Role of transoesophageal echocardiography in the diagnosis and management of aortic root abscess

Atrioventricular conduction disorders in aortic valve infective endocarditis

BACKGROUND

Aortic valve infective endocarditis may be complicated by high-degree atrioventricular block in up to 10-20% of cases.

AIM

To assess high-degree atrioventricular block occurrence, contributing factors, prognosis and evolution in patients referred for aortic infective endocarditis.

METHODS

Two hundred and five patients referred for aortic valve infective endocarditis between January 2018 and March 2021 were included in this study. A comprehensive assessment of clinical, electrocardiographic, biological, microbiological and imaging data was conducted, with a follow-up carried out over 1 year.

RESULTS

High-degree atrioventricular block occurred in 22 (11%) patients. In univariate analysis, high-degree atrioventricular block was associated with first-degree heart block at admission (odds ratio 3.1; P=0.015), periannular complication on echocardiography (odds ratio 6.9; P<0.001) and severe biological inflammatory syndrome, notably C-reactive protein (127 vs 90mg/L; P=0.011). In-hospital mortality (12.7%) was higher in patients with high-degree atrioventricular block (odds ratio 4.0; P=0.011) in univariate analysis. Of the 16 patients implanted with a permanent pacemaker for high-degree atrioventricular block and interrogated, only four (25%) were dependent on the pacing function at 1-year follow-up.

CONCLUSIONS

High-degree atrioventricular block is associated with high inflammation markers and periannular complications, especially if first-degree heart block is identified at admission. High-degree atrioventricular block is a marker of infectious severity, and tends to raise the in-hospital mortality rate. Systematic assessment of patients admitted for infective endocarditis suspicion, considering these contributing factors, could indicate intensive care unit monitoring or even temporary pacemaker implantation in those at highest risk.

Homograft Versus Valves and Valved Conduits for Extensive Aortic Valve Endocarditis with Aortic Root Involvement/Destruction: A Systematic Review and Meta-Analysis

Aortic valve infective endocarditis is a life-threatening condition. Patients frequently present profoundly unwell and extensive surgery may be required to correct the underlying anatomical deficits and control sepsis. Periannular involvement occurs in more than 10% of patients with aortic valve endocarditis. Complex aortic valve endocarditis has a mortality rate of 10 to 40%. Longstanding surgical dogma suggests homografts represent the optimal replacement option in complex aortic valve endocarditis; however, there is a paucity of evidence and lack of consensus on the optimal replacement choice. A systematic review and meta-analysis was performed utilizing EMBASE, PubMed, and the Cochrane databases to review articles describing homografts versus aortic valve replacement and/or valved conduit graft implantation for complex aortic valve endocarditis. The outcomes of interest were mortality, reinfection, and reoperation. Eleven studies were included in this meta-analysis, contributing 810 episodes of complex aortic valve endocarditis. All included reports were cohort studies. There was no statistically significant difference in overall mortality (risk ratio [RR] 0.99; 95% confidence interval [CI], 0.61–1.59; p  = 0.95), reinfection (RR 0.89; 95% CI, 0.45–1.78; p  = 0.74), or reoperation (RR 0.91; 95% CI, 0.38–2.14; p  = 0.87) between the homograft and valve replacement/valved conduit graft groups. Overall, there was no difference in mortality, reinfection, or reoperation rates between homografts and other valve or valved conduits in management of complex aortic endocarditis. However, there is a paucity of high-quality evidence in the area, and comparison of valve types warrants further investigation.

Perivalvular Extension of Infective Endocarditis after Transcatheter Aortic Valve Replacement

BACKGROUND

Infective endocarditis (IE) following transcatheter aortic valve replacement (TAVR) has been associated with a dismal prognosis. However, scarce data exist on IE perivalvular extension (PEE) in such patients.

METHODS

This multicenter study included a total of 579 patients who had the diagnosis of definite IE at a median of 171 (53-421) days following TAVR. PEE was defined as the presence of an intracardiac abscess, pseudoaneurysm or fistula confirmed by transthoracic/transophageal echocardiography, computed tomography or peri-operative findings.

