Myocardial Late Iodine Enhancement Using Photon-Counting Computed Tomography in Patients With Hypertrophic Cardiomyopathy

A 79-year-old man with hypertrophic cardiomyopathy was admitted to the Okayama University Hospital for catheter ablation of paroxysmal atrial fibrillation. Photon-counting detector computed tomography (PCD-CT) was performed as part of the preprocedural workup. All scans were acquired using a PCD-CT (NAEOTOM Alpha; Siemens Healthcare GmbH, Forchheim, Germany). The CT imaging protocol is shown in Figure A and described in the Supplementary Methods. Immediately after coronary CT angiography, 50 mL iodinated contrast medium was injected. A delayed-phase CT scan was performed 6 min after contrast agent injection. No significant coronary artery stenosis was noted (Figure B). Late scans showed late iodine enhancement at the base of the ventricular septum on PCD-CT (Figure C; Supplementary Figures 1,2). The patient had undergone cardiac magnetic resonance imaging (CMR) 3 years ago, which was consistent with the area of late iodine enhancement on PCD-CT (Figure D).

Figure.

(A) Computed tomography (CT) imaging protocol. (B) Coronary CT angiography. LAD, left anterior descending artery; LCX, left circumflex artery; RCA, right coronary artery. (C) Late iodine enhancement (LIE) on delayed-phase CT (iodine map). Linear contrast enhancement at the base of the ventricular septum. (D) Late gadolinium enhancement on delayed-phase CMR was consistent with the site of LIE on delayed-phase CT.

PCD-CT, a new detector technology, is based on the direct conversion of X-ray photons into electrical signals by semiconductors.¹ PCD-CT provides high-quality images by offering intrinsic spectral capabilities, increased spatial resolution, reduced electronic noise, and improved image contrast. This case suggests that PCD-CT may have diagnostic performance equivalent to that of CMR in the diagnosis of myocardial disease. PCD-CT is expected to become increasingly important in the diagnosis of cardiac lesions.

Disclosure

K.N., H.I. are members of Circulation Reports’ Editorial Team.

Supplementary Files

Please find supplementary file(s);

https://doi.org/10.1253/circrep.CR-23-0034

Reference

• 1.   Willemink MJ, Persson M, Pourmorteza A, Pelc NJ, Fleischmann D. Photon-counting CT: Technical principles and clinical prospects. Radiology 2018; 289: 293–312.