A pitfall of false lumen embolization in chronic aortic dissection: intimal injury caused by the embolization device edge

Open and endovascular reinterventions after Candy Plug false lumen embolization of type B aortic dissection

OBJECTIVE

In the majority of patients with chronic type B aortic dissection, there is persistent retrograde flow in the false lumen (FL) through distal re-entry tears. Among several endovascular techniques proposed for FL management, the "Candy Plug" (CP) technique has gained acceptance with good early results. The aim of this study is to report the types and outcomes of open and endovascular reinterventions and identify mechanisms of procedure failure as well as other causes for reinterventions.

METHODS

All patients with type B aortic dissection submitted to thoracic endovascular aneurysm repair and CP implantation for FL embolization from January 2016 to December 2022 at our institution were included in this study. The preoperative, intraoperative, and postoperative data of the primary intervention and secondary reinterventions, when performed, were prospectively collected and retrospectively analyzed. Preoperative and postoperative computed tomography angiography were also analyzed.

RESULTS

During the study period, 33 patients were submitted to thoracic endovascular aneurysm repair and CP implantation. Twenty-three patients (69.7%) showed thoracic FL complete thrombosis with aortic stability or positive remodeling at a mean follow-up of 45 ± 23.1 months. Ten patients (30.3%) underwent aortic reinterventions (male, n = 9; mean age, 60.5 ± 7.6 years). Of these 10 patients, in four patients, complete thrombosis of the FL was never achieved, leading to ongoing perfusion of the FL, defined as "primary failure." The other six patients underwent reinterventions for different causes: two patients, after initial sealing, showed a progressive enlargement of the abdominal FL leading to distal degeneration. One patient showed proximal degeneration, two patients showed a type II thoracoabdominal aortic aneurysm and CP implantation was used as a planned procedure to reduce the extent of the surgical procedure, and one patient had recurrent, intractable back pain despite complete thrombosis of the FL. Reinterventions were open in five cases and endovascular in five. One in-hospital death (postoperative day 27) after a type II thoracoabdominal aortic aneurysm open repair was recorded. In addition, two cases of delayed spinal cord ischemia after open reintervention were recorded: one resulting in permanent paraplegia and one transitory with complete recovery.

CONCLUSIONS

The CP technique was safe and effective; however, a significant rate of aortic-related reintervention was observed. Several mechanisms led to reinterventions either in terms of "primary failure" of the CP or subsequent aneurysmal degeneration. Complex reinterventions were often necessary, with a high rate of major complications in case of open repair. Life-long and closer surveillance might be required in these patients.

Self-occluding Candy-Plug: Implantation Technique to Obtain False Lumen Thrombosis in Chronic Aortic Dissections

PURPOSE

To describe the implantation steps of the latest generation of candy-plug device (third CP generation [CP III]) and to illustrate its possible pitfalls by discussing a case in whom this device was employed to occlude the false lumen (FL) of a chronic type B aortic dissection.

TECHNIQUE

A 69 year-old male patient who underwent a frozen elephant trunk arch repair due to residual type A aortic dissection developed a FL aneurysmal degeneration limited to the descending thoracic aorta. Two thoracic stent-grafts were deployed into the true lumen up to the celiac trunk origin. Then, the FL was occluded with a self-occluding CP III device (Cook Medical, Bloomington, Indiana), placed at the same level as the distal thoracic stent-graft. The distal un-stented sleeve was pushed upward to allow immediate occlusion of its central lumen, avoiding interference with reno-visceral arteries arising from the FL. Both intraoperative transesophageal echocardiography and follow-up computed tomographic angiography scan demonstrated complete FL thrombosis.

CONCLUSION

The introduction of CP III with its self-occluding mechanism helped to shorten and standardize the procedure. However, adjunctive steps may be needed to immediately obtain FL occlusion and avoid hampering the perfusion of vessels arising from the FL.

