Clinical outcome and echocardiographic findings of native and prosthetic valve endocarditis in the 1990s

Prosthetic valve endocarditis is considered to be associatedwith a more severe prognosis than native valve endocarditis.Among other factors, inappropriate visualization of vegetationsin prosthetic valve endocarditis by transthoracic echocardiographyis responsible for this observation. Since the introductionof transoesophageal echocardiography into clinical practicethe diagnostic sensitivity and specificity of the detectionof vegetations located on prosthetic valves have been enhanced.Therefore we aimed to determine and compare the prognosis ofprosthetic valve endocarditis and native valve endocarditisin the era of this improved diagnostic approach. One hundred and six episodes of infective endocarditis in 104patients were seen at our institution between 1989 and 1993.Eighty patients (77%) had native valve endocarditis and 24 (23%)had late prosthetic valve endocarditis. In the latter grouptwo patients had recurrent infective endocarditis. Patientswith prosthetic valve endocarditis were older (mean age 64 vs54 years in native valve endocarditis; P<0.00l) and the majoritywas female (62% vs 38% in native valve endocarditis; P<0.001In prosthetic valve endocarditis, infection of a valve in themitral position predominated (65% vs 30% in native valve endocarditis;P<0.0l), whereas in native valve endocarditis more than halfthe cases had isolated aortic valve endocarditis (51% vs 27%in prosthetic valve endocarditis; P<0.01). In prostheticvalve endocarditis more cases were caused by Staphylococcusaureus (31% vs 14% in native valve endocarditis; P<0.08),whereas in native valve endocarditis the most frequent organismswere streptococci (29% vs l9% in prosthetic valve endocarditis;P<0.12). Differences in the clinical features of native valveendocarditis and prosthetic valve endocarditis could not befound except for a higher rate of embolism in native valve endocarditis(40% vs l9% in prosthetic valve endocarditis; P<0.05). Vegetationscould be detected by transthoracic echocardiography more frequentlyin native valve endocarditis (71% vs 15% in prosthetic valveendocarditis; P<0.0001). Transoesophageal echocardiographyvisualized vegetations in 95% of the episodes of native valveendocarditis and in 80% of the episodes of prosthetic valveendocarditis (P<0.09). Thus, the diagnostic gain by transoesophagealechocardiography was greatest in prosthetic valve endocarditis.Patients with native valve endocarditis had significantly largervegetations than patients with prosthetic valve endocarditis(P<0.05 for length, P<0.00l for width). The median timeto diagnosis was similar in native valve endocarditis and prostheticvalve endocarditis (31 vs 28 days). Surgery was performed in 74% of patients with native valve endocarditisand in 58% of those with prosthetic valve endocarditis; themedian time delay between the diagnosis of infective endocarditisand surgery tended to be shorter in prosthetic valve endocarditisthan in native valve endocarditis (45 vs 60 days). The in-hospitalmortality and the mortality during a follow-up of 22±10 months did not significantly differ between native valveendocarditis and prosthetic valve endocarditis (21% vs 17% 28%vs 25%). In summary in the era of transoesophageal echocardiography,late prosthetic valve endocarditis does not seem to carry aworse prognosis than native valve endocarditis. This can beattributed in part to the improved diagnostic accuracy achievedby transoesophageal echocardiography leading to comparable diagnosticlatency periods in both patient groups. Finally, better characterizationof vegetations on prosthetic valves by transoesophageal echocardiographyallows early lifesaving surgery in patients with prostheticvalve endocarditis.     

Highly aggressive early prosthetic endocarditis by S. epidermidis

Prosthetic valve endocarditis is considered to be 15% of all infectious endocarditis in developed countries, more frequently during the first 45 days after surgery. Between 45 and 60% of patients with prosthetic valve endocarditis present periannular involve. The aortic valve injury and early symptoms onset after surgery are related with a higher power of aggressive prosthetic endocarditis invasion. We present the case of a patient affected with early aortic prosthetic valve endocarditis by S. epidermidis with a high aggressive and proliferating course, accompanied by fistula to left atrial, severe aortic regurgitation and left atrial roof rupture detected at the time of surgery, along with interventricular membranous septal defect.     

