Long-term follow-up of acute type B aortic dissection: Ulcer-like projections in thrombosed false lumen play a role in late aortic events

Coil Embolization for a New Ulcer-Like Projection Near the Distal Anastomosis After a Hemiaortic Arch Replacement

Ulcer-like projections (ULPs) with a tendency to enlarge are at risk of aortic events such as new dissection, aneurysmal formation, or rupture and require therapeutic intervention. However, what should be done after open chest surgery when standard thoracic endovascular aortic repair (TEVAR) cannot be performed is debatable. Here, we present a case of coil embolization of a newly enlarged ULP that was not amenable to TEVAR following a hemiarch aortic arch repair. A 68-year-old male with a history of ascending and hemiaortic arch repair for acute type A aortic dissection presented with a chief complaint of chest pain three months prior to presentation. A post-type A dissection ULP remained in the aortic arch but had enlarged over the three months. Therapeutic intervention was planned to avoid aortic events; however, standard and fenestrated TEVAR were going to be anatomically challenging. Since the patient was in poor general condition after diverticulitis and stroke, reopened total arch replacement and total debranching TEVAR were avoided. The neck of the ULP was narrow and had a small volume; therefore, we assessed that the coil-packing method could embolize the ULP. Coil embolization was successful, and the patient had no postoperative complications. A computed tomography scan at the remote stage showed no recanalization or enlargement, and the patient was stable. Coil embolization may be attempted for arch ULP that can enlarge if the ULP can be embolized with intra-aneurysmal packing when it is difficult to perform a reopen surgery or TEVAR, including standard zone II, total debranching, and fenestrated TEVAR.

Long-term outcomes of primary surgical repair for communicating DeBakey IIIb chronic dissecting aortic aneurysm

Objective

This study aimed to evaluate the long-term outcomes of surgical strategies for communicating DeBakey IIIb chronic dissecting aortic aneurysm, considering the optimal primary surgical repair to prevent aortic events.

Methods

From 2002 to 2021, 101 patients with communicating DeBakey IIIb chronic dissecting aortic aneurysm who underwent surgical repair were categorized based on the primary surgical repair: 1-stage repair of thoracoabdominal aortic aneurysm (TAAAR) (n = 22) or staged repair, such as descending thoracic aneurysm repair (DTAR) (n = 43) or total arch replacement with elephant trunk implantation (TARET) (n = 25), and thoracic endovascular aortic repair (TEVAR) (n = 11). Early and late postoperative outcomes were compared among the groups.

Results

Early outcomes for TAAAR, DTAR, TARET, and TEVAR were associated with the incidence of stroke (9.1% vs 0% vs 4.0% vs 9.1%, respectively), spinal cord injury (13.6% vs 4.7% vs 8.0% vs 0%, respectively), and in-hospital mortality (9.1% vs 2.3% vs 0% vs 9.1%, respectively). During follow-up, the 10-year overall survival and 7-year aortic event-free rates for TAAAR, DTAR, TARET, and TEVAR were 61.8%, 71.6%, 21.5%, and 26.5% and 93.8%, 84.3%, 74.4%, and 51.4%, respectively. TAAAR had significantly higher overall survival (P = .05) and aortic event-free rates (P = .03) than TEVAR. TARET (hazard ratio, 2.27; P < .01) and TEVAR (hazard ratio, 3.40; P < .01) were independently associated with the incidence of aortic events during follow-up.

Conclusions

Considering the optimal primary surgical repair based on long-term outcomes, TEVAR was not a durable treatment option. Patient-specific TAAAR or DTAR should be considered rather than defaulting to minimally invasive primary repairs for all patients with communicating DeBakey IIIb chronic dissecting aortic aneurysm.

Growth and remodeling of the dissected membrane in an idealized dissected aorta model

While transitioning from the acute to chronic phase, the wall of a dissected aorta often expands in diameter and adaptations in thickness and microstructure take place in the dissected membrane. Including the mechanisms, leading to these changes, in a computational model is expected to improve the accuracy of predictions of the long-term complications and optimal treatment timing of dissection patients. An idealized dissected wall was modeled to represent the elastin and collagen production and/or degradation imposed by stress- and inflammation-mediated growth and remodeling, using the homogenized constrained mixture theory. As no optimal growth and remodeling parameters have been defined for aortic dissections, a Latin hypercube sampling with 1000 parameter combinations was assessed for four inflammation patterns, with a varying spatial extent (full/local) and temporal evolution (permanent/transient). The dissected membrane thickening and microstructure was considered together with the diameter expansion over a period of 90 days. The highest success rate was found for the transient inflammation patterns, with about 15% of the samples leading to converged solutions after 90 days. Clinically observed thickening rates were found for 2-4% of the transient inflammation samples, which represented median total diameter expansion rates of about 5 mm/year. The dissected membrane microstructure showed an elastin decrease and, in most cases, a collagen increase. In conclusion, the model with the transient inflammation pattern allowed the reproduction of clinically observed dissected membrane thickening rates, diameter expansion rates and adaptations in microstructure, thus providing guidance in reducing the parameter space in growth and remodeling models of aortic dissections.

