Partial Thrombosis Of False Lumen Research Articles

False lumen hemodynamics and partial thrombosis in chronic aortic dissection of the descending aorta.

Partial thrombosis of the false lumen (FL) in patients with chronic aortic dissection (AD) of the descending aorta has been associated with poor outcomes. Meanwhile, the fluid dynamic and biomechanical characteristics associated with partial thrombosis remain to be elucidated. This retrospective, single-center study tested the association between FL fluid dynamics and biomechanics and the presence and extent of FL thrombus. Patients with chronic non-thrombosed or partially thrombosed FLs in the descending aorta after an aortic dissection underwent computed tomography angiography, cardiovascular magnetic resonance (CMR) angiography, and a 4D flow CMR study. A comprehensive quantitative analysis was performed to test the association between FL thrombus presence and extent (percentage of FL with thrombus) and FL anatomy (diameter, entry tear location and size), fluid dynamics (inflow, rotational flow, wall shear stress, kinetic energy, and flow acceleration and stasis), and biomechanics (pulse wave velocity). Sixty-eight patients were included. In multivariate logistic regression FL kinetic energy (p = 0.038) discriminated the 33 patients with partial FL thrombosis from the 35 patients with no thrombosis. Similarly, in separated multivariate linear correlations kinetic energy (p = 0.006) and FL inflow (p = 0.002) were independently related to the extent of the thrombus. FL vortexes, flow acceleration and stasis, wall shear stress, and pulse wave velocity showed limited associations with thrombus presence and extent. In patients with chronic descending aorta dissection, false lumen kinetic energy is related to the presence and extent of false lumen thrombus. In patients with chronic aortic dissection of the descending aorta, false lumen hemodynamic parameters are closely linked with the presence and extent of false lumen thrombosis, and these non-invasive measures might be important in patient management. • Partial false lumen thrombosis has been associated with aortic growth in patients with chronic descending aortic dissection; therefore, the identification of prothrombotic flow conditions is desirable. • The presence of partial false lumen thrombosis as well as its extent was related with false lumen kinetic energy. • The assessment of false lumen hemodynamics may be important in the management of patients with chronic aortic dissection of the descending aorta.

Uncomplicated Type B Aortic Dissection: Challenges in Diagnosis and Categorization

Acute type B aortic dissection (TBAD) is a rare disease that is likely under-diagnosed in the UK. As a progressive, dynamic clinical entity, many patients initially diagnosed with uncomplicated TBAD deteriorate, developing end-organ malperfusion and aortic rupture (complicated TBAD). An evaluation of the binary approach to the diagnosis and categorisation of TBAD is needed. A narrative review of the risk factors predisposing patients to progression from unTBAD to coTBAD was undertaken. Key high-risk features predispose the development of complicated TBAD, such as maximal aortic diameter > 40 mm and partial false lumen thrombosis. An appreciation of the factors that predispose to complicated TBAD would aid clinical decision-making surrounding TBAD.

Shear-driven modelling of thrombus formation in type B aortic dissection.

Background: Type B aortic dissection (TBAD) is a dangerous pathological condition with a high mortality rate. TBAD is initiated by an intimal tear that allows blood to flow between the aortic wall layers, causing them to separate. As a result, alongside the original aorta (true lumen), a false lumen (FL) develops. TBAD compromises the whole cardiovascular system, in the worst case resulting in complete aortic rupture. Clinical studies have shown that dilation and rupture of the FL are related to the failure of the FL to thrombose. Complete FL thrombosis has been found to improve the clinical outcomes of patients with chronic TBAD and is the desired outcome of any treatment. Partial FL thrombosis has been associated with late dissection-related deaths and the requirement for re-intervention, thus the level of FL thrombosis is dominant in classifying the risk of TBAD patients. Therefore, it is important to investigate and understand under which conditions complete thrombosis of the FL occurs. Method: Local FL hemodynamics play an essential role in thrombus formation and growth. In this study, we developed a simplified phenomenological model to predict FL thrombosis in TBAD under physiological flow conditions. Based on an existing shear-driven thrombosis model, a comprehensive model reduction study was performed to improve computational efficiency. The reduced model has been implemented in Ansys CFX and applied to a TBAD case following thoracic endovascular aortic repair (TEVAR) to test the model. Predicted thrombus formation based on post-TEVAR geometry at 1-month was compared to actual thrombus formation observed on a 3-year follow-up CT scan. Results: The predicted FL status is in excellent agreement with the 3-year follow-up scan, both in terms of thrombus location and total volume, thus validating the new model. The computational cost of the new model is significantly lower than the previous thrombus model, with an approximate 65% reduction in computational time. Such improvement means the new model is a significant step towards clinical applicability. Conclusion: The thrombosis model developed in this study is accurate and efficient at predicting FL thrombosis based on patient-specific data, and may assist clinicians in choosing individualized treatments in the future.

