How to Guide Stent-Graft Implantation in Type B Aortic Dissection?

Abstract

Background— Despite growing interest in stent-graft implantation for type-B aortic dissection, there are no established recommendations to prepare and perform an implantation procedure. Methods and Results— We directly compared angiography (ANGIO), transesophageal echocardiography (TEE), and intravascular ultrasound (IVUS) intraprocedually before and after placement of 48 stent grafts in 42 consecutive patients (12 women, 61±11 years of age) with acute and chronic type-B aortic dissection for both usefulness and capability to guide aortic stent-graft implantation. Both IVUS and TEE are superior to ANGIO to identify multiple entries (52 and 43 versus 34; P <0.005 each), to diagnose false-lumen slow flow after stent-graft implantation (32 and 31 versus 24; P <0.005 each) and to detect incomplete stent apposition (18 and 16 versus 8; P <0.005 each). In comparison with ANGIO, guide wire position over the entire length of the aorta was documented more frequently by TEE and IVUS (40 and 42 versus 25; P <0.001 each). In 4 patients with abdominal extension of the dissection, only IVUS was able to accurately identify the false lumen over the entire length of the diseased aorta. TEE was superior to IVUS and ANGIO in the detection of endoleaks (5 versus 0 and 1; P <0.05 each). Intraprocedural ANGIO, TEE, and IVUS had been performed without complications in all patients. Conclusions— TEE in conjunction with ANGIO appears to be advantageous and adds incremental information to safely guide stent-graft placement in type-B aortic dissection. Additional use of IVUS was found to be helpful in patients with complex anatomy and abdominal extension of the dissection.

Transesophageal Ultrasound Guidance for Endovascular Interventions on the Aorta

“…The role of transesophageal echocardiography (TEE) in the assessment of the thoracic aorta and acute aortic syndromes is well recognized. 5 6 Although some authors start to recognize the potential applications of TEE in guiding thoracic endovascular repair, 6 7 8 9 its role is not well defined yet. In recent years, the addition of three-dimensional (3D) imaging has improved the anatomical definition of echocardiography and has expanded its applications.…”

“…Diagnostic proof of dissection relies on separating TL from FL; the TL is usually smaller in size with higher flow velocity and pulsatile flow in systole on color Doppler 8 imaging. M-mode is very accurate in demonstrating any expansion of the TL in systole and differentiating artifact from true dissections ( Fig.…”

“…As TEVAR requires fluoroscopic guidance during the procedure, 23 TEE as an adjunctive intraoperative imaging technique can provide incremental information before, during, and after the procedure, thus increasing both success and safety of the intervention. 8…”

“…The sensitivity of TEE to detect residual leaks in the acute phase (after the stent-graft deployment) is higher than fluoroscopy or CT due to its excellent spatial and temporal resolution and Doppler signal. 8 It is mandatory to rule out retrograde dissection into the aortic arch and proximal ascending aorta. 24 Also, when possible, it should be evaluated whether the supra-aortic branches have been jailed by the stent-graft although the latter is often difficult to see on TEE alone.…”

“…In addition, simultaneous imaging and delineation of intracardiac anatomy is not possible with intravascular ultrasound. 8…”