non-A non-B Aortic Dissection Research Articles

An incidental finding of localized aortic arch dissection in a polytraumatized patient. A case report and state of the art of non-A non-B aortic dissection.

Non-A non-B aortic dissection is considered a rare nosological entity, included in the Stanford classification, representing a small percentage of the total aortic dissections that occur annually. Regarding this form, the literature reports a more complicated disease course compared to other types of dissection. We describe the case of a 76-year-old patient who accessed the triage section of an emergency department for a polytrauma picture and, after surgical treatment of a leg fracture, received a diagnosis of non-A non-B aortic dissection, "localized" to the arch and incidentally detected. The angio-computed tomography (CT) showed that the only intimal tear was located in the central portion of the aortic arch, with no exit tear. No signs of malperfusion or clinical symptoms related to the aortic finding were evident. The Aortic Team decided on a conservative approach, whereby the patient was started on medical therapy to control blood pressure in a monitored bed of a semi-intensive care unit. The persistent asymptomatic state, a condition of hemodynamic stability, and an unchanged angio-CT picture enabled discharge on day 7 and the assignment to a close follow-up.

Zone Zero Hybrid Repair of the Thoracic Rupture of a False Lumen in Non-A Non-B Aortic Dissection

Zone Zero Hybrid Repair of the Thoracic Rupture of a False Lumen in Non-A Non-B Aortic Dissection

Non-A non-B aortic dissection: just for cardiac surgeons? A systematic literature review on surgical and endovascular treatment

Non-A non-B aortic dissection: just for cardiac surgeons? A systematic literature review on surgical and endovascular treatment

Total aortic arch debranching with antegrade Thoracic Endovascular Aortic Repair (TEVAR) in acute non-A non-B aortic dissection

BackgroundThe surgical evaluation and management of non-A non-B aortic dissections, in the absence of ascending aortic involvement, remains a grey area. It is in these scenarios when thorough evaluation of patient/family history, clinical presentation, but also overall lifestyle, is of immense importance when determining an optimal intervention.Case presentationWe present a 38-year-old patient with a physically demanding lifestyle as a professional wrestler, uncontrolled hypertension due to history of medical non-adherence, and family history of aortic dissection who presented with acute non-A non-B aortic dissection. He was spared a total arch replacement by undergoing a hybrid approach of complete aortic debranching with antegrade Thoracic Endovascular Aortic Repair (TEVAR). The patient was able to benefit from reduced cardiopulmonary bypass (CPB) time, avoidance of aortic cross clamp, circulatory arrest, and hypothermic circulation.ConclusionsThis patient’s unique composition of a physically demanding lifestyle, personal history of medical non-adherence, family history of aortic dissection, and clinical presentation required a holistic approach to understanding an ideal intervention that would be best suited long-term. Due to this contextualization, the patient was able to be spared a total arch replacement, or suboptimal medical management, by instead undergoing a hybrid-approach with total aortic arch debranching with antegrade TEVAR.

Differences in In-Hospital and Follow-Up Outcomes Between Non-A Non-B Aortic Dissection and Type B Aortic Dissection Treated by Endovascular Based Treatment.

Non-A non-B aortic dissection (AD) is a rare and life-threatening medical emergency, and it has been controversial whether it should be managed as type B aortic dissection (TBAD). The study aims to compare in-hospital and follow-up outcomes between patients with non-A non-B AD and those with TBAD treated by endovascular based treatment (EBT). From January 2017 to December 2021, 96 consecutive patients with non-A non-B AD met the inclusion criteria and underwent EBT. Patients with TBAD were matched to patients with non-A non-B AD at a 1:1 ratio using propensity score matching analysis to correct for baseline confounding factors. The primary endpoint was all-cause mortality. Aortic-related events were defined as dissection-related death, aortic rupture, retrograde type A aortic dissection, reintervention, and type Ia endoleak. Patients with non-A non-B AD required more TEVAR-related adjunctive procedures compared to TBAD patients during EBT and they required a longer ICU length of stay (36.0 vs 24.0 hours, P < .05) as well as a longer hospitalization (8.0 vs 7.0 days, P < .05) after EBT. There was no statistical difference in overall survival after EBT for patients with TBAD and non-A non-B AD. However, compared to patients with TBAD, non-A non-B AD patients had a higher rate of reintervention and experienced more aortic-related late events during follow-up. Patients with non-A non-B acute AD who are treated with EBT do not have higher in-hospital or follow-up mortality rates compared to patients with type B AD. However, there is an increased risk of reintervention and aortic-related late events after the intervention during follow-up.

