Free-breathing coronary CT angiography using 16-cm wide-detector for challenging patients: comparison with invasive coronary angiography

Abstract

To investigate the superiority of free-breathing coronary computed tomography angiography (CCTA) with 16-cm wide-detector CT for challenging patients who cannot hold their breath. A total of 76 patients (62% with either heart rate >75 beats/min or arrhythmia) who were unable to breath-hold underwent both free-breathing CCTA and invasive coronary angiography (ICA) were included. Two reviewers evaluated coronary arteries on a per-segment, per-vessel, and per-patient basis for image quality using a four-point scale and stenosis degree. CCTA results were compared with ICA to calculate the diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Out of 1,368 segments, 228 (16.7%) were <1.5 mm in diameter and were excluded. Thirty-two (2.3%) with calcification and 26 (1.9%) with motion artefacts were considered positive at CT. One thousand and eighty-two segments (79.1%) were evaluated both on CCTA and ICA, and 128 (11.8%) segments had ≥50% stenosis on ICA. The diagnostic accuracy, sensitivity, specificity, PPV, and NPV of CCTA were 90.8%, 88.3%, 91.1%, 57.1%, and 98.3% on a per-segment basis; 93.4%, 90.6%, 94.2%, 80.5% and 97.4% on a per-vessel basis; and 92.1%, 100%, 85%, 85.7% and 100% on a per-patient basis. For patients with high heart rates or arrhythmia, 81% (versus 79.1%) segments were evaluable, and the accuracy, sensitivity, specificity, PPV, and NPV were statistically the same as the entire study population. Free-breathing CCTA using 16-cm wide-detector CT has high accuracy compared to ICA for detecting coronary artery stenosis for challenging patients.