Comparison of transesophageal and transthoracic echocardiography for diagnosis of right-sided cardiac lesions

Value of Time-Resolved Cardiac CT in Children and Young Adults with Congenital Heart Disease and Infective Endocarditis

BACKGROUND

Diagnosis of infective endocarditis (IE) can be challenging due to negative blood cultures and diagnostic limitations of various imaging modalities. Transesophageal echocardiography (TEE) is the gold standard imaging modality for visualization of valvular vegetations. However, due to the anterior location of the pulmonary valve, post-surgical changes, and sedation requirement, TEE can be challenging in the pediatric population. The aim of this study was to assess the value of Cardiac CT (CCT) for diagnosis of IE in children and young adults with congenital heart disease (CHD).

METHODS

This is a single-center retrospective study of pediatric patients with CHD and diagnosis of IE who underwent CCT from 2018 to 2022. Data collected included age, gender, cardiac diagnosis, clinical presentation, echocardiographic/CCT findings, and blood culture results. In addition, modified Duke criteria (MDC) for the diagnosis of IE were applied with and without CCT findings as the diagnostic imaging criterion.

RESULTS

Fourteen patients were included in this study with a median age of 11 years old. Nine patients were female. Ten patients had IE of the RV-PA conduit and four patients had IE of the aortic valve. Using MDC, 4 patients had definite IE. After including CCT findings, 11 patients (79%) met MDC for definite IE. Blood cultures were positive in 12 patients. CCT revealed the following complications: thromboembolic findings/pseudoaneurysms in 5 patients each and prosthetic valve perforation/prosthetic valve leak in one patient each.

CONCLUSIONS

This study reinforces the complimentary role of CCT to echocardiography in the work-up and diagnosis of IE in patients with CHD. With further improvement in lowering radiation exposure, CCT may have a key role in the diagnostic work-up of endocarditis and could be implemented in the diagnostic criteria of IE.

Right-sided Infective Endocarditis with Ventricular Free Wall Vegetation Caused by Abiotrophia defectiva in a Patient with Unrepaired Ventricular Septal Defect

To our knowledge, there have been no reports of right-sided infective endocarditis (RSIE) with ventricular free wall vegetation caused by Abiotrophia defectiva. We herein report a case of RSIE caused by A. defectiva with ventricular free wall vegetation in a 27-year-old man with ventricular septal defect (VSD). Computed tomography showed multiple bilateral pulmonary nodular shadows. Transesophageal echocardiography (TEE) demonstrated right ventricular free wall vegetation at the jet stream. Blood culture revealed A. defectiva. These findings are consistent with a diagnosis of infective endocarditis and septic pulmonary embolism. Treatment with ceftriaxone and gentamicin and subsequent surgical VSD closure improved the patient's condition without recurrence.

Inaccuracy of transthoracic echocardiography for the identification of right‐sided vegetation in patients with no history of intravenous drug abuse or cardiac device insertion

Objective:

The use of transthoracic echocardiography (TTE) to identify right-sided infective endocarditis (RSIE) vegetation is controversial. Data are scarce for patients with no history of intravenous drug abuse (IVDA) or cardiac device insertion. This study analysed the consistency of presurgical echocardiographic results with surgical findings for vegetation identification, and the factors that influence accuracy of echocardiography.

Methods:

This retrospective trial divided infective endocarditis (IE) patients into three subgroups according to the results of their presurgical TTE: left-sided native IE (LSNIE), left-sided prosthetic valve IE (LSPIE) and RSIE. The accuracy of TTE was tested by comparing vegetation (number and location), detected presurgery by TTE, with actual findings during surgery.

Results:

In total, 416 patients were analysed, 322 with LSNIE, 31 with LSPIE and 63 with RSIE. Consistency between TTE findings and surgical results was lower in the RSIE group compared with the LSPIE and LSNIE groups. Consistency was lowered by the presence of vegetation in multiple locations and atypical distribution – both of which were increased in the RSIE group. The chance of vegetation in both sides of the heart rose with increased numbers of vegetation locations in RSIE patients. A high proportion of RSIE patients had congenital heart defects, mostly ventricular septal defects.

Conclusions:

TTE may be unsuitable for RSIE patients with no history of IVDA or cardiac device insertion, because multifocal and atypically distributed vegetation may influence detection accuracy.

Native valve right sided infective endocarditis

Right-sided infective endocarditis (RSIE) accounts for 5-10% of all cases of infective endocarditis (IE), and is predominantly encountered in the injecting drug user (IDU) population, where HIV and HCV coinfections often coexist. Staphylococcus aureus is the most common pathogen. The pathogenesis of RSIE is still not well understood. RSIE usually presents as a persistent fever with respiratory symptoms whilst signs of systemic embolisation as seen in left-sided IE are notably absent. The prompt diagnosis of RSIE thus requires a high index of suspicion. Transthoracic echocardiography (TTE) can detect the majority of RSIE, whilst transoesophageal echocardiography (TOE) can increase sensitivity. Virulence of the causative organism and vegetation size are the major determinants of prognosis. Most cases of RSIE resolve with appropriate antibiotic administration.

