New development of an ulcerlike projection in aortic intramural hematoma: CT evaluation

Natural history and long-term outcomes of medically managed Type B intramural hematoma

OBJECTIVE

Type B intramural hematoma (IMH) is often managed medically, yet may progress to dissection, aneurysmal dilation, or rupture. The aim of this study was to report the natural history of medically managed Type B IMH, and factors associated with progression.

METHODS

We reviewed patients with medically managed Type B IMH between January 1995 to December 2022 at a single center. Any patients with immediate surgical or endovascular intervention were excluded. Demographic profiles, comorbidities, imaging, and follow-up details were reviewed. Patients were divided into two groups: Group 1 had isolated IMH, and Group 2 had IMH along with aneurysm or dissection at the time of presentation. On follow-up, progression was defined as degeneration to aneurysm/dissection or increase in the thickness of IMH in Group 1. In Group 2, progression was an increase in the size of aneurysm or development of new dissection.

RESULTS

Of 104 patients with Type B IMH during the study period, 92 were medically managed. The median age was 77 years, and 45 (48.9%) were females. Comorbidities included hypertension (83.7%), hypercholesterolemia (44.6%), and active smoking (47.8%). Mean Society for Vascular Surger comorbidity score was 6.3. Mean IMH thickness and aortic diameter at presentation were 8.9 mm and 38.3 mm, respectively. Median follow-up was 55 months. Overall survival at 1 year and 5 years was 85.8% and 61.9%, respectively. During follow-up, 19 patients (20.7%) required intervention, more common in Group 2 (Group 1, 8/66; 12.3% vs Group 2, 11/26; 42.3%; P = .001). This resulted in higher freedom from intervention in Group 1 at 1 year (93.5% vs 62.7%) and 5 years (87.5% vs 51.1%; P < .001). Indication for intervention was dissection (n = 4), aneurysm (n = 12), and progression of IMH (n = 3). In Group 1, progression was seen in 25 (37.9%), three (4.5%) remained stable, 29 (43.9%) had complete resolution of IMH, and nine patients were lost to follow-up. In Group 2, 11 patients (42.3%) had progression, seven (26.9%) remained stable, and eight were lost to follow-up. IMH thickness at presentation >7.2 mm is associated with both increased odds of progression (odds ratio, 3.3; 95% confidence interval, 1.2-11.1; P = .03) and intervention (odds ratio, 5.5; 95% confidence interval, 1.3-36.9; P = .03) during the follow-up.

CONCLUSIONS

Although many patients with Type B IMH managed medically stabilize or regress, progression or need for intervention can occur in up to 40% of cases. This is associated with the presence of aneurysm, dissection, and IMH thickness. Long-term follow-up is mandatory as late interventions occur, particularly for higher risk patients.

Features and outcomes of focal intimal disruption in acute type B intramural haematoma

OBJECTIVES

A focal intimal disruption (FID) is a risk factor for adverse aorta-related events in patients with acute type B intramural haematoma. This study evaluated the impact of FIDs on overall survival with a selective intervention strategy for large or growing FIDs. Additionally, this study evaluated the risk factors associated with the growth of FIDs.

METHODS

This retrospective study included all consecutive patients admitted for acute type B intramural haematomas between November 2004 and April 2021. The primary outcome was overall survival. The secondary outcome was the cumulative incidence of composite aortic events and the growth of FIDs. The latter was calculated on centreline-reconstructed computed tomography images.

RESULTS

A total of 105 patients were included. A total of 106 FIDs were identified in 73 patients (73/105, 69.5%). The 1- and 5-year cumulative incidence rates of composite aortic events were 36.2% and 39.2%, respectively. The 1- and 5-year overall survival was 93.3% and 81.5%, respectively. Initial maximal aortic diameter and large FIDs during acute phase were significant risk factors for composite aortic events, but not risk factors for overall survival. The early appearance interval of an FID was a significant risk factor for growth of an FID.

CONCLUSIONS

With a selective intervention strategy for large or growing FIDs, the presence of large FIDs during the acute phase does not affect overall survival. The early appearance interval was associated with the growth of FIDs.

Prognostic Implications of Initial Focal Contrast Enhancement in Acute Type B Intramural Hematoma

BACKGROUND

The prognostic implication of initial focal contrast enhancement (FCE), including focal intimal disruption (FID) and intramural blood pool (IBP), in acute type B intramural hematoma (IMH) remain unclear.

OBJECTIVES

The purpose of this study was to compare the prognostic implications in IMH with or without FCE.

METHODS

A total of 574 patients were enrolled. FID was defined as an intimal disruption with contrast-filled out-pouching from the aorta lumen with a communicating orifice of >3 mm, and IBP was defined as a localized contrast medium-filled pool inside the IMH.

RESULTS

A total of 207 (36.1%) patients with initial FCE, including 132 (63.8%) FIDs and 75 (36.2%) IBPs, were identified. Patients with FCE accompanying IMH were more likely to have hypertension (P = 0.001), pleural effusion (P = 0.006), fewer aortic segments involved (P < 0.001), more adverse aortic events (AAEs) (P < 0.001), and fewer freedom from intervention (P = 0.002). Pleural effusion (HR: 1.79; 95% CI: 1.25-2.55; P = 0.001) and FCE (HR: 1.51; 95% CI: 1.12-2.02; P = 0.006) were identified to be the independent risk factors of AAEs. In the subgroup analysis, IMH with initial FID were more likely to progress than those with initial IBP (P < 0.001). FIDs located at the proximal descending aorta (HR: 2.95; 95% CI: 1.65-5.29; P < 0.001) were associated with AAEs.

CONCLUSIONS

Patients with FCE accompanying IMH were more likely to progress, especially in those initial FID localized at the proximal descending aorta. (Nature course and predictors of progression of intramural hematoma: A retrospective, multicenter study; ChiCTR2300073829).