False Lumen Flow Assessment by Magnetic Resonance Imaging and Long-Term Outcomes in Uncomplicated Aortic Dissection

BackgroundDespite the absence of clinical complications after an acute aortic dissection (AD) with persistent patent false lumen (FL), a high risk for clinical events may persist. ObjectivesThe aim of this study was to assess the natural evolution of noncomplicated AD and ascertain whether different FL flow patterns by magnetic resonance imaging (MRI) have independent prognostic value for AD-related events beyond established morphologic parameters. MethodsOne hundred thirty-one consecutive patients, 78 with surgically treated type A dissections and 53 with medically treated type B dissections, were followed up prospectively after acute AD with persistent patent FL in the descending aorta. Maximum aortic diameter, true lumen compression, entry tear, and partial FL thrombosis by computed tomography were assessed. Systolic antegrade true lumen and FL flow volumes and diastolic antegrade and retrograde flows were analyzed by MRI during the first year after AD. ResultsAfter a median follow-up period of 8.0 years (IQR: 4.6-10.9 years), 43 patients presented aorta-related events (25 died and 18 required endovascular treatment). FL systolic antegrade flow ≥30% with respect to total systolic antegrade flow and retrograde diastolic flow ≥80% with respect to total diastolic FL flow were predictors of aortic events. In multivariate analysis, aortic diameter >45 mm (HR: 2.91), type B dissection (HR: 2.44), and MRI flow pattern (HR: 16.87) were independent predictors of AD-related events. ConclusionsHigh systolic antegrade flow volume in the FL with significant diastolic retrograde flow assessed by MRI and aortic diameter >45 mm identify patients with higher risk for complications in whom more aggressive management would be indicated.

False Lumen Thrombosis and Pressure Predicts Outcome in Patients with Acute Type B Aortic Dissection

Introduction: Owing to the uncertainty around how best to manage patients with type B aortic dissection (TBAD), improved risk stratification is a key priority. Partial false lumen thrombus morphology has been demonstrated to predict complications; however, partial thrombosis is poorly defined and has not been evaluated in detail. We hypothesised that partial false lumen thrombosis is a marker of false lumen pressure and that false lumen pressure is related to clinical events.

Differences in the Area of Proximal and Distal Entry Tears at CT Angiography Predict Long-term Clinical Outcomes in Aortic Dissection.

To identify entry tear variables that are related to adverse clinical events by using CT angiography (CTA) performed during the subacute phase of aortic dissection. In this prospective study conducted from January 2000 to December 2013, participants with an aortic dissection with a patent false lumen and no comorbidities underwent CTA during the subacute phase. Participants were followed up for a survival analysis to assess the time to an adverse aortic event (AAE). The maximum aortic diameter (MAD), proximal and distal tear areas and difference between these areas, and partial false-lumen thrombosis were assessed by using Cox regression for adverse events. Seventy-two participants (mean age, 55 years ± 12 [standard deviation]; 55 men) were evaluated: 47 were surgically treated (type A aortic dissection) and 25 were medically treated (type B aortic dissection). Twenty-two participants had an AAE manifest during follow-up (9.22 years ± 5.78): There were 18 elective surgeries for aneurysmal degeneration, two emergent surgeries for acute aortic syndrome, and two aortic condition-related deaths. A categorical model composed of genetic aortic disease (GAD) (hazard ratio [HR], 3.4 [95% CI: 1.2, 9.9]; P = .02), MAD greater than 45 mm (HR, 6.1 [95% CI: 2.4, 15.8]; P < .001), and tear dominance (HR, 5.2 [95% CI: 2.1, 13]; P < .001), defined as an absolute tear area difference of greater than 1.2 cm2, was used to stratify participants into three risk groups: low, without any risk factors (57% [41 of 72] and 7% [three of 41] had events); intermediate, with one risk factor (31% [22 of 72] and 50% [11 of 22] had events); and high, with two or more risk factors (13% [nine of 72] and 89% [eight of nine] had events; log rank P < .001). Tear dominance demonstrated at CTA performed in the subacute phase of aortic dissection was related to long-term adverse events. Participants without GAD, dominant tears, or MAD greater than 45 mm had conditions that were safely managed with optimal medical treatment and imaging follow-up.Keywords: CT Angiography, Vascular, Aorta, Dissection Supplemental material is available for this article. © RSNA, 2021See also commentary by Fleischmann and Burris in this issue.

