ABSTRACT
AIMS: Introduction of a novel contrast injection protocol during rotational C-arm CT (RCT) in cardiac catheterisation of patients with aortic stenosis for aortic root assessment. METHODS AND RESULTS: Fifty-two patients underwent RCT imaging with contrast injection performed either into the aorta (Ao-RCT, n=25) or into the left ventricle (LV-RCT, n=27). Aortic annulus diameters were assessed in a multiplanar reconstruction view and compared with corresponding multidetector computed tomography (MDCT). LV contrast injection additionally enabled measurement of the left ventricular outflow tract (LVOT). LV-RCT improved the accuracy of annulus measurements and correlated well with MDCT data in comparison with Ao-RCT and MDCT (r=0.91, r=0.76, respectively). The Bland-Altman analysis showed smaller differences in MDCT and LV-RCT annulus measurements than between MDCT and Ao-RCT (LV-RCT: mean=0.4 mm, limits of agreement -1.5-2.3 mm vs. Ao-RCT: mean=0.1 mm, limits of agreement -3.4-3.6 mm). The inter-observer agreement for the annulus measurements was significantly increased for LV-RCT as calculated by the intra-class coefficient (ICC=0.85) in comparison with Ao-RCT (ICC=0.52). CONCLUSIONS: Cardiac catheterisation including LV-RCT offers complementary assessment of left ventricular function, aortic valve anatomy, coronary angiography and arterial access routes. LV-RCT for aortic root measurements shows better correlation to MDCT than standard Ao-RCT protocols.