Ulcer-like projections into the dilated false lumen after stent-graft placement for aortic dissection: A case report

RATIONALE

Acute type A aortic dissection and chronic type B aortic dissection (TBAD) occurs simultaneously in rare cases. Although the development of ulcer-like projection (ULP) is associated with an increase in adverse aorta-related events, the false-lumen enlargement caused by the ULP progression is uncommon.

PATIENT CONCERNS

A 72-year-old female with chronic TBAD was admitted to our unit with back and chest pain. Computed tomography revealed acute type A aortic dissection and a hematoma caused by rupturing of the descending aorta due to chronic TBAD. After endovascular intervention, the false lumen thrombosed and shrunk.

DIAGNOSIS

After 9 months, a developing ULP, which projected into a dilating false lumen, was found. An impending ruptured descending aortic aneurysm was confirmed.

INTERVENTIONS

Emergency Total arch replacement and thoracic endovascular aortic repair (TEVAR) was performed.

OUTCOMES

The procedure was successful. One year later, regular follow-up showed that the false lumen had completely shrunk.

LESSONS

ULP can arise and cause progressive dilation of false lumen after TEVAR. Careful and regular computed tomography examinations are required for early diagnosis of false lumen becoming thrombosed after TEVAR. Close follow-up and timely intervention, including TEVAR, should be considered in cases of aortic enlargement due to a newly developed ULP.

Postoperative Maximal Aortic Diameter is a Significant Predictor of Dilation of the Residual Dissected Aorta after Aortic Replacement for Acute Debakey Type I Aortic Dissection

BACKGROUND

This study investigated the impact of aortic diameter on late aortic dilation of the residual dissected aorta after tear-oriented aortic replacement for acute DeBakey type I aortic dissection.

METHODS

Of 133 patients who underwent aortic replacement for acute DeBakey type I/II aortic dissection between 2008 and 2019, 45 patients with a residual dissected aorta after surgery for acute DeBakey type I aortic dissection and who underwent computed tomography at predischarge and after 1 year were retrospectively assessed. The aortic diameter and false lumen area were measured at 3 levels: the maximal aortic site, seventh thoracic vertebra, and celiac axis. Multivariable Cox regression analysis was employed to identify the predictors of late aortic dilation, defined as an aortic growth rate of ≥5 mm/year or a maximal aortic diameter of ≥55 mm.

RESULTS

During a median follow-up of 75 [range: 13-152] months, 6 patients (5 men; mean age: 57 ± 14 years) experienced aortic dilation. All 6 patients had the maximal aortic diameter between the distal aortic arch and seventh thoracic vertebra level at the last computed tomography. Multivariable Cox regression analysis showed that the predischarge maximal aortic diameter was an independent determinant of late aortic dilation (hazard ratio: 2.28/mm, 95% confidence interval: 1.10-5.86).

CONCLUSIONS

Predischarge maximal aortic diameter is a significant predictor of late aortic dilation in patients with a residual dissected aorta after tear-oriented surgical repair of acute DeBakey type I aortic dissection.

Acute medical management of aortic dissection

Acute aortic dissection is a life-threatening disease. Current therapeutic guidelines recommend medical therapy with aggressive blood pressure lowering for patients with acute aortic dissection, when they are not indicated for emergency surgery. In particular, patients with aortic dissection without ascending aorta involvement (Stanford type B) are treated medically, unless they have fatal complications. Patients with type B aortic dissection who have critical complications have higher early mortality than that in patients without complications. However, recent advances in thoracic endovascular aortic repair can improve the clinical outcomes in such patients. Accordingly, current guidelines recommend thoracic endovascular aortic repair for patients with complicated type B aortic dissection. However, patients with visceral ischemia still have a poor prognosis, even when they are treated with thoracic endovascular aortic repair; an early diagnosis and intervention is crucial to prevent mortality. Understanding the pathophysiological anatomy that can induce organ malperfusion might be important for an early diagnosis and intervention. This review summarizes the current state of acute medical management in patients with acute aortic dissection, based on current evidence and expert consensus, focusing on patients with type B aortic dissection.

Current evidence in predictors of aortic growth and events in acute type B aortic dissection

OBJECTIVES

Acute type B aortic dissection can have a stable course or evolve into aneurysm and subsequent adverse events. The aim of this systematic review was to analyze the morphologic predictors of an adverse course to establish their validity based on consistency of results.

METHODS

Fifty-one studies were included in this review, reporting on aortic size, false lumen (FL) size, primary entry tear (ET) size and location, status of FL thrombosis, number of ETs, branch vessels involvement, and FL longitudinal extent.

