Endovascular stent-graft placement for the treatment of acute aortic dissection

Management of Renal Arteries in Conjunction with Thoracic Endovascular Aortic Repair for Complicated Stanford Type B Aortic Dissection: The Japanese Multicenter Study (J-Predictive Study)

Background Management of abdominal branches associated with Stanford type B aortic dissection is controversial without definite criteria for therapy after thoracic endovascular aortic repair (TEVAR). This is in part due to lack of data on natural history related to branch vessels and their relationship with the dissection flap, true lumen, and false lumen. Purpose To investigate the natural history of abdominal branches after TEVAR for type B aortic dissection and the relationship between renal artery anatomy and renal volume as a surrogate measure of perfusion. Materials and Methods This study included patients who underwent TEVAR for complicated type B dissection from January 2012 to March 2017 at 20 centers. Abdominal aortic branches were classified with following features: patency, branch vessel origin, and presence of extension of the aortic dissection into a branch (pattern 1, supplied by the true lumen without branch dissection; pattern 2, supplied by the true lumen with branch dissection, etc). The branch artery patterns before TEVAR were compared with those of the last follow-up CT (mean interval, 19.7 months) for spontaneous healing. Patients with one kidney supplied by pattern 1 and the other kidney by a different pattern were identified, and kidney volumes over the course were compared by using a simple linear regression model. Results Two hundred nine patients (mean age ± standard deviation, 66 years ± 13; 165 men and 44 women; median follow-up, 18 months) were included. Four hundred fifty-nine abdominal branches at the last follow-up were evaluable. Spontaneous healing of the dissected branch occurred in 63% (64 of 102) of pattern 2 branches. Regarding the other patterns, 6.5% (six of 93) of branches achieved spontaneous healing. In 79 patients, renal volumes decreased in kidneys with pattern 2 branches with more than 50% stenosis and branches supplied by the aortic false lumen (patterns 3 and 4) compared with contralateral kidneys supplied by pattern 1 (pattern 2 vs pattern 1: -16% ± 16 vs 0.10% ± 11, P = .002; patterns 3 and 4 vs pattern 1: -13% ± 14 vs 8.5% ± 14, P = .004). Conclusion Spontaneous healing occurs more frequently in dissected branches arising from the true lumen than in other branch patterns. Renal artery branches supplied by the aortic false lumen or a persistently dissected artery with greater than 50% stenosis are associated with significantly greater kidney volume loss. © RSNA, 2019 Online supplemental material is available for this article.

Endovascular Therapy for Nonischemic vs Ischemic Complicated Acute Type B Aortic Dissection

Purpose: To report a single-center experience with thoracic endovascular aortic repair (TEVAR) for complicated acute type B aortic dissection (cATBAD) comparing patients with vs without end-organ ischemia. Materials and Methods: Between November 2010 and December 2017, 64 patients (mean age 64.8±12.5 years; 49 men) underwent TEVAR for cATBAD. Patients were grouped into 2 cohorts: nonischemic (39, 61%) patients with unrelenting pain, early progressive aortic dilatation, uncontrolled hypertension, or rupture, and ischemic (25, 39%) patients with visceral, renal, lower extremity, or spinal cord hypoperfusion. Results: Mean time from diagnosis to treatment was 7.5 days (range 1–32) in the nonischemic group vs 2.3 days (range 1–14) days in the ischemic group (p=0.007). Fourteen (56%) of 25 ischemic cATBAD patients had stents implanted in the renovascular branch vessels, while 4 (16%) patients had stents implanted in the iliac arteries. When branch vessel cannulation failed, fenestrations were made in the intimal flap to improve perfusion of the involved branch (n=5). In the nonischemic group, 3 arteries were stented owing to atherosclerotic stenosis. Technical success was achieved in 62 (97%) of 64 patients; despite stenting, 2 patients had low renal artery perfusion on final angiography. There were no statistically significant differences in early or late outcomes between the nonischemic vs ischemic cATBAD patients. Six (9%) patients died within 30 days: 2 (5%) in the nonischemic group vs 4 (16%) in the ischemic group. Major complications (1 stroke, 2 cases of paraplegia, 1 retrograde type A dissection, and 1 case of bowel ischemia) occurred only in the nonischemic group. The mean follow-up was 28 months. Late endoleaks were observed in 3 (8%) nonischemic patients and 1 (4%) ischemic patient. Reinterventions were required in 7 (18%) nonischemic patients and 4 (16%) ischemic patients. Conclusion: TEVAR is an effective and safe method of treating cATBAD. Early intervention in ischemic cATBAD may have played a significant role in the lack of significant difference between ischemic and nonischemic cATBAD outcomes. Direct visceral reperfusion through branch vessel stenting during TEVAR may be crucial in achieving good outcomes in ischemic cATBAD.