Evaluation of false lumen occluders implanted in the abdominal aorta false lumen

OBJECTIVE

Management of postdissection thoracoabdominal aneurysms with a fenestrated and/or branched endograft (F/BEVAR) is associated with favorable outcomes. Treatment should include both true lumen endografting and false lumen occlusion (FLO). Favorable results have recently been reported for FLO in the false lumen of the thoracic aorta. The purpose of this study is to analyze the results of FLO of the abdominal aorta in patients treated for post dissection thoracoabdominal aneurysm.

METHODS

A multicenter retrospective analysis of prospective data of consecutive patients managed for post dissection thoracoabdominal aortic aneurysm from April 2019 to December 2022 with F/BEVAR associated with FLO in the abdominal false lumen was conducted. The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) was followed. Baseline demographics, operative details, and early outcomes (mortality, length of stay) were recorded. Primary endpoints were technical and clinical success. FLO technical success was defined as complete occlusion of false lumen backflow above the FLO on completion angiogram.

RESULTS

During the 3-year study, 23 patients were treated for post dissection thoracoabdominal aneurysm with F/BEVAR and the use of abdominal FLO. Twenty-one patients (91.3%) had received prior endovascular treatment. The technical and clinical success was 95.7%. The abdominal FLO had a technical success rate of 78.3%. The median diameter of the FLO was 34 mm. No patient died during the perioperative period, and one patient had spinal cord ischemia (4.3%) with partial recovery. Six patients (26.1%) required early reintervention. The median duration of hospitalization in the intensive care unit and overall was 1 day (interquartile range, 0-3 days) and 7.5 days (interquartile range, 2-22 days), respectively. During the mean follow-up of 9.9 ± 9.0 months, no patient died. False lumen occlusion was complete or partial in nine (39.1%) and nine (39.1%) patients, respectively. No aortic rupture occurred during follow-up. Maximum aortic diameter decreased in 48% and remained stable in 39% of cases.

CONCLUSIONS

Abdominal aorta FLO during endovascular treatment of post dissection thoracic abdominal aortic aneurysm is associated with favorable outcomes. It offers an additional staging therapeutic option before extensive aorto-bi-iliac coverage, associated with low spinal cord ischemia rates. FLO also provides high rates of false lumen occlusion and false lumen remodeling during follow-up. Longer follow-up and larger cohorts are required to confirm these very promising early findings.

Custom Made Candy Plug for Distal False Lumen Occlusion in Aortic Dissection: International Experience

OBJECTIVE

To evaluate early and midterm outcomes of the Candy Plug (CP) technique for distal false lumen (FL) occlusion in thoracic endovascular aortic repair for aortic dissection (AD) in a more real world cohort of patients from an international multicentre registry.

METHODS

A multicentre retrospective study was conducted of all consecutive patients from the contributing centres with subacute and chronic AD treated with the CP technique from October 2013 to April 2020 at 18 centres.

RESULTS

A custom made CP was used in 155 patients (92 males, mean age 62 ± 11 years). Fourteen (9%) presented with ruptured false lumen aneurysms. Technical success was achieved in all patients (100%). Clinical success was achieved in 138 patients (89%). The median hospital stay was 7 days (1 - 77). The 30 day mortality rate was 3% (n = 5). Stroke occurred in four patients (3%). Spinal cord ischaemia occurred in three patients (2%). The 30 day computed tomography angiogram (CTA) confirmed successful CP placement at the intended level in all patients. Early complete FL occlusion was achieved in 120 patients (77%). Early (30 day) CP related re-intervention was required in four patients (3%). The early (30 day) stent graft related re-intervention rate was 8% (n = 12). Follow up CTA was available in 142 patients (92%), with a median follow up of 23 months (6 - 87). Aneurysmal regression was achieved in 68 of 142 patients (47%); the aneurysm diameter remained stable in 69 of 142 patients (49%) and increased in five of 142 patients (4%). A higher rate of early FL occlusion was detected in the largest volume centre patients (50 [88%] vs. 70 [71%] from other centres; p = .019). No other differences in outcome were identified regarding volume of cases or learning curve.