Early Experience With a Novel Dissection-Specific Stent-Graft to Prevent Distal Stent-Graft-Induced New Entry Tears After Thoracic Endovascular Repair of Chronic Type B Aortic Dissections

The aim was to report short and mid-term outcomes of a novel, investigational, dissection-specific stent-graft (DSSG), specifically designed to address the features of chronic type B aortic dissection (CTBAD) and reduce the risk of distal stent-graft-induced new entry tears (dSINE). A retrospective single center cohort study of all patients undergoing TEVAR with the DSSG for CTBAD from January 1, 2017 to January 31, 2020. The DSSG, which is a modified stent-graft based on the Cook Zenith Alpha Thoracic platform, has no proximal barbs, and a customized longer body length with substantial taper. The second and third distal Z-stents are sited internally to avoid any contact of the metal skeleton with the dissection membrane and have reduced radial force, while the most distal stent was removed creating a distal 30 mm unsupported Dacron graft. Sixteen patients (13 males, 3 females) with a median age of 66 years (range 31-79 years) underwent elective TEVAR of CTBAD using the DSSG. Six patients (38%) had an underlying connective tissue disorder. The median tapering was 10 mm (range 4 mm-21 mm) and median length 270 mm (range 210-380 mm). Technical success was achieved in all but one case (96%). One patient died within 30 days, due to retrograde type A dissection with cardiac tamponade. The 30-day rate of stroke, spinal cord ischemia, and re-interventions was 0%. After median imaging follow-up time of 17 months (range 1-31 months), one patient developed a dSINE 4 months after the index procedure. After median survival follow-up of 23 months (range 2-35 months), one late death occurred due to traumatic brain injury, while no aortic-related death occurred during follow-up. Complete false lumen (FL) thrombosis was achieved in 9 patients while the remaining 6 showed partial FL thrombosis. No instances of diameter increase at the level oftreated aortic segment were noted with serial measurements showing either stable (n = 7) or decreased (n = 8) maximal transverse diameter. Use of a novel DSSG with low radial force for TEVAR in the setting of CTBAD is safe and feasible. This early real-world experience shows promising mid-term effectiveness with low rates of dSINE or unplanned re-interventions and satisfactory aortic remodeling during follow-up. Longer follow-up is needed, however, before any firm conclusions can be drawn.

Sex-Based Aortic Dissection Outcomes From the International Registry of Acute Aortic Dissection

BackgroundWorse outcomes have been reported for women with type A acute aortic dissection (TAAD). We sought to determine sex-specific operative approaches and outcomes for TAAD in the current era. MethodsThe Interventional Cohort (IVC) of the International Registry of Acute Aortic Dissection (IRAD) database was queried to explore sex differences in presentation, operative approach, and outcomes. Multivariable logistic regression was performed to identify adjusted outcomes in relation to sex. ResultsWomen constituted approximately one-third (34.3%) of the 2823 patients and were significantly older than men (65.4 vs 58.6 years, P < .001). Women were more likely to present with intramural hematoma, periaortic hematoma, or complete or partial false lumen thrombosis (all P < .05) and more commonly had hypotension or coma (P = .001). Men underwent a greater proportion of Bentall, complete arch, and elephant trunk procedures (all P < .01). In-hospital mortality during the study period was higher in women (16.7% vs 13.8%, P = .039). After adjustment, female sex trended towards higher in-hospital mortality overall (odds ratio, 1.40; P = .053) but not in the last decade of enrollment (odds ratio, 0.93; P = .807). Five-year mortality and reintervention rates were not significantly different between the sexes. ConclusionsIn-hospital mortality remains higher among women with TAAD but demonstrates improvement in the last decade. Significant differences in presentation were noted in women, including older age, distinct imaging findings, and greater evidence of malperfusion. Although no distinctions in 5-year mortality or reintervention were observed, a tailored surgical approach should be considered to reduce sex disparities in early mortality rates for TAAD.

