Lambl's Excrescences: Current Diagnosis and Management

Echocardiography in Endocarditis

Infective endocarditis (IE) continues to have high rates of adverse outcomes, despite recent advances in diagnosis and management. Although the use of computer tomography and nuclear imaging appears to be increasing, echocardiography, widely available in most centers, is the recommended initial modality of choice to diagnose and consequently guide the management of IE in a timely-dependent fashion. Echocardiographic imaging should be performed as soon as the IE diagnosis is suspected. Several factors may delay diagnosis, for example, echocardiography findings may be negative early in the disease course. Thus, repeated echocardiography is recommended in patients with negative initial echocardiography if high suspicion for IE persists in patients at high risk. However, systematic echocardiographic screening should not be utilized as a common tool for fever, but only in the presence of a reasonable clinical suspicion of IE. It may increase the risk of false-positive rates of patients requiring IE therapy or may exacerbate diagnostic uncertainty about subtle findings. Considering the complexity of the disease, the echocardiographic use should be increasingly time-efficient and should focus on the correct identification of IE lesions and associated complications. The path to identify patients who need surgery passes through an echocardiographic skill ensuring the identification of the cardiac anatomical structures and their involvement in the destructive infective extension. We pointed out the role of echocardiography focused on the correct identification of IE distinctive lesions and the associated complications, as part of a diagnostic strategy, within an integrated multimodality imaging, managed by an "endocarditis team".

A Large Lambl's Excrescence Causing Embolic Stroke in a Young Patient: A Case Report and Review of Literature

Lambl's excrescences (LEs) are thin, filiform and hypermobile strands that develop at the valvular coaptation sites of the heart. Since first described in 1856 by Vilém Dušan Lambl, there has been an increasing number of reports of central and peripheral emboli arising from cardiac LEs. LEs have been linked to ischemic strokes irrespective of age and comorbidities. We report one of the youngest reported cases in literature of an embolic stroke in a 25-year-old woman caused by a LE. A comprehensive workup was performed that revealed a large aortic valve LE. The patient was discharged on dual anti-platelet therapy with outpatient cardiology follow-up for surveillance echocardiograms. We then surveyed the literature and reviewed case reports and observational studies of LEs linked to systemic emboli. We found that most LEs are present on left-sided high-pressure valves especially the ventricular aspect of the aortic valves and that most reported cases of cerebral embolism had aortic valve LEs. The management of cardioembolic stroke secondary to LEs remains unclear. LEs have not been identified as a definite etiology of cardioembolic strokes warranting the need for large-scale studies to help guide the management of cardiac LEs in the setting of ischemic stroke.

Lambl's Excrescence and Management of Recurrent Cerebrovascular Accident (CVA)

Lambl's excrescence is a rare valvular finding of uncertain pathologic significance. This case describes a previously healthy 42-year-old woman experiencing a sudden onset of word-finding difficulty. MRI of the brain demonstrated acute and chronic infarcts, prompting echocardiography, which revealed Lambl's excrescence of the aortic valve.

Use of Three-Dimensional Echocardiography to Identify an Unusual Cause of Aortic Regurgitation

•New-onset AR after coronary angiography should raise suspicion for AV injury. •Consider 3D imaging if no clear etiology found with 2D imaging. •Three-dimensional imaging showed a partial tear of RCC. •Medical intervention was altered based in part on TEE findings.

Role of echocardiography in the diagnosis and clinical management of infective endocarditis

Infective endocarditis (IE) is a deadly disease, constituting both diagnostic and treatment challenges. A positive outcome requires rapid and accurate diagnosis, and for that, echocardiography unequivocally remains the cornerstone. Transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) have complementary roles and have been markedly improved during the last decades. The transthoracic modality is the recommended first-line approach but may only be sufficient in patients where the probability of IE is low and/or with clear acoustic windows, especially in patients with right-sided IE. The transesophageal modality is superior to TTE in most aspects and is recommended for all other patients. Both TTE and TEE may delineate vegetation location and size, assess for paravalvular extension of infection, and have the added advantage of defining the hemodynamic effects of valvular or device infection. However, echocardiography still has significant limitations, and novel imaging techniques are increasingly being exploited to improve diagnostic potential. Cardiac computed tomography (CT) performs better than TEE in the detection of abscess or pseudoaneurysm, while magnetic resonance imaging (MRI) has limited value in the diagnostic phase of IE but adds knowledge to the evaluation of extracardiac events. Nuclear molecular techniques are evolving as key supplementary methods in difficult-to-diagnose cases. Although newer imaging modalities are undergoing preliminary evaluation and multimodal imaging will play an increasing role in IE, echocardiography will continue to be pivotal in patients with IE for the foreseeable future.

