Monitoring of gadolinium-BOPTA uptake into the vessel wall during magnetic resonance (MR)-guided angioplasty of the peripheral arteries with a paclitaxel/gadolinium-BOPTA-coated balloon: an experimental study at 3 Tesla.

PURPOSE: The success of paclitaxel distribution within the vessel wall during paclitaxel-coated balloon angioplasty to prevent restenosis cannot be monitored under X-ray guidance. The aim of this pilot study was to demonstrate the feasibility of monitoring Gadolinium-BOPTA delivery within the vessel wall during magnetic resonance (MR)-guided paclitaxel/Gadolinium-BOPTA-coated balloon angioplasty of the peripheral arteries. MATERIALS AND METHODS: 6 pigs (47 ±â€Š2 kg) were investigated. All experiments were performed using a 3 Tesla MR scanner. MR-guided bilateral angioplasty of the iliac arteries was performed using a paclitaxel/MR contrast agent-coated balloon catheter. The feasibility of monitoring the delivery of Gadolinium-BOPTA to the vessel wall was assessed in 4 animals. In two additional animals, bilateral stenosis was surgically induced in the iliac arteries. Delivery of paclitaxel to the vessel wall was monitored using a 3 D T1-weighted gradient echo (GE) sequence for delineation of the vessel wall. Normalized signal intensity (SI) of the vessel wall was measured before and repeatedly after the intervention for 45 min. in all animals. RESULTS: Paclitaxel/gadolinium-BOPTA-coated balloon angioplasty was successfully accomplished in all iliac arteries (n = 12). In animals with stenosis MR-angiography demonstrated successful dilatation (n = 4). The normalized SI of the vessel wall on T1-weighted GE images significantly increased after the intervention in all animals with and without stenosis for more than 45 min. (p < 0.001). CONCLUSION: Monitoring of Gadolinium-BOPTA into the vessel wall during MR-guided coated balloon angioplasty is feasible. This is a first step towards providing a tool for the online control of homogenous drug delivery after paclitaxel-coated balloon angioplasty. KEY POINTS: • Monitoring of gadolinium-BOPTA uptake into the vessel wall during MR-guided coated balloon angioplasty is feasible.• Endovascular MR-guided interventions on a 3 Tesla MR scanner are feasible.• This is a first step towards providing a tool for online control of homogenous drug delivery after paclitaxel-coated balloon angioplasty.

[Atrial tumors in cardiac MRI]. / Vorhoftumoren in der kardialen MRT.

Cardiac magnetic resonance imaging (MRI) is an important tool for the diagnosis of cardiac masses. Various cardiac tumors are predisposed to occurring in atrial structures. The aim of this review article is the description of atrial tumors and their morphological features in MRI. In general, cardiac tumors are rare: approximately 0.001 - 0.03 % in autopsy studies. About 75 % of them are benign. The most common cardiac tumor is the myxoma. They are predisposed to occur in the atria and show a characteristically strong hyperintense signal on T 2-wieghted images in MRI. In other sequences a heterogeneous pattern reflects its variable histological appearance. Lipomas exhibit a signal behavior identical to fatty tissue with a typical passive movement in cine imaging. Fibroelastomas are the most common tumors of the cardiac valves. Consisting of avascular fibrous tissue, they often present with hypointense signal intensities. Thrombi attached to their surface can cause severe emboli even in small tumors. Amongst primary cardiac malignancies, sarcomas are most common and favor the atria. Secondary malignancies of the heart are far more common than primary ones (20 - 40 times). In case of known malignancies, approximately 10 % of patients develop cardiac metastasis at the end of their disease. Lymphogenic metastases favor the pericardium, while hematogenic spread prefers the myocardium. Since they are not real atrial tumors, thrombi and anatomical structures of the atria have to be differentiated from other pathologies.