timing of surgery especially in patients with uncomplicated PVE.

Conflict of interest: none declared