Cardiac Computed Tomography of Native Cardiac Valves

Valvular heart disease (VHD) is a significant clinical problem associated with high morbidity and mortality. Although not being the primary imaging modality in VHD, cardiac computed tomography (CCT) provides relevant information about its morphology, function, severity grading, and adverse cardiac remodeling assessment. Aortic valve calcification quantification is necessary for grading severity in cases of low-flow/low-gradient aortic stenosis. Moreover, CCT details significant information necessary for adequate percutaneous treatment planning. CCT may help to detail the etiology of VHD as well as to depict other less frequent causes of valvular disease, such as infective endocarditis, valvular neoplasms, or other cardiac pseudomasses.

Coexistence Case of Papillary Fibroelastoma and Lambl's Excrescence of the Left Heart, Which Is Occasionally Associated with Significant Stroke

Papillary fibroelastoma (PFE) is a benign tumor that arises mostly from left-sided valves. PFE can cause stroke, and surgical resection may be needed. Lambl's excrescence (LE) is a filiform valvular lesion and is considered a possible cause of stroke. A 79-year-old man with light-headedness and left-sided hemiparesis was diagnosed with stroke. Transesophageal echocardiography (TEE) revealed a round-shaped mobile mass in the left ventricular outflow tract (LVOT), which was considered the cause of the stroke. Surgical resection was performed transaortically, and during surgery, a mass was incidentally detected on the noncoronary cusp (NCC), which was also resected followed by aortic valve replacement. Pathology confirmed that the mass in the LVOT was a PFE and that the filiform mass on the NCC was LE. We herein report a rare case of PFE in the LVOT and coexisting LE on the NCC. A careful examination via TEE helps to identify other possible causes of stroke hidden behind the obvious cause.

Multimodality Imaging of Infective Endocarditis

Infective endocarditis (IE) is a complex multisystemic disease resulting from infection of the endocardium, the prosthetic valves, or an implantable cardiac electronic device. The clinical presentation of patients with IE varies, ranging from acute and rapidly progressive symptoms to a more chronic disease onset. Because of its severe morbidity and mortality rates, it is necessary for radiologists to maintain a high degree of suspicion in evaluation of patients for IE. Modified Duke criteria are used to classify cases as "definite IE," "possible IE," or "rejected IE." However, these criteria are limited in characterizing definite IE in clinical practice. The use of advanced imaging techniques such as cardiac CT and nuclear imaging has increased the accuracy of these criteria and has allowed possible IE to be reclassified as definite IE in up to 90% of cases. Cardiac CT may be the best choice when there is high clinical suspicion for IE that has not been confirmed with other imaging techniques, in cases of IE and perivalvular involvement, and for preoperative treatment planning or excluding concomitant coronary artery disease. Nuclear imaging may have a complementary role in prosthetic IE. The main imaging findings in IE are classified according to the site of involvement as valvular (eg, abnormal growths [ie, "vegetations"], leaflet perforations, or pseudoaneurysms), perivalvular (eg, pseudoaneurysms, abscesses, fistulas, or prosthetic dehiscence), or extracardiac embolic phenomena. The differential diagnosis of IE includes evaluation for thrombus, pannus, nonbacterial thrombotic endocarditis, Lambl excrescences, papillary fibroelastoma, and caseous necrosis of the mitral valve. The location of the lesion relative to the surface of the valve, the presence of a stalk, and calcification or enhancement at contrast-enhanced imaging may offer useful clues for their differentiation. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Echocardiographic Evaluation of Cardiac Masses

PURPOSE OF REVIEW

Cardiac masses encompass a broad range of etiologies and are often initially revealed by echocardiography. The differential may change depending on the location of the mass and patients' medical history or presentation. It is important for clinicians to be aware of subtle visual characteristics on echocardiography in order to correctly diagnose the pathology.

METHODS

Patients who underwent transthoracic echocardiography and were found to have one or more cardiac masses between January 1, 2020, and May 15, 2023, were reviewed. Their demographic data, clinical presentation, medical history, imaging, and follow-up information were collected from hospital electronic medical records, de-identified, and used to complete this review paper. A detailed review of cardiac masses divided by cardiac chamber accompanied by real-world echocardiographic images from patients in a large inner city public hospital. We hope that this systematic review of cardiac masses with real-world echocardiographic images will help clinicians note subtle echocardiographic characteristics to aid in the diagnosis and treatment of cardiac masses.

