Echocardiography in infective endocarditis: reassessment of prognostic implications of vegetation size determined by the transthoracic and the transesophageal approach

In 105 patients with active infective endocarditis, disease-associated complications defined as severe heart failure (New York Heart Association class IV), embolic events and in-hospital death were correlated to the vegetation size determined by both transthoracic and transesophageal echocardiography. A detailed comparison between anatomic and echocardiographic findings, performed in a subgroup of 80 patients undergoing surgery or necropsy, revealed that true valvular vegetations can be reliably identified by echocardiography in the vast majority of patients; the detection rate was significantly higher for the transesophageal (90%) than for the transthoracic (58%) approach, particularly when infected prosthetic valves were evaluated. However, an accurate echocardiographic differentiation between true vegetations and other endocarditis-induced valve destruction (ruptured leaflets or chordae) is impossible. The correlation of vegetation size with endocarditis-associated complications showed that patients with a vegetation diameter greater than 10 mm had a significantly higher incidence of embolic events than did those with a vegetation diameter less than or equal to 10 mm (22 of 47 versus 11 of 58; p less than 0.01). Particularly for patients with mitral valve endocarditis, a vegetation diameter greater than 10 mm was highly sensitive in identifying patients at risk for embolic events. Vegetation size, however, was not significantly different in patients with and without severe heart failure or in patients surviving or dying during acute endocarditis. In addition, no significant correlation was found between vegetation size and location of endocarditis or type of infective organism.(ABSTRACT TRUNCATED AT 250 WORDS)     

Diagnostic value of transesophageal compared with transthoracic echocardiography in infective endocarditis

To compare the diagnostic value of transesophageal and transthoracic echocardiography in infective endocarditis, paired transesophageal and transthoracic echocardiograms were obtained prospectively for 66 episodes of suspected endocarditis in 62 patients. Echocardiographic results were compared with the presence or absence of endocarditis determined by pathologic or nonechocardiographic data from the subsequent clinical course. All echocardiograms were interpreted by an observer told only that the studies were from patients in whom the diagnosis of endocarditis was suspected. The diagnosis of endocarditis was eventually made in 16 of the 66 episodes of suspected endocarditis (14 by pathologic and 2 by clinical criteria). In 7 of 16 transthoracic and 15 of 16 transesophageal echocardiograms, endocarditis was diagnosed at a probability level of "almost certain," giving a sensitivity of 44% and 94%, respectively (p less than 0.01). For the remaining episodes, 49 of 50 transthoracic and all transesophageal studies yielded normal results, giving a specificity of 98% and 100%, respectively. This study suggests that transesophageal echocardiography is highly sensitive and specific for the diagnosis of infective endocarditis and significantly more sensitive than transthoracic echocardiography. Although echocardiography cannot rule out endocarditis, the high diagnostic sensitivity of transesophageal echocardiography results in a low probability of the disease when the study yields negative results in a patient with an intermediate likelihood of the disease.     

Has Transesophageal Echocardiography Changed the Approach to Patients with Suspected or Known Infective Endocarditis?

Infective endocarditis is still a great clinical challenge. Its diagnosis is difficult to establish, and mortality has remained around 30%. Early diagnosis and optimal treatment are crucial fo prognosis improvement. Echocardiography plays an indispensable role in the management of this disease, especially with the recently introduced approach, transesophageal echocardiography (TEE). TEE can overcome the limitations of transthoracic echocardiography (TTE) and is superior to TTE in almost every way in providing earlier and more information for the diagnosis and treatment of infective endocarditis. TEE detects valve vegetations with much higher sensitivity and specificity than TTE. It can demonstrate smaller vegetations in the early stage of the disease and vegetations on atypical locations (e.g., mitral valve annulus), and provides detailed characterization of vegetations (e.g., location, size, mobility, and changes during treatment). Such information is of great prognostic value and may help in selecting proper treatment. TEE is more sensitive for detecting complications, such as mitral valve perforation, abscess, and subaortic complications, which respond poorly to medicine and for which timely surgery may be the best treatment. For those with prosthetic valve endocarditis, TEE is especially useful because TTE is greatly limited by the acoustic shadow of prostheses. Both positive and negative results of TEE examination are valuable for confirming or excluding infective endocarditis. TEE also plays a unique role in intraoperative monitoring and can assess surgical results before the chest is closed. TEE has become an invaluable tool for the diagnosis and management of patients with suspected or known infective endocarditis.     

