The differences and similarities between intramural hematoma of the descending aorta and acute type B dissection

Introduction Aortic intramural hematoma type B (IMHB) is a variant of acute aortic syndrome, which presents with symptoms similar to classic type B aortic dissection (ABAD). However, the natural history of IMHB is not well understood. The purpose of this study was to better characterize IMHB, comparing its clinical characteristics, treatment, and in-hospital and long-term outcomes to those with classic ABAD. Methods A total of 107 IMHB and 790 ABAD patients enrolled in the International Registry of Acute Aortic Dissection (IRAD) between January 1996 and June 2012 were analyzed. Accordingly, differences in presentation, diagnostics, therapeutic management, and outcomes were assessed. Results As compared with the ABAD, IMHB presented predominantly in males (62% vs 33%; P <.001) at older age (69 \ub1 12 vs 63 \ub1 14; P <.001). IMHB patients more often had chest pain (80% vs 69%; P =.020) and periaortic hematoma (22% vs 13%; P =.020) and were more often treated medically (88% vs 62%; P <.001), with surgical/endovascular interventions being reserved for more complicated patients. Overall in-hospital mortality was 10% (IMHB, 7% vs ABAD, 11%; P = NS). Six out of seven IMHB deaths occurred during medical treatment, two due to aortic rupture. During follow-up in IMHB, patient mortality was 7%, and no adverse events, including progression to an aortic dissection or aortic rupture, were observed. Imaging showed significantly more aortic enlargement at the level of the descending aorta in ABAD patients (39% vs 61%; P =.034). Conclusions Most IMHB patients can be treated medically, and aortic enlargement is less common during follow-up, which may suggest that IMHB may have a slightly more benign course compared with classic ABAD in the acute setting

Predictors of false lumen thrombosis in type B aortic dissection treated with TEVAR

BACKGROUND: Thoracic endovascular aortic repair (TEVAR) offers a less invasive treatment option in type B aortic dissection (TBAD) patients and its value has been demonstrated in acute and chronic dissection patients. Total false lumen thrombosis (FLT) is associated with better long-term outcome in these patients, however, this is not obtained in all patients. The purpose of this study was to investigate predictors of FLT. METHODS: We retrospectively investigated patients who underwent TEVAR for a type B dissection in a large referral center between 2005 and 2012. All patients with a CT angiogram (CTA) obtained preoperatively, postoperatively and after one year of follow-up were selected for analysis. Volume measurements and several morphologic characteristics were analyzed for all scans using Aquarius iNtuition software (TeraRecon, San Mateo, Calif, USA). Multivariate logistic regression analyses were used to study the influence of these characteristics on FLT. RESULTS: Of 132 patients that received TEVAR for an aortic dissection, 43 patients (mean age, 60.3\ub114.2; 30 male) met our inclusion criteria, of whom 16 (37%) developed full FLT after 1 yr of follow-up. Multivariate logistic regression showed that side branch involvement [odds ratio (OR), 0.03; 95% confidence interval (CI), 0.00-0.92; P=0.045] and a total patent false lumen (FL) at presentation (OR, 0.01; 95% CI, 0.00-0.58; P=0.027) were associated with decreased complete FLT. Volumetric data showed significantly more reduction of the thoracic false lumen in FLT patients compared with non-FLT (-52.3% vs. -32.4%; P=0.043) and also a tendency of less volume increase in the abdominal segment (-5.0\ub137.5 vs. 21.8\ub144.3; P=0.052). CONCLUSIONS: Patients admitted with type B dissection and branch vessel involvement or a patent entry tear after TEVAR are less likely to develop FLT and aortic remodeling during follow-up. These findings suggest that these patients may require a more extensive procedure and more intensive follow-up to prevent long-term complications

Influence of clinical presentation on the outcome of acute B aortic dissection : evidences from IRAD

In-hospital outcome of acute type B dissection (ABAD) is strongly related to preoperative aortic conditions. In order to clarify the influence of the clinical presentation on the outcome, we analyzed the patients of the International Registry of Acute Aortic Dissection (IRAD). All patients affected by complicated ABAD, enrolled in the IRAD from 1996-2004, were included. Complications were defined as the presence of shock, periaortic hematoma, spinal cord ischemia, preoperative mesenteric ischemia/infarction, acute renal failure, limb ischemia, recurrent pain, refractory pain or refractory hypertension (group I). All other patients were categorized as uncomplicated (group II). A comprehensive analysis was performed of all clinical variables in relation to in-hospital outcome