RESULTS

A total of 105 patients (18.1%) were diagnosed with PEE (perivalvular abscess, pseudoaneurysm, fistula, or a combination in 87, 7, 7, and 4 patients, respectively). A history of chronic kidney disease (ORadj: 2.08; 95% CI: [1.27-3.41], p=0.003) and IE secondary to coagulase-negative staphylococci (ORadj: 2.71; 95% CI: [1.57-4.69], p<0.001) was associated with an increased risk of PEE. Surgery was performed at index IE episode in 34 patients (32.4%) with PEE (vs. 15.2% in patients without PEE, p<0.001). In-hospital and 2-year mortality rates among PEE-IE patients were 36.5% and 69.4%, respectively. Factors independently associated with an increased mortality risk were the occurrence of other complications (stroke post-TAVR, acute renal failure, septic shock) and the lack of surgery at index IE hospitalization (padj<0.05 for all).

CONCLUSION

PEE occurred in about one fifth of IE post-TAVR patients, with the presence of coagulase-negative staphylococci and chronic kidney disease determining an increased risk. Patients with PEE-IE exhibited very high early and late mortality rates, and surgery during IE hospitalization seemed to be associated with better outcomes.

PR interval prolongation is significantly associated with aortic root abscess: An age- and gender-matched study

BACKGROUND

Electrocardiographic abnormalities, such as PR interval prolongation, have been anecdotally reported in patients with aortic root abscess (ARA). An electrocardiographic marker may be useful in identifying those patients with aortic valve endocarditis who may progress to ARA. The objective of this study is to evaluate the change in the PR interval in patients with surgically confirmed ARA and compare it to age- and gender-matched controls with echocardiographically or surgically confirmed aortic valve endocarditis but without aortic root abscess and those hospitalized with diagnoses other than endocarditis.

METHODS

Patients were eligible for enrollment if they were 18 years or older and were hospitalized for either ARA, aortic valve endocarditis, or for unrelated reasons and had at least one 12-lead electrocardiogram (ECG) prior to or on the day of hospitalization and at least one ECG after hospitalization but prior to any cardiac surgical procedure. Delta PR interval, defined as the difference between the pre- and post-admission PR interval, was the primary outcome of interest. The patients in the ARA group were age- and gender-matched to patients with aortic valve endocarditis and to those without endocarditis. Comparisons of demographic variables and study outcomes were performed.

RESULTS

Eighteen patients with surgically confirmed ARA were enrolled. These patients were age- and gender-matched to 19 patients with aortic valve endocarditis and 18 patients with no past history or evidence of endocarditis during hospitalization. No difference was noted in the baseline PR interval between the groups. However, the PR interval following admission in the aortic root abscess group (201 ± 66 ms) was significantly longer than the PR interval in both the aortic valve endocarditis (162 ± 27 ms) (24%, p = .009) and no endocarditis (143 ± 24 ms) (40%, p < .001) groups. The primary outcome measure, delta PR interval, was significantly longer in the ARA group (35 ± 51 ms) than no endocarditis (-5 ± 17 ms) (p = .001) and aortic valve endocarditis groups (0.2 ± 18) (p = .003).

CONCLUSIONS

The findings of our study support the notion that the PR interval is more likely to be prolonged in patients with ARA. Since ARA is associated with a high morbidity and mortality, PR interval prolongation in a patient with aortic valve endocarditis should prompt a thorough evaluation for aortic root involvement.

A narrative review of echocardiography in infective endocarditis of the right heart

Infective endocarditis (IE) is characterized by bacterial or fungal masses that form in the cardiac chambers and valves, and in severe cases invade the endocardium or intra-cardiac vessels. Right-sided IE accounts for 5% to 10% of cases, with a low mortality cited at 6%. A history of intravenous drug abuse (IVDU) is present in 90% of isolated right-sided IE cases, with normal intra-cardiac anatomy prior to infection in approximately 80%. Nevertheless, up to 50% of patients require early surgical intervention which is associated with significant peri-operative morbidity. Echocardiography is the gold standard for diagnosis with a sensitivity of 80% for the transthoracic modality and 95% for transesophageal studies; it provides important clinical information regarding the severity of infection and development of secondary complications. This includes identification of active infective vegetations, healed IE, prosthetic valve IE, and abscess formation and rupture. Prompt clinical, microbiologic, and imaging assessment of patients with suspected left or right-sided IE is of paramount importance and is reflected in the modified Duke criteria, the well-validated algorithm for accurate and timely diagnosis of IE. Data suggests the criteria sensitivity may be decreased in right-sided IE only, and thus, care must be taken to perform skilled and detailed echocardiographic assessments of the right heart in suspected cases. Herein we provide a review of IE of the right heart, with a focus on pathophysiology and its echocardiographic presentation and characteristics.