Effects of circulating levels of Th17 cells on the outcomes of acute Stanford B aortic dissection patients after thoracic endovascular aortic repair: A 36-month follow-up study a cohort study

T helper 17 (Th17) cells are related to the progression of aortic dissection. This study aimed to determine whether circulating Th17 levels are associated with the prognosis of acute Stanford type B aortic dissection (STBAD) after thoracic endovascular aortic repair (TEVAR).A cohort study was performed and STBAD patients (n = 140) received TEVAR were enrolled, the circulating Th17 levels were measured and the patients were divided into low and high Th17 groups, and 36 months of follow-up was performed. The data for mortality, survival outcomes, heart structure and function changes, aortic regurgitation prevalence, and aortic remodeling outcomes were recorded.Lower mortality and fewer complications were observed in the low Th17 group than in the high Th17 group in the third year of follow-up. In addition, the low Th17 group exhibited better cardiac remodeling and cardiac function when compared with that in the high Th17 group in the second to third year after TEVAR. Aortic reflux was improved in both groups but was more pronounced in the low Th17 group. During follow-up, the true lumen of the proximal thoracic aorta at the level of the celiac trunk in both the low and high Th17 groups continuously enlarged and was more pronounced in the low Th17 group.Circulating Th17 cells were related to cardiac and aortic remodeling and prognosis during STBAD after TEVAR. Anti-inflammatory therapy may be useful for STBAD patients who have undergone TEVAR.

Combined proximal descending aortic endografting plus distal bare metal stenting (PETTICOAT technique) versus conventional proximal descending aortic stent graft repair for complicated type B aortic dissections

BACKGROUND

Aortic dissection is a separation of the aortic wall, caused by blood flowing through a tear in the inner layer of the aorta. Aortic dissection is an infrequent but life-threatening condition. The incidence of aortic dissection is 3 to 6 per 10,000 per year in the Western population, and can be up to 43 per 10,000 per year in the Eastern population. Over 20% of people with an aortic dissection do not reach a hospital alive. After admission, the mortality rates for people with an aortic dissection are between 10% and 20% for those who received endovascular treatment, and between 20% and 30% for those who had open surgery. Thoracic endovascular aortic repair (TEVAR) is the standard endovascular method to treat complicated type B aortic dissection (aortic dissections without involvement of the ascending aorta). Although TEVAR is less invasive than open surgery and has a better long-term aortic remodeling effect than conservative medical treatment, favourable aortic remodelling is usually limited to the thoracic aortic segment. TEVAR cannot be extended into the abdominal aorta because it could cover the ostia of the reno-visceral arteries. Thus, the abdominal aorta is still at risk of progressive aneurysmal degeneration. The PETTICOAT (provisional extension to induce complete attachment) technique, with proximal endograft and distal bare metal stent, was proposed in 2006 to address this issue. The concept of this technique was to implant a distal bare metal stent into the aortic true lumen, distal to the proximal endograft, to stabilize the distal collapsed intimal flap, while allowing blood flow to reno-visceral arteries. Therefore, the PETTICOAT technique was considered to be related to a more extensive aortic remodelling for people with type B aortic dissection, especially in the area of the abdominal aorta. However, it is still unclear whether the PETTICOAT technique is superior to standard TEVAR.

OBJECTIVES

To assess the effects of combined proximal descending aortic endografting plus distal bare metal stenting versus conventional proximal descending aortic stent graft repair for treating complicated type B aortic dissections.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases, and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 5 November 2018. We also undertook reference checking and citation searching to identify additional studies.

SELECTION CRITERIA

We considered all randomised controlled trials which compared the outcome of complicated type B aortic dissection, when treated by combined proximal descending aortic endografting plus distal bare metal stenting (PETTICOAT technique) versus conventional proximal descending aortic stent graft repair.