Advances in Cardiac Workup for Transient Ischemic Attack: Improving Diagnostic Yield and Reducing Recurrent Stroke Risk

Transient ischemic attack (TIA) is a warning sign for an impending stroke, with a 10-20% chance of a stroke occurring within 90 days of the initial event. Current clinical practice for cardiac workup in TIA includes cardiac enzymes, with 12-lead electrocardiogram, transthoracic echocardiography, and 24-hour Holter monitoring. However, the diagnostic yield of these investigations is variable, and there is a need for better diagnostic approaches to increase the detection of cardiac abnormalities in a cost-effective way. This review article examines the latest research on emerging diagnostic tools and strategies and discusses the potential benefits and challenges of using these advanced diagnostic approaches in clinical practice. Novel biomarkers, imaging techniques, and prolonged rhythm monitoring devices have shown great promise in enhancing the diagnostic yield of cardiac workup in TIA patients. Echocardiography, Transcranial Doppler ultrasound, cardiac MRI, and cardiac CT are among the promising diagnostic tools being studied. We conclude the article with a suggested diagnostic algorithm for cardiac workup in TIA. Further research is necessary to enhance their usefulness and to outline future directions for research and clinical practice in this field.

Lambl's Excrescence as an Etiology of Thromboembolism: Case Report and Literature Review

Lambl's excrescence (LE), a rare thin linear fibrous thread of collagen and elastic fibrous tissue originating at closure margins of heart valve leaflets is considered a rare cause of thromboembolism, causing ischemic stroke, transient ischemic attack (TIA), acute coronary syndrome, or peripheral thromboembolism. The gold standard for diagnosing LE is transesophageal echocardiography (TEE). Due to the rarity of the disease and lack of significant research, no guidelines exist about the management of LE. Twenty-two papers about LE were reviewed, focusing on the management aspect aiming to assist in guideline publication. Articles were retrieved using PubMed database using "Lambl's excrescences" as a keyword. All free full text papers up to 2023 were retrieved. In this report, we present the first publication of a case of a TIA secondary to LE in the United Arab Emirates. A 53-year-old male presented with transient attacks of left monocular blindness with complete recovery 2 days later. Extensive stroke work-up was negative, except for TEE, which showed an echo-dense linear mobile structure attached to the aortic surface of the aortic valve closure margin, suggesting LE. As no guidelines exist on the management of LE, the patient was started on Clopidogrel 75 mg daily and remained asymptomatic for 2 years. After reviewing the literature, we suggest the use of Aspirin for patients with ⩾1 embolic event attributed to LE while not on antiplatelets or anticoagulants, as it is the most used and recommended treatment option and is effective in preventing recurrent thromboembolic events.

Child Neurology: Case Report of Lambl Excrescences in a Pediatric Patient With Multifocal Strokes

Lambl excrescences are fibrinous connective tissue strands found predominantly on left-sided cardiac valves. These valvular strands are typically benign, but have been implicated as a potential etiology of embolic strokes in adult patients. The significance of Lambl excrescences in pediatric stroke cases is unclear and not previously reported in the literature. In this study, we describe a 10-year-old boy who presented with acute-onset right-sided hemiplegia, found to have multifocal embolic strokes of various ages. Extensive stroke workup was unrevealing, aside from the presence of small, filamentous, strand-like densities associated with the mitral and aortic valves noted on a transesophageal echocardiogram consistent with Lambl excrescences. In this case report, we review Lambl excrescences and their significance in acute stroke and management options for the prevention of future ischemia in these patients.

Lambl's excrescence and the safety of radiofrequency ablation for atrial fibrillation

BACKGROUND

Lambl's excrescences (LEs) are excrescences with an extremely low incidence, mainly ultrasound diagnosed. Increasingly, LEs are detected by transesophageal echocardiography before catheter ablation, which raises safety concerns on whether LEs were associated with an embolism event during or after ablation, but clinical data are still lacking.

METHODS AND RESULTS

We consecutively recruited 8081 patients with atrial fibrillation who underwent radiofrequency catheter ablation in Beijing Anzhen Hospital from Jan 1, 2017 to Dec 31, 2019. Total 21 patients (0.3%) were diagnosed as LEs with an average age of 70.8 ± 8.9 years, and 38.1% were male. Persistent atrial fibrillation (PeAF) and paroxysmal atrial fibrillation (PAF) accounted for 57.1% (12 cases) and 42.9% (nine cases), respectively. LEs were mostly frequently observed on the aortic valve (18 cases, 75%) and mitral valve (six cases, 25%). Precisely, the noncoronary cusp is ranked first in terms of the LEs presence (seven cases, 29.2%), followed by the right coronary cusp (six cases, 25.0%), the left coronary cusp (five cases, 20.8%), the anterior mitral valve (four cases, 16.7%), and the posterior mitral valve (two cases, 8.3%). During the ablation for LEs patients, the average procedure time was 96.0 ± 22.4 min; the average fluoroscopy time was 4.2 ± 0.8 min; the average total ablation time was 20.6 ± 5.6 min; and the mean hospital stay was 3.3 ± 0.6 days. No patients suffered from serious complications during the procedure. Furthermore, no cardiovascular event was observed during a follow-up of 19.1 ± 11.8 months.