A Comparison of Retrospective ECG-Gated CT and Surgical or Angiographical Findings in Acute Aortic Syndrome

The best cardiac phases in retrospective ECG-gated CT for detecting an intimal tear (IT) in aortic dissection (AD) and an ulcer-like projection (ULP) in an intramural hematoma (IMH) have not been established. This study aimed to compare the detection accuracy of diastolic-phase and systolic-phase ECG-gated CT for IT in AD and ULP in IMH, with subsequent surgical or angiographical confirmation as the reference standard.In total, 81 patients (67.6 ± 11.8 years; 41 men) who underwent emergency ECG-gated CT and subsequent open surgery or thoracic endovascular aortic repair for AD (n = 52) or IMH (n = 29) were included. The accuracies of detecting IT and ULP were compared among only diastolic-phase, only systolic-phase, and both diastolic-phase and systolic-phase methods of retrospective ECG-gated CT; surgical or angiographical findings were used as the reference standard. The detection accuracy for IT and ULP using only diastolic-phase, only systolic-phase, and both diastolic-phase and systolic-phase methods of ECG-gated CT was 93% [95% CI: 87-97], 94% [95% CI: 88-97], and 95% [95% CI: 90-97], respectively. There were no significant differences in detection accuracy among the 3 acquisition methods (P = 0.55). Similarly, there were no significant differences in the accuracy of detecting IT in AD (P = 0.55) and ULP in IMH (P > 0.99) among only diastolic-phase, only systolic-phase, and both diastolic- and systolic-phase ECG-gated CT.Retrospective ECG-gated CT for detecting IT in AD and ULP in IMH yields highly accurate findings. There were no significant differences seen among only diastolic-phase, only systolic-phase, and both diastolic-phase and systolic-phase ECG-gated CT.

Clinical and imaging differences between Stanford Type B intramural hematoma-like lesions and classic aortic dissection

BACKGROUND

Intramural hematoma (IMH) and Aortic dissection (AD) have overlapping features. The aim of this study was to explore the differences between them by comparing the clinical manifestations and imaging features of patients with acute Stanford type B IMH-like lesions and acute Stanford type B AD (ATBAD).

METHODS

This study retrospectively analysed the clinical and computed tomography angiography (CTA) imaging data of 42 IMH-like lesions patients with ulcer-like projection (ULP) and 38 ATBAD patients, and compared their clinical and imaging features.

RESULTS

(1) The IMH-like lesions patients were older than the ATBAD patients (64.2 ± 11.5 vs. 50.9 ± 12.2 years, P < 0.001). The D-dimer level in the IMH-like lesions group was significantly higher than that in the ATBAD group (11.2 ± 3.6 vs. 9.2 ± 4.5 mg/L, P < 0.05). The incidence rate of back pain was significantly higher in the ATBAD group than in the IMH-like lesions group (71.1% vs. 26.2%, P < 0.05). (2) The ULPs of IMH-like lesions and the intimal tears of ATBAD were concentrated in zone 4 of the descending thoracic aorta. The ULPs of IMH-like lesions and the intimal tears of ATBAD were mainly in the upper quadrant outside the lumen (64.3% vs. 65.8%, P > 0.05). (3) The maximum diameter of the ULPs in IMH-like lesions was smaller than that of the intimal tears in ATBAD (7.4 ± 3.4 vs. 10.8 ± 6.8 mm, P = 0.005). The lumen compression ratio in the ULPs plane and the maximum compression ratio of the aortic lumen in the IMH-like lesions group were smaller than that in the ADBAD group (P < 0.05). Fewer aortic segments were involved in IMH-like lesions patients than in ATBAD patients (5.6 ± 2.2 vs. 7.1 ± 1.9 segments, P < 0.005). The IMH-like lesions group had less branch involvement than that of the ATBAD group (P < 0.001).

CONCLUSION

The degree of intimal tears, lumen compression ratio, extent of lesion involvement, and impact on branch arteries in ATBAD are more severe than that of IMH-like lesions. But for the ULPs of IMH-like lesions and intimal tears of ATBAD, they have astonishing similarities in the location of the partition and the lumen quadrant, we have reason to believe that intimal tear is the initial factor in the pathogenesis of this kind of disease, and their clinical and imaging manifestations overlap, but the severity is different. Concerning similarities between these two conditions, these two may be a spectrum of one disease.

CT characteristics and clinical implications of acute type A aortic intramural hematoma

Objectives

Computed tomography (CT) has been increasingly used in the diagnosis of acute aortic syndrome, and a number of high-risk CT imaging features have been reported. We aimed to identify CT imaging findings suggesting high-risk for acute aortic syndrome by examining clinical outcomes of patients with acute type A aortic intramural hematoma (TAIMH).

Methods

This retrospective study analyzed the relationship of clinical patient characteristics and imaging features with mortality and aortic events in 63 patients receiving initial medical treatment for TAIMH. Multivariate regression analysis was used to determine the predictors of aortic events, and the Kaplan-Meier method was used to analyze survival and aortic events.

Results

During a median follow-up of 4.2 years, 25 patients experienced aortic events and 40% of these occurred within 7 days of admission. In total, 12 patients experienced aortic death and 12 patients underwent open aortic surgery or endovascular stenting for aortic disease. In multivariate regression analysis, penetrating atherosclerotic ulcers (PAUs) or ulcer-like projections (ULPs) (P = 0.04) and pericardial effusion (P = 0.03) were independent predictors of aortic events. In the Cox regression model, PAUs/ULPs (P = 0.04) and pericardial effusion (P = 0.04) were independently associated with lower aortic event-free survival.

Conclusion

Identification of high-risk CT features is important for clinical decision-making during TAIMH treatment. Early and frequent CT imaging follow-up is required in patients receiving medical treatment. PAUs/ULP and pericardial effusion were the strongest predictors of adverse aortic events.

