Comparison Between Cardiac Allograft Vasculopathy and Native Coronary Atherosclerosis by Optical Coherence Tomography

Area of Science:

• Cardiology
• Transplantation Immunology
• Medical Imaging

Background:

• Cardiac allograft vasculopathy (CAV) is a major cause of late graft loss after heart transplantation.
• Distinguishing CAV from native coronary atherosclerosis (NCA) is crucial for appropriate management.
• Intravascular imaging, particularly optical coherence tomography (OCT), offers high-resolution insights into coronary artery morphology.

Purpose of the Study:

• To compare the distribution and morphology of coronary lesions between heart transplant (HT) recipients with and without significant rejection and patients with NCA.
• To evaluate the utility of OCT in differentiating CAV from NCA.

Main Methods:

• OCT imaging was performed on the left anterior descending artery in 17 HT recipients with high-grade rejection (HGR), 43 HT recipients with low-grade rejection (LGR), and 60 patients with NCA.
• Quantitative analysis of intima area, external elastic lamina area, and lumen area was conducted.
• Lesion morphology, distribution, macrophage prevalence, and microvessel density were assessed.

Main Results:

• HT recipients with HGR showed smaller external elastic lamina and lumen areas in distal segments compared to NCA patients.
• Lesions in HT recipients were more homogeneous and involved the entire coronary tree compared to NCA.
• Higher macrophage prevalence and increased microvessel counts were observed in HT recipients (both HGR and LGR) versus NCA patients.

Conclusions:

• OCT imaging reveals distinct differences in coronary lesion distribution and morphology between CAV and NCA.
• These OCT findings suggest its potential role in differentiating CAV from NCA in vivo.
• Understanding these differences can guide clinical management and improve patient outcomes.