Role of echocardiography in the diagnosis and management of infective endocarditis

Infective endocarditis is a life-threatening disease with significant morbidity and mortality. Accurate and early diagnosis for initiation of effective treatment is essential in improving patient outcome. Echocardiography is currently the primary modality for the detection of vegetations and cardiac complications that result from endocarditis. Technological advances in echocardiography, particularly the development of transesophageal echocardiography (TEE), have revolutionized the diagnosis and management of infective endocarditis. With the enhanced resolution provided by TEE, vegetations and paravalvular complications can be reliably detected. Transthoracic and transesophageal echocardiography provides complementary information for patient management and follow-up, and is best used in conjunction with clinical data. By means of its high sensitivity and negative predictive value, TEE is essential in the evaluation of prosthetic valve endocarditis and the paravalvular complications of IE. All patients with suspected infective endocarditis should undergo transthoracic echocardiography, and most of these patients should also undergo TEE evaluation. The role of new technology such as harmonic and three-dimensional imaging is yet to be determined.     

The Potential Impact of Contemporary Transthoracic Echocardiography on the Management of Patients with Native Valve Endocarditis: A Comparison with Transesophageal Echocardiography

Background: Between 1987 and 1994, several studies demostrated transthoracic echocardiography (TTE) to be less sensitive than transesophageal echocardiography (TEE) in detecting native valve endocarditis. Recent technologic advances, especially the introduction of harmonic imaging and digital processing and storage, have improved TTE image quality. The aim of this study was to determine the diagnostic accuracy of contemporary TTE. Methods: Between 2003 and 2007, 75 patients underwent both TTE and TEE for clinically suspected infective endocarditis. The diagnostic accuracy of TTE was assessed using transesophageal echocardiography as the gold standard for diagnosis of endocarditis. Results: Of the 75 patients in this study, 33 were found to be positive by TEE. The sensitivity for detection of infective endocarditis by TTE was 81.8%. It provided good image quality in 81.5% of cases; in these patients sensitivity was even greater (89.3%). Conclusion: Contemporary TTE has improved the diagnostic accuracy of infective endocarditis by ameliorating image quality; it provides an accurate assessment of endocarditis and may reduce the need for TEE.     

Infective endocarditis, 1983-1988: echocardiographic findings and factors influencing morbidity and mortality

The echocardiograms and clinical records of 70 patients with infective endocarditis seen between 1983 and 1988 were examined to evaluate the role of two-dimensional and Doppler echocardiography in the diagnosis of infective endocarditis and identify risk factors for morbidity and mortality. A blinded observer reviewed the echocardiograms for the presence and size of vegetations and the severity of the valvular regurgitation. Vegetations were identified in 54 (78%) of 69 technically satisfactory echocardiograms. In 38 patients whose heart was examined at surgery or autopsy, all vegetations diagnosed by echocardiography were confirmed, but six additional vegetations were found. Abnormal (greater than or equal to 2+) valvular regurgitation was present in 88% of patients. No patient with less than or equal to 1+ regurgitation (n = 8) died or required valve surgery for heart failure, but three of the eight patients did undergo surgery for mycotic aneurysm, recurrent embolism or paravalvular abscess. In patients without embolism before echocardiography, there was a trend toward a greater incidence of subsequent embolism in those with vegetations greater than 10 mm in size (26% [8 of 31] compared with 11% [2 of 18] with vegetations less than or equal to 10 mm) (p = 0.19). By multivariate analysis, risk factors for in-hospital death (n = 7) were an infected prosthetic valve (p less than 0.007), systemic embolism (p less than 0.02) and infection with Staphylococcus aureus (p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Superiority of transesophageal echocardiography in detecting cardiac source of embolism in patients with cerebral ischemia of uncertain etiology