Significance of systolic-phase imaging on full-phase ECG-gated CT angiography to detect intimal tears in aortic dissection

Purpose

For patients with aortic dissection (AD) and intramural hematoma (IMH), the optimal cardiac phase to detect intimal tears (IT) and ulcer-like projections (ULP) on retrospective electrocardiogram (ECG)-gated computed tomography angiography (CTA) remains unclear. The purpose of this study was to compare the accuracy of retrospective ECG-gated CTA for detecting IT in AD and ULP in IMH between each cardiac phase.

Materials and methods

A total of 75 consecutive patients with AD and IMH of the thoracic aorta were enrolled in this single-center retrospective study. The diagnostic performance to detect IT and ULP in the thoracic aortic regions (including the ascending aorta, aortic arch, and proximal and distal descending aorta) was compared in each cardiac phase on retrospective ECG-gated CTA.

Results

In the systolic phase (20%), the accuracy, sensitivity, and specificity to detect IT in AD was 64% (95% confidence interval [CI] 56–72%), 69% (95%CI 60–78%), and 25% (95%CI 3.3–45%), respectively. In the diastolic phase (70%), the accuracy, sensitivity, and specificity to detect IT in AD was 52% (95%CI 43–60%), 52% (95%CI 42–61%), and 50% (95%CI 25–75%), respectively. The accuracy to detect IT in AD on ECG-gated CTA was significantly higher in the systolic phase than that in the diastolic phase (P = 0.025). However, there were no differences in the accuracy (83%; 95%CI 78–89%), sensitivity (71%; 95%CI 62–80%), or specificity (100%; 95%CI 100%) to detect ULP in IMH between the cardiac cycle phases.

Conclusion

Although it is currently recommended for routine diagnosis of AD and IMH, single-diastolic-phase ECG-gated CTA has risk to miss some IT in AD that are detectable in the systolic phase on full-phase ECG-gated CTA. This information is critical for determining the optimal treatment strategy for AD.

MDCT Imaging of Non-Traumatic Thoracic Aortic Emergencies and Its Impact on Diagnosis and Management—A Reappraisal

Non-traumatic thoracic aorta emergencies are associated with significant morbidity and mortality. Diseases of the intimomedial layers (aortic dissection and variants) have been grouped under the common term of acute aortic syndrome because they are life-threatening conditions clinically indistinguishable on presentation. Patients with aortic dissection may present with a wide variety of symptoms secondary to the pattern of dissection and end organ malperfusion. Other conditions may be seen in patients with acute symptoms, including ruptured and unstable thoracic aortic aneurysm, iatrogenic or infective pseudoaneurysms, aortic fistula, acute aortic thrombus/occlusive disease, and vasculitis. Imaging plays a pivotal role in the patient’s management and care. In the emergency room, chest X-ray is the initial imaging test offering a screening evaluation for alternative common differential diagnoses and a preliminary assessment of the mediastinal dimensions. State-of-the-art multidetector computed tomography angiography (CTA) provides a widely available, rapid, replicable, noninvasive diagnostic imaging with sensitivity approaching 100%. It is an impressive tool in decision-making process with a deep impact on treatment including endovascular or open surgical or conservative treatment. Radiologists must be familiar with the spectrum of these entities to help triage patients appropriately and efficiently. Understanding the imaging findings and proper measurement techniques allow the radiologist to suggest the most appropriate next management step.

Thoracic Endovascular Aortic Repair for Retrograde Type A Aortic Intramural Hematoma

Objectives: To evaluate the effects of thoracic endovascular aortic repair (TEVAR) in descending aorta for retrograde type A aortic intramural hematoma (re-TAIMH).

Methods: From January 2013 to September 2019, 65 consecutive patients diagnosed with re-TAIMH and treated by TEVAR were enrolled in this retrospective cohort study, of whom 44 patients presented with entry tear in descending aorta (Group A) and 21 with penetrating atherosclerotic ulcer (Group B). The clinical data, including baseline characteristics, adverse events, aortic remolding, and overall survival were reviewed.

Results: The mean age of all the patients was 52.0 ± 8.3 years, and 54 (83.1%) patients were men. The mean maximal ascending aortic diameter (MAAD) was 43.1 ± 5.4 mm, and the mean maximal ascending aortic hematoma thickness (MAAHT) was 9.6 ± 4.7 mm. TEVAR was performed under general anesthesia in 53 (81.5%) patients, while 12 (18.5%) patients were treated under local anesthesia. There were two deaths during hospitalization (one with rupture and another with multiple organ dysfunction syndrome), and overall survival at 1, 4, and 7 years for all 65 patients was 93.8, 92.0, and 87.4%, respectively. The MAAD and MAATH decreased significantly after TEVAR (p < 0.05) in the two groups, so did the mean descending aortic diameter at the pulmonary bifurcation level. Type I endoleak, dialysis, progression to type A aortic dissection, and enlargement in MAAHT and MAAD were more common complications, which occurred in four, three, two, and two patients, respectively.

Conclusion: Patients with retrograde TAIMH treated by TEVAR had a favorable prognosis including late survival and aortic remolding. However, some post-intervention complications were not negligible.

Focal Intimal Disruption Size at Multidetector CT and Disease Progression in Type B Aortic Intramural Hematoma