Prosthetic valve endocarditis caused by Gemella sanguinis: a consequence of persistent dental infection

Late prosthetic valve endocarditis is usually caused by streptococci, staphylococci, gram-negative bacilli and candida. The authors report the first case of prosthetic valve endocarditis caused by Gemella sanguinis. The patient's risk factors for the development of Gemella endocarditis were the persistent severe dental caries and the presence of prosthetic valves. The patient required surgical replacement of the infected valve but had a good outcome with preservation of cardiac and valvular function. Evaluation and treatment of the persistent dental infection before initial valvular surgery may have prevented secondary infection of the prosthetic valve.     

Fungal endocarditis caused by Pseudallescheria (Petriellidium) boydii in an intravenous drug abuser

We present a case of fungal endocarditis in a 42-year-old man with a history of intravenous drug abuse who required aortic valve replacement for severe aortic insufficiency. Cultures of the resected valve grew Pseudallescheria boydii. The patient subsequently developed persistent endocarditis of the prosthetic valve with systemic embolism. At autopsy, cultures of the prosthetic valve grew Monosporium apiospermum, an anamorph of Pseudallescheria boydii. Although fungal endocarditis is not uncommon in intravenous drug abusers, endocarditis caused by Pseudallescheria boydii is rare. It has been reported in only three other instances, and under circumstances that were different from ours.     

Propionibacterium acnes prosthetic valve endocarditis: a case of severe aortic insufficiency.

Propionibacterium acnes rarely causes systemic disease. Few cases of P. acnes endocarditis have been reported. This report describes a 63-year-old man who presented with severe congestive heart failure. He had prosthetic valve endocarditis which resulted in severe acute aortic insufficiency. During surgery he was found to have complete disruption of the aorta and left ventricle with a false aneurysm encompassing the circumference of the aortic annulus. Cultures of the valve grew P. acnes. Thus, although P. acnes is a rare cause of endocarditis, it may pursue a very aggressive course, especially in the setting of a prosthetic valve.     

Prosthetic valve endocarditis in a multicenter registry of Chinese patients

We evaluated the clinical outcomes of prosthetic valve endocarditis in 2 major tertiary referral centers in Hong Kong. The study population comprised 80 consecutive Chinese patients who fulfilled the modified Duke criteria for prosthetic valve endocarditis from March 2000 to June 2007. The major clinical endpoints analyzed were hospital mortality, need for valve surgery, and relapse of prosthetic endocarditis. The mean age at presentation was 56 ± 13 years, with a slight male preponderance. There were 76 (95%) patients with involvement of a mechanical prosthesis; the majority (69%) had late prosthetic endocarditis. Major hospital complications occurred in 49 (61%) patients. The overall hospital mortality was 28% (22 patients). Thirty-four (42%) patients required valve surgery during index hospitalization, of whom 5 (15%) died due to uncontrolled sepsis. Factors associated with hospital mortality were older age at presentation, Staphylococcus aureus infection, embolic events, severe heart failure, valve surgery, and any major complication. On multivariate analysis, severe heart failure was the only independent predictor of hospital death. Among the 58 hospital survivors followed up for a mean of 48 ± 31 months, 6 (10%) developed late complications related to prosthetic valve endocarditis, with 5 documented cases of relapse.     

Mitral valve replacement for mitral stenosis caused by Libman-Sacks endocarditis.

A women who developed mitral stenosis from Libman-Sacks endocarditis is described. The mitral valve was replaced by a Starr-Edwards prosthesis. One year later, despite her being maintained on steroids and azathioprine, the verrucous endocarditis progressed to cause sudden, severe dysfunction of the prosthetic valve.     

Predictors of hospital mortality in 186 cases of active infective endocarditis treated in a tertiary medical center (1992-2001)

INTRODUCTION AND OBJECTIVES: The aim of this study was to describe the predictors of hospital mortality found in patients admitted for infective endocarditis (IE) to a cardiovascular surgery ward.Patients and method. Prospective study of 186 patients with IE treated in our hospital between 1992 and 2001. RESULTS: One hundred fourteen patients (61.3%) had native valve endocarditis and 72 (38.7%) had prosthetic valve endocarditis (early in 28 patients [up to 12 months after surgery] and late in 44 [later than 12 months]). Blood cultures were positive in 82%. The predominant organism was Streptococcus viridans (36%) in native valve endocarditis and Staphylococcus aureus (33%) in prosthetic valve endocarditis. The hospital mortality was 22.6%. Severe sepsis (4.8%) produced a high mortality rate (88%) and was caused by Staphylococcus aureus in 60%. One hundred nineteen patients (64%) required surgery, 79 (66.4%) of them urgently. Negative blood cultures predicted need for surgery in native valve endocarditis (p < 0.05). The surgical mortality was 21.8% and was related to NYHA III-IV class (p = 0.014) and emergency surgery (p = 0.009) in patients with native valve endocarditis. This last factor also predicted higher surgical mortality in patients with early prosthetic valve endocarditis (p < 0.001). CONCLUSIONS. The hospital mortality of this group of patients with infective endocarditis treated in a tertiary medical center was high. The presence of severe sepsis, although infrequent, had a somber prognosis. Severe heart failure in native valve endocarditis and urgent surgery in native and prosthetic valve endocarditis increased surgical mortality.     

