Added value of cardiac computed tomography for evaluation of mechanical aortic valve: Emphasis on evaluation of pannus with surgical findings as standard reference.
BACKGROUND
The added value of cardiac computed tomography (CT) with transesophageal echocardiography (TEE) for evaluating mechanical aortic valve (AV) dysfunction has not yet been investigated. The purposes of this study were to investigate the added value of cardiac CT for evaluation of mechanical AVs and diagnoses of pannus compared to TEE, with surgical findings of redo-aortic valve replacement (AVR) used as a standard reference.


METHODS
25 patients who underwent redo-AVR due to mechanical AV dysfunction and cardiac CT before redo-AVR were included. The presence of pannus, encroachment ratio by pannus, and limitation of motion (LOM) were evaluated on CT. The diagnostic performance of pannus detection was compared using TEE, CT, and CT+TEE, with surgical findings as a standard reference. The added value of CT for diagnosing the cause of mechanical AV dysfunction was assessed compared to TTE+TEE.


RESULTS
In two patients, CT analysis was not feasible due to severe metallic artifacts. On CT, pannus and LOM were found in 100% (23/23) and 60.9% (14/23). TEE identified pannus in 48.0% of patients (12/25). CT, TEE, and CT+TEE correctly identified pannus with sensitivity of 92.0%, 48.0%, and 92.0%, respectively (P=0.002 for CT vs. TEE). In 11 of 13 cases (84.6%) with inconclusive or negative TEE results for pannus, CT detected the pannus. Among 13 inconclusive cases of TTE+TEE for the cause of mechanical AV dysfunction, CT suggested 6 prosthetic valve obstruction (PVO) by pannus, 4 low-flow low-gradient PVO, and one LOM without significant PVO.


CONCLUSIONS
Cardiac CT showed added diagnostic value with TEE in the detection of pannus as the cause of mechanical AV dysfunction.
Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Republic of Korea.
Young Joo
YJ
Suh
Department of Cardiovascular Surgery, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Republic of Korea.
Sak
S
Lee
Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Republic of Korea.
Dong Jin
DJ
Im
Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Republic of Korea.
Suyon
S
Chang
Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Republic of Korea.
Yoo Jin
YJ
Hong
Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Republic of Korea.
Hye-Jeong
HJ
Lee
Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Republic of Korea.
Jin
J
Hur
Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Republic of Korea.
Byoung Wook
BW
Choi
Department of Cardiovascular Surgery, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Republic of Korea.
Byung-Chul
BC
Chang
Department of Cardiology, Severance Cardioivascular Hospital, Yonsei University College of Medicine, Republic of Korea.
Chi Young
CY
Shim
Department of Cardiology, Severance Cardioivascular Hospital, Yonsei University College of Medicine, Republic of Korea. Electronic address: grhong@yuhs.ac.
Geu-Ru
GR
Hong
Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Republic of Korea. Electronic address: dryj@yuhs.ac.
Young Jin
YJ
Kim
D000328:Adult; D001021:Aortic Valve / Q000000981:diagnostic imaging* / Q000601:surgery; D017548:Echocardiography, Transesophageal; D005260:Female; D006349:Heart Valve Diseases / Q000000981:diagnostic imaging* / Q000601:surgery; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D012086:Reoperation; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
Aortic valve replacement; Computed tomography; Mechanical valve; Pannus formation