Chronic Type B Aortic Dissection Research Articles

Propensity Adjusted Analysis of Open and Endovascular Thoracic Aortic Repair for Chronic Type B Dissection: A Twenty-Year Evaluation

Optimal treatment of chronic type B aortic dissection (CBAD), whether open (open descending aortic repair, OAR) or endovascular (thoracic endovascular aortic repair, TEVAR), is controversial, suggesting a comparative analysis is warranted. One hundred twenty-two of 1,049 patients (1993 to 2013) undergoing descending aortic repair required intervention for CBAD 29.2 ± 34.9 months after the initial acute event and formed the study cohort (mean age 59.7 years). Those with degenerated residual type A dissection were excluded (n= 65). Eighty-eight had extent IIIB CBAD; 11 had intramural hematoma. Indications for surgery included aneurysmal degeneration (n= 105), rupture (n= 8), acute or chronic dissection (n= 8), and extension of dissection (n= 1). Open strategy included descending (n= 71) and thoracoabdominal repair (n=19), with hypothermic circulatory arrest used in 70 patients. The TEVAR was performed with (n= 2) or without (n= 30) visceral debranching. A treatment strategy propensity score incorporating time since initial acute event, CBAD extent, year of intervention, age, and selected comorbidities was constructed for multivariable analysis. Early outcome included the following: 30-day mortality 4% (n= 5); stroke 2% (n= 2); permanent paraplegia 3% (n= 4); renal failure requiring dialysis 7% (n= 8, 5 temporary and 3 permanent); and tracheostomy 3% (n= 4). Visceral aorta intervention (odds ratio [OR] 3.5, p= 0.026) and maximum aortic diameter (OR 1.1, p= 0.001) but not treatment type (p= 0.64) independently predicted an early composite outcome comprised of these variables. Ten-year survival was 56.2%. Baseline creatinine (hazard ratio [HR] 1.7, p < 0.001) and peripheral vascular disease (HR 2.5, p= 0.021), but not treatment type (p= 0.225) predicted late mortality. Ten-year freedom from aortic rupture or need for reintervention was 78.3%. Treatment efficacy was improved after OAR (3-year freedom 96.7% vs TEVAR 87.5%, p= 0.026), and this was confirmed after Cox regression (TEVAR, HR 4.6, p= 0.046). Intervention for CBAD can be performed with excellent results, either by an open or endovascular approach. The higher rate of treatment failure after TEVAR warrants modification of current device design or endovascular approach before broad application of this treatment strategy.

Type B Aortic Dissection: A Review of Prognostic Factors and Meta-analysis of Treatment Options.

According to international guidelines, stable patients with uncomplicated Type B aortic dissection (TBAD) should receive optimal medical treatment. Despite adequate antihypertensive therapy, the long-term prognosis of these patients is characterized by a significant aortic aneurysm formation in 25-30% within four years, and survival rates from 50 to 80% at five years and 30 to 60% at 10 years. In a prospective randomized trial, preemptive thoracic endovascular aortic repair (TEVAR) in patients with chronic uncomplicated TBAD was associated with an excess early mortality (due to periprocedural hazards), but the procedure showed its benefit in prevention of aortic-specific mortality at five years of follow-up. However, preemptive TEVAR may not be the treatment of choice in all patients with uncomplicated TBAD because of the inherent periprocedural complications like stroke, paraparesis, and death, as well as stent graft-induced complications (i.e., retrograde dissection or endoleaks). Thus, the TEVAR-related deaths and complications (especially paraplegia and stroke) raise concerns that moderate the better survival with TEVAR at five years. By timely identification of those patients prone for developing complications, early intervention, preferably in the subacute or early chronic phase, may improve the overall long-term outcome for these patients. Therefore, early detectable and reliable prognostic factors for adverse events are essential to stratify patients who can be treated medically and those who will benefit from rigorous follow-up and, in the long-term, from timely, or even prophylactic, TEVAR. Several studies have identified prognostic factors in TBAD such as aortic diameter, partial false lumen thrombosis, false lumen thickness, and location of the primary entry tear. Combining these clinical and radiological predictors may be essential to implement a patient-specific approach designed to intervene only in those patients who are at high risk of developing complications to improve the long-term outcomes of patients with uncomplicated Type B aortic dissection.

