Early Coronary Atherosclerotic Morphology in Pseudoxanthoma Elasticum: Images From Intravascular Ultrasound and Optical Coherence Tomography

Background: Pseudoxanthoma elasticum (PXE) is an inherited systemic disease of connective tissue primarily affecting the skin, retina, and cardiovascular system. It is characterized pathologically by fragmentation and calcification of elastic fiber. However, few data exist regarding the pathogenesis of the coronary atherosclerosis due to the rarity of this disease. The aim of the present study was to assess the early atherosclerotic morphology in PXE using intravascular ultrasound (IVUS) and optical coherence tomography (OCT). Methods: We assessed detailed morphological changes of the coronary arterial wall by IVUS and OCT of the two PXE cases (73 yr male and 69 yr female), both of whom were without any evidence of coronary risk factor. Distal portion of the left anterior descending artery, that was not evident of plaques by angiography, was evaluated using commercially available IVUS system and OCT system. Results: Using IVUS modality, an additional high-gain layer without acoustic shadow, which was located in the intima-media complex, was detected. This additional layer represented several tissue characteristics including fibrosis, dense fibrosis, and calcification using integrated backscatter-IVUS. The OCT image revealed this abnormal layer as heterogeneous shaggy intima without thickness, suggesting the presence of calcified fragmented internal elastic lamina. Conclusions: We report the first IVUS and OCT findings in the coronary artery in patients with PXE. These images suggest that the unique morphology found in those subjects represent a preclinical, early stage of coronary atherosclerosis in PXE.