Flow density of computed tomography aortography for predicting early unfavorable aortic remodeling after TEVAR in type IIIb aortic dissection

ObjectivePatients diagnosed of DeBakey type III aortic dissection with partial thrombosis of false lumen (FL) have a higher mortality rate. However, IIIb dissections with full patent FL tend to exhibit a partially thrombosed FL quickly after thoracic endovascular aortic repair (TEVAR); thus, we investigated survival and aortic remodeling in this population. MethodsWe reviewed computed tomography aortograms (CTAs) of 123 patients with TEVAR-treated IIIb aortic dissections from July 2006 to June 2015; contrast density of CTAs represented intraluminal flow. Patients were selected to fit in 2 groups of FL in term of FL contrast density: low flow (LF) group (non-opacification in the midway of FL) and high flow (HF) group (full patent FL). ResultsSurgical mortality was 10.3% in the HF group and 4.5% in the LF group (n = 61; LF = 22; HF = 39). 3 patients in the HF group suffered from lethal aortic rupture in 10 days postoperatively. The HF group showed significant increase in maximal diameter, and had larger thoracic (+4.00 ± 2.68 vs −1.16 ± 3.42 mm, P < .001) aortic diameter expansion from preoperation to one week postoperation. Both groups exhibited significant favorable thoracic TL expansion and maximal aortic diameter shrinkage in postoperative one week to one year. However, HF group displayed less thoracic aortic FL regression (−70.9 ± 83.5 vs −113.9 ± 95.0 cm3, P = .1) and TL expansion (+14.5 ± 27.2 vs +36.8 ± 28.3 cm3, P = .008) when compared to LF group. ConclusionsPreoperative HF in the FL has an unfavorable effect on thoracic aortic diameter in one week post-TEVAR. This might increase the risk of aortic rupture.

Predictors for outcome in type A aortic dissection: A focus on false lumen

BackgroundAcute type A aortic dissection (AAD) is a life-threatening emergency in cardiac surgery, with high in-hospital (22%) and long-term morbidity and mortality rates. MethodsData from 134 patients were collected from anamnesis and computed tomography before and after aortic surgery. Data were analyzed using IBM SPSS v23. ResultsWe found that male patients had better survival than the female (p<0.01) and that age is associated with increased perioperative death (p<0.001). Similarly, patients admitted in shock (p<0.001) and undergoing longer extracorporeal circulation (p<0.05) were associated with lower survival. We observed that patients admitted with partial thrombosis of false lumen had increased survival compared to those presenting a patent lumen (p<0.001). Also, we compared the mortality of the different surgical procedures and found that no intervention had a significant association with increased survival (p>0.05).Among survived patients, we found that an increased pre-operative ascending aorta diameter is associated with the establishment of a chronic partial thrombosis (54.2±4.6 vs 50.5±7.0mm, p<0.05). Moreover, increased pre-operative descending aorta diameter is associated with a longer complete thrombosis time (29.2±6.1 vs 37.2±6.9mm, p<0.05). ConclusionsWe found that, in our experience, there is no significant difference between the most commonly used surgical procedures. However, we found that age, gender, shock, pre-operative lumen patency and CEC time are important predictors of survival. Moreover, we found that pre-operative aortic diameters are dramatically relevant to determine the time for a complete thrombosis of the false lumen.

Surgical Decision Making in Uncomplicated Type B Aortic Dissection: A Survey of Australian/New Zealand and European Surgeons

There is controversy about the role of pre-emptive thoracic endovascular aortic repair (TEVAR) in uncomplicated type B aortic dissection (TBAD). The aim was to understand expert opinions and the factors influencing decision making. In 2018, surgeons from Australia/New Zealand (ANZ) and Europe (EUR) were contacted to participate in an online survey which comprised questions about preferences for pre-emptive TEVAR, followed by five case scenarios, and two ranking questions for anatomical and technical risk factors respectively. Case 1 was designed to favour TEVAR in a hypertensive patient with partial false lumen thrombosis and large diameter (aortic≥40mm, false lumen≥22mm). Case 2 had no risk factors mandating TEVAR, according to current evidence. Cases 3, 4, and 5 were designed to test one risk factor respectively, large entry tear on the inner aortic curvature (≥10mm), partial false lumen thrombosis, and large diameter alone. There were 75 responses, 42 from EUR and 33 from ANZ. Almost half of surgeons (49.3%) endorsed pre-emptive TEVAR with 82.3% preferring to perform TEVAR in the subacute phase. In Case 1 and 5, 58.3% and 52.8% of surgeons respectively chose TEVAR, the highest rates obtained in the survey. Cases 1 and 5 included large diameters ≥40mm, which were ranked the highest in importance when surgeons considered anatomical risk factors. Surgeons who recommend pre-emptive TEVAR were more likely to choose TEVAR in both Case 1 (83.3% vs. 33.3%, p<.001, 95% CI 27.6%-65.8%) and Case 5 (69.4% vs. 38.2%, p=.008, 95% CI 8.2%-50.0%). In this survey about uncomplicated TBAD, about half of surgeons recommended pre-emptive TEVAR in selected cases. The surgeon's predisposition towards intervention and large diameters appear to be the most influential factors in decision making. These findings underline the uncertainty in today's practice and emphasise the need for better predictive tools.

