左心房壁厚および心外膜脂肪組織のフォトカウントCTベースのマッピングを利用した心房細動ラインのシミュレーション

Creating durable linear lesions in the left atrium (LA) is the prerequisite for successful catheter ablation of peri-mitral flutter.

Using photon-counting computer tomography (PCCT), we compared patterns of myocardial thickness (MT), epicardial adipose tissue (EAT) and length of commonly used LA lines to determine the most favorable line profile for catheter ablation.

198 patients were prospectively included. PCCT of the LA was performed in all patients. After semiautomated 3D-segmentation of PCCT data, five ablation lines were simulated using specialized imaging software. These included an anteroseptal (AS), anteromedial (AM) and anterolateral line (AL) as well as superior (MIS) and inferior mitral isthmus line (MII). MT, EAT and line length were analyzed.

The data set included 115763 data points along 990 simulated lines in 198 patients. Line length was shortest in MII, longest in AM. AS showed the lowest average MT values. MT interpatient variability was greatest along the MIS. EAT was distributed inhomogenously at the anterior wall with thicker layers in medial and especially lateral aspects and highest EAT levels along the AL line. When combining MT, EAT and line length in a weighted score, AS and MII lines demonstrated the most favorable profiles for catheter ablation.

PCCT/3D-segmentation as a tool to visualize MT and EAT is very helpful to determine the most favorable line for catheter ablation of peri-mitral flutter. In a weighted score incorporating MT, EAT and line length, AS and MII lines showed promising profiles for the creation of durable linear lesions.