Prevalence and predictors of aortic root abscess among patients with left-sided infective endocarditis: a cross-sectional comparative study

BACKGROUND

Aortic root abscess (ARA) is a major complication of infective endocarditis that is associated with increased morbidity and mortality. Limited data are present about patient characteristics and outcomes in this lethal disease. We aimed to study the clinical and echocardiographic characteristics of patients with ARA compared to patients with left-sided infective endocarditis without ARA. We included patients with a definite diagnosis of left-sided infective endocarditis according to modified Duke's criteria. The patients were classified into two groups according to the presence of ARA (ARA and NO-ARA groups). All the patients were studied regarding their demographic data, clinical characteristics, laboratory and imaging data, and complications.

RESULTS

We included 285 patients with left-sided infective endocarditis. The incidence of ARA was 21.4% (61 patients). Underlying heart disease, mechanical prosthesis, bicuspid aortic valve, and prior IE were significantly higher in ARA. The level of CRP was higher in ARA (p = 0.03). ARA group showed more aortic valve vegetations (73.8% vs. 37.1%, p < 0.001), more aortic paravalvular leakage (26.7% vs. 4.5%, p < 0.001), and less mitral valve vegetations (21.3% vs. 68.8%, p < 0.001). Logistic regression analysis showed that the odds of ARA increased in the following conditions: aortic paravalvular leak (OR 3.9, 95% CI 1.2-13, p = 0.03), mechanical prosthesis (OR 3.6, 95% CI 1.5-8.7, p = 0.005), aortic valve vegetations (OR 3.0, 95% CI 1.2-8.0, p = 0.02), and undetected organism (OR 2.3, 95% CI 1.1-4.6, p = 0.02), while the odds of ARA decreased with mitral valve vegetations (OR 0.2, 95% CI 0.08-0.5, p = 0.001). We did not find a difference between both groups regarding the incidence of major complications, including in-hospital mortality.

CONCLUSION

In our study, ARA occurred in one fifth of patients with left-sided IE. Patients with mechanical prosthesis, aortic paravalvular leakage, aortic vegetations, and undetected organisms had higher odds of ARA, while patients with mitral vegetations had lower odds of ARA.

Utility of CT in the diagnosis of prosthetic valve abnormalities

BACKGROUND

Patients with prosthetic heart valves (PHV) are at an increased risk of endocarditis and dysfunction. Knowledge about the etiology of dysfunction and extent of endocarditis can have distinct treatment implications. Echocardiography has limitations due to PHV-related artifacts. We hypothesized that computed tomography (CT) will have incremental value over echocardiography for evaluation of PHV abnormalities with surgical findings as the reference standard.

METHODS

Consecutive patients with PHV that had a reoperation for valve replacement, had a contrast chest CT and echocardiogram within 1 year of the reoperation, between 2010 and 2018 at a single academic center formed the study cohort. CTs and echocardiograms were assessed for potential etiologies of dysfunction (valve degeneration, pannus and thrombus); and for extent of endocarditis (vegetation, abscess, and pseudoaneurysm).

RESULTS

Seventy-three patients (65.8% male, mean age 62.1 ± 16.5 years) formed the study cohort. The indication for reoperation was PHV dysfunction in 51 and PHV endocarditis in 22. Compared to echocardiography, CT diagnosed the etiology of PHV dysfunction in 17 (33.3%) more patients (9 valve degeneration, 8 pannus). In the PHV endocarditis cohort, CT failed to detect one vegetation and one abscess, whereas echocardiography failed to detect 1 abscess. In combination, CT and echocardiography demonstrated all the vegetations and abscesses.

CONCLUSION

CT may provide superior characterization in comparison to echocardiography for the identification of the cause of prosthetic valve dysfunction, and complementary information to echocardiography for the evaluation of prosthetic valve endocarditis.