Prevalence and the Relevance of CT-Morphologic Predictors for Disease Progression in Uncomplicated Type B Aortic Dissection

Introduction - To analyze the prevalence and significance of CT-morphologic predictors of aortic diameter expansion (ADE) in patients with uncomplicated acute Type B aortic dissection (TBAD). Methods - This retrospective analysis enrolled 65 patients (40 males, 25 females, mean age 58.3 ± 10.5 years) with TBAD under best medical treatment (BMT) between March 2003 and April 2016 at two tertiary centers. The initial (baseline) CT-scans and the one-year follow-up (median FU 11.6 months, IQR 8.4) scans were reviewed by two independent readers using a standardized measurement protocol and the centerline on a CE marked workstation. The following previously published independent predictors were analyzed: primary entry tear (PET) diameter ≥10 mm1, its location at the concavity of the aortic arch2, maximum descending aortic diameter ≥40 mm3, false lumen (FL) diameter ≥22 mm4, partial false lumen thrombosis5 and a fusiform index (FI) of ≥0.646. The endpoints were aortic expansion rate in mm at 1 year, prevalence of each and presence of multiple predictors. Results - An aortic diameter expansion (ADE) ≥5mm was observed in 37 out of 65 patients (57%) at 1 year. The extrapolated growth rate per 12 months averaged 8.2 ± 8.2 mm and the observed ADE was 6.2 ± 5.7 mm within the median FU. The regression analysis showed 2.5 ± 1.9 mm growth per predictor (CI -0.2-5.2 mm ± 0.7-3.0 mm; p=.003). ADE was accelerated by 1.9 mm per predictor within 1 year. The prevalence of predictors was: PET at the arch concavity in 11% (n=7), PET diameter ≥10 mm in 55% (n=36), maximal descending aortic diameter ≥40 mm in 38% (n=25), false lumen diameter ≥22 mm in 29% (n=19), partial false lumen thrombosis in 48% (n=31) and FI ≥ 0.64 in 18% (n=12). No predictors were found in 11% (n=7) of patients, one in 22% (n=14), two in 35% (n=23), three in 23% (n=15), four in 9% (n=6). A mean of 1.98 ± 1.1 predictors per patient were registered, 67% of patients presented at least 2 predictors each. Conclusion - A significant ADE is observed in every second uncomplicated TBAD patient under BMT within the first year following diagnosis. A correlation between the number of predictors and the annual growth rate was found. Therefore, CT-based predictors may help to define TBAD-patients at risk for expansion, and who may benefit from early endovascular repair. Further studies with larger cohorts and a longer FU are warranted.

Aortic growth and development of partial false lumen thrombosis are associated with late adverse events in type B aortic dissection

BackgroundPatients with medically treated type B aortic dissection (TBAD) remain at significant risk for late adverse events (LAEs). We hypothesize that not only initial morphological features, but also their change over time at follow-up are associated with LAEs. Materials and MethodsBaseline and 188 follow-up computed tomography (CT) scans with a median follow-up time of 4 years (range, 10 days to 12.7 years) of 47 patients with acute uncomplicated TBAD were retrospectively reviewed. Morphological features (n = 8) were quantified at baseline and each follow-up. Medical records were reviewed for LAEs, which were defined according to current guidelines. To assess the effects of changes of morphological features over time, the linear mixed effects models were combined with Cox proportional hazards regression for the time-to-event outcome using a joint modeling approach. ResultsLAEs occurred in 21 of 47 patients at a median of 6.6 years (95% confidence interval [CI], 5.1-11.2 years). Among the 8 investigated morphological features, the following 3 features showed strong association with LAEs: increase in partial false lumen thrombosis area (hazard ratio [HR], 1.39; 95% CI, 1.18-1.66 per cm2 increase; P < .001), increase of major aortic diameter (HR, 1.24; 95% CI, 1.13-1.37 per mm increase; P < .001), and increase in the circumferential extent of false lumen (HR, 1.05; 95% CI, 1.01-1.10 per degree increase; P < .001). ConclusionsIn medically treated TBAD, increases in aortic diameter, new or increased partial false lumen thrombosis area, and increases of circumferential extent of the false lumen are strongly associated with LAEs.