The diagnostic yield of transesophageal and transthoracic echocardiography for identifying a cardiac source of embolism was compared in 79 patients presenting with unexplained stroke or transient ischemic attack. There were 35 men and 44 women with a mean age of 59 years (range 17 to 84); 52% had clinical cardiac disease. Both transthoracic and transesophageal echocardiograms were performed using Doppler color flow and contrast imaging. Transesophageal echocardiography identified a potential cardiac source of embolism in 57% of the overall study group compared with only 15% by transthoracic echocardiography (p less than 0.0005). Compared with transthoracic echocardiography, transesophageal echocardiography more frequently identified atrial septal aneurysm associated with a patent foramen ovale (9 versus 1 of 79 patients, p less than 0.005), left atrial thrombus or tumor (6 versus 0 of 79 patients, p less than 0.05) and left atrial spontaneous contrast (13 versus 0 of 79 patients, p less than 0.0005). All cases of left atrial thrombus or spontaneous contrast were identified in patients with clinically identified cardiac disease. In the 38 patients with no cardiac disease, transesophageal echocardiography identified isolated atrial septal aneurysm and atrial septal aneurysm with a patent foramen ovale more frequently than transthoracic echocardiography (8 versus 2 of 38 patients, p less than 0.05). The two techniques had a similar rate of identifying apical thrombus and mitral valve prolapse. Overall, transesophageal echocardiography identified abnormalities in 39% of patients with no cardiac disease versus 19% for transthoracic echocardiography (p less than 0.005). Thus, transesophageal echocardiography identifies potential cardiac sources of embolism in the majority of patients presenting with unexplained stroke.(ABSTRACT TRUNCATED AT 250 WORDS)     

Echocardiography predicts embolic events in infective endocarditis

OBJECTIVES: The aim of our study was to assess the value of transesophageal echocardiography (TEE) in predicting embolic events (EEs) in a large group of patients with definite endocarditis according to the Duke criteria, including silent embolism. BACKGROUND: The value of echocardiography in predicting embolism in patients with endocarditis remains controversial. Some studies reported an increased risk of embolism in patients with large and mobile vegetations, whereas other studies failed to demonstrate such a relationship. METHODS: Multiplane transesophageal echocardiograms of 178 consecutive patients with definite infective endocarditis (IE) were analyzed. The incidence of embolism was compared with the echocardiographic characteristics (localization, size and mobility) of the vegetations. To detect silent embolism, cerebral and thoraco-abdominal scans were performed in 95% of patients. RESULTS: Among 178 patients, 66 (37%) had one or more EEs. There was no difference between patients with and without embolism in terms of age, gender and left valve involved. On univariate analysis, Staphylococcus infection, right-side valve endocarditis and vegetation length and mobility were significantly related to EEs. A significant higher incidence of embolism was present in patients with vegetation length >10 mm (60%, p < 0.001) and in patients with mobile vegetations (62%, p < 0.001). Embolism was particularly frequent among 30 patients with both severely mobile and large vegetations (> 15 mm) (83%, p < 0.001). On multivariate analysis, the only predictors of embolism were vegetation length (p = 0.03) and mobility (p = 0.01). CONCLUSIONS: Our study shows that the presence of vegetations on TEE is predictive of embolism and that the morphologic characteristics of vegetations are helpful in predicting EEs in both mitral and aortic valve IE. It also suggests that early operation may be recommended in patients with vegetations > 15 mm and high mobility, irrespective of the degree of valve destruction, heart failure and response to antibiotic therapy.     

Comparison of transthoracic and transesophageal echocardiography in evaluation of 47 Starr-Edwards prosthetic valves.