RESULTS

Some predictors showed good consistency, whereas others did not. Aortic size was the most investigated predictor. A larger diameter at presentation predicted worse outcomes, with few exceptions. Both FL size and size relative to true lumen size also predicted an adverse course, although a standardized measurement method was not used. Regarding primary ET size and location, evidence was sparse and somewhat conflicting. Although FL complete thrombosis was consistently associated with a more benign course, the role of partial thrombosis remained unclear and the concept of FL saccular formation might account for the inconsistency, but further evidence is needed. A higher number of re-entry tears was considered to be protective against false channel expansion, but results need to be confirmed. The predictive role of branch vessels involvement and FL longitudinal extent remain controversial.

CONCLUSIONS

Among several predictors of aortic growth and events in acute type B aortic dissection, controversial and even conflicting results have been described. Consistent evidence has been demonstrated only for two predictors: aortic size at presentation is associated with adverse events and total FL thrombosis has a protective role.

The incidence of delayed complications in acute type B aortic dissections is underestimated

OBJECTIVE

Acute type B aortic dissections (TBADs) can have immediate or delayed complications within the first 2 weeks. Because the majority of clinical series retrospectively categorized TBAD, the incidence and outcome of delayed complications in initially uncomplicated TBAD within the first 14 days are not well described.

METHODS

We retrospectively analyzed 86 patients (78% male; age, 62.5 ± 13 years) with acute TBAD treated consecutively between January 2004 and May 2016 at a tertiary referral center. All TBADs were confirmed by computed tomography angiography (CTA) on admission, after 2 to 5 days, and after 10 to 14 days. Study end points were the incidence of immediate and delayed complications (aortic rupture, malperfusion, rapid aortic expansion >4 mm, pain or hypertension resistant to medical therapy) and in-hospital mortality. In addition, we looked at CTA-detected morphometric variables (maximum diameters of descending aorta, false lumen [FL], and primary entry tear; number of intimal tears; FL configuration; true lumen collapse; course of the dissection) and their association with delayed complications. Finally, we assessed treatment modalities and clinical outcomes.

RESULTS

Of all TBADs, 22 (26%) presented with immediate complications (rupture, n = 11); 64 patients (74%) were initially assessed as having uncomplicated TBAD. Of these 64 patients, 24 (28% of all 86) suffered from delayed complications (malperfusion, n = 10; aortic rupture, n = 3; early expansion >4 mm, n = 8; refractory pain, n = 2; uncontrollable hypertension, n = 1) at a median interval of 7.1 (2-14) days after symptom onset. During the first 14 days, 40 patients (46%) remained uncomplicated. The CTA analysis revealed a significant association of initial thoracic aortic diameter (P = .009), size of the primary entry tear (P = .018), true lumen collapse (P = .019), and partially thrombosed FL (P = .019) with the occurrence of delayed complications within the first 14 days. Of the patients with delayed complications, 87.5% underwent surgery (90% thoracic endovascular aortic repair, 10% peripheral revascularization); 12.5% in this group died following aortic rupture before they received surgical repair. The mortality of patients with delayed complicated TBAD was significantly higher compared with those who remained uncomplicated within the 14-day period (12.5% vs 0%; P = .0221).

CONCLUSIONS

Delayed complications in initially uncomplicated acute TBAD are not infrequent. Morphologic variables like maximum diameter of the descending aorta, primary entry tear, true lumen collapse, and partially thrombosed FL were associated with an increased risk of delayed complications in initially uncomplicated TBAD. Future clinical research must verify the predictive role of clinical and morphologic variables in the acute phase, particularly with regard to a possible early surgical treatment to prevent a fatal outcome.

Conservative management versus endovascular or open surgery in the spectrum of type B aortic dissection

Background

Type B aortic dissection is a life-threatening acute aortic condition often with acute ischemic signs or symptoms. With initial management focusing on alleviating malperfusion and pain, and avoiding propagation of dissection or rupture both systolic blood and pulse pressure should be reduced initially by an aggressive medical approach. In the setting of persistent signs of complications endovascular strategies have replaced open surgery and led to a fourfold increase in early survival and better long-term outcomes.

Methods

An electronic health database search was performed on articles published between January 2006 and July 2017. Publications were included in this review if (I) the index aortic pathology was type B aortic (distal) dissection; (II) when medical management, open surgical replacement or thoracic endovascular aortic repair were among those options; (III) when at least one of all basic outcome criteria such as survival, spinal cord ischemia and cerebrovascular accident was reported; (IV) when ≥15 serial patients were included. A total of 62 studies were eligible and analysed.

