Q fever endocarditis: the Mayo Clinic experience

OBJECTIVES: To report the Mayo Clinic experience of Q fever endocarditis. BACKGROUND: Q fever endocarditis is rare in North America with few case reports in the literature. The Centers for Disease Control lists Q fever as a reportable illness but does not differentiate endocarditis as a syndrome in its database. METHODS: A search of the database for elevated Q fever IgG serology at our institution was conducted from December 1980 to December 2005. Patients with elevated serologies were retrospectively identified and their medical records were reviewed to determine which cases met criteria for a diagnosis of endocarditis. RESULTS: Eight patients with elevated serology were identified. One case failed to meet criteria and was therefore excluded. All patients presented with fever and had previously diagnosed valvular disease. Only 3 patients had valvular vegetations on transesophageal echocardiography. All 7 patients were treated with antimicrobial therapy, which was not uniform. Six required surgical intervention on the affected valves, and 2 required multiple valve surgeries. Follow-up ranged from 1 to 17 years. CONCLUSIONS: Q fever endocarditis is a rare disease in the United States, where no reliable reporting exists. Q fever endocarditis involves underlying abnormal native valves or prosthetic valves. Vegetations are small or absent. Relapses are common. Surgeries are common adding to morbidity and cost. The chronicity of the syndrome and its high morbidity mandate an increased awareness of the condition in patients with culture-negative endocarditis or unexplained perivalvular leaks detected by echocardiography. Appropriate diagnosis and tailored treatment are likely to reduce the need for repeat surgeries.     

Whipple's endocarditis: review of the literature and comparisons with Q fever, Bartonella infection, and blood culture-positive endocarditis.

Whipple's disease is a systemic infection sometimes associated with cardiac manifestations. Recently, there has been an increase in the number of reported cases of Whipple's endocarditis. The purpose of our study was to describe this entity. Data from 35 well-described cases of Whipple's endocarditis were collected and compared with those of blood culture-positive endocarditis, Q fever endocarditis, and Bartonella endocarditis. Some patients with generalized Whipple's disease presented with cardiac involvement, among other symptoms. Others presented with a nonspecific, blood culture-negative endocarditis with no associated symptoms. In comparison with cases of endocarditis due to other causes, congestive heart failure, fever, and previous valvular disease were less frequently observed in the cases of Whipple's endocarditis. Without examination of the excised valves, the diagnosis of infective endocarditis could not have been confirmed in most cases. Treatment is not well established. Whipple's endocarditis is a specific entity involving minor inflammatory reactions and negative blood cultures, and its incidence is probably underestimated.     

The value of follow-up after acute Q fever infection

This is a case report of a 53-year-old woman involved in an outbreak of Q fever, in whom Q fever endocarditis was diagnosed 18 months after acute Q fever infection. At the time of diagnosis, she was completely asymptomatic and without screening for chronic Q fever, this severe potentially life-threatening infection would probably not have been recognised until significant valvular destruction had taken place. Early diagnosis enabled prompt, potentially curative medical treatment to start without the need for valvular heart surgery. The authors advocate that serological monitoring should be carried out every 4 months for a period of 2 years after acute Q fever and patients with high phase 1 IgG titres (>800) be investigated further and/or followed more closely depending on the clinical scenario. The case report also discusses the use of complement fixation testing in the diagnosis of Q fever endocarditis. The authors recommend that in cases of culture negative endocarditis, a single negative complement fixation test is not sufficient to exclude the diagnosis of Q fever endocarditis. Micro-immunofluorescence or repeat complement fixation testing is recommended when Q fever endocarditis is suspected clinically.     

