Endovascular repair for retrograde type A intramural hematoma with focal intimal disruption in descending aorta

BackgroundThis study aims to report the experience of a single center using thoracic endovascular aortic repair (TEVAR) to treat retrograde type A intramural hematoma (IMH) with focal intimal disruption (FID) in descending aorta.MethodsA total of 24 consecutive patients with retrograde type A IMH and complicated with FID in descending aorta underwent TEVAR in our center from 2015 to 2020. Their clinical data, imaging manifestation and follow-up results were retrospectively reviewed and analyzed.ResultsThe median age of patients was 57.9 years (range, 42–80 years) and 18 were men (75%). As the preoperative CT angiography showed, the 24 patients developed IMH complicated with different kinds of FIDs in descending aorta [5 had intramural blood pool (IBP), 15 had ulcer-like projection (ULP), 2 had penetrating atherosclerotic ulcer (PAU), and 5 had localized dissection]. Successful deployment of aortic stent graft was achieved in all patients. There was no endoleak, stent graft migration, spinal cord ischemia, stroke, or 30-day mortality observed after TEVAR. The median duration of follow-up was 30.0 months (range, 3–60 months). As the last follow-up CT angiography showed, most of the patients (23 in 24, 96%) had favorable aortic remodeling. The maximum hematoma thicknesses and maximum diameters of both ascending and descending aorta were significantly decreased. During follow-up, 1 patient developed retrograde type A aortic dissection (RAAD) and underwent open surgery 3 months after TEVAR. 1 patient died of lung cancer 2 years later. There was no aorta-related death observed.ConclusionsTEVAR provides a safe and effective treatment strategy for selected patients with retrograde type A IMH, and FID developed in descending aorta could be the possible treatment target. However, RAAD remains one of the most serious postoperative complications of concern.     

Surgical timing of endoluminal repair of Stanford type B aortic coarctation and relationship to prognosis: a single-center retrospective cohort study

BackgroundStanford type B aortic dissection (TBAD) is a rare cardiovascular emergency with rapid onset and great harm. Currently, no relevant studies have analyzed the difference in clinical benefits of endovascular repair in patients with TBAD in acute and non-acute stages. To investigate the clinical characteristics and prognosis of endovascular repair in patients with TBAD at different surgical timing.MethodsThe medical records of 110 patients with TBAD from June 2014 to June 2022 were retrospectively selected as the study subjects. The patients were divided into an acute group (onset time ≤14 days) and a non-acute group (onset time >14 days) according to the time to surgery, and the two groups were compared in terms of surgery and hospitalization, aortic remodeling, and follow-up results. Univariate and multivariate logistic regression were used to analyze the factors affecting the prognosis of TBAD treated with endoluminal repair.ResultsThe proportion of pleural effusion, heart rate, the rate of complete thrombosis of the false lumen and the difference in the maximum diameter of the false lumen in the acute group were higher than those in the non-acute group (P=0.015, <0.001, 0.029, <0.001). The length of hospital stay and the maximum postoperative diameter of the false lumen was lower than in the non-acute group (P=0.001, 0.004). There was no statistically significant difference between the two groups in the technical success rate, overlapping stent length, overlapping stent diameter, immediate postoperative contrast type I endoleak, incidence of renal failure, ischemic disease, endoleaks, aortic dilatation, retrograde type A aortic coarctation, and death (P=0.386, 0.551, 0.093, 0.176, 0.223, 0.739, 0.085, 0.098, 0.395, 0.386); coronary artery disease [odds ratio (OR) =6.630, P=0.012], pleural effusion (OR =5.026, P=0.009), non-acute surgery (OR =2.899, P=0.037), and involvement of the abdominal aorta (OR =11.362, P=0.001) were all independent risk factors affecting the prognosis of TBAD treated with endoluminal repair.ConclusionsAcute phase endoluminal repair of TBAD may contribute to aortic remodeling, and the prognosis of TBAD patients can be assessed clinically in combination with coronary artery disease, pleural effusion, and involvement of the abdominal aorta for early intervention to reduce the associated mortality.     

