Title: Magnetic Resonance Imaging for Aortic Dissection
Abstract: We would like to congratulate the authors on their review of imaging for thoracic aortic disease.1Rousseau H. Chabbert V. Maracher M.A. El Aassar O. Auriol J. Massabuau P. et al.The importance of imaging assessment before endovascular repair of thoracic aorta.Eur J Vasc Endovasc Surg. 2009; 38: 408-421Google Scholar However, we would like to comment on the section regarding dissection. Multidetector contrast-enhanced computed tomography (CT) remains the most widely available modality for imaging patients with this disease, but has some limitations which may be misleading. The images acquired are a representation of one moment in the cardiac cycle and these static images may not illustrate the complex anatomical and functional changes occurring in aortic dissection. The dimensions of the true and false aortic lumens will vary with systole and diastole and this will have an effect on factors such as device sizing and determining dynamic from static obstruction. Magnetic resonance imaging (MRI) with ECG-gating is able to give static and dynamic high-resolution information in a single examination. False lumen thrombosis is accepted as an important factor in determining the prognosis of patients presenting with dissection, and is diagnosed on CT by the absence of contrast in the false lumen on first pass imaging.2Bernard Y. Zimmermann H. Chocron S. Litzler J.F. Kastler B. Etievent J.P. et al.False lumen patency as a predictor of late outcome in aortic dissection.Am J Cardiol. 2001 Jun 15; 87: 1378-1382Google Scholar A delayed second scan may detect late enhancing structures but the ideal timing for this will be related to both the cardiac output and local flow conditions. MRI is able to deliver anatomical and functional information in a single scan and compared with multidetector contrast-enhanced CT and has the added benefit of not using ionising radiation. The next generation of endoluminal devices will be more conformable to the aortic arch and MRI generated data will allow the use of shorter endoluminal devices in patients requiring intervention. Response to comment on “Patients undergoing cardiac surgery with asymptomatic unilateral carotid stenoses have a low risk of perioperative stroke”European Journal of Vascular and Endovascular SurgeryVol. 39Issue 4PreviewThank you for your comments regarding our study which concluded that patients with unilateral, asymptomatic carotid stenoses undergoing coronary artery bypass grafting (CABG) have a low risk of stroke.1 You propose that CABG patients require routine evaluation of plaque morphology and that prophylactic carotid interventions should be offered to those with ‘vulnerable’ plaques. However, unless I am mistaken, no-one has conclusively shown that asymptomatic ‘vulnerable’ plaques pose any greater risk of procedural stroke during cardiac surgery. Full-Text PDF Open ArchiveResponse to ‘Magnetic Resonance Imaging for Aortic Dissection’European Journal of Vascular and Endovascular SurgeryVol. 39Issue 4PreviewWe read with great interest the commentary by RE Clough, T Schaeffter and PR Taylor about the importance of MRA in aortic dissections. Nevertheless, controversy concerning the superiority of multidetector computed tomography (MD-CT) versus MRI still exists. Full-Text PDF Open Archive