Clinical, echocardiographic and prognostic profile of Streptococcus viridans left-sided endocarditis

INTRODUCTION AND OBJECTIVES: Published case series on Streptococcus viridans endocarditis are scarce and outdated. The aims of our study were multiple: to analyze the profile of the Streptococcus viridans endocarditis, to compare it with other types of left-sided endocarditis and with cases caused by Staphylococcus aureus, and to determine predictors of poor outcome in Streptococcus viridans endocarditis. PATIENTS AND METHOD: We analyzed 441 episodes of endocarditis: 330 left-sided and 54 caused by Streptococcus viridans (16%). We compared the 54 cases due to Streptococcus viridans with the remaining cases of left-sided endocarditis in our series, and also with cases caused by Staphylococcus aureus. We also analyzed the predictors of death and urgent surgery in Streptococcus viridans endocarditis. RESULTS: Left-sided endocarditis due to Streptococcus viridans led to a similar degree of valvular destruction, showed acute onset less frequently, and led to less renal failure, septic shock and mortality than the remaining cases of left-sided endocarditis in our series. The same differences were found in comparison to Streptococcus viridans endocarditis. Prognostic factors for Streptococcus viridans left-sided endocarditis were heart failure and periannular complications. CONCLUSIONS: Although Streptococcus viridans is a nonaggressive microorganism, valvular destruction is similar to that caused by other pathogens when it causes left-sided endocarditis. Nonetheless its prognosis is better, a feature which may be related to the fact that the systemic infectious syndrome can be treated more effectively. Prognostic factors in left-sided endocarditis due to Streptococcus viridans are heart failure and periannular complications.     

Surgery of bacterial aortic insufficiency. Indications and results

Seventy nine patients were operated for aortic regurgitation due to bacterial endocarditis confirmed anatomically at surgery between 1968 and 1984. They were classified into 3 groups according to the stage of endocarditis at the time of operation: progressive endocarditis (21 cases), recent endocarditis (39 cases) and late endocarditis (19 cases). The patients were adults (21 to 70 years) and predominantly male (82 p. 100). Previous valvular disease was found in 38 cases, bicuspid aortic valves were found in 21 cases. Most of the patients operated early (recent progressive endocarditis) had cardiac failure and the surgical indication was nearly always poor haemodynamic tolerance. In addition, this indication was also retained in late forms of the disease in patients usually panci-symptomatic in the presence of signs of increasing left ventricular dysfunction. The aortic lesion was the only pathology in 55 cases and was associated with periannular abscess in 8 cases, septal abscess in 5 cases including one with septal perforation, and mitral endocarditis in 12 cases. Seven patients died during surgery, in low output states in 6 cases (global mortality 8.9 p. 100). The 72 survivors were followed up for an average period of 5 years (4 to 168 months); three patients were lost to follow-up. The actuarial survival rate including the operative mortality was 77 p. 100 at 5 years and 64.6 p. 100 at 10 years. Valve dehiscence was common (52 p. 100); although the perivalvular leak was usually small, in 11 cases it was quite severe and 7 patients had to be reoperated. An excellent functional result was observed in 30 cases, especially in those patients operated early.     

Coxiella burnetii endocarditis: long-term clinical course in 20 patients

INTRODUCTION AND OBJECTIVES: Coxiella burnetii is a causative agent of increasingly frequent subacute infective endocarditis, and is associated with elevated morbimortality. Our aim in the present study was to assess the clinical, serological and therapeutic long-term evolution of 20 patients with Coxiella burnetii endocarditis. METHODS: Twenty patients (13 male and 7 female, age 42 +/- 10 years) admitted between 1982 and 1996 were retrospectively studied. All of them fulfilled the Duke criteria modified by Raoult for Q fever endocarditis. RESULTS: Endocarditis involved prosthetic and native valves in 14 and 6 patients, respectively. All patients except one received antibiotic treatment. Patients treated with doxycycline in monotherapy showed worse evolution than those treated with doxycycline in combination with other antibiotics. Valve replacement was performed in 15 patients, due to prosthetic dysfunction in most of them. The overall mortality was 40% (8 patients). At follow-up of 74 months (range 19-156) (mean 74 +/- 47) all patients showed persistent high levels of phase I antibodies. At follow-up of 15 to 65 months (32 +/- 30) antibiotic treatment was suspended in five patients because they were asymptomatic and without microbiologic findings of valvular endocarditis. CONCLUSIONS: Q fever endocarditis was associated with severe complications, which often required valve replacement. All patients showed persistent high serological titers of Coxiella burnetii endocarditis without other signs of active infection. This finding raises the issue of suspending antibiotic treatment in patients with negative microbiologic findings and questions the persistence of abnormal serology as a monitor of treatment efficacy.     

