Use of transoesophageal echocardiography to detect and manage atrial thrombi in light-chain cardiac amyloidosis: a case report

Abstract

Background: Increased intracardiac thrombus formation in light-chain cardiac amyloidosis (AL-CA) has been associated with thrombotic events such as stroke and high rates of mortality and morbidity.

Case summary: A 51-year-old man was admitted to the emergency department with a sudden change in consciousness. His emergency brain magnetic resonance imaging showed two foci of cerebral infarction on the bilateral temporal lobes. His electrocardiogram displayed a normal sinus rhythm with low QRS voltage. Transthoracic echocardiography showed concentric thickened ventricles, dilatation of both atria, a left ventricular ejection fraction of 53%, and a Grade 3 diastolic dysfunction. The bull-eye plot on speckle tracking echocardiography displayed a distinctive apical sparing pattern. A serum-free immunoglobulin analysis showed increased lambda-free light chains (295.59 mg/L) with a reduced kappa/lambda ratio (0.08). Light-chain amyloidosis was subsequently confirmed by examining the histology of the abdominal fat-pad tissue. On transoesophageal echocardiography (TEE), an elongated static thrombus and a mobile bouncing oval thrombus were found on the left and right atrial appendages, respectively. Atrial thrombi were managed with a full dose of dabigatran of 150 mg twice daily, which resulted in a complete resolution after 2 months of TEE follow-up.

Discussion: Complicating intracardiac thrombosis has been considered one of the major contributions of death in cardiac amyloidosis. Transoesophageal echocardiography should be established to aid in the detection and management of atrial thrombus in AL-CA.

Keywords: Cardiac amyloidosis; Case report; Light chain; Thrombus; Transoesophageal echocardiography.

Figure 1

Brain magnetic resonance imaging showed two foci of cerebral infarctions in bilateral temporal lobes (A), cerebrovascular magnetic resonance imaging suggested the occlusion of the M3 branches (B), and 12-lead electrocardiogram indicated a sinus rhythm with some premature atrial beats and low QRS voltages on the limb leads (C).

Figure 2

Transthoracic echocardiography showed hypertrophic ventricles and enlarged atria on four-chamber view (A), an abnormally high E/A wave ratio of 3.11 on Doppler imaging (B), ‘apical sparing’ pattern (C), and reduced left atrial strain parameters (D) on speckle tracking echocardiography.

Figure 3

Abdominal fat-pad biopsy result was positive for Congo red staining (A), under polarized light (B), and for lambda light chain with immunofluorescence staining (C).

Figure 4

Thrombi (white arrows) with the presence of spontaneous contrast in the left (A1) and right (B1) atrial appendages on mid-oesophageal two-chamber view (80–90°) and mid-oesophageal bicaval view, respectively. Resolution of thrombi (asterisks) in the left (A2) and right (B2) atrial appendages after 2 months of anticoagulation therapy.