Results

Our manuscript has summarized data collected over 12 years on management specific outcomes in the setting of distal aortic dissection and provides an up-to-date interpretation of the published evidence. For complicated cases, treated acutely, the 30-day or in-hospital mortality was 7.3% when managed by endovascular means, whereas the pooled rate for 30-day or in-hospital mortality was 19.0% when subjected to open repair. For acute uncomplicated type B dissection usually treated with blood pressure lowering medications, the pooled 30-day or in-hospital mortality rate was 2.4%. Survival rates at 5 years averaged at 60% (40% mortality). Freedom from any aortic event ranged from 34.0% to 83.9%, underlining an inherent risk of progression and late complications. For chronic complicated type B dissection, the rates of stroke, paraplegia and operative mortality following endovascular repair ranged from 5% to 13%, 2% to 13% and 2 to 13%, respectively, while 5-year survival rates after open repair ranged from 60% to 90%. In chronic uncomplicated type B dissection almost 90% of patients survive initial hospitalization and were subjected to medical management with a 5-year survival of 50-80%. However, up to 20-55% of medically treated patients develop aneurysmal degeneration after 5 years with an unknown risk of rupture.

Conclusions

Currently, the less invasive strategy of endovascular repair (as compared to open surgery) provides improved 30-day or in-hospital survival in the setting of complicated acute type B aortic dissection and may seek broad application. Open surgical aortic reconstruction should be left to experienced aortic centres if endovascular management is not an option.

Update on the Therapeutic Strategy of Type B Aortic Dissection

Stanford type B aortic dissection (TBAD) is a life-threatening disease. Current therapeutic guidelines recommend medical therapy with aggressive blood pressure lowering for patients with acute TBAD unless they have fatal complications. Although patients with uncomplicated TBAD have relatively low early mortality, aorta-related adverse events during the chronic phase worsen the long-term clinical outcome. Recent advances in thoracic endovascular aortic repair (TEVAR) can improve clinical outcomes in patients with both complicated and uncomplicated TBAD. According to present guidelines, complicated TBAD patients are recommended for TEVAR. However, the indication in uncomplicated TBAD remains controversial. Recent results of randomized trials, which compared the clinical outcome in patients treated with optimal medical therapy and those treated with TEVAR, suggest that preemptive TEVAR should be considered in uncomplicated TBAD with suitable aortic anatomy. However, these trials failed to show improvement in early mortality in patients treated with TEVAR compared with patients treated with optimal medical therapy, which suggest the importance of patient selection for TEVAR. Several clinical and imaging-related risk factors have been shown to be associated with early disease progression. Preemptive TEVAR might be beneficial and should be considered for high-risk patients with uncomplicated TBAD. However, an interdisciplinary consensus has not been established for the definition of patients at high-risk of TBAD, and it should be confirmed by experts including physicians, radiologists, interventionalists, and vascular surgeons. This review summarizes the current understanding of the therapeutic strategy in patients with TBAD based on evidence and expert consensus.

Prognostic significance of early aortic remodeling in acute uncomplicated type B aortic dissection and intramural hematoma

BACKGROUND

Patients with Stanford type B aortic dissections (ADs) are at risk of long-term disease progression and late complications. The aim of this study was to evaluate the natural course and evolution of acute type B AD and intramural hematomas (IMHs) in patients who presented without complications during their initial hospital admission and who were treated with optimal medical management (MM).

METHODS

Databases from 2 aortic centers in Europe and the United States were used to identify 136 patients with acute type B AD (n = 92) and acute type B IMH (n = 44) who presented without complications during their index admission and were treated with MM. Computed tomography angiography scans were available at onset (≤14 days) and during follow-up for those patients. Relevant data, including evidence of adverse events during follow-up (AE; defined according to current guidelines), were retrieved from medical records and by reviewing computed tomography scan images. Aortic diameters were measured with dedicated 3-dimensional software.

RESULTS

The 1-, 2-, and 5-year event-free survival rates of patients with type B AD were 84.3% (95% confidence interval [CI], 74.4-90.6), 75.4% (95% CI, 64.0-83.7), and 62.6% (95% CI, 68.9-73.6), respectively. Corresponding estimates for IMH were 76.5% (95% CI, 57.8-87.8), 76.5% (95% CI, 57.8-87.8), and 68.9% (95% CI, 45.2-83.9), respectively. In patients with type B AD, risk of an AE increased with aortic growth within the first 6 months after onset. A diameter increase of 5 mm in the first half year was associated with a relative risk for AE of 2.29 (95% CI, 1.70-3.09) compared with the median 6 months' growth of 2.4 mm. In approximately 60% of patients with IMH, the abnormality resolved within 12 months and in the patients with nonresolving IMH, risk of an adverse event was greatest in the first year after onset and remained stable thereafter.

CONCLUSIONS

More than one third of patients with initially uncomplicated type B AD suffer an AE under MM within 5 years of initial diagnosis. In patients with nonresolving IMH, most adverse events are observed in the first year after onset. In patients with type B AD an early aortic growth is associated with a greater risk of AE.