Open surgical repair for chronic type B aortic dissection: a systematic review.

The treatment of chronic type B aortic dissection (CBAD) remains complicated. Thoracic endovascular aortic repair (TEVAR) has supplanted open surgical repair (OSR) as the preferred surgical treatment for CBAD. Despite TEVAR's superior short-term results, much less is understood about its long-term outcomes. As much of the understanding of OSR originates from historical report, contemporary series, with modern surgical techniques and technologies, may present an alternative to TEVAR. The present systematic review will assess the short- and long-term outcomes of historic and contemporary series of OSR for CBAD. Electronic searches were performed using six databases from their inception to March 2014. Relevant studies with OSRs for chronic type B dissection were identified. Data were extracted by two independent reviewers and analyzed according to predefined clinical endpoints. Studies were sub-classified into the pre-endovascular (historic series) and endovascular era (contemporary series) depending on whether the majority of cases were performed after 1999. Nineteen studies were identified for inclusion for quantitative analysis. Pooled short-term mortality was 11.1% overall, and 7.5% in the nine contemporary studies. Stroke, spinal cord ischemia, renal dysfunction, and reoperation for bleeding were 5.9%, 4.9%, 8.1%, and 8.1%, respectively, for the contemporary series. Absolute late reintervention was identified in 13.3% of patients overall, and in 11.3% of patients in the contemporary series. Aggregated survival at 1-, 3-, 5-, and 10-years of all patients were 82.1%, 74.1%, 66.3%, and 50.8%, respectively. OSR for chronic type B dissection in the contemporary era offers acceptable results. Management approaches should be considered carefully, taking into account both short-term and long-term complications. More research is required to clarify specific indications for OSR and TEVAR in chronic type B dissections.

Lower limb malperfusion in type B aortic dissection: a systematic review.

Lower limb malperfusion (LLM) syndrome occurs in up to 40% of complicated type B aortic dissections (TBAD) and in up to 71% of TBAD with malperfusion syndrome. This syndrome is associated with higher 30-day mortality. The aim of this systematic review was to provide clinical and procedural data of patients with LLM syndrome secondary to TBAD. The PubMed database was systematically searched from January 2000 to June 2014 for English-language publications reporting on demographic data of patients with LLM secondary to TBAD. A total of 29 papers were included (10 original articles and 19 case reports), reporting on a total of 138 patients (mean age =58±12 years; male =87%). Lower limb complications developed in acute and chronic TBAD in 134 (97%) and 4 (3%) cases, respectively. LLM presented with acute limb ischemia in 120 (87%) patients. Bilateral clinical presentation occurred in 56% (40/72) of cases. LLM was the only clinically detected malperfusion in 52% of cases (44/84). In 40% (35/84) and 25% (21/84) of cases, LLM was clinically associated with renal and visceral malperfusion, respectively. Radiological imaging showed renal, celiac trunk and superior mesenteric artery involvement in 53% (47/88), 31% (27/88) and 34% (30/88) of cases, respectively. Medical, surgical and endovascular treatments were performed in 22 (16%), 51 (37%) and 65 (47%) patients, respectively. Thirty-day morbidity was 31% (13/42) and 46% (6/13) following surgical and endovascular treatment, respectively. Thirty-day mortality was 14% (5/36) and 8% (2/26) following surgical and endovascular treatment, respectively. LLM syndrome secondary to TBAD usually developed during the acute phase and, in most cases, presented with acute limb ischemia. Bilateral clinical presentation occurred in more than half of cases. Renal and visceral malperfusion were frequently associated with lower limb flow reduction but LLM was the only clinically detected malperfusion in more than half of patients. Surgical fenestration was burdened with significant complication rates and 30-day mortality. Endovascular procedures showed lower mortality but complication rates remained high.

