Prediction of progression or regression of type A aortic intramural hematoma by computed tomography

CT Analysis of the Growth Rate of Aortic Diameter Affected by Acute Type B Intramural Hematoma

OBJECTIVE

The purpose of this study was to evaluate the growth rate of aortic diameter affected by acute type B intramural hematoma and the factors that influence its enlargement.

MATERIALS AND METHODS

Fifty-four patients were entered into this study, and regular follow-up CT studies (mean +/- SD, 46.9 +/- 27.2 months; range, 5-136 months) were performed. The affected aortas and iliac arteries were divided into five segments. A total of 127 segments were evaluated (aortic arch, n = 47; descending thoracic aorta, n = 51; suprarenal abdominal aorta, n = 24; infrarenal abdominal aorta, n = 3; and iliac artery, n = 2). The growth rate of each segment was obtained on CT. The factors influencing increase in the diameter and growth rate--age, sex, diabetes mellitus, atherosclerotic disease, history of smoking 20 years, chronic renal failure, blood pressure, initial diameter of the lumen, the presence of blood flow in the false lumen--were evaluated by univariate analysis and a multivariate logistic regression model.

RESULTS

Twenty (37.0%) of 54 patients had one or more segments that increased in size during the follow-up period. Of a total of 127 segments, 35 (27.6%) increased in size, and for all, the mean growth rate was -0.5 +/- 2.9 mm/year. This negative growth rate represents shrinkage. The mean growth rates within the first year and after 1 year from onset were -2.2 +/- 5.7 and 0.4 +/- 3.2 mm/year, respectively, and a significant difference was observed between them (p < 0.0001). An initial diameter of 40 mm or greater and the presence of blood flow in the false lumen were significant risk factors for an increase in the diameter, as confirmed by univariate and multivariate analyses.

CONCLUSION

In patients with type B intramural hematoma, the affected aortas did not show a high incidence of enlargement during the follow-up period, but the affected aortas tended to increase in size after 1 year from onset. An initial diameter of 40 mm or greater and the presence of blood flow in the false lumen were important risk factors for enlargement during the follow-up period.

Aortic intramural hematoma: a case report of spontaneous resolution

Aortic intramural hematoma is an acute aortic syndrome caused by hemorrhage within the aortic wall and characterized by the absence of an intimal tear and false lumen, which are the main features of classic aortic dissection. Although surgical intervention represents the standard management of type A aortic intramural hematoma, the possibility of treating some patients with medical therapy associated with serial imaging evaluations at follow-up has recently been demonstrated.

Nontraumatic Thoracic Emergencies

Acute chest pain is one of the most common complaints of patients who present to an emergency department, and accounts for up to 5% of all visits. It also is one of the most complex issues in an emergency setting because, although clinical signs and symptoms often are nonspecific, rapid diagnosis and therapy are of great importance. The chest radiograph remains an important component of the evaluation of chest pain, and usually is the first examination to be obtained. Nevertheless, cross-sectional imaging has added greatly to the ability to characterize the wide constellation of clinical findings into a distinct etiology. This article reviews how the various entities that can present as nontraumatic chest pain can manifest radiographically.

Pathologic Characteristics and Surgical Indications of Superacute Type A Intramural Hematoma

BACKGROUND

The treatment policy for acute intramural hematoma involving the ascending aorta remains controversial.

METHODS

This study compared the pathologic characteristics of intramural hematoma with those of acute aortic dissection with a false lumen. The study group comprised 69 patients with intramural hematoma and 156 with acute aortic dissection who underwent emergency operation between 1995 and 2003.

RESULTS

Patients were significantly older in the intramural hematoma group than in the dissection group (67.7 +/- 7.2 years compared with 59.8 +/- 11.6 years; p < 0.0001). Pericardial hemorrhage was present in a higher proportion of patients in the intramural hematoma group than in the dissection group (66.7% compared with 50.6%; p = 0.0257). Three patients (4.3%) died in the intramural hematoma group, whereas 26 patients (16.7%) died in the dissection group (p = 0.011). Histopathologic examination showed no difference in the severity of medial changes, but the site of dissection differed. The thickness of the residual media of the adventitia side was 0.21 +/- 0.12 mm in the intramural hematoma group compared with 0.32 +/- 0.22 mm in the acute aortic dissection group. Dissection was significantly nearer the adventitia in the intramural hematoma group (p = 0.0016).

CONCLUSIONS

Dissection is nearer the adventitia in intramural hematoma than in dissection, leading to a greater probability of rupture. These results suggest that operation as soon as possible after the onset of intramural hematoma will contribute to improved survival.

Penetrating atherosclerotic ulcer of the descending thoracic aorta and arch

OBJECTIVE

The clinical behavior of penetrating atherosclerotic ulcers of the aorta is controversial. We reviewed our experience with this entity over a 25-year interval.