OBJECTIVES. Our objectives were to characterize by transesophageal echocardiography the normal appearance of the Starr-Edwards prosthetic heart valve and to compare the utility of transesophageal and transthoracic echocardiography in detection of valve abnormality. BACKGROUND. The Starr-Edwards prosthetic heart valve, the first mechanical valve to be used, has demonstrated excellent durability. METHODS. Fifty transthoracic and transesophageal echocardiographic studies on 37 patients with 47 Starr-Edwards prosthetic valves were analyzed retrospectively. Six cases of surgically confirmed infective endocarditis were studied. RESULTS. Vegetation or abscess formation, or both, was identified by transesophageal echocardiography in all six cases of infective endocarditis but was found in only one of these cases by transthoracic echocardiography. Thrombus was detected by transesophageal echocardiography in 9 of 11 patients with transient ischemic attacks or stroke and in 2 patients by transthoracic echocardiography with 3 confirmed at surgery. In 26 of the 30 patients with a mitral Starr-Edwards valve, the valve demonstrated a trivial or mild "closing volume" early systolic or holosystolic leak on transesophageal echocardiography alone. Transthoracic evaluation identified significant mitral regurgitation in six of the eight patients who had this finding on transesophageal echocardiography. Serial studies were performed to assess response to treatment or need for surgical intervention in eight patients. Seventeen valves have been implanted for 12 years; six of these had significant leakage without apparent cause, a finding not observed more recently implanted valves. CONCLUSIONS. These observations demonstrated the unique utility of transesophageal echocardiography in patients with Starr-Edwards prosthetic valve dysfunction, endocarditis or thrombus formation, and of the clear superiority of transesophageal echocardiography over transthoracic echocardiography in these situations.     

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.     

The value of the Von Reyn and the Duke diagnostic criteria for infective endocarditis in internal medicine practice. A study of 38 cases

BACKGROUND: The aim of our study was to compare the value of the Von Reyn and the Duke diagnostic criteria for infective endocarditis (IE) in internal medicine practice. METHODS: We determined the sensitivity and negative predictive value of these two sets of diagnostic criteria in 38 patients with established infective endocarditis who were followed in two departments of general internal medicine. The patients essentially had subacute endocarditis of the aortic valve (79%) with several systemic manifestations (100%). Microbial documentation included mainly gram-positive cocci (60%). RESULTS: With transthoracic echocardiography (TTE), the sensitivities of the Duke and the Von Reyn criteria were 65% and 35%, respectively, while with transesophageal echocardiography (TEE), these sensitivities were 75% and 35%, respectively. With TTE and TEE, the negative predictive values were 100% for the Duke diagnostic criteria versus only 71% for the Von Reyn criteria. CONCLUSIONS: This study confirms that the Duke diagnostic criteria are useful in practice for the management of patients with infective endocarditis followed in internal medicine.     

Prognostic value of echocardiographic finding of valvular vegetations in patients with infectious endocarditis

42 consecutive patients with infective endocarditis on native valves, according to Pelletier and Petersdorf's criteria of definite (13 pts), probable (12 pts.) and possible (17 pts) endocarditis, were identified and prospectively followed-up with M-mode and two-dimensional echocardiography, since 1980. We compared: 1) these three groups; 2) survivors not referred for surgery versus surgical patients plus nonsurvivors; 3) patients who suffered embolic events versus those who did not; 4) patients with severe-moderate heart failure versus those with no failure or mild failure; 5) patients with aortic valve echocardiographic vegetations versus those with mitral valve vegetations. Furthermore 11 of these patients who did not undergo surgery (9 with mitral and 2 with mitro-aortic vegetations on echo) were serially followed-up with echocardiography for 6-42 months (average: 32 months). The presence of ultrasound detectable vegetations itself and their size, without considering their site, did not identify a major risk of embolization, heart failure, death or need of surgery. The site of vegetations was the only significant feature in our series. It identified a high-risk group and a relatively low-risk group. Aortic valve involvement, with echocardiographic vegetations, was related to severe or moderate heart failure (P less than 0.01), death or need of surgery (P less than 0.05). Mitral valve involvement carried on a relatively low risk. The 9 patients with mitral valve vegetations only, not referred for surgery and followed-up, did well on medical treatment and returned to work. They did not have relapses or embolization. On serial echocardiographic examinations, mitral vegetations become smaller in the long run. Two years after the acute episode, usually echocardiography did not allow identification of vegetations.     