Current management and outcome of chronic type B aortic dissection: results with open and endovascular repair since the advent of thoracic endografting.

Thoracic endovascular aortic repair (TEVAR) has become the preferred treatment for chronic type B aortic dissection (CTBAD) at our institution. However, it remains incapable of treating all patients with CTBAD. The present study aims to review our contemporary results with open and endovascular CTBAD repairs since the advent of thoracic endografting. The records of all patients undergoing index repair of CTBAD (chronic DeBakey type IIIA, IIIB and repaired type I) at our institution between June 2005 and December 2013, were retrospectively reviewed. A total of 107 patients underwent CTBAD repair, of whom 70% (n=75) underwent endovascular-based procedures [44 TEVAR, 27 hybrid arch and four hybrid thoracoabdominal aortic aneurysm (TAAA) repair] and 30% (n=32) underwent open procedures (nine open descending and 23 open TAAA). Connective tissue disease (CTD), prior aortic surgery and DeBakey dissection type were strongly associated with the choice of operation. The rates of stroke, paraplegia and operative mortality following endovascular-based repairs were 0%, 0% and 4% (n=3), respectively. Adverse neurologic events were higher following open repair, and rates of stroke, paraplegia, and operative mortality were 16% (n=5), 9% (n=3), and 6% (n=2), respectively. However, 1- and 5-year survival rates were similar for endovascular-based repairs (86% and 65%, respectively), and open repairs (88% and 79%, respectively). Over a median follow-up interval of 34 months, the rate of descending aortic reintervention was 24% (n=18) following endovascular-based repairs and 0% following open repairs (P=0.001). Forty-four percent (n=8) of descending aortic reinterventions were required to treat stent graft complications (five endoleak, two stent graft collapse and one stent graft-induced new entry tear) and the remainder were required to treat metachronous pathology (n=2) or progressive aneurysmal disease related to persistent distal fenestrations (n=8). Endovascular repair of CTBAD was associated with excellent procedural and survival outcomes, but at the expense of further reinterventions. Open repair remains relevant for patients who are not candidates for endovascular repair and was associated with higher procedural morbidity but similar overall survival and fewer reinterventions.

RR1. A Propensity Adjusted Analysis of Open and Endovascular Thoracic Aortic Repair for Chronic Type B Dissection: A 20-Year Evaluation

Background. Optimal treatment of chronic type B aortic dissection (CBAD), whether open (open descending aortic repair, OAR) or endovascular (thoracic endovascular aortic repair, TEVAR), is controversial, suggesting a comparative analysis is warranted. Methods. One hundred twenty-two of 1,049 patients (1993 to 2013) undergoing descending aortic repair required intervention for CBAD 29.2 ± 34.9 months after the initial acute event and formed the study cohort (mean age 59.7 years). Those with degenerated residual type A dissection were excluded (n[ 65). Eighty-eight had extent IIIB CBAD; 11 had intramural hematoma. Indications for surgery included aneurysmal degeneration (n [ 105), rupture (n [ 8), acute or chronic dissection (n [ 8), and extension of dissection (n [ 1). Open strategy included descending (n [ 71) and thoracoabdominal repair (n [ 19), with hypothermic circulatory arrest used in 70 patients. The TEVAR was performed with (n [ 2) or without (n [ 30) visceral debranching. A treatment strategy propensity score incorporating time since initial acute event, CBAD extent, year of intervention, age, and selected comorbidities was constructed for multivariable analysis. Results. Early outcome included the following: 30-day mortality 4% (n [ 5); stroke 2% (n [ 2); permanent