METHODS

Cases were identified using the Department of Radiology database searching for the diagnoses of aortic dissection, intramural hematoma, or penetrating ulcer between 1977 and 2002. Available imaging studies were reviewed by a vascular radiologist to confirm the diagnosis of penetrating ulcer and perform serial measurements.

RESULTS

One hundred five patients with penetrating atherosclerotic ulcers of the descending thoracic aorta or arch with (n = 85) or without (n = 20) associated intramural hematoma were confirmed. Two patients with ulcers in the ascending aorta were excluded. There were 73 men and 32 women with a mean age of 72 +/- 9 years. Comorbidities included hypertension in 97 (92%), tobacco use in 81 (77%), and coronary artery disease in 48 (46%). Of nonoperated patients with follow-up studies, the mean thickness of the intramural hematoma decreased at 1 month in 89% and completely resolved at 1 year in 85%. There were 3 deaths (4%) within 30 days among 76 patients treated medically and 6 deaths (21%) among 29 patients treated surgically (P <.05). Failure of medical therapy defined as surgery or death was predicted by rupture at presentation (odds ratio = 20.6) and era of treatment (before 1990, odds ratio 9.9) but not aortic diameter, ulcer size, or extent of hematoma.

CONCLUSION

Although careful follow-up is necessary, many penetrating atherosclerotic ulcers of the thoracic aorta can be managed nonoperatively in the acute setting.

Clinical features and long-term outcome of type A and type B intramural hematoma of the aorta

OBJECTIVE

Most previous reports on intramural hematoma of the aorta have focused on the initial episode. The purpose of this study was to clarify the long-term outcome of intramural hematoma of the aorta.

METHODS

Ninety-four cases of intramural hematoma of the aorta (41 type A and 53 type B) were reviewed. There were 69 male and 25 female patients, and their mean age was 66.7 +/- 8.7 years (range, 46-88 years).

RESULTS

Eleven (27%) of the patients with type A hematoma and 1 (2%) of the patients with type B hematoma underwent early surgical intervention. Others were treated medically, and the overall hospital mortality was 7% for patients with type versus 2% for patients with type B intramural hematomas of the aorta (P =.315). Twenty-three patients, 9 (22%) with type A and 14 (26%) with type B intramural hematomas of the aorta, underwent late surgical intervention during the follow-up period, and there were no hospital deaths. A total of 23 patients died during the follow-up period, including 6 of intramural hematoma of the aorta-related deaths (3 in the type A group and 3 in the type B group). The estimated freedom from intramural hematoma of the aorta-related events at 1 and 5 years was 70% +/- 8% and 54% +/- 11% for the type A group versus 73% +/- 6% and 58% +/- 8% for the type B group, respectively (P =.972). After excluding the nonintramural hematoma of the aorta-related deaths, the survival rates at 5 and 10 years were 80% +/- 9% and 80% +/- 9% for the type A group and 91% +/- 8% and 81% +/- 11% for the type B group (P =.211).

CONCLUSIONS

Intramural hematoma of the aorta-related events occur equally in both types of intramural hematoma of the aorta. We recommend close follow-up for at least 5 years because most intramural hematoma of the aorta-related events occur during this period.

CT in nontraumatic acute thoracic aortic disease: typical and atypical features and complications

Thoracic aortic dissection is the most frequent cause of aortic emergency, and unless it is rapidly diagnosed and treated, the result is death. Helical computed tomography (CT) permits the diagnosis of acute aortic dissection with a sensitivity and specificity of nearly 100%. This imaging modality also enables differentiation between proximal aortic dissection (type A in the Stanford classification) and distal aortic dissection (Stanford type B), which are treated differently and have different prognoses. In 70% of patients in whom nontraumatic acute thoracic aortic dissection is diagnosed after evaluation with helical CT, scans show the typical signs of aortic dissection, with rupture and displacement of the intima. CT also can depict other pathologic entities with similar clinical manifestations, such as intramural hematoma and penetrating atherosclerotic ulcer. Awareness of the different radiologic appearances of these disease entities is essential for differential diagnosis. More than one-third of patients with aortic dissection show signs and symptoms indicative of systemic involvement. Because branch-vessel involvement may increase morbidity and mortality, in this group of patients it is important to evaluate the entire aorta so as to determine the distal extent of the dissection and detect any systemic involvement.

Long-term prognosis of patients with type B aortic intramural hematoma

BACKGROUND

The long-term clinical course of patients with type B aortic intramural hematoma (IMH) and predictors for progression remains unknown. The difference of aortic pathology may have a different impact on clinical course compared with classic aortic dissection (AD). The purpose of this study was to investigate long-term clinical course and predictors of progression in patients with type B IMH.

