Abstract
BACKGROUND: Recent studies have demonstrated that delayed enhancement using contrast-enhanced computed tomography corresponds with late gadolinium enhancement on cardiac magnetic resonance imaging. However, few studies have evaluated scar-related ventricular tachycardia (VT) substrates using high-resolution photon-counting detector computed tomography (PCD-CT). CASE SUMMARY: A 49-year-old man with cardiac sarcoidosis underwent catheter ablation of monomorphic VT. Preoperative iodine mapping on PCD-CT showed late iodine enhancement (LIE) localized to the septal region between the periaortic region and right ventricular outflow tract. Electroanatomic mapping revealed a localized abnormal voltage area and line of conduction block with split potentials colocalized with the LIE. Radiofrequency ablation was performed from both the right and left ventricular outflow tracts and successfully eliminated the VT inducibility. No ICD shocks have occurred after the procedure. DISCUSSION: PCD-CT provides improved signal detection and superior spatial resolution, enabling visualization of VT substrates in anatomically challenging regions. In patients who are contraindicated for cardiac magnetic resonance imaging, PCD-CT serves as a valuable alternative imaging modality.