Effects of False Lumen Procedures on Aorta Remodeling of Chronic DeBakey IIIb Aneurysm

Ratio of the false lumen to the true lumen is associated with long-term prognosis after surgical repair of acute type A aortic dissection

Objectives

The aim of this study was to assess potential predictors of aortic events after an emergency surgery for acute type A aortic dissection, especially paying attention to the findings of computed tomography (CT) performed immediately after the surgery.

Methods

Between January 2001 and December 2015, 72 patients, who were diagnosed as having Stanford type A acute aortic dissection with a patent false lumen in the descending thoracic aorta, survived the emergency operation, and had postoperative CT scan data, were included in this study (mean follow-up, 8.2 ± 3.8 years; range 0.8-17.4 years). From the CT scan data, the diameter of the false lumen (FL-D) and true lumen (TL-D) were measured, and the FL-D:TL-D ratio was calculated. Long-term outcomes of the FL-D > TL-D group (n = 30) and the FL-D < TL-D group (n = 42) were compared.

Results

In the late follow-up, 17 aortic events in the downstream aorta were observed. The FL-D:TL-D ratio (P = .01) was an adjusted risk of aortic events in multivariable analysis. The rates of freedom from aortic events at 5 and 9 years were superior in the FL-D < TL-D group than in the FL-D > TL-D group (92.0% and 88.6% vs 81% and 60.7%; log rank P < .05).

Conclusions

Our results suggest that the false lumen:true lumen ratio predicts long-term prognosis after surgical repair of acute type A aortic dissection.

Chronic thoracoabdominal aortic dissection: endovascular options to obliterate the false lumen

Background

Persistent false lumen patency in chronic thoracoabdominal aortic dissections after thoracic endovascular aortic repair (TEVAR) contributes to negative aortic remodeling. We have previously described the evolution of various endovascular techniques to treat persistent false lumen perfusion including false lumen embolization. Objectives of this study are to describe endovascular techniques to obliterate the false lumen and present updated outcomes in a recent series of patients undergoing false lumen embolization for chronic aortic dissection.

Methods

From January 2018 to May 2021, 17 patients with chronic dissection underwent false lumen embolization with coils, iliac plugs, and nitinol plugs. This was often in conjunction with or following TEVAR and balloon fracture fenestration. Mean follow-up 354±324 days.

Results

After false lumen embolization there was no mortality, stroke, spinal cord ischemia, or visceral and limb ischemia. No patients required dialysis, though 1 (5.9%) did experience acute kidney injury. There was 1 (5.9%) patient that required endovascular re-intervention on the thoracoabdominal aorta. No patients underwent subsequent open surgical repair.

Conclusions

TEVAR with adjunctive false lumen embolization and balloon fracture fenestration are techniques to obliterate retrograde flow into the false lumen of chronic thoracoabdominal aortic dissections in appropriately selected patients.

Alternative management of proximal aortic dissection: concept and application

Open surgery remains the mainstay of treatment for acute type A aortic dissection and should be offered to most patients. However, there are elderly patients in which surgical treatment may be deemed extremely high risk or futile. Endovascular treatment approaches have been applied to a small number of these patients and data are limited to case reports and small series. The application of endovascular therapies to ascending aorta is currently limited by anatomical and technical challenges posed by the dynamic motion of the ascending aorta and the proximity of vital structures to intended landing zones (aortic valve, coronary arteries, and supra-aortic branches) and lack of specially designed endografts to address these issues. While thoracic endovascular aortic repair (TEVAR) has replaced open aortic repair for a suitable lesion in distal aortic dissection, some selected patients with type A aortic dissection at high surgical may be candidates. Hence, there is potential because, in proximal (Stanford type A) dissections, 10–30% of patients are not accepted for surgery, and 30–50% are technically amenable for TEVAR. Recent experience has shown that carefully selected patients with favorable anatomical characteristics may be subject to endovascular stent-graft treatment as a last resort with mixed results. Technical improvement is necessary to offer. satisfactory endovascular options in non-surgical candidates.

Late Aortic Expansion After Thoracic Endovascular Aortic Repair for Chronic DeBakey IIIb Dissection

BACKGROUND

The efficacy of thoracic endovascular aortic repair (TEVAR) for chronic DeBakey IIIb aortic dissection is still under discussion. This study was performed to investigate the incidence of and risk factors for late aortic expansion after TEVAR for chronic DeBakey IIIb aortic dissection.