Background Recent imaging techniques show that patients with aortic intramural hematoma (IMH) have various sizes of focal intimal disruptions (FIDs) that may affect clinical outcomes. Purpose To evaluate the relationship between size of FIDs detected at multidetector CT and disease progression in patients with type B IMH. Materials and Methods This retrospective study analyzed consecutive patients with type B IMH who underwent multidetector CT at admission within 24 hours after symptom onset from January 2011 to March 2017. FID was defined as a focal contrast material-filled pouch projecting outside of the aorta lumen with a communicating orifice greater than 3 mm. Large FID was defined as an FID of at least 10 mm in length and width and at least 5 mm in depth. Aorta-related events were defined as a composite of aortic rupture, surgical or endovascular aortic repair, progressive aortic enlargement, and development of aortic dissection. Results Seventy-six patients (mean age, 72 years ± 11 [standard deviation]; 54 men) were evaluated. Fifty patients (66%; 50 of 76) had 91 FIDs. Twenty-eight patients had large FIDs and 22 patients had small FIDs. Aorta-related events occurred in 15 of 28 patients with large FIDs, two of 22 patients with small FIDs, and four of 26 patients with no FID. Patients with large FIDs showed lower aorta-related event-free survival rates than did patients with small FIDs or no FID (small FIDS, 63% ± 10 vs 90% ± 7 at 3 years, respectively [P = .001]; and no FIDS, 63% ± 10 vs 84% ± 7 at 3 years, respectively [P = .005]). Multivariable analysis showed that a maximum aortic diameter of at least 40 mm (hazard ratio, 4.8; 95% CI: 1.8, 12.6; P = .001) and large FID (hazard ratio, 3.2; 95% CI: 1.1, 8.9; P = .03) were the independent predictors of aorta-related events. Conclusion A large portion of patients with B-intramural hematoma (IMH) had focal intimal disruption (FID) detected at CT at admission. Large FIDs were associated with disease progression of IMH. © RSNA, 2021 See also the editorial by Raptis and Braverman in this issue. Online supplemental material is available for this article.

Risk stratification of ulcer-like projection in uncomplicated acute type B aortic intramural haematoma

OBJECTIVES

This study aimed to investigate the morphological evolution and risk stratification of ulcer-like projection (ULP) in patients with uncomplicated acute type B aortic intramural haematoma.

METHODS

A retrospective study was conducted on patients with uncomplicated acute type B intramural haematoma admitted in our institution from January 2015 to June 2020. The primary end points were adverse aortic events (AAE), including aortic rupture, aortic dissection, aortic aneurysm and ULP enlargement.

RESULTS

The study cohort comprised 140 patients, including 62 (44%) and 78 (56%) patients with and without initial ULP, respectively. AAE occurred in 13 patients (9%) in the early term and 42 patients (33%) in the mid-term. Compared with patients without ULP, patients with initial ULP had no significant difference in early outcomes but a higher mid-term AAE rate [8% vs 11%, odds ratio (OR) 1.5, P = 0.47; 17% vs 55%, OR 6.0, P < 0.001]. Significantly higher AAE rate was observed in patients with high-risk ULP (depth ≥5.0 mm and located in the proximal aortic segments) than those with only low-risk ULP (depth <5.0 mm and/or located in the distal aortic segments) (87% vs 51%, OR 6.2, P = 0.014). In the multivariable analysis, high-risk ULP was an independent predictor of AAE (hazard ratio 2.8, P = 0.009).

CONCLUSIONS

High-risk ULP is a rapidly evolving entity and a marker of AAE despite optimal medical therapy. Therefore, close follow-up and prompt intervention are recommended for patients with high-risk ULP.

Clinical features and outcomes after endovascular therapy for penetrating aortic ulcer and intramural hematoma

OBJECTIVES

To identify the differences between clinical features and outcomes after endovascular therapy for penetrating aortic ulcer (PAU) and intramural hematoma (IMH).

METHODS

From January 2009 to March 2020, patients who underwent endovascular therapy for PAU and IMH were enrolled. Information on patient demographics, presentation, PAU and IMH morphology, laboratory examination, and clinical follow-up information was collected and analyzed. Univariate analysis was performed to identify the differences between IMH and PAU, and Kaplan-Meier was used to calculate the cumulative survival rate and freedom from reintervention.

RESULTS

A total of 114 patients were enrolled; 80 (70.2%) of them were diagnosed with PAU. Compared with PAU, patients with IMH were younger (p = 0.006), more likely to be admitted emergently (p = 0.001), had longer hospital stay (p = 0.028), and had higher levels of C-reactive protein (p = 0.030). Meanwhile, patients with IMH were more likely to be associated with hypertension (p = 0.020) and pleural effusion (p < 0.001) and less likely to have a history of acute coronary syndrome (p = 0.019) and prior cardiovascular intervention (p = 0.017). The five-year freedom from reintervention and cumulative survival rate were 94.2% (95% confidential interval, 88.9%-99.9%) and 87.8% (95% confidential interval, 79.5%-96.9%) in PAU patients and 89.6% (95% confidential interval, 75.8%-99.9%) and 85.1% (95% confidential interval, 68.0%-99.9%) in IMH patients, respectively. There was no significant difference in freedom from reintervention (p = 0.795) or cumulative survival rate (p = 0.817).

CONCLUSIONS

IMH appeared to occur in younger patients with hypertension and usually had an acute onset, while PAU was more likely to be found incidentally in older patients with atherosclerosis. Endovascular therapy was effective in both IMH and PAU patients with encouraging outcomes.

Computed Tomography Angiography Assessment of Acute Aortic Syndromes: Classification, Differentiating Imaging Features, and Imaging Interpretation Pitfalls

An acute aortic syndrome (AAS) is an important life-threatening condition that requires early detection and management. Acute intramural hematoma (IMH), aortic dissection (AD) and penetrating atherosclerotic ulcer (PAU) are included in AAS. ADs can be classified using the well-known Stanford or DeBakey classification systems. However, these classification systems omit description of arch dissections, anatomic variants, and morphologic features that impact outcome. The Society for Vascular Surgery and Society of Thoracic Surgeons (SVS-STS) have recently introduced a classification system that classifies ADs according to the location of the entry tear (primary intimomedial tear, PIT) and the proximal and distal extent of involvement, but does not include description of all morphologic features that may have diagnostic and prognostic significance. This review describes these classification systems for ADs and other AAS entities as well as their limitations. Typical computed tomography angiography (CTA) imaging appearance and differentiating features of ADs, limited intimal tears (LITs), IMHs, intramural blood pools (IBPs), ulcer-like projections (ULPs), and PAUs will be discussed. Furthermore, this review highlights common imaging interpretation pitfalls, what should be included in a comprehensive CTA report, and provides a brief overview of current management options.