Operative results of the anterolateral thoracotomy with partial sternotomy approach for chronic-type B aortic dissection involving the aortic arch

Objectives

There are various treatment strategies for chronic-type B aortic dissection involving the aortic arch. Our aim was to review our surgical experience in the anterolateral thoracotomy with the partial sternotomy approach for chronic-type B aortic dissection involving the aortic arch.

Methods

From January 2000 to October 2015, 39 patients underwent the single-stage open surgery for chronic-type B aortic dissection involving the aortic arch using the anterolateral thoracotomy with partial sternotomy approach.

Results

Among the 39 patients, 32 were men (82.1%; mean age at surgery, 61.3 ± 11.9 years), with a mean dissecting aortic aneurysm diameter of 50.21 ± 12.20 mm; 28 patients (71.8%) had patent false lumens of the descending aorta. The median interval from dissection occurrence until surgery was 34.05 ± 52.34 months. Twenty-one patients underwent descending aortic replacement plus total aortic arch replacement and 18 underwent descending aortic replacement (plus partial aortic arch replacement). Overall in-hospital mortality and postoperative stroke rates were 5.1% (2 patients) and 10.3% (4 patients), respectively. Survival rates at 1, 3 and 5 years were 94.7%, 94.7% and 90.2%, respectively. Aortic event-free rates at 1, 3 and 5 years were 90.9%, 90.9% and 80.2%, respectively.

Conclusions

The anterolateral thoracotomy with partial sternotomy approach is a useful surgical procedure with acceptable outcomes for chronic-type B aortic dissection cases involving the aortic arch, when aortic remodelling using thoracic endovascular aortic repair cannot be performed.

Aortic arch pathologies - incidence and natural history

Endovascular interventions have made significant progress and are moving towards treating diseases of the aortic arch. Aortic arch pathologies incur substantial morbidity as well as short and long-term mortality but the progression is not well understood. This article reviews the current evidence on the natural history of aortic arch aneurysms and acute aortic syndromes, including penetrating ulcers, intramural hematomas, acute and chronic type B dissections. Risk factors for disease progression and mortality are also identified with special reference to vascular surgeons.

False Lumen Status in Patients With Acute Aortic Dissection: A Systematic Review and Meta-Analysis

Background

The long‐term association between the status of the false lumen and poor patient outcomes in acute aortic dissection (AAD) remains unclear. This systematic review and meta‐analysis investigated whether the status of the false lumen was a predictor of poor long‐term survival in AAD.

Methods and Results

Eleven cohort studies (2924 participants) exploring the association between the false lumen status and long‐term outcomes (>1 year) in AAD were included. All studies reported multivariate‐adjusted hazard ratios (HRs) with 95% CIs for long‐term outcomes, according to false lumen status. Pooled HRs for mortality and aortic events were computed and weighted using generic inverse‐variance and random‐effect modeling. Residual patent false lumen was an independent predictor of long‐term mortality in AAD type A (HR, 1.71; 95% CI, 1.16–2.52; P=0.007) and type B (HR, 2.79; 95% CI, 1.80–4.32; P<0.001). AAD patients with residual patent false lumen exhibited an increased risk of aortic events (HR, 5.43; 95% CI, 2.95–9.99; P<0.001). Partial false lumen thrombosis was independently associated with long‐term mortality in type B AAD (HR, 2.24; 95% CI, 1.37–3.65; P=0.001). This association was not observed in AAD type A patients (HR, 1.75; 95% CI, 0.88–3.45; P=0.211).

Conclusions

The false lumen status influences late outcomes in AAD. Residual patent false lumen is independently associated with poor long‐term survival in AAD. However, only type B AAD patients with partial false lumen thrombosis had an increased late mortality risk.

Contemporary Management Strategies for Chronic Type B Aortic Dissections: A Systematic Review

Background

Currently, the optimal management strategy for chronic type B aortic dissections (CBAD) is unknown. Therefore, we systematically reviewed the literature to compare results of open surgical repair (OSR), standard thoracic endovascular aortic repair (TEVAR) or branched and fenestrated TEVAR (BEVAR/FEVAR) for CBAD.

Methods

EMBASE and MEDLINE databases were searched for eligible studies between January 2000 and October 2015. Studies describing outcomes of OSR, TEVAR, B/FEVAR, or all, for CBAD patients initially treated with medical therapy, were included. Primary endpoints were early mortality, and one-year and five-year survival. Secondary endpoints included occurrence of complications. Furthermore, a Time until Treatment Equipoise (TUTE) graph was constructed.

