Makoto Amanuma MD, Presenter: Nothing to Disclose

Takeshi Kondo, Abstract Co-Author: Nothing to Disclose

Tomoya Takayanagi, Abstract Co-Author: Nothing to Disclose

Takako Sekine, Abstract Co-Author: Nothing to Disclose

Tomonari Sano, Abstract Co-Author: Nothing to Disclose

Shinichi Takase, Abstract Co-Author: Nothing to Disclose

To assess the clinical usefulness of subtraction coronary CT angiography (CCTA) for evaluating restenosis of metallic coronary artery stents.

This study was approved by our clinical review board, and written informed consent was obtained from all subjects. All examinations were performed using a 320-detector row MDCT scanner (Aquilion ONE ViSION Edition, Toshiba; 0.275 sec/rot.). Patients with a history of PCI, HR < 61, and breath-hold ability > 25 sec were selected as candidates for this study. Two sets of 3D volume data were obtained during a single breath-hold before and after the arrival of contrast medium in the left heart system. Data were acquired by prospective one-beat scan in the mid-diastolic phase. Volume adjustment and subtraction were performed using dedicated software. After 2 patients with motion artifacts were excluded, 66 patients (age: 73.6±8.25 years, M/F=49/17) with a total of 173 stents were included in the final evaluation. Luminal stenosis (>50% vs. ≤50%) was evaluated by three experienced observers, with catheter angiography used as the reference standard. Based on the observed changes, subtraction was judged to be effective or non-effective.

The number of non-assessable stents was 56 before subtraction and 4 after subtraction. When non-assessable lesions were counted as positive stenosis, the segment base sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 81.8%, 60.9%, 23.4%, 95.8%, and 63.6% before subtraction and 54.5%, 93.4%, 54.5%, 93.4%, and 88.4% after subtraction, respectively. Based on comparison of the effective group (N=49) and the non-effective group (N=124), the stent diameter was found to have the greatest influence, with subtraction judged to be most effective for the evaluation of 2.5-mm-diameter stents as compared with larger ones.

Subtraction CCTA was found to provide better visualization of the arterial lumen within metallic stents as well as superior diagnostic capabilities for evaluating in-stent restenosis. Patients with 2.5-mm-diameter stents can be considered to be good candidates for CCTA using this technique.

Subtraction coronary CT angiography can improve diagnostic capability of coronary artery resetnosis within the metallic stents.

Amanuma, M, Kondo, T, Takayanagi, T, Sekine, T, Sano, T, Takase, S, Clinical Usefulness of Subtraction Coronary CT Angiography for Evaluating Restenosis of Metallic Coronary Artery Stents.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14011572.html