RESUMEN
A 26-year-old woman of Cap Verdean origin was admitted to emergency unit with chest pain and dyspnea. Because of sinus tachycardia without any other electrocardiogram abnormalities, high NT-pro BNP level, and weakly positive cardiac troponin I and D-dimer levels, an aortic and pulmonary non ECG-gated CT-angiography was performed that excluded pulmonary embolism and aortic dissection. Transthoracic echocardiography (TTE) showed a contained rupture of the non-coronary sinus of Valsalva aneurysm sized 23 to 24mm into the right atrium. According to the high rupture risk, patient had been immediately transferred in a cardiologic surgical center where transesophageal echocardiography (TEE) and thoracic angiography ECG-gated Multiple Detector Computerized Tomography (ECG-gated MDCT) reinforced the diagnosis. Patient underwent surgical repair resection of the aneurysmal sac, which was described as "tissue paper thin" and at risk for impending rupture, without evidence of communication between the aorta and the right atrium. Anatomopathological examination described a thick sclerotic and oedematous aneurysm wall without inflammation, and bacteriological examination was negative. It is a rare case of contained rupture of the congenital non-coronary sinus of Valsalva aneurysm into the right atrium (Type IV of Sakakibara classification), with a high rupture risk. This case shows that the use ECG-gated-MDCT is more appropriate when aortic dissection is suspected, allowing a detailed analysis of aorta, especially the proximal portion which is more susceptible to motion artifacts.