Bentall procedure for retrograde type A dissection after endovascular repair in type A aortic dissection: A case report

Rationale:The management of retrograde type A dissection (RTAD) after thoracic endovascular aortic repair (TEVAR) for type A aortic dissection (TAAD) has rarely been reported. We report the management of RTAD after TEVAR with in situ fenestration for TAAD.Patient concerns:A 59-year-old man with TAAD had undergone TEVAR with in situ fenestration 4 months prior to presenting to our emergency room complaining of acute chest and back pain. Computed tomography angiography showed RTAD starting from the proximal endograft and extending to the aortic root.Diagnosis:The patient was diagnosed with RTAD.Interventions:We performed only the Bentall procedure, and the patient did not require total arch replacement. We removed the bare spring of the proximal endograft and anastomosed the prosthetic graft with the endograft and the native ascending aortic wall.Outcomes:The postoperative course was uneventful, and the patient remained asymptomatic for 3 years after surgery. Computed tomography angiography at the 3-year follow-up showed no perivalvular or anastomotic leakage.Lessons:RTAD after TEVAR for TAAD was safely and effectively treated by anastomosing the prosthetic graft with the endograft and the native ascending aortic wall instead of total arch replacement.     

Mobility of the Intimal Flap and Thrombus Formation in Aortic Dissection: A Transesophageal Echocardiographic Study

The mechanisms of the motion of the intimal flap and of thrombus formation in acute or chronic aortic dissection are not definitively elucidated. Transesophageal echocardiography seems to be a technique of choice to analyze the flow in the true and false lumina. Twenty-one consecutive patients were studied in order to define the mobility of the intimal flap, the color Doppler flow patterns, the presence of spontaneous echocardiographic contrast, and thrombus formation at different levels of the aorta. The results suggest that clotted false lumen is more often seen in chronic aortic dissection at the level of the descending thoracic aorta. However, thrombosed false lumen in the aortic arch is suggestive of a retrograde aortic dissection. In cases of complete obliteration of the false lumen, the differentiation between aortic dissection and aortic ectasia with mural thrombus may be extremely difficult.     

Short term outcome of thoracic endovascular aortic repair in patients with thoracic aortic diseases

Aim and background

Open surgical repair for thoracic aortic diseases is associated with a high perioperative mortality and morbidity. Most of type B aortic dissections are uncomplicated and are medically treated which carries a high mortality rate. Thoracic endovascular aortic repair is the first-line therapy for isolated aneurysms of the descending aorta and complicated type B aortic dissection. The aim of this study is to test the safety of early thoracic endovascular aortic repair in patients with uncomplicated type B aortic dissection and patients with thoracic aortic aneurysms.

National trends in repair for type B aortic dissection

BackgroundThoracic endovascular aortic repair (TEVAR) first gained in popularity for repair of type B aortic dissections (TBADs) in the early 2000''s. We aimed to describe patients undergoing open repair, TEVAR, and no repair and analyze factors associated with repair within 14 days of presentation in the contemporary era.MethodsWe used the MarketScan database to find patients with TBAD between 2014 and 2017. To assess factors associated with early repair, univariable, and multivariable log‐binomial regression were used.ResultsThere were 2613 patients admitted with TBAD between 2014 and 2017 across the United States, of whom 38.4% underwent repair within 14 days of admission (25.3% open repair and 13.1% TEVAR). The incidence of repair within 14 days decreased over the study period (43% of the study cohort in 2014 to 26.4% in 2017) primarily due to a decrease in open repairs from 30.8% of patients in 2014 to 12.5% in 2017. In multivariable analysis, older age, Middle Atlantic location, diabetes mellitus, insulin use, antiplatelet use, and more recent year were associated with lower likelihood of early repair; male sex, peripheral vascular disease, and the presence of extremity ischemia, rupture, shock, and acidosis were associated with higher likelihood of repair.ConclusionsOverall, repair of TBAD within 14 days of presentation declined from 2014 to 2017, with a steady rate of TEVAR but declining rate of open repairs. Further investigation into provider‐ and hospital‐specific factors as they relate to likelihood of repair is needed.     

Endovascular treatment of thoracic aortic disease: mid-term follow-up.