METHODS

From March 2014 to April 2019, a total of 35 patients with chronic DeBakey IIIb aortic dissection underwent TEVAR in our institution. Risk factors for aortic expansion events were examined by stepwise Cox regression analysis. Aortic expansion events were defined as reintervention for expansion or aortic expansion of greater than 5 mm.

RESULTS

No operative death occurred, and the 2-year survival rate was 96.8%. The 1- and 2-year rates of freedom from reintervention were 87.8% and 80.2%, respectively. During follow-up, 11 patients had late aortic expansion events (4 with expansion of the thoracic aorta and 7 with expansion of the abdominal aorta). The 1- and 2-year rates of freedom from aortic expansion were 87.8% and 68.7%, respectively. Significant risk factors for expansion events were aortic dilation at the celiac level (hazard ratio [HR], 1.11; P = .015), saccular aneurysm formation of the false lumen (HR, 5.08; P = .049), and high number of residual large reentries (>5 mm) (HR, 2.78; P = .027).

CONCLUSIONS

In patients undergoing TEVAR for chronic DeBakey IIIb aortic dissection, late aortic expansion in both the thoracic and abdominal aorta remains an important issue. Aggressive additional intervention should be considered for high-risk patients with residual large reentries and aortic dilation at the celiac level.

Temporal pattern of aortic remodelling after endovascular treatment for chronic DeBakey IIIb dissection

OBJECTIVES

Endovascular treatment has emerged as a safe procedure for treating chronic DeBakey IIIb dissection. The objective of this study was to investigate the mid-term outcome and temporal pattern of aortic remodelling after endovascular treatment for DeBakey IIIb dissection.

METHODS

From 2012 to 2017, 85 patients who underwent endovascular aortic repair for DeBakey IIIb dissection were enrolled. The temporal pattern of aortic remodelling in terms of false lumen (FL) thrombosis [level 1 (∼T7), level 2 (T7 ∼ coeliac axis) and level 3 (coeliac trunk ∼ aortic bifurcation)] and aortic diameter [mid-thoracic level (T7), coeliac axis and the largest infrarenal abdominal aorta] was investigated on serial follow-up computed tomography scan.

RESULTS

Eighty-five patients underwent endovascular treatment during the study period. Male sex was a significant risk factor for repetitive reintervention and segments 2 and 3 FL thrombosis. The preoperative FL diameter at T7 was significantly associated with FL diameter regression. The number of visceral vessels from the FL and residual DeBakey IIIb dissection after type A repair were significant factors for FL growth at the coeliac trunk and at the largest infrarenal abdominal aorta. The overall mortality was 3 (3.6%).

CONCLUSIONS

Endovascular treatment is a safe strategy in the management of DeBakey IIIb dissection. However, unfavourable aortic remodelling and repetitive reintervention were expected in male patients with a large number of visceral vessels from the FL and residual DeBakey IIIb dissection after type A repair. Endovascular treatment should be cautiously considered, and close follow-up is required for these patients.

Outcomes of Selective Strategies for Distal Entry Tears After Thoracic Endovascular Aortic Repair in Type B Aortic Dissection

BACKGROUND

Distal entry tears have undesirable influence in type B aortic dissection (TBAD) after thoracic endovascular aortic repair (TEVAR), including inhibition of aortic remolding and increase of late aortic events. Therefore, distal entry tears should be managed. Nowadays, main strategies for managing distal entry tears included total and selective strategies. However, which strategy is better still remains controversial. The objective of the study is to investigate the outcomes of selective strategy for distal entry tears after TEVAR in TBAD.

METHODS

A total of 43 consecutive patients with TBAD with distal entry tears after TEVAR were administered with selective strategy for distal entry tears, including occlusion of the tear in the thoracic aortic segment, thrombosis of the reverse blood flow channel in the false lumen, and selective occlusion of distal entry tears. Mortality, complications, and aortic remolding in early follow-up (12 months after operation) were analyzed.

