Symptomatic Aortic Bare-Metal Stent Fracture after PETTICOAT Technique for Complicated Type B Aortic Dissection

Clinical effects of hybrid debranching technique for acute Stanford type A aortic dissection

BACKGROUND

To investigate the clinical effects and safety of the hybrid debranching technique for patients with acute Stanford type A aortic dissection (AD).

METHODS

One hundred nine patients with acute Stanford type a AD were selected and divided into observation group and control group according to the different surgical methods. Fifty-five patients in the observation group were treated with hybrid debranching, and 54 patients in the control group were treated with Sun's operation. The operation duration, clamp time, cardiopulmonary bypass duration, volume of blood transfusion, ventilator application duration, duration of stay in the intensive care unit, aortic rupture, second thoracotomy due to hemorrhage, gastrointestinal hemorrhage, stroke, paraplegia, renal failure, and all-cause mortality were recorded. Postoperative follow-up was conducted. The number of cases that underwent follow-up and the number of cases with complete thrombosis of the false aneurysm cavity detected by computed tomography angiography (CTA) was recorded.

RESULTS

The surgical success rate was 100% in both groups, and there were no cases with unplanned secondary surgery. Compared with the control group, only the difference in the volume of blood transfusion was not significantly significant between the two groups (P = 0.052), while the rest of the observation indicators were significantly lower in the observation group than in the control group (P < 0.001 for all). The proportion of cases with complete thrombosis of the false aneurysm cavity was significantly higher in the observation group than in the control group at 3 and 6 months after surgery (P < 0.05).

CONCLUSION

In patients with acute Stanford type A AD involving the arch, the hybrid debranching technique was safe and effective. It was recommended for patients with advanced age and a high risk of intolerance to deep hypothermic circulatory arrest.

Emerging Trends in the Care of Type B Aortic Dissections

Aortic dissection is the most common of the acute aortic syndromes. Acute aortic dissection remains a highly morbid and potentially lethal condition despite contemporary advances in medical and surgical care. Type B aortic dissection (TBAD) is classified as uncomplicated, uncomplicated with high-risk features, and complicated. The role of thoracic endovascular aortic repair (TEVAR) in uncomplicated TBAD remains uncertain and is the topic of ongoing clinical trials. In most complicated cases, TEVAR is effective at restoring visceral and extremity blood flow. TEVAR has also been shown to arrest hemorrhage in the setting of thoracic aortic rupture. TEVAR has been demonstrated to induce satisfactory remodeling in the covered segment of the thoracic aorta, but progressive enlargement of the visceral aorta has led to a variety of techniques designed to promote remodeling in the uncovered aortic segment. There is a need to better define high-risk features so that treatment can be tailored to specific clinical conditions.

Bare Stent Fracture After TEVAR With the Modified Restrictive Bare Stent (RBS) Technique in Type B Aortic Dissections

PURPOSE

The aim was to assess the mid-term aortic remodeling and bare-metal stent (BMS) integrity of the restricted bare stent (RBS) technique reconstruction in aortic dissections.

MATERIALS AND METHODS

This retrospective cohort study included prospectively collected patients treated with the modified RBS technique between 2017 and 2020. The preoperative, postoperative, and last follow-up computed tomographic (CT) scans were analyzed in the centerline at the mid-descending, celiac trunk (CeT), and the mid-abdominal levels for false lumen (FL) patency, aortic diameter, and true lumen (TL) diameter changes. Bare-metal stent integrity was assessed in the 3-dimensional multiplanar reformats.

RESULTS

The median follow-up of the cohort (n=17) was 26 (11, 45) months. The procedure was mainly performed with the Relay NBS endograft (15/17; 88%) + E-XL BMS (17/17; 100%). Postoperative mortality, paraplegia, stroke, renovisceral vessel loss, and type I and III endoleaks were not observed. BMS fractured in 6 patients (6/17; 36%), damaged the dissection flap in 4/17 (24%), and led to the reperfusion of the FL and re-interventions with TEVAR (4/17; 24%). Two patients without FL reperfusion showed stable CT follow-ups 13 and 17 months after the fracture diagnosis. The TL expansion was seen at all landmarks and peaked in the thoracic aorta (+10; 6, 15; p<0.001). The FL thrombosis after modified RBS was only relevant in the thoracic aorta (p<0.001) and at CeT (p=0.003). The aortic diameter was stable in the thoracic aorta and increased at distal landmarks (CeT [+5; 1, 10; p=0.001]; mid-abdominal [+3; 1, 5; p=0.004]).

CONCLUSION

The modified RBS technique could not stop aortic growth below the diaphragm and prevent new membrane rupture due to the fractures of the BMS and consecutive flap damage with the reperfusion of the FL.

CLINICAL IMPACT

The treatment of complicated type B aortic dissections with TEVAR has become a standard. Particularly, patients with true lumen collapse and malperfusion may benefit from a more aggressive treatment strategy including proximal TEVAR and distal bare-metal stent implantation to re-open the true lumen and to prevent distal stent-induced new entry. However, this study reports the challenges of this approach with a high rate of bare-metal stent fractures during the follow-up. The fractures that occurred at the site of vertical nitinol bridges led to the dissection membrane ruptures and the reperfusion of the false lumen with consecutive dilatation. A close follow-up is mandatory to detect this complication and to treat the patients with TEVAR extension.

Staged Hybrid Single Lumen Reconstruction (TIGER) in Management of Chronic Symptomatic Complex Type B Aortic Dissection, Techniques, and Literature Review

BACKGROUND

Endovascular intervention for chronic symptomatic type B aortic dissection (CS-TBAD) induces aortic wall stress with negative hemodynamic cardiovascular consequences. CS-TBAD risks increased morbidity and mortality due to septum maturation with significant impact on false lumen modulation, and partial lumen thrombosis conveying the worst outcome. The aim of the TIGER technique is total aortic remodeling with true lumen expansion, false lumen regression and complete thrombosis, and stabilization of overall aortic diameter.

METHODS

We report 5 cases of aortic dissection with a mean follow-up of 16 months (6-28 months). All had aneurysmal dilation, with 3 having acute pan aortic dissection and 2 having CS-TBAD. All were managed by sTaged HybrId sinGle lumEn Reconstruction (TIGER). Our first approach was to create one single lumen from the supraceliac, infradiaphragmatic aorta to both common iliac arteries with open surgical patching of the visceral arteries; then, we performed a TEVAR 3 months later.

RESULTS

Three patients required a left subclavian artery chimney graft and one required bilateral subclavian to carotid artery transposition. No spinal drainage was required, and all patients had intraoperative transesophageal echo for wire guidance. We had no aortic rupture or retrograde type A dissection, and we experienced no renal, visceral, cardiac, pulmonary, or spinal complications. All patients, but one, went off their antihypertensive medication. All patients had normal estimated glomerular filtration rate postoperatively, and they all demonstrated accelerated aortic modulation.

CONCLUSIONS

TIGER was not only effective at the semiacute stage to initiate remodeling and prevent malperfusion, it also facilitated a straightforward TEVAR at stage 2, which was made easier by avoiding visceral branch stenting. Moreover, it decreased the length of aortic segment, which was stented, thereby avoiding critical shattering, branch dislodgment, and visceral compromise; spinal ischemia; and negative cardiovascular consequences.