Open transcatheter aortic valve implantation on a degenerated bioprosthetic valve conduit

The degeneration of bioprosthetic aortic Conduit with hemodynamic dysfunction mostly requires a re-do surgery, which is associated with an increased perioperative risk. Considering this, an open implantation of a transcatheter aortic bioprothesis (TAVI) after resection of the degenerated valve leaflets could be of great benefit, reducing cross-clamp and cardiopulmonary bypass duration, especially in combined surgery in high-risk patients. This is a case of a high-risk female (78 years, EuroScore 59%) treated with an open TAVI as an alternative to conventional valve or aortic conduit replacement for degenerative aortic valve due to endocarditis lente, 2 years following a bio-Bentall procedure.

Early Surgery in Valvular Heart Disease

The burden of valvular heart disease (VHD) is increasing with age, and the elderly patients with moderate or severe VHD are notably common. When to operate in asymptomatic patients with VHD remains controversial. The controversy is whether early surgical intervention should be preferred, or a watchful waiting approach should be followed. The beneficial effects of early surgery should be balanced against operative mortality and long-term results. Indications of early surgery in each of the VHD will be discussed in this review on the basis of the latest American and European guidelines.

Is Transesophageal Echocardiography Needed before Hospital Discharge in Patients after Bentall Surgery?

BACKGOUND

Whether transesophageal echocardiography (TEE) should be routinely performed before hospital discharge after Bentall surgery remains unclear. The investigators took advantage of this practice at their institution to evaluate its benefit.

METHODS

All patients who had undergone the Bentall procedure at Bichat Hospital from January 2010 to March 2014 were included. For each patient, transthoracic echocardiographic and transesophageal echocardiographic data and clinical events were retrospectively collected from the various reports.

RESULTS

One hundred ninety-eight patients underwent the Bentall procedure during the study period. Postoperative TEE was performed in 117 patients (59.1%), including nine with abnormalities observed on transthoracic echocardiography (a vibrating element on the new prosthetic valve, suspicion of peritubular complications in two patients, and aortic regurgitation in six patients). In 108 patients, routine TEE was performed (i.e., without clinical indication beyond baseline postoperative imaging). Patients with and those without routine TEE were identical, except for more frequent endocarditis as an indication for surgery in patients with routine TEE. Routine TEE did not reveal any new findings that prior transthoracic echocardiography had not shown. The most frequent finding on transthoracic echocardiography or TEE was periaortic hematoma, which sometimes led to the performance of computed tomography. This imaging did not change the care of the patients in this population.

CONCLUSIONS

This study does not support the performance of TEE after Bentall surgery during the in-hospital course in the absence of a specific indication. Baseline postoperative imaging using TEE or computed tomography should preferably be recommended beyond the early postoperative period after periaortic hematoma has resolved.

[Which patients with infective endocarditis require emergency surgery?]

Half of patients with infectious endocarditis have surgery during the active phase of infective endocarditis (before the end of antibiotic therapy). The American Heart Association and the European Society of Cardiology, independently from each other, have published guidelines in September 2015. As regards surgical indications, these guidelines are similar. The surgical indication must be a common decision of a multidisciplinary team of experts in cardiology, cardiac surgery, imaging and infectious diseases. The main indications are heart failure, non-infectious process control and prevention of embolisms.

Infective Endocarditis in Adults: Diagnosis, Antimicrobial Therapy, and Management of Complications: A Scientific Statement for Healthcare Professionals From the American Heart Association

BACKGROUND

Infective endocarditis is a potentially lethal disease that has undergone major changes in both host and pathogen. The epidemiology of infective endocarditis has become more complex with today's myriad healthcare-associated factors that predispose to infection. Moreover, changes in pathogen prevalence, in particular a more common staphylococcal origin, have affected outcomes, which have not improved despite medical and surgical advances.

METHODS AND RESULTS

This statement updates the 2005 iteration, both of which were developed by the American Heart Association under the auspices of the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease of the Young. It includes an evidence-based system for diagnostic and treatment recommendations used by the American College of Cardiology and the American Heart Association for treatment recommendations.

CONCLUSIONS

Infective endocarditis is a complex disease, and patients with this disease generally require management by a team of physicians and allied health providers with a variety of areas of expertise. The recommendations provided in this document are intended to assist in the management of this uncommon but potentially deadly infection. The clinical variability and complexity in infective endocarditis, however, dictate that these recommendations be used to support and not supplant decisions in individual patient management.