DATA COLLECTION AND ANALYSIS

Two independent review authors assessed all references identified by the Cochrane Vascular Information Specialist. We planned to undertake data collection and analysis in accordance with recommendations described in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We found no trials that met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

We identified no randomised controlled trials and therefore cannot draw any definite conclusion on this topic. Evidence from non-randomised studies appears to be favourable in the short-term, for combined proximal descending aortic endografting plus distal bare metal stenting (PETTICOAT technique) to solve the problem of unfavourable distal aortic remodeling. Randomised controlled trials are warranted to provide solid evidence on this topic. Evidence from cohort studies with large sample sizes would also be helpful in guiding clinical practice.

The use of non-contrast-enhanced MRI to evaluate serial changes in endoleaks after aortic stenting: a case report

Background

Aortic dissection is a life-threatening syndrome that sometimes requires emergency intervention, and endovascular aortic aneurysm repair (EVAR) is a treatment option. Long-term image follow-up is also required for patients after EVAR due to possible complications.

Case presentation

We present the case of a 73-year-old male with underlying chronic renal disease diagnosed with a type A aortic dissection who underwent EVAR. Four-dimensional (three spatial dimensions combined with time) phase-contrast magnetic resonance imaging (4D PC-MRI) was performed during regular follow-up in preference to contrast-enhanced computed tomography or simple MRI while taking his poor renal function into consideration.

Conclusions

We considered this preferable given his issues with renal function.

Two Cases of Endovascular Repair with the Stent Graft for Retrograde Type A Acute Aortic Dissection with Complications

Thoracic endovascular aortic repair (TEVAR) is used to treat retrograde type A acute aortic dissection (RTAAD). In case 1, a 52-year-old man, who was conservatively managed, reported worsening back pain. Emergency TEVAR was performed 7 days after onset. After deploying two GORE Conformable TAG (CTAG) in the descending aorta, his symptoms disappeared. In case 2, a 52-year-old man with progressive worsening resistant hypertension, renal dysfunction, and respiratory failure despite maximal medical therapy underwent TEVAR 8 days after onset. A CTAG was deployed from the left subclavian artery under rapid pacing, and two Zenith Dissection stents were placed, which resolved complications. In both cases, after 6 months, computed tomography (CT) scan showed complete resorption of the false lumen in the ascending aorta. TEVAR for RTAAD with complete thrombosis of false lumen in the ascending aorta can be an alternative to surgery when the primary tear is located in descending aorta.

Fusion Imaging to Guide Thoracic Endovascular Aortic Repair (TEVAR): A Randomized Comparison of Two Methods, 2D/3D Versus 3D/3D Image Fusion

PURPOSE

To compare the accuracy of two-dimensional (2D) versus three-dimensional (3D) image fusion for thoracic endovascular aortic repair (TEVAR) image guidance.

MATERIALS AND METHODS

Between December 2016 and March 2018, all eligible patients who underwent TEVAR were prospectively included in a single-center study. Image fusion methods (2D/3D or 3D/3D) were randomly assigned to guide each TEVAR and compared in terms of accuracy, dose area product (DAP), volume of contrast medium injected, fluoroscopy time and procedure time.

RESULTS

Thirty-two patients were prospectively included; 18 underwent 2D/3D and 14 underwent 3D/3D TEVAR. The 3D/3D method allowed more accurate positioning of the aortic mask on top of the fluoroscopic images (proximal landing zone error vector: 1.7 ± 3.3 mm) than was achieved by the 2D/3D method (6.1 ± 6.1 mm; p = 0.03). The 3D/3D image fusion method was associated with significantly lower DAP than the 2D/3D method (50.5 ± 30.1 Gy cm² for 3D/3D vs. 99.5 ± 79.1 Gy cm² for 2D/3D; p = 0.03). The volume of contrast medium injected was significantly lower for the 3D/3D method than for the 2D/3D method (50.6 ± 22.9 ml vs. 98.4 ± 47.9 ml; p = 0.002).

CONCLUSION

Higher image fusion accuracy and lower contrast volume and irradiation dose were observed for 3D/3D image fusion than for 2D/3D during TEVAR.

LEVEL OF EVIDENCE

II, Randomized trial.

Predictor of false lumen thrombosis after thoracic endovascular aortic repair for type B dissection

OBJECTIVE

Thoracic endovascular aortic repair of type B aortic dissection initiates thrombosis in the false lumen, which eventually results in aortic remodeling. We aimed to determine whether the false lumen thrombosis rate (FLTR) after thoracic endovascular aortic repair can be accurately predicted by an index that expresses the degree of aortic arch angulation.