RESULTS

All 43 patients survived during the follow-up period. Operation was performed again for femoral artery reconstruction in 1 patient who had occlusion of the approach vessel during the follow-up period, and the remaining 42 patients had no uncomfortable symptoms and operation-related complications. The maximum diameter of the aorta was 32.03 ± 6.35 mm and 27.36 ± 4.92 mm, respectively, for before and after reintervention, and the difference was significant (t = 5.899, P < 0.001). The unthrombotic range of the false lumen after reintervention was significantly shrunken in all patients, compared with the range before reintervention.

CONCLUSIONS

Selective strategy was safe and effective, at least in early follow-up. Its effectiveness should be further verified by more clinical observation results and long-term follow-up results.

False lumen embolization as a rescue technique in the setting of acute and chronic dissecting aneurysms as adjunct to thoracic endovascular aortic repair

Complicated type B aortic dissection (TBAD) is a life-threatening condition requiring surgical intervention. One such complication in the acute or chronic setting is aneurysmal degeneration. The dissected aortic wall is weakened, and the pressures in the false lumen are often high. In the past decade, thoracic endovascular aortic repair (TEVAR) has become the treatment of choice for TBAD. TEVAR can be complicated by lack of false lumen thrombosis, increasing the risk of death. We present three cases of TBAD with patent false lumens after TEVAR that were treated by false lumen coil embolization.

Concomitant true and false lumen "parallel thoracic endovascular aortic repair" as an endovascular alternative to open arch/descending aortic reconstruction for chronic DeBakey type I dissection with aneurysmal degeneration

A 77-year-old woman presented with symptomatic thoracic aortic aneurysm within a dissected thoracoabdominal aorta distal to a previous Dacron ascending aortic replacement. She was not a candidate for open repair and had no proximal landing zone for conventional thoracic endovascular aortic repair (TEVAR) resulting from dissection extension into the brachiocephalic vessels. A concomitant parallel graft true and false lumen TEVAR was performed from the distal aortic arch to diaphragm. Follow-up imaging demonstrated successful exclusion of the false lumen aneurysm and successful protection of the true lumen with the adjacent parallel TEVAR device.

False Lumen Occlusion in Chronic Aortic Dissection: The New Generation Candy-Plug II

BACKGROUND

To introduce the new generation Candy-Plug II with a self-closing channel construction inside the plug.

METHODS

The technique of the Candy-Plug II was demonstrated in a 50-year-old patient with residual chronic aortic dissection and thoracic false lumen aneurysm with false lumen backflow after open surgical repair of the ascending aorta for acute type A aortic dissection. The Candy-Plug Technique was applied in addition to a branched arch procedure using a new generation Candy-Plug II for false lumen occlusion. The Candy-Plug II is a short tubular stent graft with a small open channel inside the graft to accommodate the central cannula and allow retrieval of the dilator tip, which closes itself as soon as the dilator tip is removed. The channel inside the graft is unsupported and will collapse and thereby close. This new design obviates additional placement of a plug to occlude the midsection of the first-generation Candy-Plug. After deployment of the Candy-Plug, distal false lumen occlusion was confirmed on final angiogram and postoperative computed tomography scans without any leakage through the Candy-Plug.

CONCLUSIONS

The new generation Candy-Plug II is a useful refinement of the previously available model. It reduces the procedural steps and provides a longer sealing segment.

Left ventricular remodeling in patients with acute type B aortic dissection after thoracic endovascular aortic repair: Short- and mid-term outcomes

BACKGROUND

Left ventricular (LV) remodeling remains unknown in patients with acute Type B aortic dissection (aTBAD) after thoracic endovascular aortic repair (TEVAR) during follow-up.

METHODS

Between May 2004 and January 2016, 163 consecutive patients (136 males, mean preoperative age: 51.06 ± 10.79 years) with aTBAD underwent TEVAR. A linear mixed model was used to evaluate risk factor influencing on LV remodeling and investigate longitudinal changes in LV thickness, diameter, volume, function and mass at preoperation, postoperation, short- and mid-term follow-up.