Demystifying penetrating atherosclerotic ulcer of aorta: unrealised tyrant of senile aortic changes

This review article describes demographic features, comorbidities, clinical and imaging findings, prognosis, and treatment strategies in penetrating atherosclerotic ulcer (PAU) and closely related entities using google scholar web search. PAU is one of the manifestations of the acute aortic syndrome (AAS) spectrum. The underlying aorta invariably shows atherosclerotic changes or aneurysmal dilatation. Hypertension is the most common contributing factor, with chest or back pain being the usual manifestation. Intramural hematoma (IMH) is the second entity associated with both PAU and aortic dissection (AD), more so with the latter. Chest radiograph can show mediastinal widening, pleural, or pericardial fluid in rupture. Computed tomography angiography (CTA) is the imaging modality of choice to visualize PAU, with magnetic resonance imaging (MRI) and transoesophageal echocardiography (TEE) adding diagnostic value. Lesser-known entities of intramural blood pool (IBP), limited intimal tears (LITs), and focal intimal disruptions (FID) are also encountered. PAU can form fistulous communication with adjacent organs whereas IMH may propagate to dissection. CTA aids in defining the management, open or endovascular options in surgical candidates.

Non-traumatic thoracic aortic emergencies: imaging diagnosis and management

The major component of non-traumatic thoracic aortic emergencies is the acute aortic syndromes. These include acute aortic dissection, intramural haematoma and penetrating atherosclerotic ulcer, grouped together because they are indistinguishable clinically and highly fatal. All three entities involve disruption to the tunica intima and media and may be complicated by rupture, end-organ ischaemia or aneurysmal transformation. Early diagnosis is vital to allow timely and appropriate management. Paired unenhanced and electrocardiogram-gated computed tomography angiography of the chest, extending more distally if required, is recommended for diagnosis. Specific computed tomography features of all three entities are reviewed, with a focus on morphological features associated with complications. Those with type A pathology are usually managed with open surgery because this has a high risk of complication. Patients with uncomplicated type B pathology are usually managed with best medical therapy whereas those with complicated type B pathology are usually offered either surgery or thoracic endovascular aortic repair. The limited evidence regarding the use of thoracic endovascular aortic repair in patients with subacute uncomplicated type B pathology is briefly discussed.

Detection of the intimal tear in aortic dissection and ulcer-like projection in intramural hematoma: usefulness of full-phase retrospective ECG-gated CT angiography

PURPOSE

To compare the accuracy of non-electrocardiogram (ECG)-gated CT angiography (CTA), single-diastolic-phase ECG-gated CTA, and full-phase ECG-gated CTA in detecting the intimal tear (IT) in aortic dissection (AD) and ulcer-like projection (ULP) in intramural hematoma (IMH).

MATERIALS AND METHODS

A total of 81 consecutive patients with AD and IMH of the thoracic aorta were included in this single-center retrospective study. Non-ECG-gated CTA, single-diastolic-phase ECG-gated CTA, and full-phase ECG-gated CTA were used to detect the presence of the IT and ULP in thoracic aortic regions including the ascending aorta, aortic arch, and proximal and distal descending aorta.

RESULTS

The accuracy of detecting the IT and ULP was significantly greater using full-phase ECG-gated CTA (88% [95% CI: 100%, 75%]) than non-ECG-gated CTA (72% [95% CI: 90%, 54%], P = 0.001) and single-diastolic-phase ECG-gated CTA (76% [95% CI: 93%, 60%], P = 0.008).

CONCLUSION

Full-phase ECG-gated CTA is more accurate in detecting the IT in AD and ULP in IMH, than non-ECG-gated CTA and single-diastolic-phase ECG-gated CTA.

Acute type A aortic intramural hematoma and type A aortic dissection: correlation between the intimal tear features and pathogenesis

Background

To determine the prevalence, clinical and imaging features of intimal tear detected by ECG-gated multidetector computed tomography (MDCT) and confirmed by surgery in patients with acute type A intramural hematoma (ATAIMH) and acute type A aortic dissection (AAAD).

Methods

This retrospective study involved analysis of the intimal tear characteristics in 72 consecutive patients with ATAIMH and 209 with AAAD who were diagnosed by MDCT. The size and location of the intimal tear were measured and compared between these two groups of patients. The findings were also compared with those from 28 patients with ATAIMH who underwent surgical treatment to determine the intimal tear features as observed on CT angiography (CTA).

Results

Patients in the ATAIMH group were significantly older than those in the AAAD group (58.6±11.3 vs. 49.4±12.8 years, P<0.001), and females were predominant in the former category (ATAIMH vs. AAAD: 44.4% vs. 27.8%, P<0.01). Marfan syndrome and pregnancy were associated with most of the occurrences of AAAD. Sixty-four patients (88.9%) with ATAIMH were recognized as having intimal tear in the CTA images. The number of aortic segments in the ATAIMH patients was smaller than that in the AAAD patients (4.45±1.56 vs. 5.04±1.72 segments, P<0.01). The distribution of the intimal tear did not show any difference between the two groups. During the surgery, pericardial hemorrhage was observed in a higher proportion of patients in the ATAIMH than in the AAAD group (60.7% vs. 22.1%; P<0.01). In the former category, all of the intimal tears detected using CTA were confirmed during the operation, and the size was significantly larger than measured on the CTA images (6.95±5.12 vs. 19.59±6.51 mm, P<0.001). Six ATAIMH patients progressed to classical aortic dissection (AD) at surgery.

Conclusions

Patients with ATAIMH have a high prevalence of intimal tear, which is significantly smaller than that measured in patients with classic AAAD. Just like AD, ATAIMH may also be triggered by intimal tear. Hence, timely surgical repair is needed.

Diagnosing Aortic Intramural Hematoma: Current Perspectives

Aortic intramural hematoma (AIH) is an entity within the acute aortic syndrome. Combination of a priori probability, clinical history, laboratory blood test and imaging techniques are the basis for diagnosis of AIH. This review is focused on all aspects related to diagnosis of patients with AIH, from clinical to imaging and analytical.