CONCLUSIONS

There was no clear association between LEs with intraoperative embolism events or cardiovascular events during the follow-up period.

[A case of recurrent cerebral embolism associated with Lambl's excrescence]

A 75-year-old female had a history of prior ischemic stroke with aphasia and right hemiplegia. Magnetic resonance angiography showed left internal carotid artery occlusion. She was successfully treated with intravenous recombinant tissue plasminogen activator (IV t-PA) and underwent endovascular thrombectomy (EVT). She was diagnosed with cardioembolic stroke due to the presence of atrial fibrillation and mitral valve stenosis, and warfarin was administered. However, she experienced large vessel occlusion twice within 2 years. Upon further analysis, transesophageal echocardiography revealed a mobile hyperechoic structure on the aortic valve, which was assumed to be an embolic source. Thus, we decided to perform mitral and aortic valve replacement. The excised aortic valve structure was suggested to be an example of Lambl's excrescence, histopathologically. After surgery, the patient had no recurrence for 3 years. Several cases of ischemic stroke associated with Lambl's excrescence have been reported, but definitive guidelines for managing patients with Lambl's excrescence do not currently exist. Surgical intervention for Lambl's excrescence with recurrent ischemic events may be important for preventing further recurrence.

Teleost fish: a new spontaneous model for the study of Lambl's excrescences

Lambl's excrescences (LE) are fibrous strands typically occurring at coaptation lines of cardiac valves. Although they have been widely reported in human medicine, information on LE occurrence in veterinary medicine is still scarce. The present study aimed to investigate the presence of LE in different freshwater fish and in swordfish. A total of 185 hearts were collected from different fish species, and samples of different cardiac areas (sinus venosus, atrial wall with sinoatrial valves, ventricular wall with atrioventricular valves and bulb with bulboventricular valves) were submitted to histopathological evaluation. LE were detected in 6 of 103 freshwater fish (5.8%) and 19 of 82 swordfish (23.2%). LE developed in atrioventricular, sinoatrial and bulboventricular valves. All affected valves also showed endocardiosis. Based on the results of the present work, teleost fish, specifically swordfish, could be proposed as a novel spontaneous model for the study of LE pathogenesis.

Multimodality Imaging of the Anatomy of the Aortic Root

The aortic root has long been considered an inert unidirectional conduit between the left ventricle and the ascending aorta. In the classical definition, the aortic valve leaflets (similar to what is perceived for the atrioventricular valves) have also been considered inactive structures, and their motion was thought to be entirely passive—just driven by the fluctuations of ventricular–aortic gradients. It was not until the advent of aortic valve–sparing surgery and of transcatheter aortic valve implantation that the interest on the anatomy of the aortic root again took momentum. These new procedures require a systematic and thorough analysis of the fine anatomical details of the components of the so-called aortic valve apparatus. Although holding and dissecting cadaveric heart specimens remains an excellent method to appreciate the complex “three-dimensional” nature of the aortic root, nowadays, echocardiography, computed tomography, and cardiac magnetic resonance provide excellent images of cardiac anatomy both in two- and three-dimensional format. Indeed, modern imaging techniques depict the aortic root as it is properly situated within the thorax in an attitudinally correct cardiac orientation, showing a sort of “dynamic anatomy”, which admirably joins structure and function. Finally, they are extensively used before, during, and after percutaneous structural heart disease interventions. This review focuses on the anatomy of the aortic root as revealed by non-invasive imaging techniques.

Acute myocardial infarction from embolization of Lambl's excrescences: A case report

While coronary artery embolism remains an infrequent cause of myocardial infarction (MI), it may present in patients at otherwise low risk for coronary artery disease. When clinicians apply typical risk stratification in these cases, they may be led away from a full evaluation for acute coronary syndrome (ACS). A diagnosis of MI in an otherwise healthy patient should prompt consideration of embolic sources, including Lambl's excrescences (LEs), and echocardiographic evaluation may be necessary to make a final diagnosis. We present a case of LEs in an otherwise healthy 43-year-old male presenting with chest pain and elevated cardiac enzymes, and also review the cases of this rare event found in the literature.

An Autopsy Case of Lambl's Excrescences with Trousseau Syndrome that Caused Cardioembolic Stroke

The frequency and risk of embolism by Lambl's excrescences (LEs) remain unclear. We herein report an autopsy case of LEs that caused cardioembolic stroke. A 74-year-old man with colon cancer was hospitalized for ischemic stroke. His D-dimer levels were elevated. Thus, a diagnosis of ischemic stroke with Trousseau syndrome was made. At the autopsy, we found LEs in the aortic valves and thromboembolism of the brain blood vessels. This finding demonstrated that fibrin clots had adhered to the LEs because of coagulation abnormalities associated with Trousseau syndrome and became embolized. This case highlights the risk of LEs in patients with coagulation abnormalities.