Prosthetic valve endocarditis due to Coxiella burnetii: six cases]

PURPOSE: Prosthetic valve endocarditis is a dangerous complication of valvular surgery (3-6%). Among involved pathogens, Coxiella burnetii is an occasional agent, though isolated with increasing frequency. We report our experience with this peculiar endocarditis and lay stress on specific diagnostic and therapeutic difficulties. METHODS: Between 1990 and 1995, six patients retrospectively met the diagnosis criteria for definite endocarditis due to Coxiella burnetii. RESULTS: Five Algerian men and one French woman presented with prosthetic valve endocarditis with negative blood cultures (on bioprosthesis: four cases, on mechanical valve: two cases). The main clinical and biological feature was febrile congestive heart failure with hepatomegaly, splenomegaly, hepatic and renal abnormalities, inflammatory syndrome, hypergammaglobulinemia, anemia and lymphopenia. Serological testing for Coxiella burnetii provided diagnosis in all cases. Echocardiography displayed vegetations in all cases. Valvular replacement was performed in four patients. With antibiotic therapy including doxycycline or/and hydroxychloroquine, quinolones or rifampicine, all patients experienced complete clinical, biological and echographic remission. CONCLUSION: Q fever prosthetic valve endocarditis presents as a systemic disorder occurring in patients with valvular heart disease. From now on, early diagnosis and efficient medical treatment may provide permanent prosthetic sterilization.     

Risks factors and prevention of Q fever endocarditis.

Coxiella burnetii causes acute and chronic Q fever. To evaluate the risk factors of development of chronic endocarditis following Q fever and to assess the best preventive therapy, a retrospective study of patients diagnosed as having Q fever during 1985-2000 was conducted. Twelve patients with acute Q fever who developed endocarditis and 102 patients with Q fever endocarditis were included in the study. When compared to 200 control patients with acute Q fever, preexisting valvular disease (P<10(-7)), especially a prosthetic valve (P=.01), were encountered more often among patients with endocarditis. Among patients with valvular defects, we estimate the risk of developing endocarditis to be 39%. A combination of doxycycline plus hydroxychloroquine was better at preventing the development of endocarditis than doxycycline alone (P=.009). Our results should encourage physicians to detect valvular lesions in patients with acute Q fever and to search for acute Q fever in patients with a valvulopathy and unexplained fever. A proper treatment for such patients and a scheduled follow-up should reduce the risk of developing endocarditis.     

Medium term fate of dura mater valvular bioprostheses

Eighty-two patients have been followed for a mean period of29 months after implantation of dura mater valvular bioprostheses(60 mitral valves, 30 aortic valves and two tricuspid valves).There have been three late deaths, two related to reoperationand one to endocarditis. Severe hemolysis, infective endocarditisand systemic emboli have been recorded twice each. There havebeen 20 instances of valvular dysfunction: 13 cases (15.7%)with intravalvular dysfunction, either proved at surgery (11cases) or suggested by echocardiography (two cases). In fivecases (6%) dysfunction has been due to a perivalvular leak.In two cases the mechanism of dysfunction has not been demonstrated.The most frequent causes of intravalvular dysfunction have beena tear-like rupture of an otherwise normal leaflet (five cases)and extensive valvular calcification (four cases). It is concludedthat the very high rate of intravalvular dysfunction makes duramater valves unsuitable for valvular replacement.     

Prognostic significance of valvular regurgitation in patients with infective endocarditis