Total endovascular repair of an aortic arch using a triple-branched graft in acute non-A non-B aortic dissection.

Total endovascular repair of an aortic arch using a triple-branched graft in acute non-A non-B aortic dissection.

Current knowledge and contemporary management of non-A non-B aortic dissections

Non-A non-B aortic dissection (AAD) is an infrequently documented condition, comprising of only a small proportion of all AADs. The unique anatomy of the aortic arch and the failure of the existing classifications to adequately define individuals with non-A non-B AAD, have led to an ongoing controversy around the topic. It seems that the clinical progression of acute non-A non-B AAD diverges from the typical type A and B dissections, frequently leading to serious complications and thus mandating early intervention. Currently, the available treatment methods in the surgical armamentarium are conventional open, endovascular techniques and combined hybrid methods. The optimum approach is tailored in every individual case and may be determined by the dissection's location, extent, the aortic diameter, the associated complications and the patient's status. The management of non-A non-B dissections still remains challenging and a unanimous consensus defining the gold standard treatment has yet to be reached. In an attempt to provide further insight into this perplexing entity, we performed a minireview of the literature, aiming to elucidate the epidemiology, clinical course and the optimal treatment modality.

Brain Protection in Patients with Aortic Dissection and Coronary Artery Disease

The aim. To compare the effectiveness of methods of protecting the brain and visceral organs during operations for aortic aneurysms combined with coronary artery lesions.&#x0D; Materials and methods. In the period from 2012 to 2020, 23 patients with Stanford type A and non-A non-B aortic dissection with damage to the coronary arteries were operated at the National Amosov Institute of Cardiovascular Surgery of the NAMS of Ukraine using the brain protection techniques. Out of 23 surgical interventions, 16 were performed for Stanford type A acute aortic dissection, 3 for Stanford type A chronic aortic dissection, 1 for Stanford type A subacute aortic dissection, and 3 for Stanford non-A non-B aortic dissection. The main causes of aortic dissection were hypertension (16 patients), Marfan syndrome (3 patients), bicuspid aortic valve (4 patients).&#x0D; Results. The most threatening postoperative complication in this group of patients is neurological damage, which was observed in 4 (17%) patients after surgery, with gradual recovery of brain function. Also, the complications observed were respiratory failure in 3 (13%) patients, which required long-term artificial ventilation (more than 72 hours), and multiple organ failure in 1 (4.3%) patient, which caused a fatal outcome.Complications such as kidney and liver failure were not observed (most likely due to the small sample size). Heart failure was not noted as well. Hospital mortality was 4.3% (1 fatal case). In our study, among the entire group of operated patients, symptoms of neurological damage occurred in 4 (17.4%) patients, hemorrhagic stroke was present in 1 (4.3%) patient with a complicated medical history, 2 (8.6%) patients had hemiparesis and in 1 case (4.3%) there were cognitive disorders.&#x0D; Conclusions. Comparing brain protection techniques, taking into account the prolongation of aortic clamping time due to coronary artery shunting compared to isolated aortic dissection, it can be concluded that longer duration of selective brain perfusion (retrograde or antegrade) or duration of circulatory arrest more often lead to postoperative complications, namely neurological lesions.&#x0D; On the other hand, the small number of observations does not make it possible to fully assess the impact of each of the techniques. Further follow-up with a larger sample will provide opportunities for a more complete evaluation of brain protection techniques in operations for dissecting aortic aneurysms and coronary artery lesions.

