In total, 263 patients exhibited no contrast defect (CD) by prone-position contrast computed tomography (pCT), and catheter ablation for atrial fibrillation was subsequently performed. At that time, no intracardiac thrombus was found on intracardiac echocardiography (ICE). A CD observed only during pCT in the early phase was found in 34 patients, but not during pCT in the late one; these patients showed no thrombi due to ICE during ablation. The remaining six patients had CD in both the early and late phases of pCT. They did not undergo catheter ablation, and pCT was conducted after several months of altered or increased oral anticoagulation (OAC) therapy. Thereafter, all six patients showed no CD on pCT in the late phase, and no thrombus was observed using ICE.
Table 3. Clinical characteristics of patients with and without residual contrast medium in the left atrial appendage