Results

Thirty-five articles were selected for systematic review. A total of 1081 OSR patients, 1397 TEVAR patients and 61 B/FEVAR patients were identified. Early mortality ranged from 5.6% to 21.0% for OSR, 0.0% to 13.7% for TEVAR, and 0.0% to 9.7% for B/FEVAR. For OSR, one-year and five-year survival ranged 72.0%-92.0% and 53.0%-86.7%, respectively. For TEVAR, one-year survival was 82.9%-100.0% and five-year survival 70.0%-88.9%. For B/FEVAR only one-year survival was available, ranging between 76.4% and 100.0%. Most common postoperative complications included stroke (OSR 0.0%-13.3%, TEVAR 0.0%-11.8%), spinal cord ischemia (OSR 0.0%-16.4%, TEVAR 0.0%-12.5%, B/FEVAR 0.0%-12.9%) and acute renal failure (OSR 0.0%-33.3%, TEVAR 0.0%-34.4%, B/FEVAR 0.0%-3.2%). Most common long-term complications after OSR included aneurysm formation (5.8%-20.0%) and new type A dissection (1.7–2.2%). Early complications after TEVAR included retrograde dissection (0.0%-7.1%), malperfusion (1.3%–9.4%), cardiac complications (0.0%–5.9%) and rupture (0.5%–5.0%). Most common long-term complications after TEVAR were rupture (0.5%–7.1%), endoleaks (0.0%–15.8%) and cardiac complications (5.9%-7.1%). No short-term aortic rupture or malperfusion was observed after B/FEVAR. Long-term complications included malperfusion (6.5%) and endoleaks (0.0%-66.7%). Reintervention rates after OSR, TEVAR and B/FEVAR were 5.8%-29.0%, 4.3%-47.4% and 0.0%-53.3%, respectively. TUTE for OSR was 2.7 years, for TEVAR 9.9 months and for B/FEVAR 10.3 months.

Conclusion

We found a limited early survival benefit of standard TEVAR over OSR for CBAD. Complication rates after TEVAR are higher, but complications after OSR are usually more serious. Initial experiences with B/FEVAR show its feasibility, but long-term results are needed to compare it to OSR and standard TEVAR. We conclude that optimal treatment of CBAD remains debatable and merits a patient specific decision. TUTE seems a feasible and useful tool to better understand management outcomes of CBAD.

Outcomes of Patients With Acute Type B (DeBakey III) Aortic Dissection: A 13-Year, Single-Center Experience

Background—

Aortic dissection remains the most common aortic catastrophe. In the endovascular era, the management of acute type B aortic dissection (ATBAD) is undergoing dramatic changes. The aim of this study is to evaluate the long-term outcomes of patients with ATBAD who were treated at our center over a 13-year period.

Methods and Results—

We reviewed patients with ATBAD between 2001 and 2014, analyzing variables based on status (complicated [c] versus uncomplicated [u]) and treatment modalities. We defined cATBAD as rupture, expansion of diameter on imaging during the admission, persistent pain, or clinical malperfusion leading to a deficit in cerebral, spinal, visceral, renal, or peripheral vascular territories at presentation or during initial hospitalization. Postoperative outcomes were defined as deficits not present before the intervention. Outcomes were compared between the groups by use of Kaplan-Meier and descriptive statistics. We treated 442 patients with ATBAD. Of those 442, 60.6% had uATBAD and were treated medically, and 39.4% had cATBAD, of whom 39.0% were treated medically to 30.0% with open repair, 21.3% with thoracic endovascular aortic repair, and 9.7% with other open peripheral procedures. Intervention-free survival at 1 and 5 years was 84.8% and 62.7% for uATBAD, 61.8% and 44.0% for cATBAD-medical, 69.2% and 47.2% for cATBAD-open, and 68.0% and 42.5% for cATBAD–thoracic endovascular aortic repair, respectively (P=0.001). Overall survival was significantly related primarily to complicated presentation.

Conclusions—

In our experience, early and late outcomes of ATBAD were dependent on the presence of complications, with cATBAD faring worse. Although uATBAD was associated with favorable early survival, late complications still occurred, mandating radiographic surveillance and open or endovascular interventions. Prospective trials are required to better determine the optimal therapy for uATBAD.

Aneurysmal degeneration of the thoracoabdominal aorta after medical management of type B aortic dissections

BACKGROUND

Patients with uncomplicated type B aortic dissections who are managed medically are at risk of aortic aneurysmal degeneration over time. However, the effect of improvement in antihypertensive medications and stricter blood pressure control is unknown. The goal of this study was to determine the rate of aneurysmal degeneration in a contemporary cohort of patients with medically treated type B dissection.

METHODS

Included were all patients with acute uncomplicated type B aortic dissection who were initially managed medically between March 1999 and March 2011 and had follow-up axial imaging studies. Maximum aortic growth was calculated by comparing the initial imaging study to the most current scan or imaging obtained just before any aortic-related intervention. An increase of ≥5 mm was the threshold considered as aortic growth. Predictors of aortic aneurysmal degeneration were determined using Cox proportional hazards models.