Outcomes of open surgical repair for chronic type B aortic dissections

Open surgical repair (OSR) for chronic type B aortic dissection (CTBAD) has an associated morbidity and mortality. The role of thoracic endovascular aortic repair (TEVAR) in CTBAD has not been determined. We analyzed our contemporary experience of CTBAD undergoing OSR to identify high-risk patients who may be considered for TEVAR. From 1999 to 2010, 221 patients had repair of descending thoracic and thoracoabdominal aortic aneurysms, including 86 patients with CTBADs. We analyzed this cohort for mortality, complications, length of stay, and reinterventions. OSR was performed in 25 (29%) and 61 (71%) patients for descending thoracic and thoracoabdominal CTBAD, respectively. Median age was 57.0 years (interquartile range [IQR], 52.0-64.2 years), and median diameter was 6.0 cm (IQR, 5.0-6.9 cm). Fifty-nine patients (69%) were male. Eight (9%) were treated for rupture. Follow-up duration was 4.6 years (IQR, 2.8-6.9 years). Hospital mortality occurred in five patients (5.8%). Cardiopulmonary bypass was used in 83 patients (97%) and deep hypothermic arrest in 36 (42%). Two patients (2.3%) each developed paraplegia, stroke, and renal failure requiring permanent hemodialysis in the postoperative period. Length of stay was 13.5 days (IQR, 10.0-21.0 days). Univariate predictors of hospital death included redo operations and prolonged pump time (P < .05). Six patients (7%) had aortic-related reoperations at 4.3 years (IQR, 2.7-5.2 years): one for an ascending aortic aneurysm and five for descending aortic aneurysms. Overall survival at 1, 5, and 7 years was 92%, 83%, and 70%, respectively, and freedom from reoperation was 99%, 90%, and 86%, respectively. OSR of CTBAD is a durable option with low mortality. Patients requiring redo operations or anticipated prolonged pump time need further evaluation to determine whether conventional OSR or TEVAR, if feasible, is the optimal treatment option.

Outcomes of Open Surgical Repair for Chronic Type B Aortic Dissections

Open surgical repair (OSR) for chronic type B aortic dissections (CTBAD) has an associated morbidity and mortality. The role of thoracic endovascular aneurysm repair (TEVAR) in CTBAD has not been determined. We analyzed our contemporary experience of CTBAD undergoing OSR to identify high-risk patients that may be considered for TEVAR. From 1999-2010, 221 patients had repair of descending thoracic and thoracoabdominal aortic aneurysms, including 86 patients with CTBAD. We analyzed this cohort for mortality, complications, length of stay, and reinterventions. OSR was performed in 25 (29%) and 61 (71%) patients for descending thoracic and thoracoabdominal CTBAD, respectively. Mean age was 58.4 years (±10.4) and mean diameter 6.2 cm (±1.1, 4.1-10.0). Fifty-nine (69%) patients were male. Eight (9%) were treated for rupture. Mean duration of follow-up was 5.2 years (±2.7). Hospital mortality occurred in five (5.8%) patients. Cardiopulmonary bypass was used in 83 (97%) and deep hypothermic arrest in 36 (42%) patients. Paraplegia occurred in two (2.3%), stroke in two (2.3%), and renal failure requiring permanent hemodialysis in two (2.3%) patients. Average length of stay was 19.6 days (±17.8). Univariate predictor of hospital mortality included redo-operations and prolonged pump time (P < .05). Maximum aneurysm diameter and rupture at presentation trended toward significance. Twenty (24.7%) patients of the 81 survivors died during follow-up (mean, 62.5 ± 36 months). Six patients (7%) had aortic related reoperations at a mean of 3.8 years (±1.8): one for ascending and five for descending aortic aneurysms. Overall survival at 1, 5, and 7 years was 92%, 83%, and 70%, respectively. Freedom from reoperation was 99%, 90%, and 86%, respectively. OSR of CTBAD is a durable option with low mortality. Patients requiring redo-operations or anticipated prolonged pump time need further evaluation to determine whether conventional OSR or TEVAR, if feasible, is the optimal treatment option.

