Relationship between Lambl's excrescences and embolic strokes of undetermined source

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.

Embolic strokes of undetermined source: a clinical consensus statement of the ESC Council on Stroke, the European Association of Cardiovascular Imaging and the European Heart Rhythm Association of the ESC

One in six ischaemic stroke patients has an embolic stroke of undetermined source (ESUS), defined as a stroke with unclear aetiology despite recommended diagnostic evaluation. The overall cardiovascular risk of ESUS is high and it is important to optimize strategies to prevent recurrent stroke and other cardiovascular events. The aim of clinicians when confronted with a patient not only with ESUS but also with any other medical condition of unclear aetiology is to identify the actual cause amongst a list of potential differential diagnoses, in order to optimize secondary prevention. However, specifically in ESUS, this may be challenging as multiple potential thromboembolic sources frequently coexist. Also, it can be delusively reassuring because despite the implementation of specific treatments for the individual pathology presumed to be the actual thromboembolic source, patients can still be vulnerable to stroke and other cardiovascular events caused by other pathologies already identified during the index diagnostic evaluation but whose thromboembolic potential was underestimated. Therefore, rather than trying to presume which particular mechanism is the actual embolic source in an ESUS patient, it is important to assess the overall thromboembolic risk of the patient through synthesis of the individual risks linked to all pathologies present, regardless if presumed causally associated or not. In this paper, a multi-disciplinary panel of clinicians/researchers from various backgrounds of expertise and specialties (cardiology, internal medicine, neurology, radiology and vascular surgery) proposes a comprehensive multi-dimensional assessment of the overall thromboembolic risk in ESUS patients through the composition of individual risks associated with all prevalent pathologies.

Trivial aortic valve regurgitation in children and adolescents with structurally normal hearts: physiologic or pathologic?

BACKGROUND

Trivial regurgitation from a normal aortic valve is rarely seen in healthy children and adolescents. The aim of this study was to evaluate timing of presentation, associated conditions, and medium-term prognosis of this incidental finding.

METHODS

Paediatric patients observed to have trivial aortic valve regurgitation with otherwise normal echocardiograms were retrospectively analysed. Clinical and echocardiographic parameters were measured and categorised on presentation and follow-up.

RESULTS

Sixty patients (39 males) were identified over a 13-year period. Age at presentation was 14.8 years (IQR 12.9-16.0), height z-score was + 0.71 (95% CI + 0.48- + 0.94), and body mass index z-score was + 0.66 (95% CI + 0.40- + 0.92). Median aortic regurgitation vena contracta diameter was 1.0 mm (IQR 0.8-1.3). Aortic valve strands were visualised in 28% and physiologic mitral regurgitation in 32%. Aortic annulus, sinotubular junction, and mid-ascending aorta diameters were normal, and mean aortic sinus diameter was only slightly increased (z-score + 0.23, 95% CI + 0.02- + 0.44). Follow-up data were obtained in 36 patients from 1 to 6.7 years later (median 2.1). Aortic regurgitation was no longer detectable in 28%, and none exhibited worsening. Mitral regurgitation prevalence was lower in those with aortic regurgitation resolution versus persistence (10% versus 50%, p = 0.03).

CONCLUSIONS

Trivial aortic regurgitation in paediatric patients with normal hearts is more common in adolescents and is associated with an increased prevalence of aortic valve strands and physiologic mitral regurgitation. These findings do not worsen during growth and may resolve consistent with being physiologic rather than pathologic.

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.

Stroke and Noninfective Native Valvular Disease

PURPOSE OF REVIEW

Embolic stroke of undetermined source is a challenging clinical entity. While less common than atrial fibrillation and endocarditis, many noninfective heart valve lesions have been associated with stroke and may be considered as culprits for cerebral infarcts when other more common causes are excluded. This review discusses the epidemiology, pathophysiology, and management of noninfective valvular diseases that are commonly associated with stroke.

RECENT FINDINGS

Calcific debris from degenerating aortic and mitral valves may embolize to the cerebral vasculature causing small- or large-vessel ischemia. Thrombus which may be adherent to calcified valvular structures or left-sided cardiac tumors may also embolize resulting in stroke. Tumors themselves, most commonly myxomas and papillary fibroelastomas, may fragment and travel to the cerebral vasculature. Despite this broad differential, many types of valve diseases are highly comorbid with atrial fibrillation and vascular atheromatous disease. Thus, a high index of suspicion for more common causes of stroke is needed, especially given that treatment for valvular lesions typically involves cardiac surgery whereas secondary prevention of stroke due to occult atrial fibrillation is readily accomplished with anticoagulation.

