THE VALUE OF SPIRAL COMPUTER-TOMOGRAPHY F OR THE DEMONSTRATION OF AORTO CORONARY BYPASSES

Spiral computer tomography (Sp-CT) was performed on 25 patients with 8 1 aorto-coronary bypasses, with persistent symptoms, following selecti ve coronary angiography. The purpose was to determine to what extent S p-CT is able to demonstrate patency or occlusion of individual bypasss es. From the raw data, transverse sections and standardised 3D reconst ructions were obtained. Statistical evaluation showed a sensitivity of 93% and a specificity of 100% with regard to patency Sp-CT provides o ptimal contrast and complete demonstration of the bypass without movem ent artifacts from respiration. 3D reconstructions aid in the evaluati on of complex anatomical situations but occasionally lead to incorrect diagnosis of stenoses or occlusions. Compared with other non-invasive procedures (conventional CT and NMR) Sp-CT has proved significantly b etter for the evaluation of bypass occlusions. Sp-CT cannot completely replace angiography but in some cases may be an acceptable alternativ e.