OBJECTIVE: The aim of this study was to evaluate the mid-term follow-up in a cohort of patients with acute or chronic descending aortic disease treated by stent-graft repair. BACKGROUND: Since 1999, endovascular stent-graft placement has been reported as an alternative treatment to surgical approach for a variety of thoracic aortic diseases; however, results beyond initial short-term follow-up are not widely available for the broad range of applications. METHODS: From March 2001, 43 consecutive patients with traumatic aortic transection (group A = 16) and complicated type B aortic dissection or aneurysm (group B = 27) underwent stent-graft implantation. All patients underwent computed tomography (CT) scan as preoperative assessment and in 26 a transesophageal echo (TEE) exam was performed. RESULTS: Technically successful stent-graft deployment was achieved in all patients. No patient required surgical conversion and no cases of paraplegia occurred. The overall in-hospital mortality was 9.3%. A residual endoleak (type II) was detected in one group B patient who was managed conservatively. The mean follow-up was 29 +/- 8 months (range 10-48 months). No patient died during late follow-up after hospital discharge. At 12 months, one patient (2.5%) who had stent graft repair of an aortic dissection developed an asymptomatic type I endoleak. Three asymptomatic patients with chronic dissection had a persistent retrograde perfusion of the thoracic false lumen via a distal tear(s) in the dissection septum. CONCLUSION: Our results of stent-graft treatment of complicated and uncomplicated diseases of the descending aorta confirms that this alternative to open repair is a safe, less invasive, and relatively low risk approach. Medium-term follow-up results suggest that it is effective and durable therapy with low associated mortality and morbidity rates.     

急性Stanford B型主动脉夹层腔内修复治疗时机与预后的关系

目的：探讨急性Stanford B型主动脉夹层（AADB）腔内修复治疗时机与预后的关系。方法回顾性分析接受经皮主动脉腔内修复术（TEVAR）的156例AADB患者的临床资料,分为发病至TEVAR时间≤7 d组（G1组）、发病至TEVAR时间为7～14 d组（G2组）和发病至TEVAR时间＞14 d组（G3组）,比较三组术后3个月主动脉修复情况、院内死亡、平均住院时间及住院费用。结果术前三组患者最小真腔直径与最大假腔直径的比值分别为（0.47±0.33）、（0.42±0.18）及（0.47±0.27）（P＞0.05）,术后3个月最大真腔直径与最大假腔直径比值分别为（1.76±0.51）、（1.42±0.30）及（1.34±0.34）,组间两两比较G1组显著大于G2组和G3组（P＜0.05）,G2组与G3组比较差异无统计学意义（P＞0.05）;术后3个月12例达到主动脉完全修复（G1组8例和G2组4例）;院内死亡患者8例,其中5例因脏器缺血致死,2例因近段夹层形成在术中死亡,1例为不明原因猝死;G1组和G2组的平均住院时间显著少于G3组（P＜0.05）,与G3组相比,G1组及G2组的住院费用减少了20000元/人。结论 AADB早期进行TEVAR术有利于术后主动脉修复,可以减少住院时间及费用且安全性可以接受。     

Stenting of a left main coronary artery dissection and stent-graft implantation for acute type a aortic dissection.

PURPOSE: To report successful endovascular repair of Stanford type A acute aortic dissection associated with a proximally extended dissection of the left main coronary artery. CASE REPORT: A 71-year-old man presented with acute type A aortic dissection. One day after admission, dissection of the left main coronary artery accompanied by severe myocardial ischemia prompted Palmaz stent placement. Three days later, a customized stent-graft was placed across the entry site of the dissection in the descending aorta. The false lumen in the ascending aorta, transverse arch, and the descending thoracic aorta thrombosed, and the left coronary artery remained patent. At 14 months after the procedures, the patient is doing well and has had no cardiac event. CONCLUSIONS: This staged procedure may be one option for the management of acute type A aortic dissection complicated by coronary artery dissection.     

The potential value of intravascular ultrasound imaging in diagnosis of aortic intramural hematoma

Objective To evaluate the potential value of intravascular ultrasound (IVUS) imaging in the diagnosis of aortic intramural hematoma (AIH). Methods From September 2002 to May 2005, a consecutive series of 15 patients with suspected aortic dissection (AD) underwent both IVUS imaging and spiral computed tomography (CT). Six patients diagnosed as acute type B AIH by CT or IVUS composed the present study group. Results The study group consisted of five males and one female with mean age of 66 years old. All of them had chest or back pain. In one patient, CT omitted a localized AIH and an associated penetrating atherosclerotic ulcer (PAU), which were detected by IVUS. In another patient, CT mistaken a partly thrombosed false lumen as an AIH, whereas IVUS detected a subtle intimal tear and slow moving blood in the false lumen. In the four rest patients, both CT and IVUS made the diagnosis of AIH, however, IVUS detected three PAUs in three of them, only one of them was also detected by CT, and two of them escaped initial CT and were confirmed by follow up CT or magnetic resonance imaging. Conclusions IVUS imaging is a safe examination and has high accuracy in the diagnosis of AIH, particularly for diagnosing localized AIH, distinguishing AIH with thrombosed classic AD and detecting accompanied small PAUs.     