Utility of transesophageal echocardiography in the identification and treatment of occult mechanisms of cerebral infarction

Cryptogenic stroke comprises approximately 25% of all cases of ischemic stroke. The diagnostic evaluation of these patients remains a challenge in clinical practice. Transesophageal echocardiography (TEE) has been shown to have superior diagnostic accuracy in identifying potential cardioembolic sources of ischemic stroke when compared to transthoracic echocardiography (TTE). However, there has been inconsistent data on the management implications of these new cardiac findings. The addition of TEE to the comprehensive stroke evaluation will better identify potential cardiac sources of embolism (CSE) and will result in significant management changes. A prospective registry of consecutively admitted patients with acute ischemic stroke (1/1/2015-8/10/2020) was retrospectively queried. Patients 18 to 60 years of age with stroke due to mechanisms other than large or small vessel disease, or atrial fibrillation were eligible for inclusion. The primary outcome was any high-risk CSE identified on TEE following unrevealing TTE. Of the 2,404 consecutive stroke patients evaluated during the study period, 263 (11%) met inclusion criteria and the median age was 53 (IQR 46-57). TEE was performed in 108 patients (41%). A high-risk CSE was identified in 36 patients (33%), the majority of which were PFOs (n = 29). TEE led to a clinical management change in 14 patients (39%) after identification of a high-risk CSE; 6 underwent PFO closure and 8 had adjustment to their antithrombotic therapy. The addition of TEE to the comprehensive stroke evaluation led to the identification of a high-risk CSE in one in three patients resulting in significant management changes.

Neurologic complications of nonrheumatic valvular heart disease

Valvular heart disease (VHD) is frequently associated with neurologic complications. Cerebral embolism is the most common, since thrombus formation results from the abnormalities in the valvular surfaces and the anatomic and physiologic changes associated with valve dysfunction, including atrial or ventricular enlargement, intracardiac thrombi, and cardiac dysrhythmias. Prosthetic heart valves, particularly mechanical valves, are very thrombogenic, which explains the high risk of thromboembolism and the need for long-term anticoagulation. Transcatheter aortic valve replacement (TAVR) has emerged as a nonoperative alternative to surgical aortic valve replacement for patients with intermediate or high surgical risk, and the procedure also has a risk of cerebral ischemia. In addition, anticoagulation, the mainstay of treatment to prevent cerebral embolism, has known potential for hemorrhagic complications. The emergence of new oral anticoagulants with similar effectiveness to warfarin and a better safety profile has facilitated the management of patients with atrial fibrillation. However, their application in patients with mechanical heart valves is still evolving. The prevention and management of these complications requires an understanding of their natural history to balance the risks posed by valvular heart disease, as well as the risks and benefits associated with the treatment.

Lambl's excrescence in transcatheter aortic valve implantation: prevalence and risk of embolic events

BACKGROUND

The role of aortic valve Lambl's excrescence (LEs) in determining ischemic events has not been well clarified, but they can represent a potential embolic source during procedures with catheter/device manipulation through the aortic valve. Aim of our study was to assess the prevalence of LEs and the rate of embolism in patients with aortic valve stenosis scheduled for transcatheter aortic valve implantation (TAVI).

METHODS

Our population was divided into two groups, named LEs and no-LEs. In each group, the rate of cerebral embolic events was assessed, as well as other TAVI-related complications.

RESULTS

In our study population 28 patients (37%) had aortic strands and 48 (63%) did not have them. A cerebral protection device was used in four patients of LEs group (14% vs. 0, P=0.03). The mean procedural time was similar in the two groups: 50±19 and 55±26 minutes (P=0.38) in LEs and no-LEs groups, respectively. The device success was achieved in 96% of LEs and 88% of no-LEs patients (P=0.37). Two patients of no-LEs group died during the procedure. Major complications were observed in both groups without any significant differences. Only one case of stroke occurred in the population without LEs (0 LEs vs. 2% no-LEs, 0.78). No cases of peripheral embolism were observed.

CONCLUSIONS

In our population the observation of LEs is not uncommon. Despite the presumed high risk of embolism, we have not observed an increase in the rate of cerebral ischemic events or other TAVI related complications in patients with LEs.