ECG-gated multidetector computed tomography for the assessment of the postoperative ascending aorta

This study was undertaken to define the role of electrocardiographically (ECG)-gated multidetector computed tomography (MDCT) in the assessment of the postoperative ascending aorta.

From November 2006 to June 2007, 21 patients, [11 men, ten women; age +/- standard deviation (SD): 62.7+/-10.8 years] with a history of ascending aorta replacement underwent ECG-gated MDCT and were prospectively included in our study. Ascending aorta replacement had been performed with different surgical techniques: Bentall-De Bono (four patients, 19%), Tirone-David (five patients, 23%), and modified Tirone-David with creation of aortic neosinuses (12 patients, 57%). Two patients were excluded from MDCT evaluation because they failed to fulfil the inclusion criteria. Transthoracic echocardiography was used as the reference standard. All patients provided informed consent.

In all patients, ECG-gated MDCT provided a clear depiction of the aortic annulus, aortic root and ascending aorta, enabling accurate measurements in all cases. The aortic valve area (3.4+/-0.2 cm(2)), the diameter of the sinotubular junction (31.6+/-1.8 mm), the diameter of the neosinuses in the case of modified Tirone-David procedures (37.3+/-2.1 mm) and the distance between the cusps and the graft wall during systole (3.1+/-0.7 mm) fell within standard ranges and showed a good correlation (r=0.89) with the values obtained with transthoracic echocardiography.

MDCT is currently considered a compulsory diagnostic step in patients with suspected or known aortic pathology. MDCT is a reliable technique for anatomical and functional assessment of the postoperative aortic root and provides cardiac surgeons with new and detailed information, enabling them to formulate a prognostic opinion regarding the outcome of the surgical procedure.