Expanding false lumen in the abdominal aorta 5 years after endovascular repair of a type B aortic dissection: successful exclusion of 3 distal re-entry sites.

PURPOSE: To report endovascular treatment of an expanding aneurysmal false lumen several years after successful stent-graft deployment in the descending thoracic aorta for type B aortic dissection. CASE REPORT: A 54-year-old woman who had a stent-graft placed at the entry site of a type B aortic dissection 5 years prior presented with abdominal discomfort and palpable abdominal mass. Successful remodeling of the thoracic aorta was demonstrated by computed tomography; however, a false lumen aneurysm in the abdominal aorta had expanded from 4.8 to 6.5 cm and caused symptoms. She was successfully treated with 3 additional stent-grafts at 3 re-entry sites. Six months after the procedure, the false lumen aneurysm was completely excluded. CONCLUSIONS: Endovascular repair of the re-entry sites can prevent further expansion of false lumen aneurysm, which occurs in some patients with type B dissection treated with stent-grafts.     

Rapid progression of discrete type A intramural hematoma: prevention of a "procedure-related" complication by intraoperative transesophageal echocardiography.

PURPOSE: To report a case illustrating the utility of transesophageal echocardiography (TEE) before planned stent-graft placement for chronic type B aortic dissection. CASE REPORT: A 64-year-old man with acute aortic syndrome and an 8-year-old interposition graft in the distal aortic arch for acute type B dissection was referred for dissection of the descending thoracic aorta down to the aortic bifurcation; the false lumen was dilated to 65 mm and was partially thrombosed. The ascending aorta showed discrete, eccentric, 4-mm wall thickening that was not considered clinically significant. Stent-graft closure of the entry tear in the proximal descending thoracic aorta was elected. However, as the endovascular procedure was about to commence, TEE showed striking eccentric thickening of the aortic wall of up to 18 mm. The endovascular procedure was stopped, as it was decided to urgently replace the ascending aorta. The next day, the patient underwent successful ascending aortic replacement and simultaneous antegrade stent-graft implantation over the descending thoracic aortic entry tear via the open aortic arch. The postoperative course was uncomplicated, and the patient was discharged 19 days after surgery. He remains well at 6 months after the procedure. CONCLUSIONS: Our case demonstrates that dissection of the ascending aorta may occur not only due to endograft-induced intimal injury, but may also occur due to underlying but undiagnosed or underestimated disease of the ascending aorta or arch. Besides procedural guidance, intraoperative TEE is a useful tool to detect such disease to avoid subsequent "procedure-related" complications.     

Changes in aortic arch geometry and the risk for Stanford B dissection

BackgroundThe increase in aortic diameter is not closely associated with type B aortic dissection (TBAD); morphological risk factors other than aortic diameter may help to better identify patients at risk for TBAD. The purpose of this study was to investigate possible morphological factors associated with the occurrence of TBAD.MethodsThis study was a retrospective, multicenter, cross-sectional study. We collected 94 patients with TBAD as the TBAD group and 534 patients with healthy aortas as the healthy control group. Morphometric data were collected on three-dimensional models of the thoracic aorta. A propensity score matching (PSM) analysis was conducted to reduce the potential for confounding by baseline factors.ResultsThe number of patients in the TBAD group was 75 after PSM. Longer lengths of the aortic arch (28.00±7.42 vs. 25.14±7.11 cm) were observed in patients with TBAD. The width (80.04±17.27 vs. 71.73±15.55 mm) and height (24.92±11.39 vs. 19.37±10.10 mm) of the aortic arch in patients with TBAD were both larger than those of healthy controls. The morphological changes associated with the occurrence of type B acute dissection were most pronounced in the geometry of the aortic arch.ConclusionsThis study demonstrates that TBAD was associated with longer lengths of aortic arch and with larger arch height and width.     