RESULTS

We identified 200 patients (61% men) with medically managed acute type B dissections receiving multiple imaging studies. Patients were an average age of 63.4 years, and 75.5% had a history of hypertension. Mean follow-up was 5.3 years (range, 0.1-14.7 years). Mean time between the initial and final imaging studies was 3.2 years (range, 0.1-12.9 years). At 5 years, only 51% were free from aortic growth. Fifty-six patients (28%) required operative intervention (50 open, 6 endovascular repair) for aneurysmal degeneration, and the actuarial 5-year freedom from intervention was 76%. After excluding five patients (2.5%) with early rapid degeneration requiring intervention within the first 2 weeks, the mean rate of aortic growth was 12.3 mm/y for the total aortic diameter, 3.8 mm/y for the true lumen diameter, and 8.6 mm/y for the false lumen diameter. Only aortic diameter at index presentation >3.5 cm was a risk factor for future growth (odds ratio, 2.54; 95% confidence interval, 1.34-4.81; P < .01). Complete thrombosis of the false lumen was protective against growth (odds ratio, 0.19; 95% confidence interval, 0.11-0.42; P < .01).

CONCLUSIONS

Although medical management of uncomplicated acute, type B aortic dissections has been the standard of care, at 5 years, a significant number of patients will require operative intervention for aneurysmal degeneration. Further studies of early intervention (eg, thoracic endovascular aortic repair) for type B aortic dissection to prevent late aneurysm formation are needed.

Acute type B aortic dissection with communicating vs. non-communicating false lumen

BACKGROUND

In practice, patients with acute aortic dissection (AAD) are generally divided into 2 groups according to the status of the false lumen: non-communicating or communicating. The similarities and differences between the 2 groups, however, have not been fully determined in a large population. METHODS AND RESULTS: We studied 502 patients with Stanford type B AAD. Clinical background at symptom onset was compared, and similarities and differences characterized, for patients with non-communicating (NC group, n=288) vs. communicating (C group, n=214) false lumens. Time of day (00.00-06.00 hours, 06.00-12.00 hours, 12.00-18.00 hours, and 18.00-24.00 hours) and extent of physical activity (extreme exertion, slight exertion, at rest, and sleeping) at symptom onset were similar between groups. Patients in the NC group were older (mean age, 71±11 years vs. 64±14 years, P<0.01) and had lower prevalence of distally extended aortic dissection (26% vs. 8%, P<0.01) and deaths in hospital (2% vs. 7%, P=0.011) than those in the C group.

CONCLUSIONS

At symptom onset, clinical circumstances and physical activity were similar between the groups, and old age and a background of DeBakey IIIa aortic dissection may be associated with determination of false lumen status. The outcome in the NC group was better than in the C group.

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.

Management of complicated and uncomplicated acute type B dissection. A systematic review and meta-analysis

BACKGROUND

The management of acute type B dissection represents a clinical challenge. We undertook a systematic review of the available literature regarding medical, surgical and endovascular treatments of acute type B aortic dissection and combined the eligible studies into a meta-analysis.

METHODS

An extensive electronic health database search was performed on all articles published from January 2006 up to November 2013 describing the management of acute type B aortic dissection. Studies including less than 15 patients were excluded.

RESULTS

ACUTE COMPLICATED TYPE B DISSECTION: overall, 2,531 patients were treated with endovascular repair (TEVAR) and the pooled rate for 30-day/in-hospital mortality was 7.3%. The pooled estimates for cerebrovascular events, spinal cord ischemia (SCI) and total neurologic events were 3.9%, 3.1% and 7.3%, respectively. A total of 1,276 patients underwent open surgical repair and the pooled rate for 30-day/in-hospital mortality was 19.0%. The pooled rate for cerebrovascular events was 6.8%, for SCI 3.3% and for total neurologic complications 9.8%. Acute uncomplicated type B dissection: outcome of 2,347 patients who underwent conservative medical management were analyzed. The pooled 30-day/in-hospital mortality rate was 2.4%. The pooled rate for cerebrovascular events was 1%, for SCI 0.8% and for overall neurologic complications 2%.

CONCLUSIONS

Endovascular repair provides a superior 30-day/in-hospital survival for acute complicated type B aortic dissection compared to surgical aortic reconstruction. However, open repair still has a significant role as endovascular repair is not applicable in all patients and there remains concerns regarding the durability of this technique. TEVAR seems to have a more favorable outcome regarding aortic remodeling and the aortic-specific survival rate when compared with medical therapy alone. Randomized controlled trials focusing on the prognostic factors of early and late complications in uncomplicated type B dissections are needed.