Mitral valve replacement for mitral stenosis caused by Libman-Sacks endocarditis.

A women who developed mitral stenosis from Libman-Sacks endocarditis is described. The mitral valve was replaced by a Starr-Edwards prosthesis. One year later, despite her being maintained on steroids and azathioprine, the verrucous endocarditis progressed to cause sudden, severe dysfunction of the prosthetic valve.     

Prosthetic valve endocarditis: Clinicopathologic analysis of 22 necropsy patients with comparison of observations in 74 necropsy patients with active infective endocarditis involving natural left-sided cardiac valves

Clinical and morphologic features are described in 22 necropsy patients with endocarditis involving rigid-framed prosthetic valves: aortic in 15 patients and mitral in 7. The interval from valve replacement to onset of symptoms of prosthetic valve endocarditis was less than 2 months in 8 patients and longer than 2 months in 14 patients. The most frequent infecting organism was the Staphylococcus (13 patients). In each of the 22 patients the infection was located behind the site of attachment of the prosthesis to the valve ring, and the infection spread to adjacent structures in 13 patients, 11 of whom had aortic prostheses. Prosthetic detachment causing severe regurgitation occurred in 12 ot the 15 patients with an infected aortic valve prosthesis, and in 2 of the 7 with an infected mitral valve prosthesis. Prosthetic obstruction by vegetative material occurred in 5 of 7 patients with prosthetic mitral infection and in only 1 of 15 with prosthetic aortic infection. High degrees of conduction defects developed in seven patients with aortic prosthetic valve endocarditis: complete heart block in five, and complete left bundle branch block in two.Comparison of observations in the 22 patients with prosthetic valve endocarditis with those in 74 patients with active infective endocarditis involving natural left-sided cardiac valves revealed significant (P < 0.05) differences in the percent with ring abscess, hemodynamic consequences of the endocarditis (valve stenosis), frequency of Staphylococcus as the causative organism and percent with complete heart block or left bundle branch block. No significant differences were observed between the two groups when comparing age, sex, type of underlying valve disease or frequency of organ infarcts or splenomegaly.     

Risk of endocarditis among patients with prosthetic valves and Staphylococcus aureus bacteremia

PURPOSE: Staphylococcus aureus is a common cause of bacteremia and of native valve infective endocarditis. However, the risk of endocarditis in patients with a prosthetic valve who develop S. aureus bacteremia is unclear. The aim of this study was to define the risk of prosthetic valve endocarditis in patients with S. aureus bacteremia. SUBJECTS AND METHODS: All patients with a prosthetic valve or ring who developed S. aureus bacteremia during the 94-month study period were prospectively evaluated. The modified Duke criteria were used for the diagnosis of endocarditis. Patients were followed up for 12 weeks after the initial diagnosis of S. aureus bacteremia. RESULTS: The overall rate of definite prosthetic valve endocarditis among the study patients was 26/51 (51%). The risk of endocarditis was similar in patients with late (>or=12 months after valve implantation) vs. early S. aureus bacteremia (<12 months after prosthetic valve implantation) (50% vs. 52%, P=1.0), mitral vs. aortic prostheses (62% vs. 48%, P=0.24), and mechanical vs. bioprosthetic valves (62% vs. 44%, P=0.29). The 12-week mortality was higher among patients with definite vs. possible endocarditis (62% vs. 28%, P=0.019). CONCLUSION: In this investigation, approximately half of all patients with prosthetic valves who developed S. aureus bacteremia had definite endocarditis. The risk of endocarditis was independent of the type, location, or age of the prosthetic valve. The mortality of prosthetic valve endocarditis is high. All patients with a prosthetic valve who develop S. aureus bacteremia should be aggressively screened and followed for endocarditis.     