Cardiac Tamponade following Mitral Valve Replacement for Active Infective Endocarditis with Ring Abscess

Periannular extension and abscess formation are rare but deadly complications of infective endocarditis (IE) with high mortality. Multimodality cardiac imaging, invasive and noninvasive, is needed to accurately define the extent of the disease. Debridement, reconstruction, and valve replacement, often performed in an emergent setting, remain the treatment of choice. Here we present a case of severe IE in a 29-year-old intravenous drug user who after undergoing debridement of the abscess, annular reconstruction, and mitral valve replacement (MVR) presented with recurrence of shortness of breath and pedal edema. Transthoracic echocardiogram (TTE) showed a 6.2 × 5.5 cm cavity, posterior to and communicating with the left ventricle through a 3 cm wide fistulous opening, in proximity of the reconstructed mitral annulus. The patient underwent a redo MVR with patch closure of the fistulous opening, with good clinical outcome. This case highlights the classic TTE findings and the necessity for close follow-up in the perioperative period in patients undergoing surgery for periannular extension of infection. A cardiac magnetic resonance imaging can be considered, preoperatively, in such cases to identify the extent of myocardial involvement and surgical planning.

Are novel non-invasive imaging techniques needed in patients with suspected prosthetic heart valve endocarditis? A systematic review and meta-analysis

Objectives

Multimodal non-invasive imaging plays a key role in establishing a diagnosis of PHV endocarditis. The objective of this study was to provide a systematic review of the literature and meta-analysis of the diagnostic accuracy of TTE, TEE, and MDCT in patients with (suspected) PHV endocarditis.

Methods

Studies published between 1985 and 2013 were identified via search and cross-reference of PubMed/Embase databases. Studies were included if (1) they reported on the non-invasive index tests TTE, TEE, or MDCT; (2) data was provided on PHV endocarditis as the condition of interest; and (3) imaging results were verified against either surgical inspection/autopsy or clinical follow-up reference standards, thereby enabling the extraction of 2-by-2 tables.

Results

Twenty articles (including 496 patients) met the inclusion criteria for PHV endocarditis. TTE, TEE, and MDCT + TEE had a pooled sensitivity/specificity for vegetations of 29/100 %; 82/95 %, and 88/94 %, respectively. The pooled sensitivity/specificity of TTE, TEE, and MDCT + TEE for periannular complications was 36/93 %, 86/98 %, and 100/94 %, respectively.

Conclusions

TEE showed good sensitivity and specificity for establishing a diagnosis of PHV endocarditis. Although MDCT data are limited, this review showed that MDCT in addition to TEE may improve sensitivity in detecting life-threatening periannular complications.

Key Points

• Multimodal imaging is an important ingredient of diagnostic workup for PHV endocarditis.

• Transthoracic and transesophageal echography may miss life-threatening periannular complications.

• MDCT can improve sensitivity for the detection of life-threatening periannular complications.

Electronic supplementary material

The online version of this article (doi:10.1007/s00330-015-3605-7) contains supplementary material, which is available to authorized users.

Pseudoaneurysm of the mitral-aortic intervalvular fibrosa. A new comprehensive review

Pseudoaneurysm of the mitral-aortic intervalvular fibrosa (P-MAIVF) is an infrequent but potentially life-threatening condition. Both transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) can detect P-MAIVF with sensitivity rates of 43 and 90 %, respectively. The typical finding of echocardiography is a pulsatile echo-free sac that expands in systole and collapses in diastole. Our review comprises 166 patients with P-MAIVF, including eight cases in our hospital and 158 cases from the literature. P-MAIVF is often associated with infection or surgical trauma. While it is likely to maintain an asymptomatic course, symptoms of shortness of breath, heart failure, valvular disease, chest pain, endocarditis, and cerebrovascular events are common clinical presentations. The recommended treatment is surgery. However, conservative therapy is an alternative approach for high-risk patients or when surgical treatment is refused. With the increasing incidence of cardiac surgery and infective endocarditis, a likely increment in the new diagnosis of pseudoaneurysm is expected.

Ruptured anterior mitral leaflet aneurysm in aortic valve infective endocarditis--evaluation by three-dimensional echocardiography

Ruptured aneurysm of the anterior mitral leaflet is a rare but a devastating complication secondary to aortic valve infective endocarditis. We report a case of 30-year-old male with native aortic valve endocarditis who was referred to us for evaluation of worsening of heart failure after an initial period of responsiveness to antibiotics. Detailed evaluation with two-dimensional and three-dimensional transthoracic echocardiography revealed ruptured anterior mitral leaflet aneurysm with severe eccentric mitral regurgitation along with a large vegetation on the aortic valve. The patient underwent successful surgical closure of the defect along with aortic valve replacement.