PURPOSE: Doppler ultrasound is a sensitive modality for detecting and quantitating valvular regurgitation in patients with infective endocarditis. Because valvular regurgitation leads to heart failure, we evaluated the prognostic significance of Doppler-detected valvular regurgitation in patients with endocarditis who had not yet developed clinical heart failure. PATIENTS AND METHODS: We reviewed the medical records of 65 patients with a clinical diagnosis of infective endocarditis from May 1985 to March 1990. A total of 49 patients were included in the study: 33 patients with native valve endocarditis and 16 patients with prosthetic valve endocarditis. The initial Doppler echocardiogram was examined in these patients to determine the presence and degree of valvular regurgitation. RESULTS: Significant (moderate to severe) valvular regurgitation was detected in 23 (47%) patients. The presence or absence of significant valvular regurgitation did not predict the development of congestive heart failure, the need for surgery, or death (p = NS). The development of congestive heart failure was significantly associated with the need for surgery (p less than 0.0001) and death (p less than 0.05). CONCLUSION: We conclude that the detection of significant valvular regurgitation in patients with infective endocarditis who have not yet developed heart failure is not predictive of future complications nor does the absence of significant valvular regurgitation identify a group of patients with a more favorable prognosis. In our series, patients who developed congestive heart failure had a significantly higher incidence of surgery and death. Therefore, decisions regarding clinical management in patients with infective endocarditis should not be made solely on the presence or absence of echocardiographically detected valvular regurgitation.     

Acalculous cholecystitis: an unusual presentation of acute Q fever masquerading as infectious endocarditis

We report here a patient with acute Q fever-related acalculous cholecystitis, who presented with prolonged fever, valvular abnormalities, and positive serology for Q fever phase 1 antigens, features suggesting chronic Q fever endocarditis. The pathogenesis of this rare presentation of Q fever is discussed.     

Infective endocarditis of native cardiac valves: 22 years' surgical experience

BACKGROUND AND AIM OF THE STUDY: Most previous studies on surgery for endocarditis included cases of both prosthetic and native valve endocarditis (NVE), which clearly differ in their course and prognosis. METHODS: Between February 1979 and July 2000, 199 patients underwent surgical treatment for NVE. The native valve was replaced in 185 patients, and repaired in 14. Correlations between previous heart disease and site of NVE, site and etiology, site and embolism, and etiology and extracardiac infection were analyzed. Viability of echocardiography to identify NVE features was compared with surgical inspection. Risk factors for hospital, late mortality and recurrence were assessed by multivariate analysis, including preoperative, operative and postoperative variables. RESULTS: Streptococci were found in 52 cases (26.1%), mostly spreading from splanchnic (n = 10) and cutaneous (n = 9) infections; Staphylococci were found in 43 cases (21.6%), mostly from cutaneous foci (n = 20). Tricuspid valve endocarditis was due to Staphylococcus sp. in all documented cases (11/15; p <0.001), while Streptococcus sp. predominated in the mitral (p = 0.026) position. Echocardiography was reliable in identifying anatomic features of NVE, except for periannular abscess (13 versus 31 found at surgery; p <0.001). Hospital mortality was 6% (n = 12): preoperative NYHA class IV (p = 0.034) and emergency surgery (p = 0.001) were significant predictors of mortality. Average follow up was 57.2+/-4.4 months and was 96.3% complete. There were 27 late deaths (15%). Actuarial survival was 75.7% at 10 years and 60.3% at 20 years. Low social status (p = 0.022), diabetes mellitus (p = 0.003), fever at time of surgery (p = 0.041) and persistent postoperative fever (p = 0.0002) were predictors for late mortality. Endocarditis recurred in 28 patients (15.5%), with 74.1% freedom at 10 years and 68.7% at 20 years. Drug abuse (p = 0.001), mitral endocarditis (p = 0.002), positive blood cultures (p = 0.0003), homograft implantation (p = 0.0012) and persistent postoperative fever (p <0.0001) were significant predictors for recurrence. CONCLUSION: Preoperative conditions of patients with NVE significantly affect early and long-term outcomes. Prognosis is worsened by delayed diagnosis and operation during the active septic process.     

