Aortic remodeling after thoracic endovascular aortic repair for intramural hematoma

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.

Five Year Results of Endovascular versus Medical Therapy in Acute Type B Aortic Intramural Haematoma: Meta-Analysis of Reconstructed Time to Event Data

OBJECTIVE

To evaluate outcomes in the follow up of thoracic endovascular aortic repair (TEVAR) vs. medical therapy in patients with acute type B aortic intramural haematoma (IMH).

DATA SOURCES

The following sources were searched for articles meeting the inclusion criteria and published by July 2023: PubMed/MEDLINE, EMBASE, CENTRAL/CCTR (Cochrane Controlled Trials Register).

REVIEW METHODS

This systematic review with pooled meta-analysis of time to event data followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines, and its protocol was registered on the public platform PROSPERO (CRD42023456222). The following were analysed: overall survival (all cause mortality), aortic related mortality, and restricted mean survival time. Certainty of evidence was evaluated through the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) tool.

RESULTS

Eight studies met the eligibility criteria, including 1 015 patients (440 in the TEVAR group and 575 in the medical therapy group). All studies were observational, and the pooled cohort had a median follow up of 5.1 years. Compared with patients who received medical therapy alone, those who underwent TEVAR had a statistically significantly lower risk of all cause death (HR 0.44, 95% CI 0.30 - 0.65; p < .001; GRADE certainty: low), lower risk of aortic related death (HR 0.04, 95% CI 0.01 - 0.31; p = .002; GRADE certainty: low) and lifetime gain (restricted mean survival time was overall 201 days longer with TEVAR; p < .001).

CONCLUSION

Thoracic endovascular aortic repair may be associated with lower risk of all cause and aortic related death compared with medical therapy in patients with acute type B IMH; however, the underlying data are not strong enough to draw robust clinical conclusions. Randomised controlled trials with large sample sizes and longer follow up are warranted to elucidate this question.

The Role of Endovascular Repair Timing in Uncomplicated Acute Type B Intramural Hematoma Management

BACKGROUND

With favorable results of thoracic endovascular aortic repair (TEVAR) in patients with uncomplicated acute type B intramural hematoma (uTBIMH), TEVAR is increasingly utilized in the management of patients with uTBIMH. However, optimal timing for intervention has not been decided. This study aimed to compare the efficacy of acute and delayed TEVAR in patients with uTBIMH.

METHODS

We included patients with uTBIMH who underwent TEVAR between October 2014 and December 2021. The participants were divided into the acute TEVAR (aTEVAR) and delayed TEVAR (dTEVAR) groups. We analyzed the total aortic diameter (TAD)/true lumen diameter (TLD) ratio on computed tomography angiography (CTA) and aortic-related adverse events and all-cause mortality (AREM).

RESULTS

We included 34 individuals with uTBIMH, among which 20 underwent aTEVAR and 14 underwent dTEVAR. We observed no significant differences in baseline characteristics between both groups. However, compared with the aTEVAR group, better aortic remodeling was achieved in the dTEVAR group before discharge (1.32 ± 0.11 vs. 1.21 ± 0.09, P = 0.005) and at the 1-year follow-up (1.18 ± 0.09 vs. 1.10 ± 0.04, P = 0.034). Although the 30-day and 1-year follow-up outcomes of AREM were not significantly different, the Kaplan-Meier analysis showed that AREM incidence in the dTEVAR group was significantly lower than that in the aTEVAR group (85.7% for dTEVAR vs. 65.0% for aTEVAR, log-rank P = 0.20). Moreover, subgroup analysis revealed a significant difference in the TAD/TLD ratio between the aTEVAR and dTEVAR groups in individuals without a focal intimal disruption (1.33 ± 0.11 vs. 1.17 ± 0.09, P = 0.008).

CONCLUSIONS

For individuals with uTBIMH, delaying TEVAR by >7 days improved aortic remodeling and lowered the incidence of early AREM. Additionally, the absence of focal intimal disruption on preoperative CTA supports delayed intervention.