The distance of the primary intimal tear from the left subclavian artery predicts aortic growth in uncomplicated type B aortic dissection

ObjectiveControversy exists about the optimal treatment of acute uncomplicated type B aortic dissection (auTBAD). Optimal medical therapy (OMT) provides excellent short-term outcomes, but long-term results are poor. Ideally, auTBAD patients who will fail to respond to OMT in the chronic phase could be identified and undergo thoracic endovascular aortic repair. The purpose of this study was to identify radiographic predictors of auTBAD patients who will fail to respond to OMT. MethodsA review of the Emory aortic database from 2000 to 2017 identified 320 auTBAD patients initially treated with OMT. From this cohort, 121 patients with two or more contrast-enhanced imaging scans were available for analysis. These patients were initially divided into groups based on growth of the thoracic aorta ≥10 mm or intervention due to aneurysmal growth: growth (n = 72) and no growth (n = 49). TeraRecon (Foster City, Calif) imaging software was used to analyze characteristics of the primary intimal tear (PIT), false lumen, and overall aortic size. Finally, Cox proportional hazards models were constructed to estimate hazard ratios and to identify predictors of OMT failure. ResultsThe mean age of all patients was 54 ± 11 years, and 67% were male. Thirty-eight patients (53%) in the growth group underwent intervention. There were no differences between groups in age, hypertension, diabetes mellitus, tobacco abuse, or chronic obstructive pulmonary disease. The distance of the PIT from the left subclavian artery in patients with auTBAD was significantly shorter in the growth group (growth, 27 mm [9-66 mm]; no growth, 77 mm [26-142 mm]; P < .01). Multivariable Cox regression analysis identified the distance of the PIT from the left subclavian artery and a thoracic aortic diameter >45 mm as independent predictors of failure of OMT. Partial false lumen thrombosis was not a predictor of aortic growth. ConclusionsThe distance of the PIT from the left subclavian artery is a predictor of aortic growth in auTBAD. Patients with a primary tear located in zone 3 of the proximal descending thoracic aorta should be monitored closely and may be considered for early thoracic endovascular aortic repair in the setting of auTBAD.

Prevalence of the Computed Tomographic Morphological DISSECT Predictors in Uncomplicated Stanford Type B Aortic Dissection

The aim was to analyse the prevalence of computed tomographic (CT) morphological predictors and their influence on early chronic phase aortic diameter expansion in patients with uncomplicated acute Stanford type B aortic dissection (ATBAD). This retrospective analysis reviewed the CT imaging of 140 patients admitted with uncomplicated ATBAD to two tertiary centres between March 2003 and April 2016. The prevalence of the following CT-morphological predictors was determined at baseline: primary entry tear (PET) diameter≥10mm, its location at the concavity of the aortic arch; maximum descending aortic diameter≥40mm; false lumen (FL) diameter≥22mm; partial FL thrombosis and a fusiform index (FI) of ≥0.64. Thoracic aortic diameter expansion (ADE) was evaluated in 65 patients treated by best medical therapy (BMT) (median CT follow up 11.6 months). Study end points were predictor prevalence and ADE. A mean±SD of 2.45±1.35 predictors were registered among all 140 patients; 75.0% of patients showed at least two predictors. In 7.9% of patients, no predictor was found. The prevalence of PET at the arch concavity was 18.6%, PET diameter ≥10mm in 60.0%, maximal descending aortic diameter ≥40mm in 51.4%, FL diameter ≥22mm in 47.9%, partial FL thrombosis in 47.9%, and FI≥0.64 in 20.7%. An ADE ≥5mm was observed in 38 of 65 patients. Median observed ADE was 5.1mm (median follow up (FU) 11.6 months, range-3.2-27.4mm). Regression analysis for multiple predictors showed a basic ADE of 2.5mm plus 1.9mm per predictor at the median FU of 11.6 months (2.5mm±1.9; 95% confidence interval CI -0.2-5.2mm±0.7-3.0mm; p=.003). In the majority of patients, at least one of the investigated morphological predictors of disease progression in uncomplicated ATBAD was detected. An ADE ≥5mm affected 38 of 65 BMT patients. CT based predictors help to define TBAD patients at risk of progression.