Updates on Computed Tomography Imaging in Aortic Aneurysms and Dissection

Computed tomography (CT) is a primary imaging modality for the diagnosis of aortic diseases, because of its minimal invasiveness and agility.

Prompt and accurate diagnosis is crucial especially for acute aortic diseases, and the guidelines for acute aortic dissection recommend the use of CT for initial diagnosis. For the follow-up observation of longstanding aortic diseases, the strategy of imaging management by CT must be different from that for emergency and acute phases.

In this review, we document the differences in characteristics and clinical course between aortic aneurysm and aortic dissection and explain the use of recent CT techniques in diagnosing short- and longstanding aortic diseases.

Intramural hematoma and penetrating ulcer in the descending aorta: differences and similarities

Acute aortic syndromes include a variety of overlapping clinical and anatomic diseases. Intramural hematoma (IMH), penetrating atherosclerotic ulcer (PAU), and aortic dissection can occur as isolated processes or can be found in association. All these entities are potentially life threatening, so prompt diagnosis and treatment is of paramount importance. IMH and PAU affect patients with atherosclerotic risk factors and are located in the descending aorta in 60-70% of cases. IMH diagnosis can be correctly made in most cases. Aortic ulcer is a morphologic entity which comprises several entities-the differential diagnosis includes PAU, focal intimal disruptions (FID) in the context of IMH evolution and ulcerated atherosclerotic plaque. The pathophysiologic mechanism, evolution and prognosis differ somewhat between these entities. However, most PAU are diagnosed incidentally outside the acute phase. Persistent pain despite medical treatment, hemodynamic instability, maximum aortic diameter (MAD) >55 mm, significant periaortic hemorrhage and FID in acute phase of IMH are predictors of acute-phase mortality. In these cases, TEVAR or open surgery should be considered. In non-complicated IMH or PAU, without significant aortic enlargement, strict control of cardiovascular risk factors and frequent follow-up imaging appears to be a safe management strategy.

CT imaging of complications of aortic intramural hematoma: a pictorial essay

Aortic intramural hematoma (IMH) is a pathologic process with a clinical presentation identical to aortic dissection and associated with significant morbidity and mortality. Radiologists must be familiar with the imaging appearances of IMH as computed tomography (CT) plays a critical role in both diagnosis and patient management. The course of IMH is variable and the process may regress, remain stable, or progress in extent and therefore imaging findings associated with a negative prognosis must be recognized and included in the formal radiology report. Potentially life-threatening complications and findings associated with IMH include hemopericardium and cardiac tamponade, coexisting aortic dissection, ulcer-like projection, intramural blood pool, and extension of hematoma along the pulmonary or coronary arteries, which are identifiable with aortic protocol CT. The purpose of this pictorial review is to provide the reader with an image-based review of the diagnostic criteria, related complications, and associated critical prognostic features in patients presenting with aortic IMH.

Analysis of Risk Factors for Aortic Enlargement in Patients with Chronic Type B Aortic Dissection

Objectives: Uncomplicated type B aortic dissection is generally treated with medical management including antihypertensive therapy. The purpose of this study is to investigate risk factors associated with the aortic enlargement in medically treated patients. Methods: Between July 2004 and April 2016, 127 consecutive patients with acute type B aortic dissection were treated in our institution. Of these, 104 patients diagnosed with uncomplicated type B dissection were managed medically as an initial treatment. According to the diameter of the dissected aorta, these patients were retrospectively placed into 2 groups: 1) enlargement group (group E: n=36); and 2) unchanged group (group U: n=68). Results: There was statistically significant difference regarding the initial diameter of the dissected aorta (group E: 42±7 mm, group U: 36±7 mm) (p<0.01). As regards the aneurysm growth rate, a significant difference between both groups was noted (group E: 10±32 mm/half-year, group U -3±19 mm/half-year) (p<0.05). In all 104 patients, 42 patients (40.4%) had patent false lumen with the average number of 1.5 intimal tears. Multivariate analysis showed the relationship for aortic enlargement were patent false lumen (p<0.05, 95%CI 0.407-0.935) and initial aortic diameter (p<0.01, 95%CI 1.076-1.158). Aortic event free survival (1/5/10 years) was 100/86/77% in group E and 92/79/79% in group U, respectively no differences between two groups (p=0.747). Conclusions: The medically managed patients with uncomplicated chronic type B dissection showed excellent survival rate during long-term follow-up. The results of surgical or endovascular treatment in patients underwent initial medical therapy were also satisfactory. The patent false lumen and aortic diameter at the onset may impact on aortic enlargement. Considering our results, the feasibility of elective endovascular repairs in stable dissection remains controversial even in the endovascular era. (This is a translation of Jpn J Vasc Surg 2018; 27: 55-60.).

Classification of spontaneous isolated superior mesenteric artery dissection: correlation with multi-detector CT features and clinical presentation

PURPOSE

The purpose of the study is to propose a computed tomography (CT) classification of spontaneous isolated superior mesenteric artery dissection (SISMAD) correlated with clinical presentation METHODS: We retrospectively reviewed CT images of 40 patients with SISMAD at our institution from 2006 to 2015 and proposed a new classification: type I, patent false lumen with both entry and re-entry; type II, patent false lumen without re-entry; type III, completely or partially thrombosed false lumen; and type IV, thrombosed false lumen with ulcer-like projection. Additionally, we included a subtype (S) at each type when there was either a long segment of dissection and/or significant true lumen stenosis. CT features were statistically analyzed using Fisher's exact and Mann-Whitney test.