Impact of post-implantation syndrome on outcomes in acute type B aortic syndrome patients undergoing endovascular repair

Background: The aim of this study was to explore the impact of post-implantation syndrome (PIS) on prognosis outcomes in individuals with type B acute aortic syndrome (AAS) undergoing thoracic endovascular aortic repair (TEVAR). Patients and methods: Data from type B AAS individuals who underwent TEVAR from January 2014 to April 2021 were retrospectively reviewed. Study subjects were divided into PIS and non-PIS (nPIS) groups and postoperative clinical outcomes were analyzed. Results: Our study cohort of 74 individuals with type B AAS included 40 aortic dissection (AD), 30 intramural hematoma (IMH), 4 penetrating aortic ulcer (PAU). The incidence of PIS was 14.9%. No statistically significant differences were found in baseline characteristics. The left subclavian artery (LSCA) reconstruction was performed more frequently among the PIS group (45.5% vs 9.5%, p=.008). Major adverse events (MAE) tended to be more frequent in the PIS group, but the difference was not significant (27.3% vs 22.2%, p=.707). At 2-year follow-up, results were comparable between the two groups. Kaplan-Meier analysis showed that PIS was not associated with a higher incidence of mortality, endoleak, new-onset AD, or stroke. A baseline neutrophil-to-lymphocyte ratio (NLR) >10.3 was associated with greater incidence of MAE. In individuals with IMH, better aortic remodeling evaluated by lower total aortic diameter/true lumen diameter (TAD/TLD) was achieved in the nPIS group (1.23±0.10 vs 1.43±0.07, p<.001), and a TAD/TLD ratio >1.32 was associated with significantly more MAE. Cox multivariate regression analysis also showed that a postoperative TAD/TLD ratio >1.32 was an independent risk factor for MAE (OR, 11.36; 95% CI, 1.53-84.26; p=.017). Conclusions: PIS was associated with a trend toward a higher incidence of MAE after TEVAR. In individuals with IMH, a TAD/TLD ratio >1.32 was an independent predictor of postoperative MAE.

Thoracic Endovascular Aortic Repair versus Optimal Medical Treatment in Patients with Type B Intramural Hematoma: A Meta-Analysis

PURPOSE

We intended to study the effect of thoracic endovascular aortic repair (TEVAR) and optimal medical treatment (OMT) on type B intramural hematoma (BIMH).

METHODS

We searched PubMed, EMbase, Cochrane Library, and China National Knowledge Infrastructure databases that compared TEVAR and OMT in patients with BIMH. Two authors independently assessed the risk of bias using the Newcastle-Ottawa Scale. The rate ratio (RR) and 95% confidence interval were used to calculate the outcome. The primary endpoints were aortic-related death and regression/resolution. Secondary endpoints were all-cause death, progression to dissection, and secondary intervention.

RESULTS

Eight observational studies were included in the analysis. TEVAR reduced aortic-related death (RR 0.22, 95% CI 0.08-0.56, P = 0.002, I² = 24%) and promoted hematoma regression/resolution (RR 1.48, 95% CI 1.05-2.10, P <0.05, I² = 71%) compared to OMT. Moreover, TEVAR was associated with a reduction in progression to dissection (RR 0.32, 95% CI 0.13-0.81, P <0.02, I² = 39%) and secondary intervention (RR 0.18, 95% CI 0.09-0.37, P <0.00001, I² = 38%) compared to OMT. However, all-cause death has no significant difference between the two groups (RR 0.45, 95% CI 0.17-1.19, P = 0.11, I² = 58%).

CONCLUSIONS

The results of this meta-analysis suggested that TEVAR is an effective treatment for BIMH, which can delay the progression of intramural hematoma and promotes regression/resolution. More research about indications of TEVAR is still needed.