Thoracic endovascular aortic repair to treat uncomplicated Stanford type B aortic dissection: The surgeon's dilemma to preventing future complications.

Uncomplicated type B aortic dissections have traditionally been managed non-operatively with aggressive blood pressure control. However, the best medical treatment is associated with a considerable risk of disease progression to complicated dissection or aneurysmal degeneration of the affected aortic segment. Thoracic endovascular aortic repair could prevent long-term complications but, because the dissected aorta is vulnerable, it is a high-risk procedure performed in asymptomatic patient. Therefore, endovascular treatment is not a solution for all patients and it should be performed only in the subgroup prone to developing progression of the disease and future complications. A number of studies have suggested several prognostic factors of early or late adverse events such as the patency of the false lumen in the follow-up, an initial aortic diameter ≥4 cm with a patent false lumen, an initial false lumen diameter ≥22 mm in the proximal descending aorta, visceral involvement and recurrent or refractory pain or hypertension. Partial false lumen thrombosis and a proximal entry tear size >10 mm have also been suggested to be associated with an increased rate of aortic growth. We need randomised trials focused on these prognostic factors to reach level 1, class A recommendation for the optimal timing of intervention. Meanwhile, we have to discuss with the patient the pro and cons of this prophylactic, low-invasive but high-risk treatment to personalise medical care and provide the optimal risk-to-benefit ratio.

Relationship between serum cortisol level and degree of false lumen thrombosis in patients with uncomplicated type B aortic dissection

Partial thrombosis of the false lumen in uncomplicated type B aortic dissection (uTBAD) is associated with an increased late mortality risk. Whether the serum cortisol level can affect false lumen thrombosis in patients with uTBAD has not been well characterized. This study was performed on 87 patients with uTBAD. A curve-fitting method was used to analyze the relationship between serum cortisol and partial thrombosis of false lumen. Univariate and multivariate logistic regression analyses were used to identify false lumen partial thrombosis–associated serum cortisol. Curve-fitting’s result revealed a characteristic U shape, and 14.0 µg/dL was considered as the cutoff point for serum cortisol. The results of univariate and multivariate logistic regression analyses suggested that when trisecting the serum cortisol level into three parts, the low and high levels of serum cortisol could significantly affect the occurrence of false lumen partial thrombosis compared with the middle level. The odds ratio value of the low and high levels of serum cortisol was 6.12 and 4.65, respectively, in the univariate analysis, and 24.32 and 3.93, respectively, in the multivariate analysis. Low or high levels of serum cortisol might influence the natural result of uTBAD through affecting the false lumen thrombosis.

Aortic Remodeling Following Sun's Procedure for Acute Type A Aortic Dissection.

BackgroundSun’s procedure is a surgical technique widely used in type A aortic dissection. The purpose of this study was to analyze clinical outcomes and morphologic changes in true and false lumen by computed tomography (CT) angiography after Sun’s procedure.Material/MethodsWe retrospectively reviewed 51 patients who underwent Sun’s procedure for acute Stanford type A aortic dissection extending down to iliac bifurcation between January 2013 and December 2014. The images of preoperative, one-month, three-month, and six-month follow-up were analyzed by CT angiography to measure the area and diameter of true and false lumen.ResultsFour patients died before surgical intervention and postoperative deaths occurred in five patients (in-hospital mortality rate 10.6%). Only 42 patients (36 male, 6 female; mean age, 45.9±9.8 years; range, 24–65 years) with acute type A aortic dissection were involved in our study. Thirty-five patients (83.3%) suffered from chest or abdominal pain and only one patient (2.4%) was asymptomatic. Thirty-seven patients (88.1%) had hypertension as the most common comorbidity. In the ascending aorta, false lumen was eliminated and the change of true lumen was not significant (p>0.05). In the descending aorta, complete and partial thrombosis of false lumen were observed in eight patients (19.0%) and 33 patients (78.6%) by one-month follow-up CT scan, respectively. After the six-month follow-up, the rate of complete thrombosis increased to 36.1% and partial thrombosis decreased to 61.9%. The area and maximal diameter of true lumen were increased significantly (p<0.05), whereas significant decreases were found in the area and maximal diameter of false lumen (p<0.05). In the abdominal aorta, thrombosis was found in 52.4% patients at one-month follow-up CT. Furthermore, there were no significant changes in both true and false lumen within three months (p>0.05). Nevertheless, the false luminal area and maximal diameter decreased significantly (p<0.05) after six months, while these changes of true lumen were not significant (p>0.05).ConclusionsAfter Sun’s procedure, aortic remodeling was a continuous process and occurred in a predictable model, and the extent of aortic remodeling varied at different levels. Remodeling in descending thoracic aorta was earlier than it was in abdominal aorta.

