Intramural haematoma of the thoracic aorta: who's to be alerted the cardiologist or the cardiac surgeon?

Mathematical modeling and numerical simulation of arterial dissection based on a novel surgeon's view

This paper presents a mathematical model for arterial dissection based on a novel hypothesis proposed by a surgeon, Axel Haverich, see Haverich (Circulation 135(3):205-207, 2017. https://doi.org/10.1161/circulationaha.116.025407 ). In an attempt and based on clinical observations, he explained how three different arterial diseases, namely atherosclerosis, aneurysm and dissection have the same root in malfunctioning Vasa Vasorums (VVs) which are micro capillaries responsible for artery wall nourishment. The authors already proposed a mathematical framework for the modeling of atherosclerosis which is the thickening of the artery walls due to an inflammatory response to VVs dysfunction. A multiphysics model based on a phase-field approach coupled with mechanical deformation was proposed for this purpose. The kinematics of mechanical deformation was described using finite strain theory. The entire model is three-dimensional and fully based on a macroscopic continuum description. The objective here is to extend that model by incorporating a damage mechanism in order to capture the tearing (rupture) in the artery wall as a result of micro-injuries in VV. Unlike the existing damage-based model of the dissection in the literature, here the damage is driven by the internal bleeding (hematoma) rather than purely mechanical external loading. The numerical implementation is carried out using finite element method (FEM).

Updates in aortic wall pathology

Several studies have investigated the pathogenesis of aortic wall abnormalities such as aortic dissection or aneurysm; however, the comprehensive pathological in situ event involved in the development of the disease is not understood well. The vasa vasorum form a network of capillaries or venules around the adventitia and outer media, which play an important role in the aortic wall structure and function. Impairment of their function may induce tissue hypoxia, impede the transfer of cellular nutrients, and cause aortic medial degeneration, which is considered the major predisposing factor to this aortic wall pathology. This review updates our understanding of the pathological changes in the aortic media and vasa vasorum of patients with aortic dissection and aortic aneurysm.

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.

Sequential ruptures of penetrating atherosclerotic ulcers of ascending aorta, aortic arch and descending thoracic aorta

Background

Penetrating ulcers of aorta, aortic dissections and intramural hematomas all come under acute aortic syndromes and have important similarities and differences.

Case report

We report a 67 year old man with rupture of a large penetrating ulcer of the distal ascending aorta with hemopericardium and left hemothorax. He underwent interposition graft replacement of ascending aorta and hemi-arch with a 30 mm Gelweave Vascutek graft but represented 6 months later with development of a penetrating ulcer which ruptured into a huge 14 cm pseudoaneurysm. This was repaired with a 28 mm Vascutek Gelseal graft replacement of arch and interposition graft reconstruction of innominate and left common carotid arteries. 6 weeks later, however, he ruptured his proximal descending aorta and underwent TEVAR satisfactorily. Unfortunately, 2 days later, he developed a pathological fracture of left proximal tibia with metastasis from a primary renal cell carcinoma. He died 3 weeks later from respiratory failure.

We shall briefly outline the similarities and differences in presentation and management of penetrating aortic ulcers, aortic dissections and intramural haematomas. We shall discuss, in greater detail, penetrating ulcers of thoracic aorta, their natural history, location, complications and management.

Conclusion

This case report is unique on account of initial successful surgical redressal following rupture of penetrating ulcer of distal ascending aorta into left pleural and pericardial cavities, normally associated with instant death. The haemodynamic effects of the rupture were staggered due to initial contained rupture into a smaller pseudoaneurysm, followed by a further rupture into a false aneurysmal sac followed eventually by generalised rupture into the pleural and pericardial cavities - a unique way of aortic rupture. Further development of another penetrating ulcer and a small pseudoaneurysm in the distal arch 6 months later which further ruptured into a larger 14 cm false aneurysmal sac, which again did not result in exsanguination, is again extraordinarily rare. Thereafter he underwent emergency thoracic endovascular aortic repair (TEVAR) for a further rupture of descending thoracic aorta. All three ruptures were managed successfully and would usually be associated with near-certain death, only for the patient to succumb eventually to the complications of metastatic renal cell carcinoma.