Optimal treatment for patients with chronic Stanford type B aortic dissection: endovascularly, surgically or both?†

Patients with chronic Stanford type B aortic dissections (TBAD) are traditionally treated medically, but some of the affected thoracic and thoracoabdominal aortic segments progress to large aneurysms with a significant risk of rupture. The purpose of this study is to retrospectively evaluate, with an 'all-comers' approach, the survival and the outcome of patients following thoracic endovascular aortic repair (TEVAR) or conventional open surgery for chronic TBAD as a first-line therapy or a secondary option after failed medical treatment. Between January 2000 and May 2010, 80 consecutive patients (59 males, median age 63, inter-quartile range (IQR) 55-69) suffering from chronic TBAD were treated at our institution. Thirty-three were treated medically (Group A, median age: 65, IQR: 58.5-71.5), 32 received TEVAR (Group B, median age: 62, IQR: 54-67.5) and 15 patients underwent conventional open surgery (Group C, median age: 61, IQR: 54-66). The median follow-up was 42 months (range: 0.1-124.7) and 100% complete. There were no significant differences with regard to age, gender and associated comorbidities between the treatment groups. The overall hospital mortality for chronic TBAD was 6.3% (n = 5); in-hospital mortalities for Groups A, B and C were 3.0, 6.2 and 13.4%, respectively. The incidence of major complications, such as paraplegia, malperfusion, renal failure and cardiac arrhythmia, did not significantly differ between the three groups. Postoperative stroke occurred more often after conventional open surgery (Group C: 13.3%; P = 0.07). Reintervention for TBAD pathology was required in Groups A, B and C in 12.1, 28.1 and 0%, respectively (P = 0.03). Secondary open surgery post-TEVAR was required in 7 cases (21.8%) with no postoperative paraplegia. Open surgery for extensive thoracic and thoracoabdominal repair in chronic TBAD may be performed with acceptable early and mid-term outcomes. TEVAR for aortic complications in patients with chronic dissection may be successfully performed as a first-stage procedure in order to stabilize the patient and serve as a 'bridge' to secondary open surgery. However, close surveillance is mandatory for the timely detection of aneurysm enlargement, malperfusion or impending rupture after TEVAR.

Elective Matsui-Kitamura Stent Graft Repair for Descending Thoracic Aortic Aneurysm and Chronic Type-B Aortic Dissection

The position of thoracic endovascular aortic repair (TEVAR) compared to open surgery of the thoracic aorta has changed. This study evaluates outcomes after TEVAR performed electively using our original Matsui-Kitamura stent graft (MKSG) to treat descending thoracic aortic aneurysms (dTAA) and chronic type-B aortic dissection (type-B AD), and elucidates the risk factors for postoperative spinal cord ischemia (SCI). TEVAR was performed using an MKSG in 66 patients (age: 70.8+/-9.2 years). The underlying etiology was atherosclerotic change in 39 patients, chronic type-B aortic dissection in 23 patients, and other in 4 patients. No perioperative deaths occurred. Three patients showed temporary paralysis due to postoperative SCI. Abdominal aortic aneurysm (AAA) surgery was a risk factor for postoperative SCI (P=0.04). The 5-year survival rate was 81.2%. The present study demonstrated that TEVAR of patients with dTAA and chronic type-B AD using an MKSG can be performed with high technical success rates and low rates of severe acute complications. AAA surgery was a risk factor for postoperative SCI.