DeBakeyⅢ型主动脉夹层21例的临床诊治

目的 探讨主动脉腔内隔绝术（endovascular aortic repair,EVAR）治疗DeBakeyⅢ型主动脉夹层的技术方法及疗效.方法 对近3年江西省人民医收治的21例DeBakeyⅢ型主动脉夹层患者的临床资料进行回顾性分析.19例患者均行左锁骨下动脉穿刺,行升主动脉造影,了解主动脉真假腔、夹层裂口及其与重要血管分支的位置关系.切开右侧股动脉置入覆膜血管内支架,封堵原发破口,置入支架后重复造影检查以观察真假腔血流变化、主动脉分支供血的情况.结果 19例患者支架置入定位准确,术后即刻造影显示真腔血流恢复正常.手术成功率100％,无截瘫及瘤体破裂等严重并发症,无围术期死亡.所有患者术后3～6个月复查增强计算机断层扫描,假腔不再显影,支架通畅,无扭曲、移位.结论 EVAR治疗DeBakeyⅢ型主动脉夹层是安全有效的,但远期效果有待进一步观察.     

DeBakeyⅢ型主动脉夹层腔内隔绝术后近端Ⅰ型内漏的影响因素分析

目的 探讨DeBakeyⅢ型主动脉夹层患者行主动脉腔内隔绝术（thoracic endovascular aortic repair,TEVAR）后近端Ⅰ型内漏的影响因素.方法 对东莞康华医院2009年6月至2014年7月期间83例行TEVAR术的DeBakeyⅢ型主动脉夹层患者的临床资料进行回顾性分析.术中及术后分别采用主动脉数字减影血管造影（DSA）以及螺旋三维计算机断层扫描对内漏进行评估.术后随访时间为2-63个月.结果 83例患者中出现近端Ⅰ型内漏10例,术中出现内漏者6例,迟发性Ⅰ型内漏4例.结论 Ⅰ型内漏是TEVAR术的常见并发症,血管因素、移植物的选择以及术者的经验均可影响内漏的发生.     

Endovascular stent-grafts treatment in acute aortic dissection (type B): clinical outcomes during early, late, or chronic phases.

OBJECTIVE: This is a prospective study to evaluate the clinical outcomes of endovascular repair in patients with different phases of type B aortic dissection. BACKGROUND: Endovascular repairing with stent-grafts is an innovative technique for type B acute aortic dissection. There is no previous study regarding outcomes in different time phases. METHODS: Sixty-two patients underwent endovascular stent-grafts. There were 23 in the early phase (<24 hr), 20 in the late phase (>or=24 hr to 2 weeks), and 19 in the chronic phase (>2 weeks). RESULTS: The early phase group had the lowest ratio of stent-grafts to patient and the shortest stent-graft length. The chronic phase group had the largest diameter of false lumen. The technical success rate was 100%; no patient died within hospital. Three patients died within 30 days, with the same death rate in every group. Compared with acute patients, the chronic group had a higher volume of contrast, a higher creatinine post-procedure, and a higher incidence of contrast-induced nephropathy. Multiple regression analysis demonstrated that creatinine and endoleak were independent factors in predicting late death (95% CI, 3.4-26%, P < 0.01). The overall cardiovascular event-free survival was 88.9% +/- 2.1% at 30 days, 87.2% +/- 4.1% at 1 year, and 81.4% +/- 6.3% at 2 years. CT angiography identified the complete or partial thrombosis of the false lumen to be 95.7%. CONCLUSIONS: Endovascular repairing with stent-graft is safe, feasible, and able to treat type B aortic dissection in all phases. However, chronic renal dysfunction was an independent factor which contributed to a lower survival rate of chronic phase patients.     

Long-term prognosis of acute aortic dissection with medical treatment: a survey of 263 unoperated patients

Between 1973 and 1998, 263 patients with acute aortic dissection were medically treated only. They were divided into 4 groups: Stanford type A and B with open false lumen (open) or with early thrombosed false lumen (thrombosed). An event was defined as death by dissection or re-dissection. Gender, age, maximum diameter of dissected aorta and presence of shock at onset were examined as risk factors. In the open false lumen group, the presence of shock was associated with the event. During the chronic period, the diameter of the aorta was associated with prognosis in open type B dissection. The rate of event was higher in the open type A and B groups than in the thrombosed type A and B groups; however, there was no difference in the event-free rate between types A and B in patients surviving the acute period. The prognosis of medically treated dissecting aorta was not poor in patients with type B or with early thrombosed false lumen. The presence of shock at onset with open false lumen and the diameter of the aorta (> or =40 mm) in type B were significantly correlated with a poor prognosis.     

