CT imaging of myocardial scars with collagen-targeting gold nanoparticles

In the setting of myocardial ischemia, recovery of myocardial function by revascularization procedures depends on the extent of coronary disease and myocardial scar burden. Currently, computed tomographic (CT) imaging offers superior evaluation of coronary lesions but lacks the capability to measure the transmural extent of myocardial scar. Our work focuses on determining if collagen-targeting gold nanoparticles (AuNPs) can effectively target myocardial scar and provide adequate contrast for CT imaging. AuNPs were coated with a collagen-homing peptide, collagen adhesin (CNA35). Myocardial scar was created in mice by occlusion/reperfusion of the left anterior descending coronary artery. Thirty days later, un-gated CT imaging was performed. Over 6 h, CNA35-AuNPs provided uniform and prolonged opacification of the vascular structures (100-130 HU). In mice with larger scar burden, focal contrast enhancement was detected in the myocardium, which was not apparent within that of control mice. Histological staining confirmed myocardial scar formation and accumulation of AuNPs.From the Clinical EditorThis team of investigators presents a collagen-targeting gold nanoparticle-based approach that enables the imaging of myocardial scars via CT scans in a rodent model. This information would enable clinicians to judge the recovery potential of myocardium more accurately than the current CT-scan based approaches.

Graphical AbstractHere we present the results on the development of a targeted radiocontrast agent based on gold nanoparticles (AuNPs). To enable homing to myocardial scar (MI), AuNPs are coated with a highly specific collagen-homing peptide (CNA35). MI scar was created in mice and CT imaging was performed 30 days later with a GE Ultra flat panel CT scanner. CNA35-AuNPs provided prolonged vascular enhancement after injection of our gold nanoparticles into C57BL/6 mice. Also, focal contrast enhancement was detected in the infarcted myocardium, which was not apparent within that of control mice. Histological staining confirmed myocardial scar formation and accumulation of AuNPs.Figure optionsDownload high-quality image (374 K)Download as PowerPoint slide