Endovascular Repair of Stanford Type B Aortic Dissection: Early and Mid-term Outcomes of 121 Cases

Objective: To analyse the early and mid-term outcomes of endovascular repair of Stanford type B aortic dissection (B-AD) and to compare the outcomes between acute type B aortic dissection (AAD) and chronic type B aortic dissection (CAD). Methods: The cohort included 121 consecutive patients undergoing endovascular repair for AAD (group A, n = 72) and CAD (group B, n = 49) between January 2001 and December 2006. Follow-up with clinical examinations and computed tomography (CT) was performed post-intervention at 1, 6 and 12 months, and then yearly thereafter. Results: In groups A and B, respectively, the procedure success rates were 88.9% and 77.6%; the rates of postoperative endoleak were 11.1% and 22.4%; the 30-day mortality rates were 1.4% and 8.2%; and the 30-day stroke rates were 4.2% and 2.0%. No postoperative spinal cord ischaemia (SCI) was observed. The mean follow-up periods for groups A and B were 14.4 ± 11.0 months and 22.1 ± 20.8 months, respectively. Late mortality was 1.5% in group A and 4.8% in group B. In group A, the rates of complete false lumen (FL) thrombosis at 1 month, 1 year and 2 years postoperatively were 32.3%, 51.4% and 53.8%, respectively, and in group B, 26.2%, 44.8%, and 50.0%, respectively. Conclusion: Endovascular repair is feasible for both AAD and CAD, with favourable short- and mid-term outcomes.

Endovascular Repair of Stanford Type B Aortic Dissection: Early and Mid-term Outcomes of 121 Cases

To analyse the early and mid-term outcomes of endovascular repair of Stanford type B aortic dissection (B-AD) and to compare the outcomes between acute type B aortic dissection (AAD) and chronic type B aortic dissection (CAD). The cohort included 121 consecutive patients undergoing endovascular repair for AAD (group A, n=72) and CAD (group B, n=49) between January 2001 and December 2006. Follow-up with clinical examinations and computed tomography (CT) was performed post-intervention at 1, 6 and 12 months, and then yearly thereafter. In groups A and B, respectively, the procedure success rates were 88.9% and 77.6%; the rates of postoperative endoleak were 11.1% and 22.4%; the 30-day mortality rates were 1.4% and 8.2%; and the 30-day stroke rates were 4.2% and 2.0%. No postoperative spinal cord ischaemia (SCI) was observed. The mean follow-up periods for groups A and B were 14.4+/-11.0 months and 22.1+/-20.8 months, respectively. Late mortality was 1.5% in group A and 4.8% in group B. In group A, the rates of complete false lumen (FL) thrombosis at 1 month, 1 year and 2 years postoperatively were 32.3%, 51.4% and 53.8%, respectively, and in group B, 26.2%, 44.8%, and 50.0%, respectively. Endovascular repair is feasible for both AAD and CAD, with favourable short- and mid-term outcomes.

How to Guide Stent-Graft Implantation in Type B Aortic Dissection?

Despite growing interest in stent-graft implantation for type-B aortic dissection, there are no established recommendations to prepare and perform an implantation procedure. We directly compared angiography (ANGIO), transesophageal echocardiography (TEE), and intravascular ultrasound (IVUS) intraprocedually before and after placement of 48 stent grafts in 42 consecutive patients (12 women, 61+/-11 years of age) with acute and chronic type-B aortic dissection for both usefulness and capability to guide aortic stent-graft implantation. Both IVUS and TEE are superior to ANGIO to identify multiple entries (52 and 43 versus 34; P<0.005 each), to diagnose false-lumen slow flow after stent-graft implantation (32 and 31 versus 24; P<0.005 each) and to detect incomplete stent apposition (18 and 16 versus 8; P<0.005 each). In comparison with ANGIO, guide wire position over the entire length of the aorta was documented more frequently by TEE and IVUS (40 and 42 versus 25; P<0.001 each). In 4 patients with abdominal extension of the dissection, only IVUS was able to accurately identify the false lumen over the entire length of the diseased aorta. TEE was superior to IVUS and ANGIO in the detection of endoleaks (5 versus 0 and 1; P<0.05 each). Intraprocedural ANGIO, TEE, and IVUS had been performed without complications in all patients. TEE in conjunction with ANGIO appears to be advantageous and adds incremental information to safely guide stent-graft placement in type-B aortic dissection. Additional use of IVUS was found to be helpful in patients with complex anatomy and abdominal extension of the dissection.