Cardiac computed tomography angiography results in diagnostic and therapeutic change in prosthetic heart valve endocarditis

Echocardiography may miss prosthetic heart valve (PHV) endocarditis which advocates for novel imaging techniques to improve diagnostic accuracy and patient outcome. The purpose of this study was to determine the complementary diagnostic value of cardiac computed tomography angiography (CTA) to the clinical routine workup including transthoracic and transesophageal echocardiography (TTE/TEE) in patients with suspected PHV endocarditis and its impact on patient treatment. A diagnostic prospective cross-sectional study was chosen as design. Besides clinical routine workup (including TTE/TEE), CTA was performed to assess its diagnostic accuracy and complementary diagnostic/therapeutic value. For the diagnostic accuracy, the reference standard was surgical findings or clinical follow-up. To determine the complementary diagnostic/therapeutic value an expert-panel was used as reference standard. Twenty-eight patients were included. CTA resulted in a major diagnostic change in six patients (21 %) mainly driven by novel detection of mycotic aneurysms by CTA. Furthermore, treatment changes occurred in seven patients (25 %) compared to clinical routine workup. Diagnostic accuracy of routine clinical workup plus CTA was superior to clinical routine workup alone for the detection of PHV endocarditis in general, vegetations and peri-annular extension. This study demonstrates that CTA and clinical workup including TTE and TEE are complementary in patients with PHV endocarditis. Therefore, CTA imaging has to be considered after clinical routine workup in patients with a high suspicion on PHV endocarditis.

Three-dimensional echocardiographic delineation of an acquired aorto-left atrial fistula complicating native aortic valve endocarditis - "advantage of three dimensions"

Aorto-atrial fistulas are rare, but important complications resulting from aortic valve infective endocarditis, aortic valve surgery, or aortic dissection. We hereby report a case of a 20-year male, referred to us with infective endocarditis of the native aortic valve with severe aortic regurgitation and symptoms of heart failure. Detailed evaluation with two-dimensional and three-dimensional transthoracic echocardiography revealed aorto-left atrial fistula secondary to the involvement of the mitral-aortic intervalvular fibrosa (MAIVF) region. The patient underwent successful removal of the vegetations, closure of the defect along with aortic valve replacement, and mitral valve repair.

Transesophageal Echocardiography in Tetralogy of Fallot

Transesophageal echocardiography (TEE) plays an important role in the anatomical, functional, and hemodynamic assessment of patients with congenital heart disease (CHD). This imaging approach has been applied to both children and adults with a wide range of cardiovascular malformations. Extensive clinical experience documents significant contributions, particularly in the perioperative setting. In fact, in the current medical era, many consider this technology to be an essential adjunct to surgical and anesthetic management in CHD. This review focuses on the applications of TEE in patients with tetralogy of Fallot (TOF), the most common form of cyanotic heart disease. Emphasis is given to the perioperative use of this imaging modality and benefits derived during the prebypass and postbypass periods. Limitations and pitfalls relevant to the TEE assessment in patients with this anomaly are also addressed.

Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these techniques sometimes fail to determine the specific cause of PHV dysfunction, which is crucial to the selection of the appropriate treatment strategy. Multidetector-row CT (MDCT) can be of additional value in diagnosing the specific cause of PHV dysfunction and provides valuable complimentary information for surgical planning in case of reoperation. Cardiac magnetic resonance imaging (CMR) has limited value in the evaluation of biological PHV dysfunction. In this Review, we discuss the use of established imaging modalities for the detection of left-sided mechanical and biological PHV dysfunction and discuss the complementary role of MDCT in this context.

Recurrent Pseudomonas aortic root abscess complicating mitral valve endocarditis

We report on a man with Pseudomonas aeruginosa endocarditis causing an aortic root abscess. He underwent surgery with a homograft aortic root replacement and insertion of a tissue aortic valve. The patient then manifested recurrent aortic root infection and respiratory arrest, and eventually succumbed to sepsis. This case highlights the aggressive nature of an uncommon pathogen causing an atypical but lethal form of endocarditis, despite modern medical and surgical treatment.