METHODS

The geometry of 48 patients with acute type B aortic dissection (mean age, 48 years) after thoracic endovascular aortic repair was reconstructed from postoperative computed tomography images. We introduced a novel angle-the degree of question mark (φ)-to indicate the aortic morphology. Moreover, how aortic angulation influenced the FLTR was investigated based on hemodynamic parameters. Finally, a predicted mathematical model relating FLTR to aortic angulation was proposed, and 10 patients were chosen to validate the model.

RESULTS

The degree of question mark shape was shown to negatively correlate with FLTR (n = 38; P < .001; R = -0.661), and the linear relationship model was created as follows: FLTR (%) = -1.955 × φ + 168.24 (R² = 0.437; P < .001). In addition, the net flow rate to the false lumen significantly increased with the increase of the degree of the question mark shape of the aorta. Furthermore, the difference and concordance of the proposed prediction model were perfectly validated in the remaining 10 patients using paired-sample t test and the concordance correlation coefficient.

CONCLUSIONS

The size of the question mark shape may be a good predictor for FLTR of acute type B aortic dissection following thoracic endovascular aortic repair. The higher the degrees of the question mark, the less likely it was to form a complete thrombus.

Development of a shear-thinning biomaterial as an endovascular embolic agent for the treatment of type B aortic dissection

False lumen embolisation is a promising treatment strategy in type B aortic dissection (TBAD) but it is limited by the lack of a disease-specific embolic agent. Our aim was to develop a biomaterial that could be delivered minimally-invasively into the TBAD false lumen and embolise the region. We created 24 shear-thinning biomaterials from blends of gelatin, silicate nanoparticles and silk fibroin, and evaluated their suitability as a false lumen embolic agent in TBAD. We determined the stability of mechanical properties by measuring the compressive modulus of samples stored in physiological conditions over a 21 day period. We quantified injectability by measuring the force required to inject each biomaterial through catheters of varying diameter. We also assessed in vitro degradation rates by measuring weight change over 30 days. Finally, we developed an in vitro experimental pulsatile flow setup with two different anatomically-correct TBAD geometries and performed 78 false lumen occlusion experiments under different operating conditions. We found that the compressive moduli changed rapidly on exposure to 37 °C before stabilising by Day 7. A high silicate nanoparticle to gelatin ratio resulted in greater compressive moduli, with a maximum of 117.6 ± 15.2 kPa. By reducing the total solid concentration, we could improve injectability and biomaterials with 8% (w/v) solids required <80 N force to be injected through a 4.0 mm catheter. Our in vitro degradation rates showed that the biomaterial only degraded by 1.5-8.4% over a 30 day period. We found that the biomaterial could occlude flow to the false lumen in 99% of experiments. In conclusion, blends with high silicate nanoparticle and low silk fibroin content warrant further investigation for their potential as false lumen embolic agents and could be a promising alternative to current TBAD repair methods.

Thoracic endovascular aortic repair with stent grafts alone or with a composite device design in patients with acute type B aortic dissection in the setting of malperfusion

OBJECTIVE

The objective of this study was to compare short-term outcomes in patients who underwent thoracic endovascular aortic repair (TEVAR) with stent grafts alone or with a composite device design (stent graft plus bare-metal aortic stent) for acute type B aortic dissection in the setting of malperfusion.

METHODS

This retrospective analysis included patients with acute (≤14 days of symptom onset) complicated type B dissection in the setting of malperfusion who were treated with stent grafts alone (TEVAR cohort) at two European institutions vs those who underwent TEVAR with a composite device design (Cook Medical, Bloomington, Ind) in the investigational STABLE I feasibility study and STABLE II pivotal study (STABLE cohort). Preoperative characteristics and 30-day outcomes (including mortality, malperfusion-related mortality, morbidity, and secondary interventions) were compared between the two groups.