METHODS AND RESULTS

Clinical data were compared retrospectively between 53 patients with acute type B IMH (IMH group) and 57 patients with acute type B AD (AD group). All patients were treated initially with medical therapy. Two patients in IMH group and 14 patients in AD group underwent surgical repair because of aortic enlargement. The in-hospital mortality rate in IMH group was significantly lower than that in AD group (0% and 14%, P=0.006). Mean follow-up periods were 53+/-43 months, which revealed 3 and 5 late deaths, respectively. Eleven patients with IMH showed progression (development of aortic dissection or aortic enlargement) in follow-up imaging study. The actuarial survival rates in IMH group were 100%, 97%, and 97% at 1, 2, and 5 years, which were significantly higher than those in AD group (83%, 79%, and 79%) (P=0.009). Multivariate analysis identified age >70 years and new appearance of an ulcerlike projection as the strongest predictors of progression in patients with IMH.

CONCLUSIONS

Patients with type B IMH have better long-term prognosis than patients with AD. Older age and appearance of an ulcerlike projection are predictive for progression in patients with type B IMH.

Usefulness of the initial noninvasive imaging study to predict the adverse outcomes in the medical treatment of acute type A aortic intramural hematoma

BACKGROUND

There have been contradictory reports about the outcomes of medically treated patients with type A aortic intramural hematoma (AIH), and it is not certain if the initial noninvasive imaging studies can provide any useful predictors for the adverse outcomes.

METHODS AND RESULTS

Imaging studies and clinical outcomes of 25 consecutive patients with type A AIH who initially received medical treatment were analyzed retrospectively. Adverse outcomes (death, surgery, and development of dissection) occurred in 9 patients (group A), whereas the other 16 patients showed an uneventful course (group B). The hematoma thickness (14+/-4 versus 8+/-4 mm, P<0.005) and hematoma area (988+/-316 versus 555+/-352 mm2, P<0.01) in the imaging study performed <or=48 hours after onset of initial symptoms were significantly larger in group A; maximal aortic diameter (53+/-6 versus 48+/-8 mm, P=0.10) and aortic cross-sectional area (2247+/-501 versus 1809+/-626 mm2, P=0.09) were also somewhat larger in group A. The hematoma thickness was the only independent predictor for the adverse outcomes by stepwise multiple logistic regression analysis (odds ratio 1.41, 95% confidence interval 1.07 to 1.86, P<0.05). Hematoma thickness >or=11 mm predicted the adverse outcomes with sensitivity 89% and specificity 69%. No one with hemodynamically stable initial condition and the hematoma thickness <11 mm experienced the adverse outcomes.

CONCLUSIONS

Noninvasive imaging study provides important prognostic information in the medical treatment of acute type A AIH, and initial hematoma thickness seems to be the best index for predicting adverse clinical outcome.

Acute aortic syndrome: a case presentation and review of the literature

Aortic disease can present as an acute chest pain syndrome. Although aortic dissection is the most common etiology, other processes such as intramural hematoma (IMH) and penetrating atherosclerotic ulcers are being increasingly recognized. They can all be accurately identified by computed tomography (CT) imaging or transesophageal echocardiography. The overlap between these processes regarding definition and mechanism is controversial. Treatment for all three conditions has thus far been dictated by location, wherein ascending or arch involvement (Stanford type A) necessitates surgery and descending disease (type B) is treated medically. Small studies suggest that subgroups of type A IMH may be treated medically with good outcomes.

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

PURPOSE

To investigate the natural history and predictors of progression of a newly developed ulcerlike projection in patients with an aortic intramural hematoma.

MATERIALS AND METHODS

Serial computed tomographic (CT) findings in 52 patients with intramural hematoma were reviewed. Sixteen patients had Stanford type A intramural hematoma, and 36 had Stanford type B. Diagnosis of intramural hematoma was established with CT. Regular follow-up studies were performed every week during the 1st month and two or three times a year after the 2nd month. The presence or absence of an ulcerlike projection, diameter and progression of the projection, and aortic diameter were evaluated. Relationships among ulcerlike projections, clinical data, and CT findings were analyzed.

RESULTS

In 17 (33%) of the 52 patients, 17 ulcerlike projections were newly identified during the follow-up period. Patients with type A intramural hematoma had a significantly higher frequency of new development of ulcerlike projection than that of patients with type B intramural hematoma (P =.002). In 17 patients with new development of ulcerlike projection, 12 (70%) of 17 projections progressed to complications such as enlargement (n = 10) or progression to overt aortic dissection (n = 2). One of 10 enlarged projections progressed to rupture. A significant predictor of progression of ulcerlike projection was based on location from the ascending aorta to the aortic arch with the use of univariate (P =.009) and multivariate Cox (P =.018) regression analyses.

CONCLUSION

The location of ulcerlike projections is the principal predictor of progression, and careful follow-up study is needed for patients with an ulcerlike projection located from the ascending aorta to the aortic arch.