Cardiac imaging in infectious endocarditis

Infectious endocarditis remains both a diagnostic and a treatment challenge. A positive outcome depends on a rapid diagnosis, accurate risk stratification, and a thorough follow-up. Imaging plays a key role in each of these steps and echocardiography remains the cornerstone of the methods in use. The technique of both transthoracic echocardiography and transoesophageal echocardiography has been markedly improved across the last decades and most recently three-dimensional real-time echocardiography has been introduced in the management of endocarditis patients. Echocardiography depicts structural changes and abnormalities in the heart, but it does not uncover the underlying pathophysiological processes at the cellular or molecular level. This problem is addressed with introduction of new molecular imaging methods as (18)F-fluorodesoxyglucose ((18)F-FDG) PET-CT and single photon emission computed tomography fused with conventional CT (SPECT/CT). Of these methods, (18)F-FDG PET-CT carries the best promise for a future role in endocarditis. But there are distinct limitations with both SPECT/CT and (18)F-FDG PET-CT which should not be neglected. MRI and spiral CT are methods primarily used in the search for extra cardial infectious foci. A flowchart for the use of imaging in both left-sided and right-sided endocarditis is suggested.

Update on echocardiography in the management of infective endocarditis

Echocardiography is the major imaging modality used for the diagnosis of infective endocarditis (IE). It is also useful in detecting the complications of IE which often necessitate surgical intervention and strongly influence patient outcomes. Transesophageal echocardiography (TEE), with proven superiority over transthoracic echocardiography (TTE) for the detection of vegetations and complications such as abscess, should be performed in the vast majority of cases especially when TTE image quality is poor or implanted devices are present. Three-dimensional (3D) TEE provides enhanced display of anatomic-spatial relationships allowing more precise delineation of complex pathology, particularly of the mitral valve and annulus. Importantly, echocardiographic findings can be non-specific and should always be interpreted in the context of the pre-test probability of IE based on careful clinical assessment. IE remains a challenging disease associated with variable clinical presentations, and high mortality. Whenever IE is suspected, echocardiography should be utilized early for both diagnosis and detection of complications.

Role of transthoracic and transesophageal echocardiography in right-sided endocarditis: one echocardiographic modality does not fit all

The added value of transesophageal echocardiography (TEE) over transthoracic echocardiography in the assessment of left-sided infective endocarditis has been extensively validated in the literature. Little research has dealt with the role of echocardiography in right-sided infective endocarditis (RSE), however. In this review, the differences between RSE and left-sided endocarditis and the different types of RSE according to the types of patients who have the disease are described. Both issues have important implications for echocardiographic workup. Moreover, a systematic echocardiographic protocol to avoid missing right-sided vegetations and several specific morphologic aspects of RSE are reviewed. Normal right-sided structures, which may mimic vegetations, particularly when the clinical picture is compatible, are described. Finally, the value of transthoracic echocardiography and TEE in RSE is reviewed according to the publications available. The diagnostic yield of transthoracic echocardiography is comparable with that of TEE in intravenous drug users. On the contrary, TEE is mandatory in patients with cardiac devices. A Bayesian-based diagnostic approach is proposed for a third poorly characterized group of patients with RSE who are not drug addicts, have no cardiac devices, and have no left-sided endocarditis (the "three no's" endocarditis group).

Eustachian valve endocarditis: detection with multiplane transesophageal echocardiography

Right-sided involvement is fairly common in infective endocarditis, but involvement of the eustachian valve is distinctly rare. We present the case of a 36-year-old intravenous drug user with staphylococcal bacteremia and septic pulmonary emboli. Transthoracic echocardiography was normal, but transesophageal echocardiography revealed a large eustachian valve vegetation. This case illustrates the utility of multiplane transesophageal echocardiography in the evaluation of eustachian valve pathology.

A rare localization in right-sided endocarditis diagnosed by echocardiography: a case report

BACKGROUND

Right-sided endocarditis occurs predominantly in intravenous drug users, patients with pacemakers or central venous lines and with congenital heart diseases. The vast majority of cases involve the tricuspid valve.

CASE PRESENTATION

A case of a 31-year-old woman with intravenous drug abuse who had a right-sided vegetation attached to the muscular bundle of the right ventricle is presented. Transthoracic echocardiography revealed a vegetation in the right ventricular outflow tract. Transesophageal echocardiography clearly showed that the 1.8 cm vegetation was not adherent to the pulmonary valve but attached to a muscular bundle.

CONCLUSIONS

Our case points to an unusual location of right-sided endocarditis in intravenous drug users. It confirms that TTE remains an easy and highly sensitive first-line examination for the diagnosis of right-sided endocarditis.