RESULTS

The TEVAR cohort (41 patients; mean age, 58.8 ± 12.7 years; 78.0% male) and the STABLE cohort (84 patients; mean age, 57.8 ± 11.7 years; 71.4% male) were largely similar in preoperative medical characteristics, with more STABLE patients presenting with a history of hypertension (79.8% vs 58.5%; P = .018). The TEVAR and STABLE groups had similar lengths of dissection (451.8 ± 112.7 mm vs 411.8 ± 116.4 mm; P = .10) and similar proximal and distal extent of dissection. At presentation, the two groups exhibited comparable organ system involvement in malperfusion: renal (53.7% TEVAR, 57.1% STABLE), gastrointestinal (41.5% TEVAR, 44.0% STABLE), lower extremities (34.1% TEVAR, 52.4% STABLE), and spinal cord (9.8% TEVAR, 2.4% STABLE). The 30-day rate of all-cause mortality was 17.1% (7/41) in the TEVAR group and 8.3% (7/84) in the STABLE group (P = .22). The 30-day rate of malperfusion-related mortality (deaths from bowel/mesenteric ischemia or multiple organ failure) was 12% (5/41) in the TEVAR group and 2.4% (2/84) in the STABLE group (P = .038). The 30-day morbidity, for the TEVAR and STABLE groups, respectively, included bowel ischemia (9.8% [4/41] vs 2.4% [2/84]; P = .09), renal failure requiring dialysis (7.3% [3/41] vs 9.5% [8/84]; P > .99), paraplegia or paraparesis (4.9% [2/41] vs 3.6% [3/84]; P = .66), and stroke (2.4% [1/41] vs 10.7% [9/84]; P = .16). The occurrence of 30-day secondary intervention was similar in the TEVAR and STABLE groups (7.3% [3/41] vs 7.1% [6/84]; P > .99). True lumen expansion in the abdominal aorta was significantly greater in the STABLE group.

CONCLUSIONS

In patients with acute type B aortic dissection in the setting of branch vessel malperfusion, the use of a composite device with proximal stent grafts and distal bare aortic stent appeared to result in lower malperfusion-related mortality than the use of stent grafts alone. The 30-day rates of morbidity and secondary interventions were similar between the groups.

One-stage aortic replacement for type A aortic dissection: using a Vasoring and a conventional elephant trunk graft

OBJECTIVES

We used a vascular ring connector (Vasoring) and a conventional elephant trunk graft for complete repair in open surgery for type A aortic dissection. This report described the immediate and mid-term results of this new technique.

METHODS

We used a rigid titanic ring as a stent in the vascular graft for rapid sutureless anastomosis in the reconstruction of type A aortic dissection.

RESULTS

A total of 65 consecutive patients with Stanford type A aortic dissection underwent open surgery performed by a single surgeon from November 2007 to February 2017. All patients underwent aortic reconstruction with vascular grafts and Vasorings (21 patients in the ascending aorta and 44 patients in the total aortic arch). For total aortic arch replacement, we implanted the conventional vascular graft in the proximal descending thoracic aorta as an elephant trunk graft. Concomitant procedures included the Bentall procedure (9 patients), the David operation (6 patients), coronary artery bypass grafting (9 patients), heart transplantation (1 patient), mitral valve replacement (2 patients) and endovascular aortic repair (1 patient). The mean duration of postoperative endotracheal intubation was 17.0 ± 11.8 h. The average blood loss was 520 ± 743 ml, and 25% of patients required no blood transfusion. The in-hospital mortality rate was 6%.

CONCLUSIONS

The combined use of the vascular ring connector and the conventional elephant trunk graft may reduce bleeding and pump time, stop the blood flow in the false lumen and allow the 1-stage total arch replacement to be performed safely. The conventional elephant trunk graft is free from stent graft-induced new entry.

Endovascular treatment of complex diseases of the thoracic aorta-10 years single centre experience

BACKGROUND

Introduction of invasive endovascular techniques constituted a real a breakthrough in the treatment of aortic aneurysm dissection and rupture. We assessed the effectiveness and safety of thoracic endovascular aortic repair (TEVAR) in patients with thoracic aortic pathologies.

METHODS

Between 2007 and 2017, 118 patients with thoracic aortic pathology underwent TEVAR. Among them, 20 (16.9%) patients required hybrid procedures. Stent grafts indication were thoracic aortic aneurysm in 46 (39.0%) patients, type B dissection in 68 (57.6%) patients and other indications in 4 (3.3%). Procedural success rate, in-hospital and late mortality and morbidity were evaluated.

