Covered or Not, Here I Come: Stanford Type B Aortic Dissection Repair With a Covered and Uncovered Stent Hybrid Technique

Figures

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  Figure 1. Pre-Procedural Planning With Three-Dimensional Model Rendering The pre-procedural planning of a patient with an aortic aneurysm includes the three-dimensional rendering of the aorta. The patient’s aorta is printed using three-dimension volume software, uploaded from our institutional picture archiving and communication system (A). The printed aorta was cured, shown on a blue towel, next to one of our institution's three-dimensional printers (B). The completely cured three dimensionally printed aorta is shown (C). The printed aortic model shows the aortic aneurysm, visceral segment, and bilateral common iliac arteries. This model will be used to ease in-vitro visualization and simulation before endovascular repair in-vivo.

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  Figure 2. Stanford B Aortic Dissection An illustration of a Stanford B aortic dissection, originating immediately distal to the LSC to the aortic bifurcation, is shown (A). The AA, BA, LC, TL, and FL, dissection flap (blue line indicated by black arrows), DA, CA, and SMA are identified. A three-dimensional acrylic model of a Stanford B aortic dissection with an indwelling dissection flap (white arrow) is shown (B). The flap originates immediately distal to the left subclavian artery and terminates in the region of the aortic bifurcation. Computed tomography angiography of a Stanford B aortic dissection in the “candy cane,” or sagittal view is shown (C). The true lumen (blue arrow), false lumen (green arrow), and dissection flap (red arrow) are identified. The dissection extends immediately distal to the left subclavian artery, and to the aortic bifurcation. The true lumen supplies flow to the celiac axis and superior mesenteric artery. LSC: left subclavian artery; AA: ascending aorta; BA: brachiocephalic artery; LC: left carotid artery; TL: dissection true lumen; FL: false lumen; DA: descending aorta; CA: celiac axis; SMA: superior mesenteric artery

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  Figure 3. Axial Computed Tomography Angiography of a Pre-Procedural Stanford B Aortic Dissection A pre-procedural axial computed tomography angiogram shows the caliber sizes of the respective true (blue arrow) and false (green arrow) dissection lumens. The aortic diameter measures 27.8 millimeters in diameter at this level. The false lumen measures 17.8 millimeters and is noticeably larger than the true lumen, measuring 10 millimeters.

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  Figure 4. Thoracic Endovascular Aortic Repair of a Stanford B Aortic Dissection An illustration of the covered endograft being advanced over a stiff guidewire into the thoracic aorta before deployment is shown (A). A guidewire (black arrows) was positioned from the right femoral artery and was advanced to the AA. The covered aortic stent is within the true lumen. The BA, LC, LSC, TL, and FL, dissection flap (blue line indicated by black arrows), DA, CA, and SMA are identified. An intraoperative fluoroscopic guided angiogram shows the covered aortic device before deployment within the true lumen (black arrow), advanced over a stiff guidewire (B). Contrast can be identified within the false lumen (red arrow), abutting the non-deployed covered aortic device within the true lumen. AA: ascending aorta; BA: brachiocephalic artery; LC: left carotid artery; LSC: left subclavian artery; TL: dissection true lumen; FL: false lumen; DA: descending aorta; CA: celiac axis; SMA: superior mesenteric artery

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  Figure 5. Radial Force of the Covered Endograft to Exclude the False Lumen An illustration of the covered endograft before deployment is shown (A). As the operator deploys the covered endograft, the radial force displaces the false lumen towards the aortic wall (green arrows). The guidewire (black arrows), AA, BA, LC, LSC, TL, and FL, dissection flap (blue line indicated by black arrows), DA, CA, and SMA are identified. An illustration following the deployment of the covered endograft shows the expansion of the covered endograft within the true lumen (B). The false lumen and dissection flap remain but will continue to diminish over time due to the continuous radial force applied by the covered endograft (black arrow). The distal landing zone of the covered endograft is just above the celiac axis. The guidewire (black arrows), AA, BA, LC, LSC, FL, dissection flap (blue line indicated by black arrows), CA, and SMA are identified. A three-dimensional acrylic model with a deployed covered aortic device within the true lumen is shown (C). The deployed covered aortic device (white arrow) excludes the proximal portion of the dissection flap, but the distal visceral dissection remains. An…

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  Figure 6. Bare Metal/Open Cell Exclusion of the False Lumen Dissection in the Visceral Segment and Abdominal Aorta An illustration of the bare metal/open cell stent deployed within the body of the covered endograft is shown (A). The expanded covered endograft within the true lumen is identified (black arrow). The bare metal/open cell stent is within the true lumen and traverses the visceral segment of the abdominal aorta (black arrow). Perfusion of the visceral segment is maintained as a result of an open cell configuration. A combination of the covered endograft and bare metal/open cell stent reduces the false lumen. The guidewire (black arrows), AA, BA, LC, LSC, dissection FL, dissection flap (blue line indicated by black arrows), CA, and SMA are identified. A three-dimensional acrylic model with both the deployed covered aortic device within the true lumen (white arrow), and bare metal/open cell stent within the true lumen (white arrow) is shown (B). An intraoperative fluoroscopic guided angiogram of the bare metal/open cell stent at the distal landing zone is shown (C). The deployed uncovered aortic device (white arrow) is within the true lumen (blue arrow), measuring 22.2 millimeters…

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  Figure 7. Post-Procedural Short and Mid-Term Surveillance A one month post-procedural sagittal computed tomography angiogram shows the bare metal/open cell stent within the true lumen (blue arrow), excluding the false lumen (green arrow), and terminating appropriately just above the aortic bifurcation (A). The true lumen is noticeably larger in diameter than the false lumen, measuring 23.6 millimeters. A four-month post-procedural sagittal computed tomography angiogram of the same patient shows the bare metal/open cell stent within the true lumen (blue arrow), continuing to exclude the false lumen (green arrow), and terminating appropriately just above the aortic bifurcation (B). The expansile capability of nitinol within the open cell/bare metal stent has increased the true lumen diameter to 25.3 millimeters, while further diminishing the size of the false lumen after four months. A nine-month post-procedural sagittal computed tomography angiogram of the same patient again shows the bare metal/open cell stent within the true lumen (blue arrow), continuing to exclude the false lumen (green arrow), and terminating appropriately just above the aortic bifurcation (C). There is a marginal…

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  Figure 8. Mid-Term Surveillance True Luminal Patency of Thoracic Endovascular Aortic Repair The initial pre-procedural axial CT angiogram (Figure 3) shows the caliber sizes of the respective true (blue arrow) and false (green arrow) dissection lumens (A). The aortic diameter measures 27.8 millimeters in diameter at this level. As demonstrated (Figure 3) the false lumen measures 17.8 millimeters and is noticeably larger than the true lumen, measuring 10 millimeters. A comparison nine-month post-procedural axial CT angiogram of the same patient shows the caliber sizes of the respective true (blue arrow) and false (green arrow) dissection lumens after thoracic endovascular aortic repair with the covered and uncovered stent hybrid technique (B). The true lumen is noticeably larger in diameter than the false lumen, measuring 24.3 millimeters. The open cell/bare metal stent continues to exclude the false lumen after nine months.

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  Figure 9. Aortic True Lumen Patency Over Time The graph shows true lumen patency throughout the surveillance period. All patients in the immediate post-procedural period demonstrated a noticeable increase in true lumen patency. For the patients able to follow-up in the short and mid-term surveillance periods, all patient aortic true lumens remained patent, five showing continued expansion.