Investig Magn Reson Imaging.  2016 Jun;20(2):132-135. 10.13104/imri.2016.20.2.132.

Paradoxical Response of Giant Left Atrial Appendage Aneurysm after Catheter Ablation of Atrial Fibrillation

• Chung JW
• Shim J
• Shim WJ
• Kim YH
• Hwang SH

• KMID: 2327427
• DOI: http://doi.org/10.13104/imri.2016.20.2.132

Abstract

We report the case of a 43-year-old male with both giant left atrial appendage (LAA) aneurysm and drug-refractory atrial fibrillation (AF). The patient was treated with percutaneous electrical isolation of cardiac arrhythmogenic substrate, and has been free of AF symptom over one year. Although the surgical resection of giant LAA aneurysm is mostly used to prevent systemic thromboembolism, we have performed follow-up of the giant LAA aneurysm using cardiac magnetic resonance (CMR) imaging and transesophageal echocardiography (TEE) after the successful catheter ablation of refractory AF. At one-year follow-up CMR, the giant LAA aneurysm showed remarkable enlargement as well as decreased contractility. Additionally, one-year follow-up TEE showed spontaneous echo contrast as an indicator of blood stasis in the giant LAA aneurysm. Those findings of giant LAA aneurysm suggest that the risk of thromboembolism may be high despite termination of AF.

Keyword

Left atrial appendage; Atrial fibrillation; Catheter ablation; Magnetic resonance imaging; Echocardiography

MeSH Terms

Adult
Aneurysm*
Atrial Appendage*
Atrial Fibrillation*
Catheter Ablation*
Catheters*
Echocardiography
Echocardiography, Transesophageal
Follow-Up Studies
Humans
Magnetic Resonance Imaging
Male
Thromboembolism

Figure

• 

  Fig. 1 Baseline cardiac magnetic resonance (CMR) and transesophageal echocardiography (TEE) of the giant left atrial appendage (LAA) aneurysm before the catheter ablation of atrial fibrillation (AF). CMR angiography (a) describes entire appearance of LAA aneurysm and left ventricle (LV). On the CMR angiography, the segmentation of LAA aneurysm (green color) allows the volume assessment of giant LAA aneurysm as 158 cm3 (b, c). On cine-CMR images (d, e), the maximum dimensions of LAA aneurysm at left ventricular systole and diastole are aneurysm shows 34.75 mm and 24.01 mm, respectively. TEE image (f) shows no thrombus and spontaneous echo contrast in the giant LAA aneurysm.

• 

  Fig. 2 One year follow-up cardiac magnetic resonance (CMR) and transesophageal echocardiography (TEE) of the giant left atrial appendage (LAA) aneurysm after catheter ablation of atrial fibrillation (AF). CMR angiography (a) describes entire appearance of LAA aneurysm covering the left ventricle. On the CMR angiography, the segmentation of LAA aneurysm (green color) provides the volume assessment of giant LAA aneurysm as 205 cm3 (b, c). On the cine-CMR images (d, e), the maximum dimensions of LAA aneurysm at left ventricular systole and diastole are aneurysm shows 46.34 mm and 42.76 mm, respectively. Furthermore, TEE image (f) shows spontaneous echo contrast related to blood stasis in the giant LAA aneurysm.

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