Acute type B aortic dissection in the absence of aortic dilatation

Background: Increasing aortic diameter is thought to be an important risk factor for acute type B aortic dissection (ABAD). However, some patients develop ABAD in the absence of aortic dilatation. In this report, we sought to characterize ABAD patients who presented with a descending thoracic aortic diameter <3.5 cm. Methods: We categorized 613 ABAD patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2009 according to the aortic diameter <3.5 cm (group 1) and <3.5 cm (group 2). Demographics, clinical presentation, management, and outcomes of the two groups were compared. Results: Overall, 21.2% (n = 130) had an aortic diameter <3.5 cm. Patients in group 1 were younger (60.5 vs 64.0 years; P =.015) and more frequently female (50.8% vs 28.6%; P <.001). They presented more often with diabetes (10.9% vs 5.9%; P =.050), history of catheterization (17.0% vs 6.7%; P =.001), and coronary artery bypass grafting (9.7% vs 3.4%; P =.004). Marfan syndrome was equally distributed in the two groups. The overall in-hospital mortality did not differ between groups 1 and 2 (7.6% vs 10.1%; P =.39). Conclusions: About one-fifth of patients with ABAD do not present with any aortic dilatation. These patients are more frequently females and younger, when compared with patients with aortic dilatation. This report is an initial investigation to clinically characterize this cohort, and further research is needed to identify risk factors for aortic dissection in the absence of aortic dilatation

Impact of Retrograde Arch Extension in Acute Type B Aortic Dissection on Management and Outcomes

Background. Optimal management of acute type B aortic dissection with retrograde arch extension is controversial. The effect of retrograde arch extension on operative and long-term mortality has not been studied and is not incorporated into clinical treatment pathways. Methods. The International Registry of Acute Aortic Dissection was queried for all patients presenting with acute type B dissection and an identifiable primary intimal tear. Outcomes were stratified according to management for patients with and without retrograde arch extension. Kaplan-Meier survival curves were constructed. Results. Between 1996 and 2014, 404 patients (mean age, 63.3 +/- 13.9 years) were identified. Retrograde arch extension existed in 67 patients (16.5%). No difference in complicated presentation was noted (36.8% vs 31.7%, p = 0.46), as defined by limb or organ malperfusion, coma, rupture, and shock. Patients with or without retrograde arch extension received similar treatment, with medical management in 53.7% vs 56.5% (p = 0.68), endovascular treatment in 32.8% vs 31.1% (p = 0.78), open operation in 11.9% vs 9.5% (p = 0.54), or hybrid approach in 1.5% vs 3.0% (p = 0.70), respectively. The in-hospital mortality rate was similar for patients with (10.7%) and without (10.4%) retrograde arch extension (p = 0.96), and 5-year survival was also similar at 78.3% and 77.8%, respectively (p = 0.27). Conclusions. The incidence of retrograde arch dissection involves approximately 16% of patients with acute type B dissection. In the International Registry of Acute Aortic Dissection, this entity seems not to affect management strategy or early and late death

Role and results of surgery in acute type B aortic dissection : insights from the International Registry of Acute Aortic Dissection (IRAD)

BACKGROUND: The clinical profiles and outcomes of patients treated surgically for acute type B aortic dissection (ABAD) are often reported for those in small series or for those cared for at a single institution over a long time period, during which a continuous evolution in techniques has occurred. Accordingly, we sought to evaluate the clinical features and surgical results of patients enrolled in the International Registry of Acute Aortic Dissection by identifying primary factors that influenced surgical outcome and estimating average surgical mortality for ABAD in the current era. METHODS AND RESULTS: A comprehensive analysis of 290 clinical variables and their relation to surgical outcomes for 82 patients who required surgery for ABAD (from a population of 1256 patients; mean+/-SD age, 60.6+/-15.0 years; 82.9% male) and who were enrolled in the International Registry of Acute Aortic Dissection was performed. The overall in-hospital mortality was 29.3%. Factors associated with increased surgical mortality based on univariate analysis were preoperative coma or altered consciousness, partial thrombosis of the false lumen, evidence of periaortic hematoma on diagnostic imaging, descending aortic diameter &rt;6 cm, right ventricle dysfunction at surgery, and shorter time from the onset of symptoms to surgery. Factors associated with favorable outcomes included radiating pain, normotension at surgery (systolic blood pressure 100 to 149 mm Hg), and reduced hypothermic circulatory arrest time. The 2 independent predictors of surgical mortality were age &rt;70 years (odds ratio, 4.32; 95% confidence interval, 1.30 to 14.34) and preoperative shock/hypotension (odds ratio, 6.05; 95% confidence interval, 1.12 to 32.49). CONCLUSIONS: The present study provides insights into current-day clinical profiles and surgical outcomes of ABAD. Knowledge about different preoperative clinical conditions may help surgeons in making treatment decisions among these high-risk patients