Management and Outcomes of Non-A Non-B Aortic Dissection

The results of best medical treatment (BMT), endovascular based treatment (EBT), and total arch replacement (TAR) with frozen elephant trunk (FET) treatment in a single centre experience were reported in non-A non-B aortic dissection patients. From January 2016 to May 2020, 215 consecutive patients with acute or subacute non-A non-B aortic dissection were enrolled. The primary endpoints were all cause death. Secondary endpoints included follow up adverse aortic event (AE), a composite of the outcomes of dissection related death, rupture, retrograde type A aortic dissection, stent graft induced new entry tear, secondary endoleak, and follow up re-intervention. Kaplan-Meier curves were used to evaluate associations between different treatments and outcomes. Among the 215 dissection patients, 127 (59.1%) received EBT, 42 (19.5%) received TAR+ FET, and the remaining 46 (21.4%) received BMT. Thirty day mortality was higher in patients receiving TAR+ FET (7.1%) than in those treated with EBT (1.6%) or BMT (2.2%) (p= .12). However, after a median follow up of 39.1 (27.0 - 50.7) months, no additional death was recorded in the TAR+ FET group, while nine (7.3%) patients died in the EBT group and 14 (31.8%) died in the BMT group (p < .001). Specifically, EBT and TAR+ FET showed no significant difference in midterm mortality rate, follow up AE, and re-intervention for complicated or uncomplicated dissection patients involving zone 2. For patients with uncomplicated non-A non-B aortic dissection involving zone 2, EBT could profoundly decrease the mortality rate, follow up AE and re-intervention when compared with BMT (p < .010 for all), although this difference was not statistically significant between TAR+ FET and BMT. No statistical comparison was performed in patients with zone 1 involvement because of the limited number of patients. It was demonstrated that EBT or TAR+ FET might be a viable strategy for non-A non-B aortic dissection patients.

False lumen/true lumen wall pressure ratio is increased in acute non-A non-B aortic dissection

OBJECTIVESWe aimed to determine whether non-A non-B aortic dissection (AD) differs in morphologic and haemodynamic properties from type B AD.METHODSWe simulated and compared haemodynamics of patients with acute type B or acute non-A non-B AD by means of computational fluid dynamics. Wall pressure and wall shear stress (WSS) in both the true lumen (TL) and false lumen (FL) at early, mid- and late systole were evaluated. Morphology, WSS and the FL/TL wall pressure ratio were compared between groups.RESULTSNineteen patients (type B, n = 7; non-A non-B, n = 12) were included. The median age (51 [46, 67] vs 53 [50, 63] years; P = 0.71) and a complicated course (14% vs 33%; P = 0.6) did not differ between the type B group and the non-A non-B group. However, the median entry tear width was increased in the non-A non-B group (9.7 [7.3, 12.7] vs 16.3 [11.9, 24.9] mm; P = 0.010). Streamlines showed, in patients with non-A non-B AD, blood from the TL flowed into the FL via the entry tear. Prevalence of a FL/TL wall pressure ratio >1.0 (type B versus non-A non-B) at early, mid- and late systole was 57% vs 83% (P = 0.31), 43% vs 83% (P = 0.13) and 57% vs 75% (P = 0.62), respectively. WSS did not differ between the groups.CONCLUSIONSThe increased FL/TL wall pressure ratio observed during systole in non-A non-B AD may beget a complicated presentation.

Initial Study of the Extended STABILISE Technique for Complete Remodeling in Aortic Dissection

Thoracic endovascular aortic repair (TEVAR) is the standard treatment for acute complicated type B aortic dissection (TBAD). However, long-term results reveal that TEVAR does not achieve a complete aortic remodeling and poses a risk of aneurysmal aortic degeneration. Distal re-entry treatment at the abdominal level seems to be necessary to obtain a complete remodeling in TBAD. Moreover, it is necessary to treat the aortoiliac bifurcation in patients with persistent true lumen collapse or limb ischemia. Between January 2018 and October 2019, 11 patients with acute or sub-acute complicated TBAD or non-A non-B aortic dissection were treated in our institution in an endovascular fashion. We performed the stent-assisted, balloon-induced intimal disruption and relamination in aortic dissection repair (STABILISE) technique in all cases, but 2 cases required complementary treatment of the aortoiliac bifurcation with a bifurcated AFX endograft system for limb ischemia due to true lumen collapse. Technical success was obtained in all patients. No procedural complications occurred. No postoperative deaths, stroke, paraplegia, mesenteric, or renal ischemia were observed, and no secondary intervention was necessary. Satisfactory aortic re-modeling was obtained after the follow-up periods with a 57.5% mean true lumen expansion. Our initial experience using the extended STABILISE (e-STABILISE) technique using a bifurcated AFX endograft did not result in any postoperative mortality or complications. Without additional data, this technique should be reserved for specific patients who require revascularization of the aortoiliac bifurcation.