The limitations of echocardiography in the overall diagnosis of the morphological lesions associated with infective endocarditis: comparison of echocardiographic and surgical findings

Echocardiography is commonly accepted as the method of choice for the non-invasive diagnosis of vegetations and other lesions associated with infective endocarditis. To assess the accuracy of echocardiography in the overall diagnosis of the morphological cardiac lesions we retrospectively analyzed and compared the preoperative echocardiographic data with the surgical findings of 120 consecutive cases operated for infective endocarditis. Transthoracic echocardiography (TTE) was used in 60 cases (51 with native and 9 with prosthetic valves), both TTE and transesophageal echocardiography (TEE) in 50 (26 with native and 24 with prosthetic valves) and only TEE in 10 patients who underwent emergency surgery. The echocardiographic diagnosis was correct in all the cases, but incomplete in 26 (16 with native and 10 with prosthetic valves). Most of the incomplete diagnoses occurred regarding vegetations, perforations of the valvular leaflets and perivalvular abscesses. There were no differences between aortic or mitral valves (14/66 vs 11/60; p = ns), native or prosthetic (16/79 vs 10/37; p = ns), TTE or TEE (13/60 vs 13/60; p = ns); however, TEE was performed in more complex cases and in severely ill patients. In six of the incomplete diagnoses, echocardiography preceded surgery by one week or more, and in six the mistakes were not confirmed by the reviewer. In conclusion, our study suggests that an echocardiographic diagnosis of endocarditis may be correct but sometimes incomplete. In patients without prosthetic valves who have a technically-adequate transthoracic echocardiogram, transesophageal echocardiography is not indispensable but should be chosen from time to time. However, the patients with endocarditis and no contraindication to the transesophageal procedure should undergo both transesophageal and transthoracic echocardiography before surgery in order to obtain as much and the most definite information possible. An echocardiographic study should be repeated just before any surgical procedures in patients with active endocarditis. Finally, it needs to be emphasized that the training and clinical judgement of the operator performing the study are important elements determining the results of echocardiographic study.     

The relative roles of transthoracic compared with transesophageal echocardiography in children with suspected infective endocarditis

OBJECTIVES: The study evaluated the additional benefit of transesophageal echocardiography (TEE) versus transthoracic echocardiography (TTE) in pediatric cases with suspected bacterial endocarditis. BACKGROUND: In adult patients, TTE has a lower sensitivity and specificity than TEE for the detection of vegetations or aortic root abscess formation. Few data are available about the relative benefits of TEE over TTE in the pediatric age group. METHODS: Patients were included if they had positive blood cultures for typical microorganisms and had a TTE and TEE within 14 days of each other. The patients had to meet the Duke criteria for a positive diagnosis of bacterial endocarditis. The TTE and TEE data were analyzed using the McNemar test for the significance of change. RESULTS: Twenty-one patients fulfilled the criteria, at a median age of 9.5 years. Congenital heart disease was present in 13 patients; 4 patients were previously healthy and 4 patients had other medical problems. Nine patients had surgical confirmation of bacterial endocarditis. Fifteen patients had a positive cardiac finding, with 12 vegetations, 2 vegetations plus aortic root abscess, and 1 isolated abscess. There was excellent agreement between TTE and TEE in those cases with positive cardiac findings, with a p = 0.32, kappa 0.89. Using positive TEE cardiac findings as the gold standard, the sensitivity for TTE was 86% for all 15 events and 93% for the detection of a vegetation. CONCLUSIONS: In pediatric cases, TTE has a high degree of sensitivity for the detection of supportive evidence of endocarditis, and TEE should be reserved for patients with a poor transthoracic window.     

Transthoracic versus transesophageal echocardiography for detection of Libman-Sacks endocarditis: a randomized controlled study

OBJECTIVE: Libman-Sacks endocarditis in patients with systemic lupus erythematosus (SLE) is complicated with thromboembolism, severe valve regurgitation, need for high-risk valve surgery, or death. Transesophageal echocardiography (TEE) is highly accurate for detection of valvular heart disease, but there are no prospective randomized controlled series comparing transthoracic echocardiography (TTE) to TEE for detection of Libman-Sacks endocarditis. METHODS: Eighty-one patients with SLE (73 women, 8 men) with a mean age of 39 +/- 11 years and 75 healthy volunteers (40 women, 35 men) with a mean age of 35 +/- 9 years underwent paired TTE and TEE to detect valve vegetations, thickening, or >or= moderate mitral, tricuspid, or pulmonic >or= mild aortic regurgitation. Paired TTE and TEE studies of patients and controls were randomized and interpreted by an experienced observer unaware of subjects' data. RESULTS: Libman-Sacks endocarditis: (1) was more common in patients than in controls by both TTE and TEE (p < 0.001); and (2) was more commonly detected by TEE than by TTE (p 相似文献   