RESULTS

Median follow-up time was 48.0 months (quartiles 1-3, 31-84 months, maximum 147 months). LV thickness and mass followed a continuous downward trend over time. Interventricular septal thickness at end-diastole significantly decreased at mid-term follow-up (time, p < 0.001: preoperative 11.59 ± 0.14 mm vs mid-term 10.82 ± 0.15 mm, p < 0.001; postoperative 11.40 ± 0.14 mm vs mid-term 10.82 ± 0.15 mm, p = 0.006). LV posterior wall thickness at end-diastole was markedly reduced at mid-term follow-up (time, p < 0.001: preoperative 10.89 ± 0.11 mm vs mid-term 10.02 ± 0.11 mm, p < 0.001; postoperative 10.78 ± 0.13 mm vs mid-term 10.02 ± 0.11 mm, p < 0.001; short-term 10.56 ± 0.15 mm vs mid-term 10.02 ± 0.11 mm, p = 0.021). LV mass index markedly decreased during follow-up (time, p = 0.001: preoperative 129.60 ± 3.55 g/m² vs short-term 119.26 ± 3.19 g/m², p = 0.009; preoperative 129.60 ± 3.55 g/m² vs mid-term 115.79 ± 3.62 g/m², p = 0.003). LV function was improved, but not significantly so, during follow-up. Strict blood pressure control had no influence on LV remodeling. True lumen followed a continuous enlargement trend in terms of proximal thoracic aorta and celiac trunk level during follow-up.

CONCLUSIONS

TEVAR can reverse LV remodeling and LV hypertrophy in patients with aTBAD during follow-up.

Outcomes of Stentless Thoracic Endovascular Aortic Repair for Chronic DeBakey IIIb Aneurysms

BACKGROUND

We introduce a new endovascular procedure for favorable aortic remodeling in patients with chronic DeBakey IIIb (CDIIIb) aneurysms and present outcomes.

METHODS

This study included 19 patients who underwent stentless thoracic endovascular aortic repair (TEVAR) for CDIIIb aneurysms between 2014 and 2016. Stentless TEVAR is defined as an endovascular procedure involving closure of communicating channels or obliteration of the false lumen itself using various materials. Thoracic false lumen thrombosis was defined as there was no flow in the false lumen of the thoracic aorta. Aortic diameter was measured at 3 levels (left subclavian artery, pulmonary artery bifurcation, and celiac axis).

RESULTS

Fifteen of 19 (78.9%) patients demonstrated thoracic false lumen thrombosis. There was no mortality, and the mean follow-up duration was 16.8 months. False and true lumen diameters at the left subclavian and pulmonary artery levels significantly changed after the procedure (false lumen: 22.6 ± 16.6 versus 16.1 ± 14.4 mm, 23.2 ± 14.6 versus 18.0 ± 13.2 mm, p = 0.001 and p = 0.002, respectively; true lumen: 22.7 ± 8.7 versus 27.9 ± 6.3 mm, 19.0 ± 8.3 versus 24.3 ± 6.7 mm, p = 0.001 and p = 0.001, respectively). The number of visceral stent grafts and preoperative true lumen diameter at the pulmonary artery were independent predictors for thoracic false lumen thrombosis (hazard ratio, 3.445, 95% confidence interval, 1.494 to 7.946; p = 0.004; and hazard ratio, 1.106; 95% confidence interval, 1.029 to 1.189; p = 0.006, respectively).

CONCLUSIONS

Stentless TEVAR seems to be a safe procedure and enables favorable aortic remodeling. Thus, this technique can be useful in a selected group of patients with CDIIIb aneurysms.

Favorable Aortic Remodeling Following Serial False Lumen Procedures in a Case of Chronic Type IIIb Dissection

We report a case of acute type I aortic dissection in which an emergency graft replacement of the ascending aorta and innominate artery was performed. We performed false lumen thrombosis through hybrid thoracic endovascular aortic repair to seal the primary entry tear, followed by false lumen obliteration at the level of the descending thoracic aorta, abdominal aorta, and right common iliac artery. Over a period of 4.5 years, we used Amplatzer vascular plugs and coils based on our computed tomography angiography follow-up protocol.

Type B Aortic Dissections: Current Guidelines for Treatment

Stanford type B aortic dissections (TBADs) involve the descending aorta and can present with complications, including malperfusion syndrome or aortic rupture, which are associated with significant morbidity and mortality if left untreated. Clinical diagnosis is straightforward, typically confirmed using CT angiography. Treatment begins with immediate anti-impulse medical therapy. Acute TBAD with complications should be repaired with emergent thoracic endovascular aortic repair (TEVAR). Uncomplicated TBAD with high-risk features should undergo TEVAR in the subacute phase. Open surgical repair is seldom required and reserved only for select cases. It is critical to follow these patients clinically and radiographically in the outpatient setting.