The Results of the Use of the Technique of Switching the Vessels of the Aortic Arch in the Formation of the Avascular Zone of Stent-Graft Fixation in the Hybrid Treatment of Thoracic Aortic Aneurysms

Thoracic and aortic aneurysms, including Stanford type B and neither A nor B aneurysms, are a complex problem for cardiac surgery. For a long time, the treatment of this pathology was carried out through the open method, which was associated with high hospital mortality. Hybrid and endovascular treatment have significantly reduced the number of complications and improved in-hospital mortality, although such methods are associated with specific difficulties, the study and elimination of which is an urgent issue at the present stage of cardiac surgery.&#x0D; The aim. To analyze the immediate and first long-term results of treatment of type B and non-A non-B aortic dissection through the hybrid method with the formation of avascular zone of proximal fixation of the stent-graft in the aortic arch, i.e. “landing zone”.&#x0D; Materials and methods. For the period from January 1, 2016 to December 31, 2019 at the National Amosov Institute of Cardiovascular Surgery of the NAMS of Ukraine 122 patients underwent surgical treatment for type B and non-A nonB aortic dissection, of whom 57 (46.7%) patients underwent hybrid intervention involving the formation of a “landing zone”, i.e. an avascular section of the aortic arch to fix the stent-graft. Stent-graft was implanted in Z0 in 5 (8.8%) cases, in Z1 in 24 (42.1%) cases, and in Z2 in 28 (49.1%) cases. The stent-grafts used were Lifetech Ankura (41 cases), Relay (12 cases), and Medtronic Valiant (4 cases). The main causes of pathology were type B acute aortic aneurysm (11 [19%]), type B subacute aortic aneurysm (4 [7%]), type B chronic aortic aneurysm (30 [53%]), penetrating aortic ulcer (1 [2%]), primary parietal thrombosis of the aortic lumen (1 [2%]), postcoarctation aortic aneurysm (8 [14%]), thoracic aortic aneurysm (3 [5%]).&#x0D; Results. The total number of complications was 11 (19% of cases). Among the types of operations, the number of complications was evenly distributed, 5/28 (18%) were observed in partial debranching, 5/27 (19%) in subtotal debranching and 1/2 (50%) in total debranching. Hospital mortality was 3/122 (5.3%).&#x0D; Conclusions. The described methods of treatment of aneurysms of the arch and descending aorta have real prospects for development due to minimal invasiveness, reduction of the duration of surgery and time spent in the clinic, and significantly lower in-hospital mortality compared to traditional “open” surgery.

Non-A non-B acute aortic dissection with entry tear in the aortic arch.

OBJECTIVESOur aim was to describe the outcomes of the latest treatment options of acute non-A non-B aortic dissection involving an entry tear in the aortic arch.METHODSIncluded were patients who presented between January 2001 and February 2020 with a non-A non-B aortic dissection involving the aortic arch but not the ascending aorta and with the most proximal entry tear located within the aortic arch between the innominate and left subclavian artery. Clinical data and operative details were retrieved from medical histories and surgical protocols. Preoperative, postoperative and follow-up computed tomography angiography scans were analysed.RESULTSWe analysed a total of 39 patients [median age 62 (52; 67) years, men 76.9%] with non-A non-B arch entry aortic dissections type. They underwent 15 thoracic endovascular aortic repairs, 20 frozen elephant trunk implantations, 1 hybrid arch replacement, or 1 conventional arch replacement. Two patients were managed conservatively. Twelve (31%) patients underwent emergent intervention, 12 (31%) were treated invasively within 2 weeks. Another 2 (5%) and 9 (23%) patients were treated 2 and 4 weeks after dissection occurred, respectively. Six (15%) patients presented with an impending aortic rupture, while 19 (49%) had at least one malperfused organ. Four patients (27%) died after thoracic endovascular aortic repair; the 30-day mortality following frozen elephant trunk was 0%.CONCLUSIONSNon-A non-B acute aortic dissection reveals a frequently complicated course requiring emergency intervention. The majority of patients required aortic arch repair within the first 2 weeks. Total arch replacement with the frozen elephant trunk technique seems to be low procedural mortality, and may become the treatment of choice in arch entry non-A non-B aortic dissection.