Echocardiographic assessment of vegetations in patients with infective endocarditis: prognostic implications

Today, echocardiography is the most important technique next to clinical findings and blood cultures in the diagnosis of infective endocarditis. The sensitivity of echocardiography, particularly the transesophageal approach, for detection of vegetations and endocarditis related valvular destructions is high. In addition, echocardiographic findings may have some prognostic implications. The size and mobility of vegetations stratifies endocarditis patients into a high risk group for arterial embolism. In particular, mobile vegetations attached to the mitral valve with a maximal diameter > 10 mm may be prone to embolic events. Furthermore, increase in size of vegetations during antimicrobial treatment may identify patients with no, or at least a prolonged, healing process. Also, a lack of increase in the echo density of vegetations under adequate antibiotic treatment may indicate a poor healing process and may necessitate more aggressive management. The demonstration of paravalvular abscesses by echocardiography, particularly by transesophageal echocardiography, identifies a subgroup of patients who will need urgent cardiac surgery before widespread tissue destruction has occurred.     

Emboli in infective endocarditis: the prognostic value of echocardiography

OBJECTIVE: To determine whether vegetations visualized on two-dimensional echocardiography are an independent risk factor for the development of subsequent emboli in patients with infective endocarditis and to assess the timing of emboli relative to the initiation of antimicrobial therapy. DESIGN: Investigator-blinded, retrospective incidence cohort study. SETTING: Tertiary referral center. PATIENTS: Patients with left-sided native valve infective endocarditis who had two-dimensional echocardiography within 72 hours of beginning antimicrobial therapy. MEASUREMENTS AND MAIN RESULTS: The crude incidence rate of first embolic events in patients receiving antimicrobial therapy was 6.2 per 1000 patient-days (95% CI, 4.2 to 9.2). The rates in patients with and without vegetations were 7.1 and 4.9 per 1000 patient-days, respectively (incidence rate ratio, 1.4; 95% CI, 0.6 to 3.3). The relation between vegetations and risk for emboli was microorganism-dependent: Stratified incidence rate ratios were 6.9 (95% CI, 1.1 to 42.5; P less than 0.05) and 1.0 (95% CI, 0.2 to 3.9) for viridans streptococcal and Staphylococcus aureus endocarditis, respectively. The rate of first embolic events diminished over time (P less than 0.001), falling from 13 per 1000 patient-days during the first week of therapy to less than 1.2 per 1000 patient-days after completion of the second week of therapy. CONCLUSIONS: Overall, the presence of vegetations on echocardiography was not associated with a significantly higher risk for embolus in patients with left-sided native valve infective endocarditis. The relative risk for embolic events associated with echocardiographically visualized vegetations may be microorganism-dependent, with a significantly increased risk seen only in patients with viridans streptococcal infection. The rate of embolic events declines with time after initiation of antimicrobial treatment.     

Role of Echocardiography in Evaluation of Patients With Staphylococcus aureusBacteremia: Experience in 103 Patients

Objectives. The purpose of this prospective study was to examine the role of echocardiography in patients with Staphylococcus aureusbacteremia (SAB).Background. The reported incidence of infective endocarditis (IE) among patients with SAB varies widely. Distinguishing patients with uncomplicated bacteremia from those with IE is therapeutically and prognostically important, but often difficult.Methods. One hundred-three consecutive patients undergoing both transthoracic (TTE) echocardiography and transesophageal (TEE) echocardiography were prospectively evaluated. All patients presented with fever and ≥1 positive blood culture and were followed up for 12 weeks.Results. Although predisposing heart disease was present in 42 patients (41%), clinical evidence of infective endocarditis (IE) was rare (7%). TTE revealed anatomic abnormalities in 33 patients, but vegetations in only 7 (7%), and was considered indeterminate in 19 (18%). TEE identified vegetations in 22 patients (aortic valve in 5, mitral valve in 9, tricuspid valve in 4, catheter in 2 and pacemaker in 2, abscesses in 2, valve perforation in 1 and new severe regurgitation in 1; 26 total [25%]). Using Duke criteria for the diagnosis of IE, definite IE was present in 26 patients (25%). Clinical findings and predisposing heart disease did not distinguish between patients with and without IE. The sensitivity of TTE for detecting IE was 32%, and the specificity was 100%. The addition of TEE increased the sensitivity to 100%, but resulted in one false positive result (specificity 99%). TEE detected evidence of IE in 19% of patients with a negative TTE and 21% of patients with an indeterminate TTE. At follow-up, cure of staphylococcal infection occurred in a similar percentage of patients with and without IE (77% and 75%, respectively). However, death due to sepsis was significantly more likely among patients with IE (4 of 26 [15%]) than among those without IE (2 of 77 [3%]) (p = 0.03).Conclusions. Our results suggest that IE is common among patients admitted to the hospital with SAB and is associated with an increased risk of death due to sepsis. TEE is essential to establish the diagnosis and to detect associated complications. Therefore, the test should be considered part of the early evaluation of patients with SAB.     