Human valvular substitutes for the treatment of complex progressive endocarditis. Application to aortic, mitral and tricuspid valves

The aim of this study was to assess the immediate and long-term results of human valvular substitutes (homografts and autografts) in the treatment of complex progressive endocarditis in aortic, mitral and tricuspid valves. Since 1992, 80 patients (64 men, 16 women) aged 44 +/- 16 years (range 15 to 76 years), were treated. In 53 patients, the endocarditis involved native valves, 4 on previously plastified valves, or prosthetic valves in 27 patients. The endocarditis was recurrent 6 patients. The lesions were situated on the aortic valve (N = 59), mitral valve (N = 5), aortic and mitral valves (N = 12), aortic and tricuspid valves (N = 3), mitral and tricuspid valves (N = 1). The peroperative findings confirmed the lesions diagnosed at echocardiography: prosthetic valve dehiscence (27 patients), prosthetic cusp tear (N = 7), vegetations (N = 61), perforations (N = 48), periannular abscess (N = 47), aorto-ventricular discontinuity (N = 12), aorto-mitral discontinuity (N = 7), right ventricular aortic fistula (N = 1), aorto-pulmonary fistula (N = 1), pseudo-aneurysm (N = 1), ventricular septal defect (N = 1). Eighty-six human valvular substitutes were used (double homograft in 6 patients): aortic homograft (N = 63), pulmonary in the aortic position (N = 1), the mitral position (N = 12), of which 8 were in the mitral and 4 in the tricuspid position, pulmonary autograft (N = 10). Ten mitral valve repairs were performed on infected lesions. Associated procedures included mitral valve repair (N = 5), tricuspid valve repair (N = 1) for non-infarcted valve lesions, replacement of the ascending aorta (N = 2), the aortic arch (N = 1), coronary bypass surgery (N = 2) and one nephrectomy. The hospital mortality was 5% (4 patients). The causes of death were: infarction (N = 2), myocardial failure (N = 1) and multiorgan failure (N = 1). Four early reoperations were required for technical problems, none for endocarditis. Seventy-three of the 76 survivors were followed up for 43 +/- 24 months (range 1 to 84 months). Eight patients died during follow-up, but only 1 of cardiac causes (operation for recurrent endocarditis in a drug abuser). Seven operations were performed, 3 for technical problems or structural failure, 4 for recurrent endocarditis. At 5 years' follow-up, the survival was 81 +/- 5%; 88 +/- 6% of patients were free of endocarditis, 77 +/- 6% had no reoperation: no patient had thromboembolic complications. These results show that human valvular substitutes are adapted for the treatment of complex, progressive aortic, mitral and tricuspid valve endocarditis when techniques of valvular repair are no longer feasible.     

Reoperations in valve surgery. Apropos of 194 cases

Between 1970 and 1985, 194 patients underwent one or several reoperations after conservative valvular surgery (Group A) or valvular replacement surgery (Group B). Group A: comprised 141 patients with a previous history of closed heart mitral commissurotomy (114 cases), open heart mitral commissurotomy (20 cases), mitral valvuloplasty (5 cases) or aortic commissurotomy (2 cases) reoperated after an average period of 153 +/- 44 months. At reoperation, prosthetic valve replacement of the previously operated valve was systematic and another valvular procedure was also performed in 66 cases. Hospital mortality was 7.8 p. 100. Mortality was high in patients reoperated in functional Class IV of the NYHA classification, after closed heart mitral commissurotomy performed over 10 years before hand. The global mortality rate was 17 p. 100 (average postoperative follow-up of 70 +/- 44 months). The actuarial 5 year survival rate was 85 +/- 6 p. 100 and the 10 year survival was 70 +/- 13 p. 100; NYHA Class IV cardiac failure was a significant poor prognostic factor (p less than 0.05). The prognosis of reoperation after commissurotomy depended mainly on the interval between the relapse of symptoms and reoperation. Group B: comprised 53 patients with valvular prostheses reoperated after an average period of 58 +/- 41 months. The indications of reoperation were prosthetic valve dysfunction (31 cases), perivalvular leak (5 cases), prosthetic valve thrombosis (6 cases), infective endocarditis (7 cases), haemolysis (1 case) and associated valvular disease (10 cases). Reoperation concerned mechanical prostheses in 26 cases and bioprostheses in 24 cases. It consisted in valvular replacement (51 cases) or reinsertion (2 cases). Eight patients underwent second reoperation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bicuspid aortic valve--A silent danger: analysis of 50 cases of infective endocarditis.