RESULTS

The CT findings classified patients as type I (15%), type II (12.5%), type III (35%), and type IV (37.5%). Of the 40 patients, 25 (62.5%) were symptomatic. There was a significantly different proportion of each type between symptomatic and asymptomatic patients (p = 0.005). There were 25 patients with subtype (S); no type I or II, 12 type III, and 13 type IV. The symptomatic patients showed longer dissection tendency and more severe true lumen stenosis (78% vs. 53%, p = 0.000) compared with asymptomatic patients.

CONCLUSION

The proposed multi-detector CT classification of SISMAD correlates with clinical presentation. This new classification could be helpful for treatment planning.

Update on the Therapeutic Strategy of Type B Aortic Dissection

Stanford type B aortic dissection (TBAD) is a life-threatening disease. Current therapeutic guidelines recommend medical therapy with aggressive blood pressure lowering for patients with acute TBAD unless they have fatal complications. Although patients with uncomplicated TBAD have relatively low early mortality, aorta-related adverse events during the chronic phase worsen the long-term clinical outcome. Recent advances in thoracic endovascular aortic repair (TEVAR) can improve clinical outcomes in patients with both complicated and uncomplicated TBAD. According to present guidelines, complicated TBAD patients are recommended for TEVAR. However, the indication in uncomplicated TBAD remains controversial. Recent results of randomized trials, which compared the clinical outcome in patients treated with optimal medical therapy and those treated with TEVAR, suggest that preemptive TEVAR should be considered in uncomplicated TBAD with suitable aortic anatomy. However, these trials failed to show improvement in early mortality in patients treated with TEVAR compared with patients treated with optimal medical therapy, which suggest the importance of patient selection for TEVAR. Several clinical and imaging-related risk factors have been shown to be associated with early disease progression. Preemptive TEVAR might be beneficial and should be considered for high-risk patients with uncomplicated TBAD. However, an interdisciplinary consensus has not been established for the definition of patients at high-risk of TBAD, and it should be confirmed by experts including physicians, radiologists, interventionalists, and vascular surgeons. This review summarizes the current understanding of the therapeutic strategy in patients with TBAD based on evidence and expert consensus.

Ulcer like projection: a case report and follow up

Here we report the case of a 57-year-old female with an aortic intramural hematoma that was treated with medical approach. Follow confirmed the favorable clinical evolution.

An analysis of initial and follow-up CT findings in intramural hematoma, aortic double-lumen dissection, and mixed type lesions

BACKGROUND

Although the clinical presentation of intramural hematoma (IMH) and aortic double-lumen dissection (AD) is similar, the imaging results and subsequent clinical course of the two lesions differ.

PURPOSE

To compare the clinical and radiological findings of IMH, AD, and mixed type lesions.

MATERIAL AND METHODS

Forty-two patients with IMH, 38 with AD, and 10 with mixed type lesions were imaged with post-contrast-enhanced CT. The most proximal ulcer-like lesions and entry tears and the distal ends of the IMH and AD were evaluated. The interval change of the intramural hematoma, ulcer-like lesion, and false lumen was observed. The pathological findings of the aorta were evaluated in 15 patients.

RESULTS

The most proximal ulcer-like lesion and entry tear were located in the arch to the descending aorta in 27 (64.2%) of the 42 patients with IMH and in 24 (63.1%) of the 38 patients with AD. The distal extension was located at the iliac arteries in six (14.3%) patients with IMH and in 31 (81.6%) patients with AD (P < 0.001). The intramural hematomas regressed in 29 (93.5%) of 31 patients, and the ulcer-like lesion progressed in 14 (70%) of 20 patients with IMH. The clinical features of the mixed type lesions resembled those of AD, rather than IMH. The intramural hematoma or dissection was observed within the outer media in all lesion types on histopathology.

CONCLUSION

There is a distinct difference between IMH and AD in distal extension; however, the locations of the lesions are pathologically the same in the media of the aorta.

Midterm results of type B intramural hematoma endovascular treatment

BACKGROUND

Recently, intramural hematoma (IMH) has been characterized as a rare variant of aortic dissection, falling within the acute aortic syndromes (AAS). Although aortic endovascular treatment seems to provide good results, no consensus has been established regarding the optimal management of IMH affecting the descending thoracic aorta (IMH B). The aim of this study was to assess long-term clinical and morphological results of IMH B treated with a stent graft.

METHODS

Between 2002 and 2013, 15 of the 423 (3.5%) consecutive patients with AAS were found to have IMH B. During follow-up, complications related to IMH B were observed in 10 patients, including 5 during the acute period (<14 days). Surgical indications were ulcerations, refractory pain, aneurysm evolution, aortic rupture, and pleural effusion. An endovascular approach was taken for all forms with suitable anatomy.

RESULTS

Technical success rate was 100%, with complete exclusion of lesions of the descending thoracic aorta in all cases treated with a stent graft. No neurological complications or deaths occurred within the first 30 postoperative days, nor at the end of the mean follow-up of 46 months (1-137 months). After the aortic stent graft, partial or complete regression of the hematoma was observed in all cases.

CONCLUSIONS

IMH B is most often a progressive disease requiring long-term monitoring. In case of complications, stent-graft treatment of the descending thoracic aorta can be performed successfully in most cases. This procedure appears to be a safe technique that provides very good long-term results, with favorable remodeling of the aorta.

Endovascular repair of aortic dissection and intramural hematoma: indications and serial changes

Thoracic aortic dissection (AD) is one of the most common aortic emergencies. It can be fatal if not promptly diagnosed and treated. Intramural hematoma (IMH) of the aorta is recognized as distinct from classic (double-barreled) AD. IMH also frequently leads to aortic emergency, which can be fatal unless rapidly diagnosed and treated. Recently, thoracic endovascular aortic repair (TEVAR) has been used for the treatment of complications caused by AD. TEVAR is also a viable option for the treatment of complicated IHM. In this article, we review the details of TEVAR as treatment options for AD and IMH, including the indications for TEVAR, imaging, and follow-up.