Management of penetrating aortic ulcer and intramural hematoma in the thoracic aorta

Acute aortic syndrome is a broad clinical entity that encompasses several pathologies. Aortic dissection is a well-studied disorder, but the other most prominent disorders within the scope of acute aortic syndrome, penetrating aortic ulcer and intramural hematoma, are more nebulous in terms of their pathophysiology and treatment strategies. While patient risk factors, presenting symptoms, and medical and surgical management strategies are similar to those of aortic dissection, there are indeed nuanced differences unique to penetrating aortic ulcer and intramural hematoma that surgeons and acute care providers must consider while managing patients with these diagnoses. The aim of this review is to summarize patient demographics, pathophysiology, workup, and treatment strategies that are unique to penetrating aortic ulcer and intramural hematoma.

Acute aortic syndromes: a review of what we know and future considerations

Acute aortic syndromes represent a spectrum of life-threatening aortic pathologies. Prompt diagnosis and proper management of these syndromes are important in reducing overall mortality and morbidity, which remains high. Acute aortic dissections represent most of these aortic wall pathologies, but intramural haematomas and penetrating atherosclerotic ulcers have been increasingly diagnosed. Type A dissections require prompt surgical treatment, with endovascular options on the horizon. Type B dissections can be complicated or uncomplicated, and treatment is determined based on this designation. Complicated Type B dissections require prompt repair with thoracic endovascular aortic repair (TEVAR) becoming the preferred method. Uncomplicated Type B dissections require medical management, but early TEVAR in the subacute setting is becoming more prominent. Proper surveillance for an uncomplicated Type B dissection is crucial in detecting aortic degeneration and need for intervention. Intramural haematomas and penetrating atherosclerotic ulcers are managed similarly to aortic dissections, but more research is needed to determine the proper management algorithms. Multi-disciplinary aortic programmes have been shown to improve patient outcomes and are necessary in optimizing long-term follow-up.

IMPACT OF THORACIC ENDOVASCULAR AORTIC REPAIR TIMING ON AORTIC REMODELING IN ACUTE TYPE B AORTIC INTRAMURAL HEMATOMA

INTRODUCTION

Thoracic endovascular aortic repair (TEVAR) is increasingly utilized in the management of acute type B aortic intramural hematoma (TBIMH). Optimal timing for intervention has not been described. The aim of this study was to evaluate TEVAR timing on post-operative aortic remodeling.

METHODS

A retrospective chart review was performed on patients who underwent TEVAR for TBIMH from January 2008 to September 2018. Imaging was reviewed pre- and postoperatively. Primary data points included true lumen diameter (TLD) and total aortic diameter (TAD) at the site of maximal pathology. Primary endpoint was aortic remodeling evidenced by a TAD/TLD ratio closest to 1.0. Secondary outcome was occurrence of aortic-related adverse events and mortality (AREM): aortic rupture, aortic-related death, progression to dissection or need for aortic re-intervention within 12 months. Patients undergoing emergent TEVAR (within 24 hours, 'eTEVAR') were compared to the remainder - delayed TEVAR ('dTEVAR').

RESULTS

We analyzed 71 patients that underwent TEVAR FOR TBIMH; 25 underwent emergent TEVAR and 46 patients underwent dTEVAR (median: 5.5 days, range: 2-120 days). There were no differences in demographics and comorbidities and patients did not differ in presenting IMH thickness (12.6±3.1 mm vs. 11.3±4.1 mm, p=0.186) nor presenting TAD/TLD ratio (1.535±0.471 vs. 1.525±0.397, p=0.928) for eTEVAR and dTEVAR groups, respectively. eTEVAR patients had larger average presenting maximal descending aortic (DTA) diameter (45.8±14.3 mm vs. 38.2±7.5 mm, p=0.018) and higher incidence of penetrating aortic ulcer (PAU) on presenting CT angiography (52.0% vs 21.7%, p=0.033). Thirty day mortality was 2/25 (8.0%) for eTEVAR and 2/45 (4.4%) for dTEVAR (p=0.602). Postoperative aortic remodeling was more complete in the dTEVAR group (1.23±0.12 vs. 1.33±0.15, p=0.004). Case-control matching (controlling for presenting DTA diameter and PAU) on 30 patients still showed better aortic remodeling in the dTEVAR group (1.125±0.100 vs 1.348±0.42, p<0.001). The incidence of AREM was higher in the eTEVAR - 6/25 (24.0%) - group compared to the dTEVAR group - 2/46 (4.3%). At 12 months, freedom from AREM was higher in the dTEVAR group (95.7% vs. 76.0%, p=0.011). Postoperative TAD/TLD ratio was the best predictor for late aortic-related adverse events (AUROC=0.825, p=0.003).