RESULTS

The patients were followed-up for a mean of 55 months (range, 6-118 months). The technical success rate was 96%. Five patients died during the first 30 days after procedure (mortality 4.2%), four due to ischemic stroke followed by multi-organ failure and another one hemodynamically significant type I endoleak. Most of them were noted in the first years of our study. Five others died during post-discharged period. Four patients developed neurological complications, including stroke (n=2; 1.7%) and paraparesis (n=2; 1.7%). There were 6 (5.1%) primary (5 type I and 1 type II) and 3 (2.5%) secondary endoleaks (1 type I and 2 type III). Secondary interventions were required in 8 subjects. There was one case of stent collapse and two retrograde aortic dissection.

CONCLUSIONS

Treatment of descending aortic diseases by using stent graft implantation has become the method of choice, decreasing the risk of open surgery, especially in patients with severe clinical state and comorbidities. However, effectiveness and safety may be achieved by experience team.

Optimal blood pressure control for patients after thoracic endovascular aortic repair of type B aortic dissection

BACKGROUND

Guidelines recommend tight systolic blood pressure (SBP) control for favorable outcomes of type B aortic dissection (BAD) but are still limited by the optimal cut-off value of SBP. The purpose of this study was to evaluate the optimal cut-off value of SBP in BAD patients after thoracic endovascular aortic repair (TEVAR).

METHODS

From January 2011 to April 2017, 269 consecutive patients with BAD after TEVAR were included in the study. All patients were followed up according to a strict follow-up protocol. Cox regression analysis was used to examine the association between SBP at discharge and 90-day aortic related adverse events (ARAE).

RESULTS

All 269 patients completed 90 days of follow-up, and the unadjusted ARAE-free rates at 90-day was 95.1 ± 1.3%. The cut-off value of SBP at discharge identified by receiver operator curve was 130 mmHg for 90-day ARAE. In multivariable models, binary SBP at discharge was significant associated with 90-day ARAE (HR 3.780; 95% CI 1.236-11.556; p = 0.020). Hybrid operation (OR 2.046; 95%CI 1.015-4.122; p = 0.045) and insertion of ≥2 stents (OR 2.950; 95%CI 1.172-7.426; p = 0.022) were demonstrated to be independently associated with poor SBP control (SBP > 130 mmHg) using Logistic analysis.

CONCLUSIONS

The optimal cut-off value of SBP at discharge was 130 mmHg which can be used to predict short-term ARAE. Blood pressure in patients with hybrid operation and ≥ 2 stents should be given more focus.

Type 2 diabetes mellitus reduces clinical complications and mortality in Stanford type B aortic dissection after thoracic endovascular aortic repair: A 3-year follow-up study

BACKGROUND

Previous studies have demonstrated that type 2 diabetes mellitus (T2DM) is negatively correlated with the occurrence of aortic dissection (AD). This study aimed to investigate the effects of T2DM on the prognosis of Stanford type B AD (STBAD) patients after thoracic endovascular aortic repair (TEVAR).

METHODS

STBAD patients (n = 141) who underwent TEVAR received an oral glucose tolerance test (OGTT) and were divided into a normal glucose (NG, n = 55) group, an abnormal glucose tolerance (AGT, n = 48) group and a T2DM (n = 38) group according to the results of the OGTT. Data on mortality, clinical complications, left ventricular (LV) remodeling and aortic remodeling were collected during the 3-year follow-up.

RESULTS

Lower mortality and fewer clinical complications after TEVAR were found in the T2DM group than in the NG group. Multivariate linear regression analysis showed that 2-hour postprandial glucose (Glu-2h) was negatively correlated with mortality and the occurrence of clinical complications in STBAD patients after TEVAR. In addition, better LV remodeling, larger true lumen areas and smaller false lumen areas in both the proximal aortas and abdominal aortas were observed in the T2DM group than in the NG group. Furthermore, no significant differences in mortality or clinical complications after TEVAR were found between the NG group and the AGT group or between the T2DM group and the AGT group.

CONCLUSION

During the 3-year follow-up period, mortality and clinical complications in STBAD patients after TEVAR were significantly reduced in the T2DM group. For STBAD patients who undergo TEVAR, properly relaxing of blood glucose control requirements may be beneficial for their prognosis.