CONCLUSION

This international CP technique experience confirmed its feasibility and low mortality and morbidity rates. Aortic remodelling and false lumen thrombosis rates were high and support the concept of distal FL occlusion in AD using the CP technique.

Initial Experience with a Modified “Candy-Plug” Technique for False Lumen Embolization in Chronic Type B Aortic Dissection

Background

Persistent distal false lumen (FL) perfusion after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) can lead to aneurysmal degeneration and an increased risk of rupture. We have presented our initial experience using a modified "candy-plug" (CP) technique for FL embolization.

Methods

From February 2021 to July 2022, we treated six patients using the modified CP technique. All the patients had undergone prior or simultaneous TEVAR for chronic TBAD with persistent FL perfusion and aneurysm expansion. Bilateral common femoral artery access was obtained, and intravascular ultrasound was used to confirm wire access in the true lumen (TL) and FL. A conformable TAG device (W.L. Gore & Associates, Flagstaff, AZ) was used in four cases and an Excluder aortic cuff (W.L. Gore & Associates) in two cases. The device was modified by placing a constraining "napkin-ring" suture through the middle segment of the device. Femoral sheaths were placed in the TL and FL. A standard TL TEVAR extension was performed at the level of the celiac artery (zone 5). Next, the CP device was advanced and deployed in the FL, distally aligning it with the TL device. An appropriately sized Amplatzer II plug (Abbot Vascular, Santa Clara, CA) was then deployed in the constrained segment of the modified stent graft. Completion angiography was performed to confirm successful FL embolization.

Results

Technical success was defined as successful deployment of the CP device in the FL. The technical success rate was 100% (six of six patients). Clinical success was defined as the cessation of aneurysm growth on follow-up computed tomography angiography. No 30-day mortality, myocardial infarction, stroke, spinal cord ischemia, access site complications, or aortic-related reinterventions occurred. Surveillance imaging at a mean follow-up of 10 months confirmed clinical success (stable aneurysm size or shrinkage) for all five patients with follow-up data available.

Conclusions

The modified CP embolization technique is a promising solution for persistent distal FL perfusion after TEVAR for TBAD. Further investigation is required to determine the long-term durability of this technique as an adjunct to TEVAR to promote aortic remodeling.

Fate and Consequences of the False Lumen after TEVAR in Type B Aortic Dissection

BACKGROUND

Type B aortic dissection (TBAD) occurs due to an entry tear in the intimal layer of the aorta distal to the origin of the left subclavian artery where blood enters the newly formed false lumen (FL) and extends distally or proximally to form a dissection over an indeterminate length of the aorta which, over time, may eventually rupture. Thoracic endovascular aortic repair (TEVAR) aims to seal off the entry tear proximally with the stent-graft, occluding the origin of the dissection and excluding the FL. Nevertheless, in some cases, the perfusion to the FL is maintained, hindering the aortic remodelling process and increasing the risk of aneurysmal degeneration and rupture, particularly in the abdominal aorta where evidence suggest that remodelling is slower. This review examines the long-term effects of a patent or partially thrombosed FL on clinical outcomes following TEVAR in TBAD, also highlighting the pathological processes behind negative aortic remodelling. Another aim of this review is to provide an overview and appraisal of the currently available techniques for managing a patent or partially thrombosed FL to prevent long-term morbidity occurring.

METHODS

A comprehensive literature search was performed using several search engines including PubMed, Ovid, Google Scholar, Scopus, and Embase to identify and extract relevant studies.