Outcome of aortic homograft implantation in 24 cases of severe infective endocarditis

The objective of the study was to evaluate the results of treatment of severe aortic endocarditis with an aortic homograft (an aortic valve and root from a donor) in combination with antibiotic therapy. 24 patients with either aortic prosthetic valve endocarditis (n=16) or severe aortic native valve endocarditis (n=8) with destruction of 1 or more cusps, paravalvular abscess formation and/or cardiac fistulas caused by aggressive bacteria, underwent surgery in 1997-2006. Staphylococcal species were the most common pathogens followed by streptococci. Intravenous antibiotic therapy was started before surgery and continued for at least 4-6 weeks. Three patients with prosthetic valve endocarditis died within the first 24 h after surgery from heart failure. Two of these patients required an additional implantation of a mitral valve prosthesis. Five patients died from non-cardiac causes within 1-7 y of surgery. Within the follow-up period no patients had relapse of endocarditis, and only 1 episode of recurrent endocarditis in an intravenous drug abuser was registered. In conclusion, an aortic homograft in combination with intravenous antibiotics is an excellent option for treatment of severe aortic endocarditis.     

Surgical therapy of infective endocarditis

Therapy of infective endocarditis (IE) remains a particular challenge due to a relative high morbidity and mortality. Cardiac surgery is established as a cornerstone in therapy for native valve endocarditis (NVE) as well as for prosthetic valve endocarditis (PVE) and is required in 30% of patients with active IE. The basic aim of surgery in IE is the radical debridement of infected tissue and reconstruction of valve function either by reconstructive valve surgery or valve replacement. Indication for surgery depends on several clinical variables, the main indication remains heart failure due to severe heart valve defects or prosthetic valve dysfunction. Surgical therapy of NVE can be performed with good clinical results in the early and late follow-up. Surgical therapy of PVE is still associated with quite high mortality up to 80% in some risk groups. This indicates the particular importance of focus evaluation and antibiotic prophylaxis after primary surgery for infective endocarditis.     

First report of prosthetic mitral valve endocarditis due to Corynebacterium striatum: Successful medical treatment. Case report and literature review

A rare case of prosthetic mitral valve endocarditis due to Corynebacterium striatum, treated medically, is reported. While this organism has been described in a few cases of native valve endocarditis, only two cases of prosthetic aortic valve endocarditis have been reported. We herewith report the first case of successful medical treatment of prosthetic mitral valve endocarditis due to C. striatum, emphasizing the complicated clinical course and reviewing the literature regarding diagnosis and therapeutical approach.     

Prosthetic valve endocarditis due to small-colony staphylococcal variants

Although Staphylococcus epidermidis is a major cause of prosthetic valve endocarditis, little is known about the pathogenesis of this disease. In one case described herein, small-colony variant forms of S. epidermidis were isolated from clinical specimens obtained from a patient with prosthetic valve endocarditis. Data from the rat model of experimental endocarditis provide further evidence that small-colony variants may be operative in the production of prosthetic valve infection. Moreover, a review of the literature indicates that small-colony variants could account for the subtle clinical course after prolonged dormant infection that characterizes S. epidermidis prosthetic valve endocarditis. It is therefore hypothesized that small-colony variants of S. epidermidis may play a role in the pathogenesis of prosthetic valve endocarditis.     

Staphylococcus capitis prosthetic valve endocarditis: report of two rare cases and review of literature

Staphylococcus epidermidis is the most common organism associated with prosthetic valve endocarditis. Staphylococcus capitis, a coagulase-negative Staphylococcus, is a rare cause of endocarditis. We report two cases of S.capitis prosthetic valve endocarditis, both involving prosthetic aortic valve and complicated by aortic root abscess. We also review the literature for this rare condition caused by this rare organism.     

Importancia clínica de la insuficiencia cardiaca congestiva en la endocarditis protésica. Estudio multicéntrico de 257 pacientes

Introduction and objectives

There have been no studies conducted in the past that focus on the significance of congestive heart failure in patients with prosthetic valve endocarditis. We studied the incidence of congestive heart failure in patients with prosthetic valve endocarditis and analyzed its profile. In this study, we addressed the prognostic significance of heart failure in patients with prosthetic valve endocarditis and analyzed its outcome based on chosen therapeutic strategies.