Endovascular repair of acute uncomplicated aortic type B dissection promotes aortic remodelling: 1 year results of the ADSORB trial

OBJECTIVES

Uncomplicated acute type B aortic dissection (AD) treated conservatively has a 10% 30-day mortality and up to 25% need intervention within 4 years. In complicated AD, stent grafts have been encouraging. The aim of the present prospective randomised trial was to compare best medical treatment (BMT) with BMT and Gore TAG stent graft in patients with uncomplicated AD. The primary endpoint was a combination of incomplete/no false lumen thrombosis, aortic dilatation, or aortic rupture at 1 year.

METHODS

The AD history had to be less than 14 days, and exclusion criteria were rupture, impending rupture, malperfusion. Of the 61 patients randomised, 80% were DeBakey type IIIB.

RESULTS

Thirty-one patients were randomised to the BMT group and 30 to the BMT+TAG group. Mean age was 63 years for both groups. The left subclavian artery was completely covered in 47% and in part in 17% of the cases. During the first 30 days, no deaths occurred in either group, but there were three crossovers from the BMT to the BMT+TAG group, all due to progression of disease within 1 week. There were two withdrawals from the BMT+TAG group. At the 1-year follow up there had been another two failures in the BMT group: one malperfusion and one aneurysm formation (p = .056 for all). One death occurred in the BMT+TAG group. For the overall endpoint BMT+TAG was significantly different from BMT only (p < .001). Incomplete false lumen thrombosis, was found in 13 (43%) of the TAG+BMT group and 30 (97%) of the BMT group (p < .001). The false lumen reduced in size in the BMT+TAG group (p < .001) whereas in the BMT group it increased. The true lumen increased in the BMT+TAG (p < .001) whereas in the BMT group it remained unchanged. The overall transverse diameter was the same at the beginning and after 1 year in the BMT group (42.1 mm), but in the BMT+TAG it decreased (38.8 mm; p = .062).

CONCLUSIONS

Uncomplicated AD can be safely treated with the Gore TAG device. Remodelling with thrombosis of the false lumen and reduction of its diameter is induced by the stent graft, but long term results are needed.

Prognostic factors in patients with uncomplicated acute type B aortic dissection

BACKGROUND

The benefit of thoracic endovascular aortic repair (TEVAR) for uncomplicated acute type B aortic dissection is unclear. Reliable prognostic factors are needed to identify candidates for prophylactic TEVAR. The aim of this study was to detect prognostic factors in patients with uncomplicated acute type B aortic dissection.

METHODS

From January 2003 to April 2012, a total of 228 patients with uncomplicated acute type B aortic dissection were admitted to our institute. Cox proportional hazards analysis was performed to identify risk factors for death, dissection-related death, and aortic events.

RESULTS

Independent predictors of mortality were age (hazard ratio [HR], 1.08; p < 0.001) and false lumen thickness (mm) (HR, 1.10; p = 0.013), and the risk factor for dissection-related death was false lumen thickness (mm) (HR, 1.14; p < 0.001). Independent risk factors for aortic events were diameter of the descending aorta (mm) (HR, 1.14; p < 0.001) and entry in a proximal site (HR, 2.90; p = 0.02). The actuarial freedom from aortic events in patients with a descending aortic diameter of less than 40 mm and no entry in a proximal site at 1, 3, and 5 years was 96.6%, 90.8%, and 82.5%, respectively, whereas in patients with 1 of these 2 factors, it was 80.1%, 66.8%, and 53.5%, respectively.

CONCLUSIONS

In uncomplicated acute type B aortic dissection, the diameter of the descending aorta and entry in a proximal site were independent prognostic factors for aortic events. Prophylactic TEVAR should be considered for patients with these risk factors.

Predictors of late aortic events after Stanford type B acute aortic dissection

OBJECTIVE

Patients with Stanford type B acute aortic dissection usually receive medical treatment during the acute phase. The present study aimed to elucidate the factors predicting late aortic events in patients treated conservatively for acute type B dissections.

METHODS

From March 1991 to March 2011, 117 patients were enrolled in the present study, with a mean follow-up period of 5.1 ± 4.1 years. The patients were divided into 4 groups according to their false lumen status at onset: group F, fully open (n = 26, 22.2%); group P, partially thrombosed (n = 23, 19.6%); group U, ulcer-like projections (n = 22, 18.9%); and group T, completely thrombosed (n = 46, 39.3%).

RESULTS

Long-term survival did not significantly differ among the groups. The Kaplan-Meier event-free rate curve showed that aortic events occurred less frequently in group T than in the other 3 groups; the 5-year event-free rate was 65.4%, 58.8%, 36.1%, and 95.7% for groups F, P, U, and T, respectively. Cox regression analysis showed that the presence of ulcer-like projections (P = .016) and a maximum aortic diameter of ≥ 40 mm (P = .003) were predictors of late aortic events.

CONCLUSIONS

When patients have a maximum aortic diameter of ≥40 mm or ulcer-like projections at onset, early surgical intervention should be considered to prevent positive remodeling of the aorta.