Successful Conservative Treatment of a Type A Aortic Intramural Hematoma

Type A intramural hematoma (IMH) constitutes a variant of acute aortic syndrome. Western guidelines support an aggressive surgical approach, whereas Asian centers propose initial conservative treatment. Further expanding on this notion, we present a case of conservative subacute type A IMH management, resulting in radical hematoma resorption within 4 weeks. (Level of Difficulty: Beginner.).

Broken-crescent sign at CT indicates impending aortic rupture in patients with acute aortic intramural hematoma

Background

This retrospective study evaluated the computed tomography (CT) features and clinical implications of a novel broken-crescent sign in patients with acute aortic intramural hematoma (IMH).

Methods

Out of 104 patients with aortic IMH encountered in our institution between 2003 and 2018, nine patients exhibited a positive broken-crescent sign, which was defined as a focal defect within the hyper-attenuating crescentic IMH on unenhanced CT, corresponding to a smooth out-bulging of the aortic lumen on enhanced study. The clinical findings, CT features, and outcomes of these nine patients were analyzed.

Results

Of five males and four females (age range 48–84 years, mean 69.7 years), six had type A and three had type B IMH. Five patients who had medical treatment and stable status for 1 to 3 days suffered sudden death, two of whom showed ascending aortic rupture with hemopericardium in one and adventitial tear with outward spillage of IMH in another at follow-up CT. The other four patients had early surgical or endovascular management survived; two demonstrated ascending aorta ecchymosis with adventitial tear and intact intima at surgery. Our results support the supposition that aortic IMH complicated with adventitial tear and partial outward seepage of IMH may generate a broken-crescent sign in CT. Despite initially stable clinical status, the residual intact inner aortic wall carries a high risk of sudden aortic rupture.

Conclusions

In patients with acute aortic IMH, identification of a broken-crescent sign in CT is highly suggestive of impending aortic rupture, and early aggressive treatment is mandatory.

Five-year outcomes after thoracic endovascular aortic repair of symptomatic type B penetrating aortic ulcer with intramural hematoma in Chinese patients

Background

The aim of this study is to evaluate the five-year outcomes after thoracic endovascular aortic repair (TEVAR) of symptomatic Stanford type B penetrating aortic ulcer (PAU) associated with intramural hematoma (IMH) in Chinese patients.

Methods

From January 2009 to April 2013, 118 patients with typical severe acute chest pain were diagnosed with Stanford type B acute aortic syndrome (AAS) in our department and received TEVAR. Within the group, 28 patients were diagnosed with PAU associated with IMH by computed tomography angiography (CTA) and subsequently evaluated with repeated CTA. All 28 patients' clinical and follow-up data were collected for 60 months.

Results

PAU associated with IMH continued to progress for approximately 14 days and sometimes a few days more. Twenty-eight patients underwent TEVAR under general anesthesia via femoral artery access. Technical success was achieved in 100% of cases. Two stent grafts were used in 1 patient to achieve effective coverage of the PAUs and IMH. The follow-up rate was 92.8%. Two patients were lost to follow-up in the 4^th and 16^th months due to relocation. All patients remained free of aortic symptoms during follow-up. Two heavy smoker patients in whom the ostium of the left subclavian artery (LSCA) was completely covered by the graft had transient dizziness upon resumption of smoking during follow-up. There were 2 early type II endoleaks but no aortic expansion. No patient needed reintervention. One patient died in a car accident at 42 months. Four patients safely underwent noncardiovascular surgery. The 1-, 2-, and 5-year overall survival rates were 100%, 100%, and 96.1%, respectively.

Conclusions

The short- and mid-term results of TEVAR treatment for symptomatic Stanford type B PAU associated with IMH in Chinese patients were encouraging. Long-term follow-up is anticipated.

