Combined Coronary CT Angiography and Evaluation of Access Vessels for TAVR Patients in Free-Breathing with Single Contrast Medium Injection Using a 16-cm-Wide Detector CT

Abstract

To investigate the feasibility of combining coronary computed tomography (CT) angiography (CCTA) and CTA to evaluate access vessels for transcatheter aortic valve replacement (TAVR) patients in free-breathing and with single contrast medium injection using a 16-cm-wide detector CT. One hundred and twenty-one consecutive patients (73.33 ± 6.43 years) referred for TAVR underwent a serious CT scans in free-breathing after one contrast injection: ECG-triggered one-heartbeat axial CCTA, followed by non-ECG-gated neck, thoracic, and abdominal CTA. Patient weight-dependent contrast dose volume at 1.0 mL/kg was used. CT attenuation values of the coronary, neck, aortic, iliac, and femoral arteries were measured and their image quality was evaluated with a 4-point score method. Stenosis (≥50%) in CCTA was evaluated using invasive coronary angiography result as a reference standard. Radiation and contrast doses were assessed. The total dose-length-product for the entire examination was 411.4 ± 91.2 mGy.cm, and the total contrast dose was 57.3 ± 9.9 mL. There were adequate attenuations (>400 HU) in all arteries, and the peripheral access vessels and aortic annulus were evaluable in all patients. In neck CTA, 5 patients had vascular tortuosity, 6 patients had aberrant arteries and there were 212 plaques and 13 severe stenoses among the patients. In CCTA, on the per-segment, per-vessel, and per-patient analysis, CCTA showed a sensitivity and negative predictive value of (95% and 99%), (95% and 99%), and (96% and 98%), respectively, for the entire patient cohort, and (92% and 98%), (92% and 98%), and (88% and 93%), respectively, for patients with atrial fibrillation or heart rate higher than 75 beats. It is feasible to perform a combined CCTA and CTA for evaluating access vessels for TAVR patients in free-breathing with single contrast injection. This approach generates acceptable image quality for all vessels and a high negative predictive value in excluding coronary artery disease with relatively low radiation and contrast doses.