대한흉부영상의학회 Weekly Chest Cases

Case No : 1310 Date 2022-11-30

Courtesy of Youngjae Choi, Jeung Sook Kim / Dongguk University Ilsan hospital, Gyeonggi-do, Korea, Chung-Ang University Gwangmyeong Hospital
Age/Sex 53 / F
Chief ComplaintC.C: dyspnea and mild palpitation (2DA). PMH.: none

Figure 1
Figure 2
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Figure 4

Diagnosis With Brief Discussion

Diagnosis: Left atrial appendage aneurysm (LAAA)
Radiologic Findings: Fig1. On chest PA, heart was enlarged, the left upper cardiac border was bulging in a round shape, and the cardiac apex was uplifted
Fig2. On lateral radiography, convexity of the left atrial border is suspected, and the LUL bronchus was minimally posterior displaced.
Fig3. Axial and sagittal images of enhanced chest CT depicted diffuse enlargement of the left atrial appendage (70 mm x 54 mm x 48 mm) with no filling defect or extrinsic compression of LV and the surrounding major vessels (black arrow in axial image: left anterior descending coronary artery, white arrow in the sagittal image: cardiac vein). The size was calculated based on the longest diameter of width x depth x height of LAAA. (*: LAAA)
Fig4. 2 chamber cine MRI showed diffuse enlargement of the left atrial appendage with an intact pericardium (white arrow). It revealed slow mixing flow on real-time imaging. (*: LAAA)
Brief Review: Left atrial appendage aneurysm (LAAA) is a rare heart anomaly caused by congenital dysplasia of the pectinate muscle or by acquired pathological conditions of the mitral valve or cardiac muscle. It is associated with life threatening complications and most patients require surgical treatment.
LAAA occurs in all ages, the mean age of presentation is 31��20 years (fetus at 28 weeks to 88 years). Clinical manifestation ranges from asymptomatic to palpitation, dyspnea, and chest pain. Physical examination is normal to cardiac murmur and irregular pulse. LAAA can also be classified as intrapericardial and extrapericardial depending on the location. The intrapericardial type is caused by weakness in the wall of the left atrium and/or appendage. The extrapericardial type is associated with pericardial defect through which the appendage can herniate and progress to aneurysmal dilatation. The extrapericardial type is known to have a better prognosis.
The most common accompanying abnormalities are atrial tachyarrhythmia and the formation of thrombus. Pathophysiologically, enlargement of the atrium provides a substrate in which an electrical signal is triggered or reentrant, causing atrial tachyarrhythmia. And trabeculation of left atrial appendage wall along with improper contraction by arrhythmia leads to blood stagnation and clot forming. Moreover, when the aneurysm becomes larger, it can cause mass effects that compress the left ventricle and left coronary artery, which result in cardiac dysfunction and myocardial ischemia. If LAAA induces volume overload in LA, it leads to LA myocardial remodeling and subsequent diastolic hear failure.
The diagnostic tool is transthoracic echocardiography (TTE), enhanced chest (or cardiac) CT and enhanced cardiac MRI. On enhanced chest CT, dilated LAA can be easily diagnosed as LAAA and can be finded out accompanying complications such as intraluminal thrombus and/or compression of surrounding structures (left circumflex artery, great cardiac vein and the left phrenic nerve). On MRI, not only the cardiac function, but also the dynamic mass effect of LAAA during the cardiac cycle and degree of fibrosis can be observed.
References: 1. Wang B, Li H, Zhang L, He L, Zhang J, Liu C, et al. Congenital left atrial appendage aneurysm: A rare case report and literature review. Medicine 2018;97.
2. Aryal MR, Hakim FA, Ghimire S, Ghimire S, Giri S, Pandit A, et al. Left atrial appendage aneurysm: a systematic review of 82 cases. Echocardiography 2014;31:1312-1318.
3. Naksuk N, Padmanabhan D, Yogeswaran V, Asirvatham SJ. Left atrial appendage: embryology, anatomy, physiology, arrhythmia and therapeutic intervention. JACC: Clinical Electrophysiology 2016;2:403-412.
4. Nathan, Mewton, et al., Assessment of myocardial fibrosis with cardiac magnetic resonance. Journal of the American college of cardiology 57.8 (2011): 891.
Keywords: Left atrial appendage aneurysm,