RESULTS

Evidence in the literature show that a partially thrombosed FL is more dangerous than a patent FL due to the occlusion of the distal re-entry tears, impeding outflow and increasing mean arterial and diastolic pressures, whereas the latter is decompressed via distal re-entry sites. FL thrombosis and satisfactory remodelling is sometimes achieved in as few as 40% of patients after TEVAR due to the maintained perfusion of the FL either at the level of the thoracic or abdominal aorta. However, although the thoracic aorta is predominantly covered by the TEVAR stent-graft, poorer remodelling and more dilation is seen in the abdominal aorta. Several techniques are available to embolize the FL, including the Provisional Extension to Induce Complete Attachment, Stent Assisted Balloon Induced Intimal Disruption and Relamination in Aortic Dissection Repair, candy-plug, and Knickerbocker techniques.

CONCLUSIONS

The management of TBAD is invariably TEVAR to seal off the proximal entry tear while extending the repair distally to completely exclude the FL. A risk of aortic wall dilatation distal to TEVAR stent-graft remains; hence, regular monitoring and accurate imaging are essential. At present, a patent FL can be treated using a range of different endovascular techniques.

Clinical Utility of the Candy-Plug Technique Using an Excluder Aortic Extender

Objective: To describe the clinical utility and technical aspects of the candy-plug technique using an Excluder aortic extender (Ex-cuff) for false lumen (FL) occlusion in chronic aortic dissection. Materials and Methods: This is a retrospective study analyzing seven consecutive patients (mean age, 63 years; range, 44-78 years; 6 men) with aneurysmal dilatation or rupture in chronic aortic dissection. All patients had undergone thoracic endovascular aortic repair with FL occlusion using this technique. We assessed technical (deployment accuracy) and clinical (no FL backflow on the latest contrast-enhanced computed tomography) success. Results: Technical success was obtained in six patients (86%). Technical failure was caused by the malposition of the candy-plug. The mean follow-up period was 593 days (range, 222-1225 days). Clinical success was obtained in four (57%), and incomplete Amplatzer Vascular Plug (AVP) embolization was seen in two. There was no enlarged FL after the procedure, and all patients are alive during the follow-up periods. Conclusion: The candy-plug technique using an Ex-cuff may be a feasible option; however, it takes time to achieve complete AVP embolization. Therefore, using additional embolic materials should be considered when we use it for the rupture case. (This is a translation of Jpn J Endovasc Interv 2018; 19: 29-35.).

Aortic Remodeling After Custom-Made Candy-Plug for Distal False Lumen Occlusion in Aortic Dissection

PURPOSE

To report a single-center experience with the use of a custom-made Candy-Plug (CP) for distal false-lumen (FL) occlusion in subacute and chronic aortic dissection (AD).

MATERIALS AND METHODS

A retrospective single-center analysis was conducted on consecutive patients with subacute and chronic AD who were treated with a custom-made CP for distal FL occlusion using 3 design generations (CP I to CP III) from October 2013 to September 2019.

RESULTS

A custom-made CP was used in 57 patients. Of these, 34 patients (29 males, mean age 62±10 years) were treated with a CP I vs 23 patients (16 males, mean age 59±17 years) with CP II/III. Technical success was achieved in 57 (100%) patients. Clinical success was achieved in 54 (95%) patients; 33 (97%) in CP I group vs 21 (91%) patients in CP II/III group, p=0.116. The mean hospital stay was 10±8 days (9±5 days in CP I group vs 13±9 days in CP II/III, p=0.102). The 30-day computed tomography angiography (CTA) confirmed successful CP placement at the intended level in all patients within both groups. Early complete FL occlusion was achieved in 50 (88%) patients; 30 (88%) patients in CP I group vs 20 (87%) in CP II/III group, p=0.894. Follow up CTA was available in 44 (77%) patients. Of these; 30/34 (88%) patients in CP I group with mean follow-up 29±17 months) vs. 14/23 (61%) patients with mean follow-up 14±5 months in CP II/III group. Thoracic aortic remodeling was achieved in 34/44 (77%) patients; 25/30 (83%) patients in CP I group vs 9/14 (64%) patients in CP II/III group, p=0.197. The aneurysm size remained stable in 9/44 (20%) patients; 5/30 (17%) patients in CP I group vs 4/14 (29%) patients in CP II/III group, p=0.741. The thoracic aneurysm increased size was seen in 1/44 (2%) patient. This patient was in CPII/III group.