MDCT distinguishing features of focal aortic projections (FAP) in acute clinical settings

Focal aortic projections (FAP) are protrusion images of the contrast medium (focal contour irregularity, breaks in the intimal contour, outward lumen bulging or localized blood-filled outpouching) projecting beyond the aortic lumen in the aortic wall and are commonly seen on multidetector computed tomography (MDCT) scans of the chest and abdomen. FAP include several common and uncommon etiologies, which can be demonstrated both in the native aorta, mainly in acute aortic syndromes, and in the post-surgical aorta or after endovascular therapy. They are also found in some types of post-traumatic injuries and in impending rupture of the aneurysms. The expanding, routine use of millimetric or submillimetric collimation of current state-of-the-art MDCT scanners (16 rows and higher) all the time allows the identification and characterization of these small ulcer-like lesions or irregularities in the entire aorta, as either an incidental or expected finding, and provides detailed three-dimensional pictures of these pathologic findings. In this pictorial review, we illustrate the possible significance of FAP and the discriminating MDCT features that help to distinguish among different types of aortic protrusions and their possible evolution. Awareness of some related and distinctive radiologic features in FAP may improve our understanding of aortic diseases, provide further insight into the pathophysiology and natural history, and guide the appropriate management of these lesions.

Current understandings and approach to the management of aortic intramural hematomas

Intramural hematoma is the most enigmatic of the 3 lethal entities comprising acute aortic syndrome. Despite being identified almost 100 years ago, there is considerable controversy surrounding the definition, etiology, management, and the very existence of intramural hematoma. The following review outlines these controversies and discusses their effect on management strategies.

Multi-detector computed tomography in the diagnosis and management of acute aortic syndromes

Acute aortic syndrome (AAS) is a spectrum of conditions, which may ultimately progress to potentially life-threatening aortic rupture. This syndrome encompasses aortic dissection (AD), intramural haematoma, penetrating atherosclerotic ulcer and unstable thoracic aortic aneurysms. Multi-detector CT (MDCT) is crucial for the diagnosis of AAS, especially in the emergency setting due to its speed, accuracy and ready availability. This review attends to the value of appropriate imaging protocols in obtaining good quality images that can permit a confident diagnosis of AAS. AD is the most commonly encountered AAS and also the one with maximum potential to cause catastrophic outcome if not diagnosed and managed promptly. Hence, this review briefly addresses certain relevant clinical perspectives on this condition. Differentiating the false from the true lumen in AD is often essential; a spectrum of CT findings, e.g., “beak sign”, aortic “cobwebs” that allows such differentiation have been described with explicit illustrations. The value of non enhanced CT scans, especially useful in the diagnosis of an intramural hematoma has also been illustrated. Overlap in the clinical and imaging features of the various conditions presenting as AAS is not unusual. However, on most instances MDCT enables the right diagnosis. On select occasions MRI or trans-esophageal echocardiography may be required as a problem solving tool.

Endovascular treatment of an acute ascending aortic intramural hematoma

INTRODUCTION

Herein, we present a case of an elderly gentleman who presented with an extensive intramural hematoma of the aorta which was treated with a percutaneous placement of an endovascular stent.

PRESENTATION OF CASE

A 79-year-old male with a history of hypertension presented to the emergency department because of sudden onset of substernal chest pain radiating to his back. A chest computerized tomography scan was performed that demonstrated a Type A aortic wall intramural hematoma involving the arch and ascending aorta dissecting both antegrade and retrograde from a penetrating ulcer located in the descending aorta, immediately distal to the left subclavian artery. No dissection flap was noted. The patient opted for an endovascular approach. He was treated with the placement of a stent just distal to the left subclavian artery, with good results noted on follow-up exam performed 3 months later.

DISCUSSION

The treatment of a Type A IMH lacks consensus, but the majority do favor surgical management. The data are limited; however, there are reports of patients with Type A intramural hematoma treated with descending aortic endograft at the site of the culprit ulcerated plaque, with satisfactory results.

CONCLUSION

In a select group of patients, an endovascular approach for the treatment of a Type A aortic wall intramural hematoma caused by an ulcerated plaque may be a viable treatment option.

Conservatively treated Type B intramural hematoma: Progression into acute aortic dissection followed by spontaneous resolution, assessed by CT

This case report shows the full spectrum evolution of type B intramural hematoma under conservative treatment, with initial progression into a true aortic dissection, followed by extremely rare near-complete healing of the dissection at followup.

Treatment of acute type-B aortic dissection: thoracic endovascular aortic repair or medical management alone?

OBJECTIVES

This study sought to evaluate the early and long-term effect of thoracic endovascular aortic repair (TEVAR) on type-B acute aortic dissection (AAD).

BACKGROUND

Uncomplicated type-B AAD is generally treated with medical management; complicated dissections require surgery or TEVAR. Studies have demonstrated that long-term outcomes with medical management are suboptimal. Therefore, we sought to determine the long-term effect of TEVAR compared with medical management alone on type-B AAD.

METHODS

From January 2004 to May 2008, 193 consecutive patients in 2 hospitals were treated and retrospectively placed into 1 of 2 groups: 1) the TEVAR group-type-B AAD treated with TEVAR and antihypertensive medications (n = 152); and the 2) medicine group-uncomplicated type-B AAD treated medically alone (n = 41). All TEVAR procedures were performed in the acute phase.

RESULTS

There were no significant differences in demographics, comorbidity profiles, or early events between groups. The cumulative freedom from all late adverse events at 1, 3, and 5 years was 97%, 89%, and 67% in the TEVAR group and 97%, 63%, and 34% in the medicine group. Log-rank tests showed that medically treated patients had more late adverse events than TEVAR-treated patients did (p = 0.003). The 5-year cumulative survival rate from all-cause death was not significantly different between the 2 groups.

CONCLUSIONS

Patients with type-B AAD treated with TEVAR experienced fewer late adverse events than those treated with medical management, but there was no significant difference among the groups in 5-year mortality rates. Further studies of longer-term survival rates are needed to determine whether TEVAR could be an effective treatment for type-B AAD.