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.

Infective endocarditis: diagnosis, antimicrobial therapy, and management of complications: a statement for healthcare professionals from the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease in the Young, and the Councils on Clinical Cardiology, Stroke, and Cardiovascular Surgery and Anesthesia, American Heart Association: endorsed by the Infectious Diseases Society of America

BACKGROUND

Despite advances in medical, surgical, and critical care interventions, infective endocarditis remains a disease that is associated with considerable morbidity and mortality. The continuing evolution of antimicrobial resistance among common pathogens that cause infective endocarditis creates additional therapeutic issues for physicians to manage in this potentially life-threatening illness.

METHODS AND RESULTS

This work represents the third iteration of an infective endocarditis "treatment" document developed by the American Heart Association under the auspices of the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease of the Young. It updates recommendations for diagnosis, treatment, and management of complications of infective endocarditis. A multidisciplinary committee of experts drafted this document to assist physicians in the evolving care of patients with infective endocarditis in the new millennium. This extensive document is accompanied by an executive summary that covers the key points of the diagnosis, antimicrobial therapy, and management of infective endocarditis. For the first time, an evidence-based scoring system that is used by the American College of Cardiology and the American Heart Association was applied to treatment recommendations. Tables also have been included that provide input on the use of echocardiography during diagnosis and treatment of infective endocarditis, evaluation and treatment of culture-negative endocarditis, and short-term and long-term management of patients during and after completion of antimicrobial treatment. To assist physicians who care for children, pediatric dosing was added to each treatment regimen.

CONCLUSIONS

The recommendations outlined in this update should assist physicians in all aspects of patient care in the diagnosis, medical and surgical treatment, and follow-up of infective endocarditis, as well as management of associated complications. Clinical variability and complexity in infective endocarditis, however, dictate that these guidelines be used to support and not supplant physician-directed decisions in individual patient management.

Aorto-cavitary fistulous tract formation in infective endocarditis: clinical and echocardiographic features of 76 cases and risk factors for mortality

AIMS

To investigate the clinical features, echocardiographic characteristics, management, and prognostic factors of mortality of aorto-cavitary fistulization (ACF) in infective endocarditis (IE). Extension of infection in aortic valve IE beyond valvular structures may result in peri-annular complications with resulting necrosis and rupture, and subsequent development of ACF. Aorto-cavitary communications create intra-cardiac shunts, which may result in further clinical deterioration and haemodynamic instability.

METHODS AND RESULTS

In a retrospective multi-centre study over 4681 episodes of IE, a total of 76 patients with ACF [1.6%, confidence interval (CI) 95%: 1.2-2.0%] diagnosed by echocardiography or during surgery were identified. Fistulae were found in 1.8% of cases of native valve IE and in 3.5% of cases of prosthetic valve IE from the general population and in 0.4% of drug abusers. PVE was present in 31 (41%) cases of ACF. Transthoracic and transoesophageal echocardiography detected the fistulous tracts in 53 and 97% of cases, respectively. Peri-annular abscesses were detected in 78% of cases, fistulae originated in similar rates from the three sinuses of Valsalva, and the four cardiac chambers were equally involved in the fistulous tracts. Heart failure (HF) developed in 62% of cases and surgery was performed in 66 (87% CI 95% 77-93%) patients with a mortality of 41% (95% CI 30-53%) in the overall population. Multivariate analysis identified HF (OR 3.4, CI 95% 1.0-11.5), prosthetic IE (OR 4.6, CI 95% 1.4-15.4) and urgent or emergency surgical treatment (OR 4.3, CI 95% 1.3-16.6) as variables significantly associated with an increased risk of death. Major complications during follow-up (death, re-operation, or re-admission for HF) among the five operative survivors with residual fistulae occurred in 20 and 100% of patients at 1 and 2 years, respectively.

CONCLUSION

Aorto-cavitary fistulous tract formation is an uncommon but extremely serious complication of IE. In-hospital mortality was exceptionally high despite aggressive management with surgical intervention in the majority of patients. Prosthetic IE, urgent surgery, and the development of HF identify the subgroup of patients with IE and ACF that have significantly increased risk of in-hospital death.