Multislice spiral CT angiography for evaluation of acute aortic syndrome

OBJECTIVE

To discuss the diagnostic value of multislice CT angiography (MSCTA) in acute aortic syndrome (AAS).

MATERIALS AND METHODS

The clinical and imaging data of 36 cases diagnosed as AAS by MSCTA were collected. The manifestations of the MSCTA images were reviewed retrospectively, and the average x-ray dose was calculated.

RESULTS

Among 36 AAS cases, 16 cases had aortic dissection (AD), 8 cases had penetrating atherosclerotic ulcer (PAU), 7 cases had intramural hematoma (IMH), and 5 cases had unstable thoracic aneurysm (UTA). Of 16 cases with AD, type A and type B accounted for 43.7% (7/16) and 56.3% (9/16), respectively. Of 7 cases with IMH, type A and type B accounted for 42.9% (3/7) and 57.1% (4/7), respectively.

CONCLUSION

In spite of the x-ray radiation, MSCTA proves to be a rapid and noninvasive imaging technique for the diagnosis of AAS.

[Acute aortic diseases. Diagnostic imaging and therapy]

Diagnostic imaging is crucial in the work-up of acute aortic diseases. Current imaging algorithms enable radiologists differentiating the various entities with subsequent clinically relevant treatment options. Within this educational overview we focus on non-traumatic acute aortic disease. Recent developments of cross sectional imaging are summarized. As for acute aortic disease, we discuss dissections, intramural hematoma, penetrating aortic ulcer, and aortitis. Current treatment options are presented.

Treatment patterns and their outcomes of acute aortic intramural hematoma in real world: multicenter registry for aortic intramural hematoma

Background

Intramural hematoma of the aorta (IMH), a variant of classic aortic dissection, shows very dynamic process in the early phase. The aim of this study is to evaluate clinical outcomes of patients with acute aortic IMH from real world registry data.

Methods

We analyzed 165 consecutive patients with acute IMH from five medical centers in Korea. All patients were divided into two groups; type A (n = 61, 37.0%) and type B (n = 104, 63.0%) according to the Stanford classification. Clinical outcomes and morphological evolution by CT were analyzed for 2 years.

Results

Most of the patients (77.0% of type A and 99.0% of type B, P < 0.001) were treated medically during their initial hospitalization. There were no significant differences in in-hospital mortality (4.9% vs. 2.9%, P = 0.671) and 2-year mortality (13.1% vs. 11.5%, P = 0.765) between two groups. During the 2-year follow up period, progression to aortic dissection (18.0% vs. 6.7%, P = 0.037) and surgical treatment (29.5% vs. 2.9%, P < 0.001) were higher in type A. For the type A patients, there were no significant difference in in-hospital mortality (7.1% of surgery vs. 4.3% of medical, P = 0.428) and 2-year mortality (7.1% of surgery vs. 14.9% of medical, P = 0.450) in terms of initial treatment strategy.

Conclusion

For real world practice in Korea, most of IMH patients were treated medically at presentation and showed favorable outcomes. Thus, even in type A acute IMH, early medical treatment with alternative surgical conversion for selected, complicated cases would be a favorable treatment option.

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.

Surgical treatment or conservative therapy for stanford type a acute aortic dissection with a thrombosed false lumen

OBJECTIVES

Optimum treatment for acute aortic dissection (AAD) with a thrombosed false lumen (thrombosed AAD) remains controversial. We evaluated the outcome of thrombosed AAD according to treatment strategy.

MATERIALS AND METHODS

We examined 280 patients with AAD, of which 30 had thrombosed AAD. We compared computed tomography findings, cardiac performance, and clinical course in 28 of these patients. Patients were divided into three groups for the comparison: Group E (emergency surgery), Group C (conservative therapy), and Group S (conservative therapy switched to emergency surgery).