Triple-Branched Stent Graft Implantation for Acute Non-A–non-B Aortic Dissection

BackgroundThe optimal treatment for acute non-A–non-B aortic dissection remains controversial. Triple-branched stent graft (TBSG) implantation has been used to treat acute type A aortic dissection. This study aimed to evaluate the safety and efficacy of TBSG as a treatment for acute non-A–non-B aortic dissection. MethodsFifty patients with non-A–non-B dissection received TBSG implantation in our center between January 2014 and December 2019. Early mortality, morbidity, and dissected aorta remodeling during follow-up were calculated. ResultsThere were no deaths in-hospital or within 30 days. Postoperative complications included pneumonia (n = 12), acute kidney injury (n = 6; preoperative renal malperfusion, n = 4), transient cerebral injury (n = 6; preoperative cerebral malperfusion, n = 4), pleural effusion (n = 4), and pericardial effusion (n = 2). During follow-up, 1 patient experienced a stroke, and 2 patients required secondary interventional therapy for residual dissection below the level of the TBSG. All implanted TBSGs had good positioning, and all sidearm stent graft grafts were fully patent. No retrograde aortic dissection or type I endoleak was detected. ConclusionsTBSG implantation for acute non-A–non-B aortic dissection had a low incidence of mortality and morbidity, featuring good remodeling of the dissected aortic wall during follow-up. The early outcomes of this technique were satisfactory.

Early and Long-Term Follow-Up for Chronic Type B and Type Non-A Non-B Aortic Dissection Using the Frozen Elephant Trunk Technique.

Background: This study aimed to evaluate the early and long-term outcomes of a single center using a frozen elephant trunk (FET) procedure for chronic type B or non-A non-B aortic dissection.Methods: From February 2009 to December 2019, 79 patients diagnosed with chronic type B or non-A non-B aortic dissection who underwent the FET procedure were included in the present study. We analyzed operation mortality and early and long-term outcomes, including complications, survival and interventions.Results: The operation mortality rate was 5.1% (4/79). Spinal cord injury occurred in 3.8% (3/79), stroke in 2.5% (2/79), and acute renal failure in 5.1% (4/79). The median follow-up time was 53 months. The overall survival rates were 96.2, 92.3, 88.0, 79.8, and 76.2% at 1/2, 1, 3, 5 and 7 years, respectively. Moreover, 79.3% of patients did not require distal aortic reintervention at 7 years. The overall survival in the subacute group was superior to that in the chronic group (P = 0.047).Conclusion: The FET technique is a safe and feasible approach for treating chronic type B and non-A non-B aortic dissection in patients who have contraindications for primary endovascular aortic repair. The technique combines the advantages of both open surgical repair and endovascular intervention, providing comparable early and long-term follow-up outcomes and freedom from reintervention.

Non-A non-B aortic dissection: A literature review.

Non-A non-B aortic dissections are an infrequent occurrence and represent a small proportion of aortic dissections. Treating this life-threatening medical emergency often requires surgeons to undertake some one of the most challenging surgical or endovascular cases in medicine. This literature review aims to define and classify non-A non-B dissections, describe their epidemiology as well as their pathology. This review also aims to discuss the range of surgical techniques employed in their treatment and management and to investigate the patient outcomes associated with each technique.

The Frozen Elephant Trunk Technique for the Treatment of Type B and Type Non-A Non-B Aortic Dissection

To evaluate outcomes of patients with acute complicated or chronic Type B or non-A non-B aortic dissection who underwent the frozen elephant trunk (FET) technique. Between April 2013 and July 2019, 41 patients presenting with acute complicated (n=29) or chronic (n=12) descending thoracic aortic dissection were treated by the FET technique, which was the treatment of choice when supra-aortic vessel transposition would not suffice to create a satisfactory proximal landing zone for endovascular aortic repair, when a concomitant ascending or arch aneurysm was present, or in patients with connective tissue diseases. One patient (2%) died intra-operatively secondary to an aortic rupture in dwnstream aortic segments. No post-operative deaths occurred. Four patients (10%) suffered a non-disabling posto-operative stroke and were discharged with no clinical symptoms (modified Rankin Scale [mRS] 0, n=1), no significant disability (mRS 1, n=2), or with slight disability (mRS 2, n=1). No spinal cord ischaemia was observed. The primary entry tear was either surgically resected or excluded from circulation in all patients. During follow up, one patient (2%) died after two years (not aorta related) and 16 patients (39%) underwent an aortic re-intervention after 7.7 [interquartile range 0.7, 15.8] months (endovascular aortic repair: n=14; open thoraco-abdominal aortic replacement: n=1, hybrid approach: n=1). The FET technique is an effective treatment option for acute complicated and chronic Type B or non-A non-B aortic dissection in patients in whom primary endovascular aortic repair is non-feasible. While the post-operative outcome is acceptable with a relatively low incidence of non-disabling strokes, this study also underlines the considerable need for aortic re-interventions. Continuous follow up of all patients undergoing the FET procedure is essential.