Methods

A total of 639 episodes of definite left-sided endocarditis were prospectively enrolled. Of them, 257 were prosthetic. Of the 257 episodes, 145 (56%) were diagnosed with heart failure. We compared the profiles of patients with prosthetic valve endocarditis based on the presence of heart failure, and performed a multivariate logistic regression model to establish the prognostic significance of heart failure in patients with prosthetic valve endocarditis and identified the prognostic factors of in-hospital mortality in these patients.

Results

Persistent infection (odds ratio=3.6; 95% confidence interval, 1.9-6.9) and heart failure (odds ratio=3; 95% confidence interval, 1.5-5.8) are the strongest predictive factors of in-hospital mortality in patients with prosthetic valve endocarditis. The short-term determinants of prognosis in patients with prosthetic valve endocarditis and heart failure are persistent infection (odds ratio=2.8; 95% confidence interval, 1.2-6.5), aortic involvement (odds ratio=2.5; 95% confidence interval, 1.1-5.8), abscess (odds ratio=3.6; 95% confidence interval, 1.4-9.5), diabetes mellitus (odds ratio=2.9; 95% confidence interval, 1.1-7.7), and cardiac surgery (odds ratio=0,2; 95% confidence interval, 0,1-0,5).

Conclusions

The incidence of heart failure in patients with prosthetic valve endocarditis is very high. Heart failure increases the risk of in-hospital mortality by threefold in patients with prosthetic valve endocarditis. Persistent infection, aortic involvement, abscess, and diabetes mellitus are the independent risk factors associated with mortality in patients with prosthetic valve endocarditis and heart failure; however, cardiac surgery is shown to decrease mortality in these patients.Full English text available from:www.revespcardiol.org/en     

Reconstruction of the Fibrous Trigone

A 48-year-old man with a history of infective endocarditis and severe aortic regurgitation had undergone prosthetic aortic valve replacement at another institution. Two months later, the patient developed prosthetic valve endocarditis with an aortic root abscess and an aorto–left atrial periprosthetic valvular fistula through the detached posterior annulus of the mitral valve. We repaired the fistula by constructing a fibrous trigone made of bovine pericardium. We also replaced the prosthetic aortic valve with another prosthetic valve, while protecting the native mitral valve.Key words: Aortic valve replacement, endocarditis/complications/surgery, fistula/etiology/surgery, heart valve prosthesis/adverse effects, mitral valve repair, prosthesis-related infections, reoperationThe incidence of prosthetic valve endocarditis (PVE) within 12 months after heart valve replacement is between 1% and 3.1%.^1,2 In the largest PVE case series to date, 20.1% of the cases of infective endocarditis were due to PVE³—a severe and life-threatening infection, particularly when accompanied by a paraprosthetic abscess and progression of fistulous communication.Aorto–left atrial fistula, a rare complication of PVE, is surgically challenging. We report the successful surgical repair of an aorto–left atrial periprosthetic valvular fistula in concordance with re-replacement of the aortic valve, while protecting the native mitral valve.     

Corynebacterium striatum first reported case of prosthetic valve endocarditis

We describe the case of a prosthetic valve endocarditis in a 72-year-old woman. Corynebacterium striatum was isolated in the blood samples. This organism has been described in a few cases of native valve endocarditis, but this is the first case reported of prosthetic valve endocarditis.     

Prosthetic Valve Endocarditis with Valvular Obstruction after Transcatheter Aortic Valve Replacement

Patients with severe aortic stenosis who are at high risk for open-heart surgery might be candidates for transcatheter aortic valve replacement (TAVR). To our knowledge, this is the first report of Streptococcus viridans endocarditis that caused prosthetic valve obstruction after TAVR.A 77-year-old man who had undergone TAVR 17 months earlier was admitted because of evidence of prosthetic valve endocarditis. A transthoracic echocardiogram revealed a substantial increase in the transvalvular peak gradient and mean gradient in comparison with an echocardiogram of 7 months earlier. A transesophageal echocardiogram showed a 1.5-cm vegetation obstructing the valve. Blood cultures yielded penicillin-sensitive S. viridans. The patient was hemodynamically stable and was initially treated with vancomycin because of his previous penicillin allergy. Subsequent therapy with levofloxacin, oral penicillin (after a negative penicillin skin test), and intravenous penicillin eliminated the symptoms of the infection.Transcatheter aortic valve replacement is a relatively new procedure, and sequelae are still being discovered. We recommend that physicians consider obstructive endocarditis as one of these.