RESULTS

In Group E (n = 13), one patient died and 12 survived. In Group C (n = 10), all patients were discharged, of which two died of cancer and two of the remaining eight survivors underwent subsequent elective surgery. In Group S (n = 5), one patient died and four survived following surgery.

CONCLUSIONS

It was hard to predict re-dissection or rupture following conservative treatment for thrombosed AAD. Basically, we should perform emergency surgery following the diagnosis of thrombosed AAD, particularly in complicated cases such as those with pericardial effusion, tamponade, and large aorta. Conservative therapy has a very limited application in patients with the initial stages of thrombosed AAD.

Intramural collection caused by contrast extravasation into the ascending aortic wall

Cardiac catheterization is a procedure routinely performed worldwide, with an estimated amount of 61,000 coronary angioplasties performed in the UK annually. Associated mortality--in the region of 0.1-0.2%--is minimal and complication rate approximately 1.5%. The most serious complications described are embolic stroke, cardiac chamber perforation, aortic dissection, coronary occlusions or dissection, and major peripheral vascular complications, including retroperitoneal haematoma and life-threatening haemorrhage. We report the case of a 75-year old patient who had inadvertent contrast agent injection into the aortic wall, leading to a localized contrast collection within the tunica media. This complication has been described before but only in association with coronary artery dissection. It is important to diagnose and manage such a situation, as most iodinated intravascular contrast agents exert a high osmotic load and thereby lead to tissue oedema and necrosis on extravasation. We describe the management of the case and discuss relevant therapeutic strategies.

Endovascular management of acute aortic syndromes

The term "acute aortic syndrome" (AAS) refers to a spectrum of life-threatening thoracic aortic pathologies including intramural hematoma, penetrating atherosclerotic ulcer, and aortic dissection. Clinically, patients often present with characteristic aortic pain. AAS often leads to aortic rupture. Therefore, recognition of this condition, its prompt diagnosis, and timely treatment is crucial to obtain clinical success and improved overall survival. The management of AAS, however, remains a therapeutic challenge. Endovascular strategies have gained wide acceptance and now represent a minimally invasive alternative to traditional open surgery. Several studies have shown endovascular repair of varying thoracic aortic pathologies to be technically feasible with fewer complications than open surgery. In this review, the authors discuss AAS pathology and its management, with particular attention to the current role of endovascular aortic repair and its treatment.

Utility of measuring C-reactive protein for prediction of in-hospital events in patients with acute aortic dissection

Controlling blood pressure is essential for prevention of events after acute aortic dissection (AAD). However, in some instances a cardiac event occurs despite controlled blood pressure, and its prediction is difficult. We continuously monitored C-reactive protein (CRP) in patients receiving medical treatment for AAD and retrospectively examined the utility of CRP measurement for prediction of in-hospital events. Five hundred and eight patients were diagnosed as having AAD between 1993 and 2009, 240 of whom underwent antihypertensive medical therapy. These subjects were 156 males and 84 females, average age 67.4 years, with 68 cases of Stanford type A and 172 cases of Stanford type B. C-reactive protein was measured in all patients daily until a peak; subsequently, CRP was measured 2-3 times per week following the peak until discharge. In the event-free group CRP demonstrated a peak on the 4th day after the onset (average 13.7 mg/dl), then gradually decreased to an average of 4.6 mg/dl 4 weeks later, displaying a "gradual decay" pattern. Despite controlled systolic arterial pressure of approximately 120 mmHg, 7 of 68 Stanford A cases (10.3 %) and 8 of 172 Stanford B cases (4.7 %) developed cardiovascular events. The group characterized by events exhibited a CRP pattern distinct from that of the event-free group, i.e., prolonged elevation and/or re-elevation. We demonstrated that the CRP pattern could provide information regarding prediction of cardiovascular events. Prolonged elevation or re-elevation of CRP may indicate the necessity of (1) application of computed tomography or magnetic resonance imaging, (2) more rigorous blood pressure management, or (3) early surgical intervention.