Lambl's Excrescences: Association with Cerebrovascular Disease and Pathogenesis

Abstract

Background: Lambl's excrescences (LEx) are detected by transesophageal echocardiography (TEE) and are characterized as thin, elongated, and hypermobile structures located at the leaflets' coaptation point of the heart valves. The association of LEx with cerebrovascular disease (CVD) is still undefined and yet patients with LEx and suspected CVD receive unproven effective antiplatelet or anticoagulant therapy or even undergo valve surgery. Also, the association of LEx with aging and atherogenic, inflammatory, or thrombogenic parameters has not been reported. Methods: Seventy-seven patients with systemic lupus erythematosus (SLE) (71 women, age 37 ± 12 years) and 26 age- and sex-matched healthy controls (22 women, age 34 ± 11 years) prospectively underwent routine history and physical exam, transcranial Doppler, brain MRI, TEE, carotid duplex, and clinical and laboratory evaluations of atherogenesis, inflammation, platelet activity, coagulation, and fibrinolysis. Subjects without stroke/TIA on enrollment (with and without LEx) had a median follow-up of 57 months. Results: On enrollment, 33 (43%) of 77 patients had CVD manifested as acute stroke/TIA (23 patients), cerebromicroembolism by transcranial Doppler (17 patients), or cerebral infarcts by MRI (14 patients). Mitral or aortic valve LEx were equally frequent in healthy controls (46%) as in patients with and without any CVD (39 and 43%), stroke/TIA (35 and 43%), cerebromicroembolism (41 and 42%), or cerebral infarcts (36 and 43%) (all p ≥ 0.72). Also, other mechanisms for CVD other than LEx such as Libman-Sacks vegetations, patent foramen ovale or interatrial septal aneurysm, aortic or carotid atherosclerosis, or thrombogenesis were found in ≥94% of patients with CVD. In addition, 36 subjects with and 44 without LEx had similar low incidence of stroke/TIA (1 (1.3%) and 2 (2.5%), respectively, p = 1.0) during follow-up. Finally, LEx were not associated with aging, atherogenic risk factors, atherosclerosis, inflammation, or thrombogenesis. Conclusions: In this study, LEx are similarly prevalent in healthy controls and SLE patients, are not associated with CVD, and are not associated with pathogenic risk factors. Therefore, the study findings suggest that LEx may not be cardioembolic substrates, may not represent pathologic valve structures, and may not require therapy.

Lambl’s Excrescences in Congenital Heart Disease and Other Clinical Situations: A Series of 17 Cases

“…AV dysfunction does not seem to influence the development of LEx but the morphological changes associated with AV dysfunction can foster non-ex LEx. 12 In the adult, the embolic risk of valvular LEx was evaluated by Roldan et al 13 in a prospective study published in 2015; this study involved 90 healthy subjects and 88 patients with or without suspected cardioembolism and followed the cases clinically for approximately 4 years. The prevalence of LEx in healthy subjects (38%) and in patients with (47%) or without (41%) suspected cardioembolism was similar, irrespective of age or sex, and the presence of LEx did not appear to be associated with future embolic events.…”

“…These findings suggested that there may not be a direct causal link between ischemic stroke and the presence of the valve strands. 13 A review of the current literature shows many different views on the clinical importance, pathophysiology, association with ischemic events and management of LEx. However, there is a general consensus amongst most of the authors that LEx should be considered in the differential diagnosis of patients who present with signs of cardioembolism, until conclusive evidence suggests otherwise.…”

Acute Myocardial Infarction in a Patient with Two-Vessel Occlusion and a Large Lambl’s Excrescence

“…Nevertheless, the embolic risk could not be directly related to LE's length, as we can read in Aziz and Baciewicz's report about a woman with repeated strokes and thin LE (1–4 mm long) on all the 3 leaflets of the aortic valve [23]. In a recent study focused on patients with Systemic Lupus Erythematosus Roldan and colleges reported that the LE's length was similar in patients with (11.9 ± 4.9 mm) and without (11.7 ± 3.5 mm) cerebrovascular disease and in controls (9.1 ± 3.4 mm) [24]. …”

Diagnosis and Treatment of Lambl’s Excrescence on the Aortic Valve

“…Asymptomatic patients should be monitored closely. Some believe that perhaps these filaments are simply "innocent bystanders" of no pathophysiologic significance, based on the fact that there may not be a direct causal link between ischemic stroke and the presence of the valve strands [Roldan 2015;Melduni 2008;Cohen 1997]. Therefore, it is recognized that there may be occasional exceptions, especially when large lesions with a head or a stalk are found [Melduni 2008].…”