Risk factors for distal stent graft-induced new entry following endovascular repair of type B aortic dissection

Background

Distal stent graft-induced new entry (DSINE) has been increasingly observed following thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD). We seek to identify the risk factors for DSINE following TEVAR in patients with TBAD.

Methods

Between January 2009 and January 2013, we performed TEVAR for 579 patients with TBAD. The clinical data were retrospectively analyzed with univariate and multivariate analyses to identify the risk factors for DSINE.

Results

Two patients (0.3%) died after the initial TEVAR. Morbidity included spinal cord injury in 2 (0.3%), stroke in 3 (0.5%) and endoleak in 12 (2.1%) patients. Clinical and radiological follow-up was complete in 100% (577/577) averaging 47±16 months. Late death occurred in 6 patients. DSINE occurred in 39 patients (6.7%) at mean 22±17 months after the initial TEVAR, which was managed with re-TEVAR in 25 and medically in 14. At 33±18 months after DSINE, 11 of patients managed medically (11/14) and all patients managed with re-TEVAR (25/25) survived (P=0.048). Freedom from DSINE was 92.7% at 5 years (95% CI: 90.0-94.7%). Using tapered stent grafts with a proximal end 4-8 mm larger than the distal end, TEVAR performed in the acute phase (≤14 days from onset) was associated with a significantly lower incidence of DSINE than TEVAR performed in the chronic phase (4.3%, 7/185 vs. 13.9%, 15/108; P=0.003). Risk factors for DSINE were stent grafts less than 145 mm in length [odds ratio (OR) 2.268; 95% CI: 1.121-4.587; P=0.023] and TEVAR performed in the chronic phase (OR 1.935; 95% CI: 1.004-3.731; P=0.049).

Conclusions

Our results show that TEVAR performed during the acute phase and using stent grafts longer than 145 mm could decrease the incidence of DSINE in patients with TBAD. Tapered stent grafts with a proximal end 4-8 mm larger than the distal end may be helpful in preventing DSINE after TEVAR performed in the acute phase than TEVAR performed in the chronic phase, due to the difference in mobility of the dissected flap. Expedite repeat TEVAR is recommended to improve the clinical prognosis for patients with DSINE.     

Thrombotic thrombocytopenic purpura complicated with acute aortic dissection: A case report

Rationale:Thrombotic thrombocytopenic purpura (TTP) is a critical thrombotic microangiopathy involving multiple organs. To the best of our knowledge, there are no reports of TTP complicated by acute aortic dissection.Patient concerns:We herein described a 53-year-old male with TTP who did not have a significant medical history. After immediate plasma exchange and glucocorticoid therapy, the patient''s clinical condition improved. However, the patient suddenly experienced chest pain with elevated blood pressure.Diagnoses:Computed tomography angiography suggested acute type B aortic dissection.Interventions:The patient was immediately transferred to the cardiac aortic surgery department for thoracic aortic endovascular repair.Outcomes:The patient was discharged after successful thoracic aortic endovascular repair. Unfortunately, 3 months later, the patient experienced chest and back pain at home and died suddenly, possibly due to the recurrence of aortic dissection.Lessons:Even if patients have no identifiable risk factors, physicians should be aware of this rare and life-threatening acute complication of TTP, which may have multiple causes, including preexisting connective tissue disease, abnormal blood pressure fluctuations, and increased risk of hemorrhage. Early identification and timely treatment of acute aortic dissection are critical for improving prognosis.     

Computed tomography of aortic intramural hematoma and thrombosed dissection

A retrospective study was undertaken to evaluate the appearance of the aortic wall on computed tomography for the purpose of developing criteria for differentiating acute aortic intramural hematoma from thrombosed false lumen seen in aortic dissection. Computed tomography angiography findings of the thoracoabdominal aorta in 23 patients with suspected intramural hematoma and 25 with thrombosed false lumen were reviewed. The more common features of an intramural hematoma were hyperattenuation of the aortic wall, wall thickness less than a quarter of the aortic diameter, intrinsic wall calcification, a lesion extending around the entire aortic circumference, and ulcer-like projections that may be precursors of intramural hematoma. Wall thickness less than a quarter of the aortic diameter, lesion extending around the entire aortic circumference, and ulcer-like projections were the most useful indicators for distinguishing intramural hematoma from the thrombosed false lumen in aortic dissection.