Surgical management of infective endocarditis

BACKGROUND AND AIM OF THE STUDY: Although retrospective reviews evaluating the surgical management of infective endocarditis (IE) have been conducted in Europe and in the USA, few data exist regarding management of the condition in Canada. The study aim was to evaluate the surgical management of individuals with culture-positive active IE at a Canadian tertiary care university hospital. METHODS: A retrospective analysis was performed of 74 patients (53 males, 21 females; mean age 56 +/- 14 years) with a preoperative diagnosis of acute IE between 1995 and 2003 at the Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia. Preoperative clinical variables evaluated included the Duke criteria for endocarditis, correlation between preoperative echocardiographic imaging and intraoperative findings, and postoperative morbidity and mortality. RESULTS: Native valve endocarditis (NVE) was present in 60 patients, and prosthetic valve endocarditis (PVE) in 14. All patients met the Duke criteria for endocarditis. Correlation between preoperative transesophageal echocardiography (TEE) and surgical findings (vegetations 63%, abscesses 96%, leaflet perforation 100%) was superior when compared with preoperative transthoracic echocardiography (vegetations 43%, abscesses 75%, leaflet perforation 89%). There were low rates of postoperative morbidity (reoperation 8%, stroke 5%). Overall in-hospital mortality was 14% (seven NVE, 12%; three PVE, 21%). CONCLUSION: Herein is presented the largest and most current case series of patients treated surgically for active IE. The results demonstrate excellent agreement between preoperative TEE and intraoperative surgical findings in the current era of surgical management of this condition.     

Value of transesophageal echocardiography as an adjunct to transthoracic echocardiography in evaluation of native and prosthetic valve endocarditis

To determine if transesophageal echocardiography provides better visualization of valvular vegetations than transthoracic echocardiography, we used both methods to evaluate 24 consecutive patients (mean age, 54 years; 15 female patients and nine male patients) referred for symptoms suggestive of infectious endocarditis. Ten of the 24 patients had one or more valvular prostheses. Echocardiograms were classified as positive or negative based on visualization of valvular vegetations or abscesses. Of ten patients with a final diagnosis of infectious endocarditis on extended follow-up, transthoracic echocardiography was positive in five patients. Transesophageal echocardiography not only yielded abnormal findings in all ten of these patients, but also revealed additional information in four of the five patients with abnormal transthoracic echocardiographic examinations. Among the 14 patients who, on subsequent follow-up, were found not to have infectious endocarditis, transthoracic echocardiography was normal in 13 and falsely abnormal in one. Transesophageal echocardiography revealed no evidence of infectious endocarditis in any of these patients. The ten patients who were determined to have infectious endocarditis all had positive blood cultures and no alternative cause for their clinical presentation; in seven patients in this group who underwent operative or postmortem evaluation, infectious endocarditis was confirmed. All patients without infectious endocarditis were demonstrated to have other causes for their clinical presentation. We conclude that transesophageal echocardiography is a highly valuable test in the work-up of patients with suspected infectious endocarditis, especially those patients with inconclusive or normal transthoracic echocardiograms. In addition, transesophageal echocardiography may be of benefit to patients with previously documented infectious endocarditis and a complicated clinical course in whom additional cardiac lesions are suspected but not demonstrated by transthoracic echocardiography.