A Novel Ferumoxytol-enhanced Cardiac Magnetic Resonance Imaging for the Detection of Intracardiac Thrombus

The incidence of thrombosis in ventricular aneurysm was reported to be 35%-40%, which may lead to systemic thromboembolism. Patients with ventricular aneurysm without detectable thrombus are not routinely treated with anticoagulation. Therefore, the accuracy of intracardiac thrombus detection has an important impact on clinical management decisions. Currently, transthoracic echocardiography is the most commonly used method to detect intracardiac thrombus, but its sensitivity and positive predictive value are low. Cardiac magnetic resonance has a higher diagnostic accuracy for intracardiac thrombus, and its sensitivity and positive predictive value are higher than those of transthoracic echocardiography and CT. However, the gadolinium-based contrast agents commonly used for enhanced magnetic resonance imaging have some problems such as nephrogenic systemic fibrosis, gadolinium deposition in the brain, and short imaging time. Ferumoxytol, a superparamagnetic iron oxide nanoparticle, can be used for off-label enhanced magnetic resonance imaging. Its long intravascular half-life makes it suitable for enhanced magnetic resonance imaging with complex scanning procedures and long repetitive scans. Ferumoxytol is cleared from the blood pool by macrophages of the reticuloendothelial system, mainly in the spleen and lymph nodes. Therefore, ferumoxytol has a favourable safety even in adults and children with end-stage renal failure. The aim of this study is to evaluate the effectiveness of a novel ferumoxytol-enhanced cardiac magnetic resonance in detecting intracardiac thrombus in patients with ventricular aneurysm and after percutaneous ventricular reconstruction.