We analyzed 50 cases of bicuspid aortic valve endocarditis in patients who presented to St. Thomas' Hospital from 1970 through 1998. These represented 12.3% of the 408 cases of native valve endocarditis (NVE). All patients were male, and their mean age was 39 years. Forty-five of the 50 cases were pathologically proven; 47 were clinically definite according to the Duke criteria and 49 according to our modifications of the Duke criteria. Viridans streptococci and staphylococci accounted for 72% of cases. The prevalences of clinical features were similar to those seen in NVE: fever (temperature >/=38 degrees C, 74%) and malaise (70%), although dyspnea was more frequent (36%). There was a high incidence of serious complications (72% heart failure; 30% periannular abscesses). Surgery was required during the initial admission in 82% of cases. Overall mortality was 14%, and surgical mortality was 9%. Few patients knew they had a "heart condition," and a bicuspid aortic valve was detected in only 35% of echocardiograms performed before surgery.     

Q fever endocarditis: a case report and review of the literature

The case of a 31-year-old man from Alberta diagnosed with Q fever endocarditis is presented. To the authors' knowledge, this is the first case of Q fever endocarditis diagnosed in the province of Alberta. The patient had undergone open valvulotomy for congenital aortic stenosis as an infant. He presented with congestive heart failure secondary to severe aortic regurgitation and underwent mechanical aortic valve replacement. Early failure of the mechanical prosthesis and numerous laboratory abnormalities prompted an investigation for endocarditis, which was initially negative. Markedly positive serology eventually established the diagnosis of chronic Q fever. The patient subsequently underwent a second aortic valve replacement following initiation of appropriate antimicrobials directed against Coxiella burnetii. The present report reviews the clinical presentation and diagnosis of Q fever endocarditis. It highlights the insidious and nonspecific nature of the presenting symptoms, and emphasizes the use of serology for diagnosis. Increased awareness and earlier diagnosis can significantly decrease the morbidity and mortality associated with this disease.     

Periannular complications in infective endocarditis involving native aortic valves

The extension of infection in native valve infective endocarditis (IE) from valvular structures to the periannular tissue is incompletely understood. It is unknown, for example, whether the prognosis of patients with aortocavitary fistulae is worse than that of those with nonruptured abscesses. The aims of this study were to determine the distinct clinical characteristics of patients with aortocavitary fistulae and nonruptured abscesses in native valve IE and to evaluate the impact of fistulization on the outcomes of patients with native aortic valve IE complicated with periannular lesions. In a retrospective multicenter study of 2,055 native valve IE episodes, 201 patients (9.8%) with periannular complications in aortic valve IE were identified (46 with aortocavitary fistulization and 155 with nonruptured abscesses). Rates of heart failure (p = 0.07), ventricular septal defect (p <0.001), and third-degree atrioventricular block (p = 0.07) were higher in patients with fistulization. Surgical treatment was undertaken in 172 patients (86%), and in-hospital mortality in the overall population was 29%. Multivariate analysis identified age >60 years (odds ratio [OR] 2.6, 95% confidence interval [CI] 1.3 to 5.2), renal failure (OR 3.0, 95% CI 1.5 to 6.0), and moderate or severe heart failure (OR 2.5, 95% CI 1.2 to 5.2) as independent risk factors for death. There was a trend toward increased in-hospital mortality in patients with aortocavitary fistulae (OR 1.5, 95% CI 0.7 to 3.0). The actuarial 5-year survival rate in surgical survivors was 80% in patients with fistulae and 92% in patients with nonruptured abscesses (log-rank p = 0.6). In conclusion, aortocavitary fistulous tract formation in the setting of native valve IE is associated with higher rates of heart failure, ventricular septal defect, and atrioventricular block than nonruptured abscess. Despite these higher rates of complications, fistulous tract formation in the current era of IE is not an independent risk factor for mortality.     