CONCLUSION

TEVAR for acute type B IMH within 24 hours of admission is associated with lower aortic remodeling and higher occurrence of late aortic related adverse events and mortality. Delaying TEVAR when clinically possible could improve aortic remodeling and aortic-related outcomes.

Clinical outcomes of endovascular treatment for ruptured thoracic aortic disease

BACKGROUND/AIMS

Untreated rupture of the thoracic aorta is associated with a high mortality rate. We aimed to review the clinical results of endovascular treatment for ruptured thoracic aortic disease.

METHODS

We retrospectively reviewed data on 37 patients (mean age, 67.0 ± 15.18 years) treated for ruptured thoracic aortic disease from January 2005 to May 2016. The median follow-up duration was 308 days (interquartile range, 61 to 1,036.5). The primary end-point of the study was the composite of death, secondary intervention, endoleak, and major stroke/paraplegia after endovascular treatment.

RESULTS

The etiologies of ruptured thoracic aortic disease were aortic dissection (n = 11, 29.7%), intramural hematoma (n = 7, 18.9%), thoracic aortic aneurysm (n = 14, 37.8%), and traumatic aortic transection (n = 5, 13.5%). Three patients died within 24 hours of thoracic endovascular aortic repair, and one showed type I endoleak. The technical success rate was 89.2% (33/37). The in-hospital mortality rate was 13.5% (5/37); no deaths occurred during follow-up. The composite outcome rate during follow-up was 37.8% (14/37), comprising death (n = 5, 13.5%), secondary intervention (n = 5, 13.5%), endoleak (n = 5, 13.5%), and major stroke/paraplegia (n = 3, 8.1%). Left subclavian artery revascularization and proximal landing zone were not associated with the composite outcome. Low mean arterial pressure (MAP; ≤ 60 mmHg, [hazard ratio, 13.018; 95% confidence interval, 2.435 to 69.583, p = 0.003]) was the most significant predictor and high transfusion requirement in the first 24 hours was associated with event-free survival (log rank p = 0.018).

CONCLUSION

Endovascular treatment achieves high technical success rates and acceptable clinical outcome. High transfusion volume and low MAP were associated with poor clinical outcomes.

Is the Natural Anatomical Evolution of Type B Intramural Hematomas Reliable to Identify the Patients at Risk of Aneurysmal Progression?

BACKGROUND

The natural history of type B intramural hematomas is little-known. Aneurysmal progression or an aortic dissection occurs in 15 to 20% of the cases. The study of the natural anatomical evolution could help identify the patients at risk of unfavorable evolution.

METHODS

All the patients monitored for a type B intramural hematoma between 2009 and 2018 were included in this monocentric retrospective study. Computed tomography angiography centerline measurement of diameters was obtained in various points of aortic segmentation on day (D) 0 and at one month (M1). Aortic volumes (lumen, intramural hematoma, and total volume) were calculated. The circulating volume was calculated using the volume rendering method. The volume of the intramural hematoma was measured using a manual section-by-section segmentation tool, and the total volume was obtained by summing up the two preceding volumes. Two groups of patients were compared: group 1 (favorable anatomical evolution) and group 2 (unfavorable anatomical evolution).