CONCLUSION

CP technique using custom-made devices is technically feasible with a low mortality and morbidity, and a high rate of aortic remodeling. Both, the original design (CP I) and newer designs with a self-closing central sleeve (CP II and CP III) showed similar excellent outcomes.

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.

Candy-Plug Generation II for False Lumen Occlusion in Chronic Aortic Dissection: Feasibility and Early Results

Purpose: To present the early results of false lumen (FL) occlusion in chronic aortic dissection using the Candy-Plug generation II (CP II), which has a self-closing fabric channel that obviates the need for separate occlusion of its center. Materials and Methods: Fourteen consecutive patients (mean age 60±11 years; 10 men) with persistent FL backflow and aneurysm formation at the thoracic segment in chronic aortic dissection underwent thoracic endovascular aortic repair (TEVAR) with FL occlusion using the refined CP II. Primary endpoints were technical success (successful deployment) and clinical success (no FL backflow at the CP II level). Secondary endpoints included 30-day mortality and morbidity and aortic remodeling during follow-up. Results: Technical success was 100%. One patient required additional intraprocedural FL embolization at the CP II level due to persistent FL backflow on final angiography (clinical success 93%), though there was no flow through the CP II center. There were no intraprocedural complications. Immediate complete FL occlusion was achieved in 12 patients; the other 2 required reintervention. One had contrast enhancement in the distal FL proximal to the CP II and was treated with coil embolization. The other patient had persistent type I endoleak at the level of the left subclavian artery (LSA) and underwent left carotid–LSA bypass and proximal stent-graft extension. One patient died due to retrograde type A aortic dissection that was not related to CP II placement. Over a mean 8-month follow-up (range 3–12), 9 patients had computed tomography angiography; 8 patients had evidence of aortic remodeling, while 1 aneurysm sac was stable. Conclusion: The CP II reduces the number of procedural steps and offers good seal, with minimal morbidity and mortality and a high rate of aortic remodeling.

Impact of Renal Artery Stent-Graft Placement on Renal Function in Chronic Aortic Dissection

PURPOSE

To evaluate the effect of renal stent-graft placement on kidney function and size alternation in chronic aortic dissection.

MATERIALS AND METHODS

Twenty-five consecutive patients with chronic aortic dissection after thoracic endovascular aortic repair who underwent renal stent-graft placement between January 2015 and December 2016 were retrospectively reviewed. Forty-three patients with chronic aortic dissection who received thoracic endovascular aortic repair in the same period were reviewed as a control group for kidney volume comparison.

RESULTS

Twenty-five stent-grafts were deployed over 25 renal arteries. Overall renal function was assessed by the slope of the regression line constructed from the plots of creatinine clearance versus time within 2 years after the procedure (-0.2810 vs -0.3146 mL/min^-1/mo^-1, P = .868), kidney volume at 12 months (129.4 ± 40.9 vs 137.0 ± 44.2 cm², P = .193) and effective renal plasma flow at 6 months (106.3 ± 46.9 vs 124.4 ± 55.5 mL/min, P = .050) and was not significantly deteriorated. Seven treated patients (87.5%) with a renal artery supplied by a false lumen had a decrease in kidney volume, as did 14 patients (56%) in the control group (P = .206). Three patients with a dissected renal artery (75%) in the stent-graft group had an increase in kidney volume compared with 1 patient (11.1%) in the control group (P = .052).

CONCLUSIONS

Occlusion of the re-entry tear by a stent-graft in the renal artery remains a safe strategy to promote false lumen thrombosis. The stent-graft poses a potential risk of reducing the kidney volume in kidneys supplied by the false lumen but may provide a positive effect in kidney volume with a concomitant dissected renal artery in chronic aortic dissection.

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.