The Prevalence of Sleep Apnea in Type B Aortic Dissection: Implications for False Lumen Thrombosis.

Obstructive sleep apnea (OSA) has been implicated in aortic dissection. Thrombosis of the false lumen is associated with a prognosis of type B aortic dissection (AoD), and partial thrombosis has been reported to be an independent predictor of mortality. This study sought to explore whether the severity of OSA is associated with false lumen thrombosis. In this observational study, 151 type B AoD patients were recruited consecutively from 2013 to 2015. The status of the false lumen was classified as patent, partially thrombosed, or completely thrombosed based on a computer tomography angiography image. Patients were divided into non-OSA group (apnea-hypopnea index [AHI] < 5), and mild (5 ≤ AHI ≤ 15), moderate (15 < AHI ≤ 30), and severe OSA groups (AHI > 30) using the AHI. The prevalence of OSA in type B dissection was 66.2%. Among 151 cases, 51 patients (33.8%) were in the non-OSA group, 56 (37.1%) were in the mild group, 21 (13.9%) were in the moderate group, and 23 (15.2%) were in the severe group. Additionally, a partially thrombosed false lumen was observed in 88 patients (58.3%). Multivariable analysis revealed that OSA severity was positively associated with partial thrombosis (odds ratio, 1.784, 95% confidence interval: 1.182-2.691, P = .006) after adjusting for other confounding factors. OSA was present in two-thirds of patients with type B AoD. The severity of OSA was significantly associated with an increased risk of partial false lumen thrombosis. OSA may therefore be implicated in both the etiology and prognosis of AoD.

Replacement of ascending aorta and aortic arch combined with implantation of bare stent Djumbodis® Dissection System as a treatment of type I aortic dissection

Aim. The aim of this study is to show the outcomes of an open intervention on the ascending aorta and arch combined with stenting of aorta in type I aortic dissection.Methods. 6 patients with type I aortic dissection underwent implantation of Djumbodis® Dissection System bare stents at I.M. Sechenov First Moscow Medical University’s Aortic and Cardiovascular Surgery Clinic. In 4 patients, aortic stenting was combined with ascending aorta replacement, in 1 patient, hemiarch ascending aorta and arch replacement was performed and in 1 patient aorta and arch replacement was complemented with a Sun procedure.Results. Total operation time, cardiopulmonary bypass time, cross clamp time and hypothermic circulatory arrest time were just similar to those performed in conventional open surgery. There were no intraoperative deaths in this series. 30-day mortality was 16.7 % (1 patient). The patient died because of progressive respiratory and cardiovascular failure, encephalopathy, and gastrointestinal bleeding. 1 patient had acute renal failure and left leg ischemia because of the false lumen thrombosis, 1 patient suffered from cardiac tamponade and 1 patient underwent prolonged mechanical ventilation. Total false lumen thrombosis developed in 1 patient, 4 patients had partial false lumen thrombosis, and in 1 patient the false lumen remained patent.Conclusion. Stenting of aortic arch and descending aorta is a good alternative to aortic arch replacement in type I aortic dissection. It promotes stabilization of false and true lumen diameters and global aortic diameter.Received 18 October 2016. Accepted 7 November 2016.Funding: The study had no sponsorship.Conflict of interest: The authors declare no conflict of interest.Author contributionsConceptualization and study design: Komarov R.N., Soborov M.A.Material acquisition and analysis: Karavaykin P.A. Project curation: Komarov R.N., Belov Yu.V.Article writing: Karavaykin P.A. Review &amp; editing: Komarov R.N., Belov Yu.V., Soborov M.A.