RESULTS

Between January 2008 and August 2018, 25 patients were managed for a type B intramural hematoma in our center. After an average follow-up of 15.5 months (1-52), 13 patients (52%) presented a favorable evolution and 12 (48%) an unfavorable evolution. At M1, a significant increase of the luminal diameters (37 mm vs. 32 mm; P < 0.01) and a significant reduction in the longitudinal extension (19 mm vs. 26 mm; P < 0.01) were observed. The maximum aortic diameter evolved significantly between D0 and M1 in the unfavorable evolution group (49 mm vs. 44 mm, respectively; P = 0.038). Such a difference was not found in the favorable evolution group (37.4 vs. 37.1, respectively; P = 0.552). An overall significant reduction in the total aortic volume (166 cm³ vs. 219 cm³; P < 0.01), the circulating volume (124 cm³ vs. 145 cm³; P = 0,026), and the volume of the hematoma (42 cm³ vs. 39 cm³; P < 0.01) was observed. The circulating volume decreased significantly between D0 and M1 in the favorable evolution group (110 cm³ vs. 135 cm³; P = 0.05), whereas no difference was noted in the unfavorable group (142 cm³ vs, 157 cm³; P = 0.24).

CONCLUSIONS

The progression of the maximum aortic diameter and of the circulating volume after one month of follow-up could be predictive factors of the poor long-term evolution of type B intramural hematomas.

Thoracic Endovascular Aortic Repair for Type A Intramural Hematoma and Retrograde Thrombosed Type A Aortic Dissection: A Single-Center Experience

BACKGROUND

The aim of this study is to present our experience of thoracic endovascular aortic repair (TEVAR) for type A intramural hematoma (TAIMH) and retrograde thrombosed type A aortic dissection (rt-TAAD) with the entry tear in the descending aorta or the abdominal aorta and discuss the outcomes.

METHODS

We retrospectively reviewed total 6 patients who underwent TEVAR for TAIMH (n = 2) or rt-TAAD (n = 4) in our hospital between September 2017 and July 2019. The mean age of the patients (5 men and 1 woman) was 74 ± 13 years, and the mean follow-up duration was 13 ± 7 months.

RESULTS

TEVAR was successfully performed in the acute phase in all patients without relevant complications. After TEVAR, the shrinkage of enlarged thoracic aorta and complete resorptions of the false lumen of the entire thoracic aorta were achieved in 4 patients. In the remaining 2 patients, one had residual thrombosed false lumen of the ascending aorta due to a new development of PAU at the distal aortic arch and another needed additional endovascular intervention for ascending aorta hematoma progression. Late aorta-related adverse event was observed in one patient, who needed open aortic repair. There was no death during follow-up.

CONCLUSIONS

Tear-oriented endovascular aortic repair is a potential option in selected patients of TAIMH and rt-TAAD and has shown favorable immediate outcomes and aortic remodeling. However, the late aorta-related adverse event is not negligible, and their long-term outcome has not been fully clarified. More research is warranted.

Reinterventions in the modern era of thoracic endovascular aortic repair

OBJECTIVE

Using a national data set, we sought to describe the population of patients and the nature and timing of reinterventions after thoracic endovascular aortic repair (TEVAR) by aortic disease as well as their impact on survival.

METHODS

We evaluated the national data set for TEVAR in the Vascular Quality Initiative from 2010 to 2017. Student t-test and χ² analysis were used to compare continuous and categorical variables in the reintervention and no reintervention groups, respectively. Freedom from reintervention and survival analysis was performed using Kaplan-Meier methods.