Techniques and outcomes of false lumen embolization in chronic type B aortic dissection

Endovascular strategies have been increasingly used for the treatment of chronic type B aortic dissection (cTBAD) offering better outcomes in terms of mortality and morbidity compared to open surgical repair. Aortic remodeling after standard TEVAR is less likely in cTBAD due to rigidity of the dissection membrane. Another limitation of endovascular therapy is continued retrograde false lumen perfusion with back-flow from distal entry tears. Treatment strategies in cTBAD should aim at false lumen thrombosis. There are many approaches to achieve this goal of false lumen thrombosis, but concepts as open surgery or fenestrated and branched endovascular repair are limited by either high technical and logistic demands to the surgeon or high rates of mortality and morbidity. False lumen embolization techniques offer less invasive treatment strategies with promising early results. The main strategies for false lumen embolization include the "cork in the bottle neck" technique, the Candy-Plug technique or the Knickerbocker-technique. This article describes technical aspects and early results of these new endovascular techniques of false lumen embolization in chronic aortic dissection.

Modified 'candy-plug' technique for chronic type B aortic dissection with aneurysmal dilatation: a case report

Background

The original ‘candy-plug’ technique has been reported to be beneficial for the treatment of residual perfused false lumen in patients with aortic dissection. However, this technique is also associated with several problems, such as narrowing of the true lumen and damage to the flap or vessel wall. Therefore, we modified the procedure to overcome these problems. Here we report a case in which the patient was successfully treated using the modified procedure.

Case presentation

A 59-year-old man presented with chronic type B aortic dissection with aneurysmal dilatation. The patient had undergone prosthetic graft replacement of the ascending aorta for acute type A aortic dissection 3 years previously and replacement of the descending aorta for residual type B aortic dissection with aneurysmal dilatation 1 year previously. After these procedures, the residual false lumen aneurysm of the distal descending aorta expanded to 57-mm in diameter. Endovascular stent grafting was successfully performed using the modified ‘candy-plug’ technique with relining of the true lumen and occlusion of the false lumen. The patient was discharged 10 days after the procedure. Follow-up imaging at 1 year showed a completely thrombosed false lumen aneurysm.

Conclusion

The modified ‘candy-plug’ technique is useful for treatment of residual type B aortic dissection with aneurysmal dilatation.

The Candy-Plug Technique: Technical Aspects and Early Results of a New Endovascular Method for False Lumen Occlusion in Chronic Aortic Dissection

PURPOSE

To describe the technical aspects and early results of the Candy-Plug technique for endovascular false lumen occlusion in chronic aortic dissection.

METHODS

A retrospective single-center study analyzing 18 consecutive patients (mean age 63 years, range 44-76; 16 men) with thoracic false lumen aneurysm in chronic aortic dissection. All patients underwent thoracic endovascular aortic repair with false lumen occlusion using the Candy-Plug technique. Primary endpoints consisted of technical success (successful deployment) and clinical success (no false lumen backflow). Secondary endpoints included 30-day mortality and morbidity as well as aortic remodeling during follow-up.

RESULTS

Technical success was 100%. Additional intraprocedural false lumen embolization at the Candy-Plug level was needed in 1 patient due to persisting false lumen backflow on the final angiogram (clinical success 94%). There were no intraprocedural complications. In the perioperative period, there were 3 minor complications: transient mild spinal cord ischemia, cervical hematoma after carotid-subclavian bypass, and a common femoral artery pseudoaneurysm. No deaths or reinterventions occurred. Complete distal false lumen occlusion was present on postoperative computed tomography in 15 patients, while 3 had minor contrast enhancement in the distal false lumen. Over a mean 9-month follow-up (range 0-26), 1 patient died due to rupture. Follow-up >6 months was available in 10 patients (mean 14.7 months, range 7-26): 7 patients showed aortic remodeling, while aneurysm size was stable in 3 patients.

CONCLUSION

The Candy-Plug technique is a feasible endovascular method to achieve false lumen occlusion and aortic remodeling in chronic aortic dissection. It is associated with low morbidity and mortality due to its minimal invasiveness.