No. of Applicants : 86

▶ Correct Answer : 63/86, 73.3%

- Saitama-Sekishinkai Hosptal , Japan MIHOKO YAMAZAKI
- , Japan KYOKO NAGAI
- Showa General Hospital , Japan MASAFUMI KAIUME
- Ulsan University Hospital , Korea (South) SOYEOUN LIM
- McGill University Health Center , Canada ALEXANDRE SEMIONOV
- CHCB , France LE GUEN RAPHAEL
- Kyoto City Hospital , Japan YUSUKE UTSUNOMIYA
- , Italy PAOLO BALDASSARI
- Tiger Gate Hospital , Japan SHIN-ICHI CHO
- Chungbuk National University Hospital , Korea (South) JIYUN KANG
- Vita Hospital , Brazil DIOGO LAGO PINHEIRO
- Other , Korea (South) SEONGSU KANG
- Scans world , India PHILSON JOSEPH MUKKADA
- , Korea (South) JIN YOUNG LEE
- Oita University, Faculty of Medicine , Japan FUMITO OKADA
- Seoul Medical Center , Korea (South) HYUK GI HONG
- Samsung Medical Center , Korea (South) JUHYUN KIM
- Osaka University , Japan AKINORI HATA
- , Japan HIKARI FUKUI
- Ajou University Hospital , Korea (South) HAEIN LEE
- Osaka Metropolitan University , Japan HIROTAKA TAKITA
- Shimada General Medical Center , Japan HAYATO NOZAWA
- Ajou University Hospital , Korea (South) HYUNSEUNG LEE
- The University of Tokyo Hospital , Japan TOSHIHIRO FURUTA
- Narayana Multispeciality Hospital Jaipur Rajasthan , India JAINENDRA JAIN
- Ajou University Hospital , Korea (South) JAYOUNG MOON
- Gifu University Hospital , Japan Yo Kaneko
- Hukuda memorial hospital , Japan SHINTARO KANO
- , Korea (South) HYOUNG YEOB KIM
- , Japan KENTARO KOTANI
- Kyoto University Hospital , Japan YASUHISA KURATA
- Other , Korea (South) CHAEHUN LIM
- Other , Korea (South) MARI A
- Osaka Metropolitan University Hospital , Japan SHU MATSUSHITA
- Chungbuk National University Hospital , Korea (South) MIHYEON PARK
- Jichi Medical University, School of Medicine , Japan MITSURU MATSUKI
- University of Tsukuba, Dept of Radiology , Japan MANABU MINAMI
- Centre Hospitalier Regional de Lanaudiere , Canada MATTHIEU STORME
- Avrasya Hospital/ISTANBUL , Turkey MURAT ULUSOY
- , Qatar NABIL SHERIF MAHMOOD
- , United Arab Emirates NEHAR RANJAN CHAKRABORTY
- Dokkyo Medical University , Japan HIROAKI ARAKAWA
- Chonnam National University Hwasun Hospital , Korea (South) JEONG YEOP LEE
- Holy Family Hospital , India RAJESH GOTHI
- Ulsan University Hospital , Korea (South) SUNGMIN KIM
- Mie University Hospital , Japan KENSUKE DOMAE
- , Japan MATSUNO MAI
- Kyoto University Hospital , Japan SATOSHI IKEDA
- Pusan National University Yangsan Hospital , Korea (South) JI HWAN KIM
- Yonsei University,Severance Hospital , Korea (South) SEO BUM CHO
- Toranomon Hospital , Japan KAORU SUMIDA
- Ichinomiya Nishi Hospital , Japan Takao Kiguchi
- Nerimahikarigaoka hospital , Japan TAKANA HAYASHI
- The University of Tokyo Hospital , Japan HIROSHI TAKUMIDA
- Matsunami General Hospital , Japan TARO TAKEDA
- Gyeongsang National University Hospital , Korea (South) BYEONG JU KOO
- , Japan YUMI MAEHARA
- , Japan NOBUYUKI OTANI
- , Japan YUKI HAYASHI
- Diagnose.me (BV) / Royal Perth Hospital , Australia YURANGA WEERAKKODY
- , Korea (South) HM PARK
- the first affiliatited hospital of nanjing medical univercity , China HAI XU
- Jiangsu province hospital , China WANGJIAN ZHA

▶ Correct Answer as Differential Diagnosis : 4/86, 4.7%

- Jichi Medical University Hospital , Japan JUN KANZAWA
- Soonchunhyang University Hospital Bucheon , Korea (South) HYEJOO PARK
- Seoul National University Bundang Hospital , Korea (South) YOONAH DO
- The Catholic University of Korea Yoeuido St. Mary , Korea (South) CHAWOONG JEON

▶ Semi-Correct Answer : 3/86, 3.5%

- Chonbuk National University Hospital , Korea (South) JUNGHWAN KIM
- Osaka metropolitan university Hospital , Japan TATSUSHI OURA
- Other , Korea (South) SEONG WON JANG

대한흉부영상의학회 Korean Society of Thoracic Radiology

Cases by Disease Category

Case No : 1310 Date 2022-11-30

Discussion

No. of Applicants : 86