Transesophageal echocardiographic (TEE) evaluation of the aortic valve, left ventricular outflow tract, and pulmonic valve

The most important role of TEE in aortic valve disease is in the diagnosis of endocarditis and its complications. Examination of the annulus and subvalvular region is essential in any patient with possible aortic valve endocarditis. Assessment of the severity of aortic stenosis is a useful application of TEE when other data are either inconsistent or unavailable. TEE can provide a diagnosis of the origin of acute severe aortic insufficiency; this information may play a critical role in surgical planning. The diagnosis of a variety of aortic valve diseases can be made when TEE is performed to find an embolic source or to rule out dissection. In the case of mass lesions, such as papillary fibroelastomas and Libman-Sacks vegetations, the results of TEE carry major therapeutic implications. TEE offers generally excellent quality images of the LVOT and images of the RVOT and pulmonic valve that are superior to transthoracic echocardiography. The major clinical usefulness of TEE stems from its ability to identify pulmonic valve mass lesions and the causes of left and right ventricular outflow obstruction. TEE is also an important adjunct in the surgical management of left ventricular outflow obstruction.

Aorto-Left Atrial Fistula Complicating Native Aortic Valve Endocarditis

A 21-year-old male with native aortic valve Streptococcus viridans endocarditis was found to have an aorto-left atrial fistula by transthoracic echocardiography. He underwent successful fistula plication and aortic valve replacement.

Pseudoabscess of the aortic root caused by ectopic seating of an aortic prosthesis

An approach to some of the technical problems involved in aortic valve replacement includes positioning of some or all of the prosthetic ring in a position ectopic to the true aortic annulus. Such placement can create the apparent appearance of an echolucent region adjacent to the prosthetic ring that shows flow on color Doppler interrogation to suggest the presence of an abscess cavity. This case demonstrates how such a pseudoabscess can be created and the clinical and echocardiographic clues that were used to make the correct diagnosis.

Use of transesophageal echocardiography to detect unsuspected massive pulmonary emboli

This report describes three patients in whom unsuspected large central pulmonary emboli were identified by transesophageal echocardiography. We discuss the utility and limitations of transesophageal echocardiography in diagnosing pulmonary emboli and its potential beneficial impact on the management of patients in the intensive care unit, particularly those with unexplained hypotension.

Aortic root abscess with fistula formation

Aortic root abscess is a common complication of aortic valve endocarditis. However, aortic root abscess and formation of a fistula from the aortic root to the right ventricular outflow tract in the setting of a native aortic valve and previous repair of an aortic dissection with a Dacron graft is an uncommon event. Transesophageal echocardiography is superior to transthoracic echocardiography for the diagnosis of aortic root abscess. To our knowledge, no studies have compared the diagnostic value of cardiac MRI with transesophageal echocardiography for this condition.

Perivalvular cavities in endocarditis: abscesses versus pseudoaneurysms? A transesophageal Doppler echocardiographic study in 118 patients with endocarditis

The appearance of perivalvular cavities (PCs) in patients with infectious endocarditis (IE) was studied by transesophageal echocardiography (TEE) color Doppler examinations to determine whether the color Doppler TEE presentation was in keeping with the current concept of PCs representing abscesses. Two heart centers participated in the study. Videotape recordings of TEE examinations in patients with IE were analyzed retrospectively for 18 months in both centers, and one center included patients prospectively for an additional 18 months. A total of 118 patients with a diagnosis of IE based on TEE and clinical and laboratory findings were seen during the study period. TEE showed PCs in 34 patients. In 3 patients who died, no autopsy was performed; the PCs were proved at autopsy or surgery in the remaining 31 patients, who constituted the study population. All PCs were echo free at TEE. Apart from one technically inadequate examination, all PCs contained color Doppler signals indicating intracavitary blood flow; the PCs communicated through a narrow channel with high-pressure regions (the left ventricle or the ascending aorta). At surgery or autopsy, only 2 of the 31 patients had pus accumulations besides the blood-filled PCs. At TEE the pus accumulations presented as echo-rich, shaggy tissue thickening. It is concluded that well-delineated, echo-free PCs with intracavitary color Doppler signals at TEE appear to be pseudoaneurysms, and therefore the term abscess should not be used in these cases. Although further studies are needed, our findings suggest that PCs more likely occur by infectious tissue weakening and subsequent dissection rather than as a result of primary abscess formation with secondary rupture.(ABSTRACT TRUNCATED AT 250 WORDS)