RESULTS

A total of 7006 patients were evaluated: 51.2% thoracic aortic aneurysm, 33.5% type B dissection (TBD), 7.0% penetrating aortic ulcer, 6.7% trauma, and 1.6% intramural hematoma. Overall, 553 patients (7.9%) underwent at least one reintervention, with an in-hospital reintervention rate of 3.5%. Reinterventions were most commonly performed for TBD (11.5%), with reinterventions for other diseases occurring at lower rates: thoracic aortic aneurysm, 6.7%; intramural hematoma, 5.4%; penetrating aortic ulcer, 4.8%; and trauma, 1.8%. The most common cause of reintervention across all aortic diseases was type I endoleak. The most common long-term reinterventions were placement of endovascular stent graft (65%), other surgical treatments (15.9%), other endovascular treatment (13%), endovascular branch treatment (12.4%), surgical treatment with no device removal (11.0%), and surgical branch treatment (10.4%). Freedom from reintervention was decreased for TBD compared with other diseases (P < .001). There was no difference in survival comparing patients undergoing reinterventions and those without (P = .87). However, patients undergoing in-hospital reintervention trended toward increased mortality (P = .075).

CONCLUSIONS

Whereas reinterventions were not rare after TEVAR, there was no difference in mortality between patients undergoing reintervention and those without. Patients undergoing TEVAR for TBD demonstrated the highest reintervention rate. This study highlights the importance of long-term follow-up to address disease-specific patterns of reintervention.

A novel anatomic severity grading score for acute Type B aortic dissections and correlation to aortic reinterventions after thoracic endovascular aortic repair

Background

We introduce a novel preoperative anatomic severity grading system for acute type B aortic dissections and validate the system in a cohort of patients who underwent thoracic endovascular aortic repair.

Methods

We identified a cohort of patients who received thoracic endovascular aortic repair (TEVAR) for acute type B aortic dissection from 2008 to 2014. We developed an anatomic severity grading score (ASG) to measure attributes of aortic anatomy that we hypothesized may affect difficulty or durability of repair. Measurements were made using computed tomography angiography images and based on hypothesized severity, giving a potential score range of 0-38.

Results

We analyzed the computed tomography angiography images on a cohort of 30 patients with acute type B aortic dissection who underwent TEVAR. We created an area under the receiver operating characteristic curve (AUROC) using anatomic severity grading to predict aortic-related reinterventions. The AUROC was 0.72 (95% CI 0.39 to 1.1). Guided by the AUROC, we divided patients into two groups: a low-score group with anatomic severity grading scores <23 (n = 22), and a high-score group with scores ≥23 (n = 8). With this cutoff, anatomic severity grading exhibited 80% sensitivity and 84% specificity in predicting aortic-related reinterventions, with reinterventions in 50% of high-score patients and 4.5% of low-score patients (P = 0.011). The high score group also had significantly greater blood loss (200 vs 100 mL, P = 0.038), fluoroscopy time (36.0 vs 16.6 min; P = 0.022), and a trend for increased procedure time (164 vs 95 min; P = 0.083) than the low-risk group. Kaplan-Meier analysis revealed that the high-score group had a significantly decreased freedom from aortic-related reinterventions than the low-score group (38% vs 100% at 12-month followup; log rank P = 0.001).

Conclusions

A preoperative anatomic severity grading score for acute type B aortic dissections consists of analysis of the proximal landing zone, curvature and tortuosity of the aorta, dissection anatomy, aortic branch vessel anatomy, and supraceliac aorta anatomy. Anatomic severity grading scores ≤23 are an excellent predictor of aortic-related reinterventions.

Aortic intramural hemorrhage: A distinct disease entity with mystery

Aortic intramural hemorrhage (IMH) is one of the disease processes that comprise the spectrum of acute aortic syndrome (AAS) with clinical manifestations and a mortality rate similar to those of classic aortic dissection (AD). However, IMH should be considered as a distinct disease entity rather than a precursor to classic dissection because of differences in their pathology, etiology, natural history, and imaging findings. Multidetector computed tomography (CT) is recommended as the first-line diagnostic imaging modality for IMH, but transesophageal echocardiography (TEE) and magnetic resonance imaging (MRI) are also helpful. There is still debate over the appropriate treatment of IMH. Medical treatment of type B IMH appears effective and safe, while surgical treatment is recommended for type A IMH. Thoracic endovascular aortic repair (TEVAR) is a promising treatment for selected patients, and more clinical evidence needs to be assembled.

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.