Q fever bioprosthetic aortic valve endocarditis (PVE) successfully treated with doxycycline monotherapy

Q fever is a zoonotic infection caused by Coxiella burnetii. The most common clinical manifestation of acute Q fever infection is as an atypical community-acquired pneumonia. The pulmonary findings are accompanied by extrapulmonary findings, most typically an increase in serum transaminases and splenomegaly. Because C. burnetii is difficult to culture, the diagnosis of Q fever is usually made serologically. The diagnosis of acute Q fever atypical community-acquired pneumonia is made by demonstrating a fourfold or greater increase in titer between acute and convalescent specimens or by demonstrating elevated immunoglobulin (IgM) (phase II) titers. Chronic Q fever is manifested as granulomatous hepatitis or more commonly as culture-negative endocarditis (CNE). Chronic Q fever (CNE) is a difficult diagnosis because of difficulty in culturing the organism from the blood and the vegetations with Q fever CNE are small or absent. The diagnosis of chronic Q fever CNE is based on serology. Such patients commonly have highly elevated IgM and IgG titers (phase I/II) titers. Chronic Q fever CNE may involve native or prosthetic heart valves. Q fever prosthetic valve endocarditis is rare compared with native valve Q fever endocarditis. Q fever prosthetic valve endocarditis usually requires valve replacement for cure. We present a case of chronic Q fever bioprosthetic aortic valve endocarditis that was successfully treated with doxycycline monotherapy that did not require aortic valve replacement.     

Cardiac valves in patients with Q fever endocarditis: microbiological,molecular, and histologic studies

The pathologic features of Q fever endocarditis, which is caused by Coxiella burnetii, were histologically evaluated in cardiac valves from 28 patients. We used quantitative image analysis to compare valvular fibrosis, calcifications, vegetations, inflammation, and vascularization due to Q fever endocarditis with that due to non-Q fever endocarditis and valvular degeneration. We also studied the presence of C. burnetii in valves by immunohistochemical analysis, culture, and polymerase chain reaction (PCR). Histologically, Q fever endocarditis was characterized by significant fibrosis and calcifications, slight inflammation and vascularization, and small or absent vegetations. Despite antibiotic treatment, non-statistically significant variations at the histologic level were observed. These pathologic features could be confused with noninfectious valvular degenerative damage. We found that the detection of C. burnetii in cardiac valves by immunohistochemical analysis, culture, and PCR decreased significantly only after 1 year of antibiotic treatment, which emphasizes the long persistence of this organism in valve tissues. Pathologic and immunohistochemical analyses may contribute to the diagnosis of Q fever endocarditis.     

Periannular complications in infective endocarditis involving prosthetic aortic valves

The periannular extension of infection in prosthetic valve endocarditis (PVE) is a serious complication of infective endocarditis associated with high mortality. Periannular lesions in PVE occasionally rupture into adjacent cardiac chambers, leading to aortocavitary fistulae and intracardiac shunting. It is unknown whether the prognosis of patients with aortocavitary fistulae is worse than that of those with nonruptured abscesses. The aims of this study were to determine the distinctive clinical characteristics of patients with PVE and either aortocavitary fistulization or nonruptured abscesses. In a retrospective multicenter study of >872 PVE episodes, 150 patients (17%) with periannular complications in PVE in the aortic position were identified (29 with aortocavitary fistulization and 121 with nonruptured abscesses). Early-onset PVE was present in 73 patients (49%). Rates of heart failure (p = 0.09), ventricular septal defect (p <0.01), and third-degree atrioventricular block (p = 0.07) were higher in patients with fistulization. Surgical treatment was undertaken in 128 patients (83%). In-hospital mortality in the overall population was 39%. Multivariate analysis identified heart failure (odds ratio [OR] 3.3, 95% confidence interval [CI] 1.6 to 6.8), renal failure (OR 2.5, 95% CI 1.2 to 5.2), and co-morbidity (OR 2.4, 95% CI 1.1 to 5.1) as independent risk factors for death. Fistulous tract formation was not associated with increased in-hospital mortality (OR 1.6, 95% CI 0.7 to 3.7). The actuarial 5-year survival rate in surgical survivors was 100% in patients with fistulae and 78% in patients with nonruptured abscesses (log-rank p = 0.14). In conclusion, aortocavitary fistulous tract formation in PVE complicated with periannular complications is associated with higher rates of heart failure, ventricular septal defect, and atrioventricular block than nonruptured abscesses. Despite the frequent complications, fistulous tract formation in the current era of infective endocarditis is not an independent risk factor for mortality.