A 39-year-old man was taken to our hospital due to CPA. He had suddenly complained of breathing difficulties and chest pain half an hour earlier, then quickly had a CPA. After arrival, we achieved successful resuscitation. A chest X-ray revealed severe lung congestion. TTE showed normal left ventricular function and end-diastolic diameter (45 mm), but severe aortic regurgitation and premature mitral valve closure were present. He did not have a history of Marfan syndrome, bicuspid valve or heart murmur. We suspected that the cause of heart failure and CPA was acute aortic regurgitation resulting from AAD, based on symptoms, history and TTE findings. However, because we could not detect the dissection flap with TTE, CE-CT was performed. CE-CT did not show the flap within the aorta ( Fig. 1 ), so TEE was performed and revealed the localized dissection flap displacing the aortic valve during ventricular diastole within the ascending aorta, which was normal in diameter (35 mm) ( Fig. 2 ). In this case, only TEE could identify the localized dissection flap. The patient was not scheduled to undergo surgery because of hypoxic brain damage.