Early outcomes with a hybrid technique for repair of a non-A non-B aortic dissection

ObjectiveThis study reports the early outcomes of patients with acute non-A non-B aortic dissection that involved the aortic arch but not the ascending aorta. MethodsFrom January 2013 to December 2018, 825 patients presented with aortic dissection. Of these, 28 patients with non-A non-B dissection (classified as dissection extending into the aortic arch with entry between the left common carotid artery and the left subclavian arteries) underwent a novel hybrid surgery. Self modified stent-grafts (Micropart Corp, Shanghai, China) were implanted via median sternotomy. Clinical presentation, postoperative data, and early outcomes were recorded. ResultsAll patients underwent an emergency operation. There were no in-hospital mortalities, reexplorations for hemorrhage, reports of paraplegia, cerebral infarctions, endoleaks, or left subclavian artery occlusions. No blood products were required during or after the operations. During the early follow-up at 39.12 ± 15.04 months (6.0-74.0 months), 1 patient was lost to follow-up, and 1 patient died suddenly. Computed tomography angiography showed false lumen patency persisted in the aortic arch and descending aorta without any symptoms. The 6-month computed tomography angiography showed significantly smaller distal aortic arch diameters (31.94 ± 6.95 mm) and descending aorta diameters (34.84 ± 4.15 mm) than measured preoperatively (36.76 ± 4.15 mm and 37.31 ± 4.7 mm, respectively). No paraplegia, cerebral infarction, upper limb ischemia, or left subclavian artery ischemia events were reported. ConclusionsOur inclusion aortic arch technique is a safe, effective, and simple treatment for non-A non-B aortic dissections that can avoid endoleaks, requires no blood products, and has satisfactory early outcomes.

Aortic dissection reconsidered: type, entry site, malperfusion classification adding clarity and enabling outcome prediction.

Aortic dissection is complex. Imaging and treatment modalities are evolving, demanding a more differentiated but pragmatic dissection classification. Our goal was to provide a new practical classification system including Type of dissection, location of the tear of the primary Entry and Malperfusion (TEM). We extended the Stanford dissection classification (A and B) by adding non-A non-B aortic dissection, the location of the primary entry tear (E) and malperfusion (M). A 0 was added if the primary entry tear was not visible; 1, if it was in the ascending aorta; 2, if it was in the arch; and 3, if it was in the descending aorta (E0, E1, E2, E3). We added 0 if malperfusion was absent; 1, if coronary arteries; 2, if supra-aortic vessels; and 3, if visceral/renal and/or a lower extremity was affected (M0, M1, M2, M3). Plus (+) was added if malperfusion was clinically present and minus (-) if it was a radiological finding. The new classification system was analysed in 357 patients retrospectively; distribution was 59%, 31% and 10% for A, B and non-A non-B dissections. The in-hospital mortality rate was 16%, 5% and 8% (P = 0.01). Postoperative stroke occurred in 14%, 1% and 3% (P < 0.001). The in-hospital mortality rate was 22%, 14%, 40% and 0% in A E0, E1, E2 and E3 (P = 0.023), respectively. Two years after the onset of dissection, the lowest survival rate was observed in A, followed by non-A non-B and B (83 ± 3% vs 88 ± 6% vs 93 ± 3%; P = 0.019). The new practical TEM aortic dissection classification system adds clarity regarding the extent of the disease process, enhances awareness of the disease mechanism, aids in decision-making regarding the extent of repair and helps in anticipating outcome.

Non-A non-B aortic dissections: are we still in uncharted waters?

Non-A non-B aortic dissections: are we still in uncharted waters?