Usefulness of motion patterns indentified by tissue Doppler echocardiography for diagnosing various cardiac masses, particularly valvular vegetations

This study sought to test whether anomalous cardiac and aortic structures can be differentiated from native tissue and artifacts by physical properties of tissue motion using transesophageal tissue Doppler echocardiography (TDE). TDE was employed in 85 consecutive patients after anomalous structures had been detected by conventional transesophageal echocardiography (TEE). The control group consisted of 40 randomized patients. Certainty of diagnosis was divided into 4 categories, and TDE signals were related to particular anomalous structures by a blinded second observer. A mechanical model of a beating ventricle was constructed and suspended in a water bath. Synthetic material was utilized to simulate anomalous intracavitary structures with varying shape, consistency, and attachment. Incoherent motion was present in endocarditic vegetations, freely oscillating thrombi, fourth-degree aortic plaques, Chiari network, valvular prolapse, tumors, and in normal valve leaflets and papillary muscles. Within 15 seconds vegetations could be detected in 17 patients (68%) using TDE versus 5 patients (20%) using only conventional imaging. Coherent motion with a phase difference occurred due to damped oscillation. This phenomenon occurred in 5 patients with thrombi of the left atrial appendage (100%), in 3 ventricular clots (75%), and in 2 hypernephroma in the right atrium (100%). Rapid identification of clots could be achieved in 15 patients (71%) versus 12 patients (57%). Concordant motion was shown in third-degree aortic plaques, postrheumatic valvular lesions, and aortic intramural hematomas, but diagnostic benefit could not be demonstrated. In 41 patients (48%) histopathologic and intraoperative results confirmed echocardiographic findings. Motion patterns could be reproduced independently of the heart rate by model experiments. This study demonstrates that TDE expedites the detection of vegetations in infective endocarditis. Diagnostic certainty can be increased as well for thrombus formations.

The role of transesophageal echocardiography in the diagnosis and treatment of right atrial thrombi

Twenty patients with right atrial thrombi were identified through the use of transthoracic and transesophageal echocardiography. Transesophageal echocardiography identified right atrial thrombi in all 20 cases. Transthoracic echocardiography showed definite thrombi in only 6 (30%) cases and suggested thrombus in another 2 (10%) patients. Thus transthoracic echocardiography results were false-negative for right atrial thrombus in 60% of cases. All 3 thrombi found within the right atrial appendage and 2 of 3 thrombi on pacemaker wires were missed by transthoracic echocardiography. There was no significant difference in the mean size between those thrombi seen (1.37 +/- 0.6 cm) and those missed (1.5 +/- 0.9 cm) by transthoracic echocardiography. Transesophageal echocardiography also significantly affected treatment. Anticoagulation was initiated or amplified in 13 patients. In 8 of these 13, thrombi were seen only by transesophageal echocardiography. Surgery was performed to remove thrombi in 7 cases, and in 3 (43%) cases it was because of thrombi seen only by transesophageal echocardiography. This study suggests that transesophageal echocardiography should be performed whenever right atrial thrombi are suspected. Transesophageal echocardiography has a significant effect on the diagnosis and management of patients with right atrial thrombi.

Multiplane transesophageal echocardiographic evaluation of transvenous defibrillation leads

Permanent transvenous cardioverter-defibrillator leads were investigated by multiplane transesophageal echocardiography (TEE) (1) to determine whether intracardiac lead segments can be visualized, (2) to verify the position of the coils, and (3) to detect possible thrombus formation. The diagnostic information obtained in 62 patients by TEE was compared to that of transthoracic echocardiography (TTE). Abnormal findings were only visualized by multiplane TEE. However, further controlled studies are needed to determine the clinical relevance of displaced caval (one patient) and ventricular coils (15 patients), ventricular (1 patient) or atrial (6 patients) loops, and of clinically uneventful thrombi (13 patients).

Application of transthoracic and transesophageal echocardiography in the diagnosis and management of infective endocarditis

Infective endocarditis continues to be a cause of significant cardiac morbidity and mortality. To improve the prognosis of patients with this disorder, early diagnosis is crucial but difficult to establish on the basis of clinical parameters alone. Echocardiography, both transthoracic and transesophageal techniques, has a major role in the detection of vegetations that are the hallmark of endocarditis. Valvular and perivalvular complications can also be well assessed by echocardiography. With the improved resolution provided by recent technologic advances in echocardiography, vegetations can be reliably detected in most patients with endocarditis. We propose that present diagnostic criteria for endocarditis be revised to include echocardiographic findings as a major parameter in the diagnosis. Finally, a diagnostic approach incorporating transthoracic and transesophageal echocardiography in these patients will be discussed taking into consideration the different degrees of clinical suspicion for the existence of the disease.

Superiority of transoesophageal echocardiography in detection of multichambered multiple myxoma

We describe a rare case of a sporadiac form of multiple myxoma and highlight the unusual combination of left atrial and right ventricular tumors. Transoesophageal echocardiography proved superior to precordial imaging in detecting all four masses (two in left atrium and two in right ventricle).