Thromboembolic Risk in Sinus Rhythm: A New Paradigm in Light Chain Cardiac Amyloidosis

Abstract

Thromboembolic risk is increased in cardiac amyloidosis, and this goes beyond the occurrence of atrial fibrillation in these patients. A 56-year-old man was admitted to our hospital for a presyncopal episode. Clinical and instrumental findings led to a diagnosis of light chain cardiac amyloidosis. Hospitalization was complicated by ischemic stroke resulting from embolization of a left atrial thrombus, that occurred in sinus rhythm. This case highlights the importance of a new diagnostic strategy for thromboembolic risk stratification in patients with cardiac amyloidosis. Left atrial strain assessment should be implemented in patients with cardiac amyloidosis to predict the occurrence of thromboembolic events.

Keywords: anticoagulation; atrial fibrillation; atrial strain; cardiac amyloidosis; stroke; thromboembolic risk.

Graphical abstract

Visual Summary

A 56-Year-Old Patient With Undiagnosed Light Chain Cardiac Amyloidosis, With Reduced Atrial Strain Parameters, Developed a Cardioembolic Ischemic Stroke in Sinus Rhythm (A) Reduction in GLS and relative apical sparing at left ventricular strain analysis. (B) Evidence of reduced reservoir, conduit and pump atrial function using atrial strain analysis. (C) Interstitial amyloid deposits with bright positivity for anti-AL-K in an histological sample of subcutaneous periumbilical fat. (D) Right auricle thrombus (red arrows) on chest CT.

Figure 1

Macroglossia This picture taken during physical examination shows evident macroglossia, pathognomonic for light chain systemic amyloidosis.

Figure 2

Electrocardiogram on Admission The electrocardiogram shows sinus tachycardia with pseudoinfarct pattern in precordial leads, repolarization abnormalities in inferolateral leads, and low voltages in the peripheral lead.

Figure 3

Speckle Tracking Analysis (A) Left ventricular strain analysis showing reduction in GLS and relative apical sparing; (B) atrial strain analysis showing reduction in reservoir, conduit, and pump atrial function.

Figure 4

Brain Computed Tomography and Cerebral Angiography Brain computed tomography scan showing total occlusion of middle cerebral artery at the M2 level (A) and incomplete filling of the cerebral artery after contrast injection at angiography. B shows an incomplete filling of the cerebral artery after contrast injection at angiography (red arrow). The arrow in A shows a total occlusion of the middle cerebral artery at the M2 level; the arrow in B shows an incomplete filling of the cerebral artery after contrast injection at angiography.

Figure 5

Subcutaneous Abdominal Fat Aspiration Histologic evidence of interstitial amyloid deposition with bright positivity for anti-AL-K in subcutaneous periumbilical fat. TTR = transthyretin.

Figure 6

Atrial Thrombus on Chest Computed Tomography Chest computed tomography scan showing an intracavitary thrombus at the level of the right auricle. The arrows indicate the thrombus inside the right auricle.