The Year in Vascular Anesthesia: Selected Highlights From 2018

This special article is the second in an annual series for the Journal of Cardiothoracic and Vascular Anesthesia that is specifically dedicated to highlights in vascular anesthesiology published in 2018. This review begins with 2 updates in preoperative medicine in the vascular surgery population, including recent publications regarding the management of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers and antiplatelet medications in the perioperative period. The next section focuses on complications related to thoracic endovascular aortic surgery, particularly as technology advances allow for endovascular repair of more complex anatomy. The final section focuses on quality in vascular surgery and evaluates recent publications that examine the safety and feasibility of fast-track endovascular aortic surgery. Even though this is only a sampling of the literature published in 2018 relevant to the cardiovascular anesthesiologist, these themes represent some of the topics most clinically relevant to the perioperative period.

Renal Stent Migration Following TEVAR for Complicated Type B Aortic Dissection

We describe renal stent migration following thoracic endovascular aortic repair (TEVAR) for type B aortic dissection. A 68-year-old male presented with type B aortic dissection. His course was complicated by renal and lower extremity malperfusion. Thoracic endovascular aortic repair was performed and completion angiogram showed no flow in the left renal artery. A renal stent was deployed with the proximal margin of the stent 1 mm into the aortic true lumen, providing improved renal perfusion. One week after TEVAR, contrast-enhanced computed tomography (CT) revealed that the renal stent had embolized to the aortic bifurcation. Additional endovascular therapy successfully crushed the renal stent against the iliac artery wall utilizing a larger bare metal stent. At 3 year follow-up, contrast-enhanced CT demonstrated good patency of the left renal artery and right iliac artery. This complication alerts physicians to consider subsequent aortic remodeling during endovascular intervention for acute aortic dissection with malperfusion.

Acute Type B Dissection

Aortic dissections are catastrophic vascular emergencies, and early recognition and appropriate interventions can be crucial to survival. Research has changed the way aortic dissections are managed over the past two decades and will continue to contribute to the evolution of treatment modalities. Early treatment for uncomplicated type B dissections still remains controversial but certain characteristics may benefit from early intervention.

Outcomes and Predictors of Endovascular Treatment for Type B Aortic Dissection Complicated by Unilateral Renal Ischemia

PURPOSE

This study investigated the outcomes of endovascular treatment for type B aortic dissection (TBAD) complicated by unilateral renal ischemia and determined the associated predictors.

MATERIALS AND METHODS

From January 2010 to December 2016, 44 patients (mean : 54 years of age) with TBAD complicated by a clearly involved unilateral renal artery and a decreased mean density of the unilateral renal parenchyma were enrolled. The volumes and mean densities of each kidney were generated with postprocessing software based on computed tomography angiography. The degree of renal malperfusion (RMD) was defined as the bilateral density difference-to-the mean density ratio of the healthy kidney. The primary outcomes were renal atrophy and renal dysfunction; the secondary outcomes were aorta-related complications.

RESULTS

The median follow-up time was 51 months (range: 12-102 months). During follow-up, unilateral renal atrophy and renal dysfunction were observed in 12 patients (27.3%) and 7 patients (15.9%), respectively. RMD showed a moderate predictive value for renal atrophy, with an area under the characteristic curve (AUC) of 0.78. The optimal cutoff value was 27% for RMD in terms of predicting renal atrophy (sensitivity: 91.7%; specificity: 56.2%). Moreover, aorta-related adverse events occurred in 14 patients (31.8%). Preoperative abnormal creatinine level was an independent risk factor for aorta-related complications (odds ratio [OR]: 17.5; P = 0.022) and renal dysfunction (OR: 14.2; P = 0.02).

CONCLUSIONS

Preoperative serum creatinine was an effective index used to predict renal and aortic outcomes in this patient cohort. Active imaging follow-up and aggressive endovascular intervention are suggested in patients with RMD >27%.

Successful Endovascular Therapy for Isolated Abdominal Aortic Dissection Involving Bilateral Common Iliac Arteries

A 69-year-old male patient was admitted to our hospital due to sudden right leg pain and paralysis when walking, which was suspected to be acute limb ischemia. Computed tomography and aortography revealed isolated abdominal aortic dissection with bilateral common iliac artery (CIA) stenosis. Endovascular therapy was performed. A Palmaz XL stent (20×40 mm) was deployed on the aortic dissection with intravascular ultrasound assistance. Subsequently, CIA lesions disappeared. Stent deployment at the aortic dissection primary tear resulted in occlusion of the false lumen of the distal dissection of the bilateral CIAs. Postoperatively, his symptoms disappeared, with no recurrence during 14 months of follow-up.

False lumen embolization in chronic aortic dissection promotes thoracic aortic remodeling at midterm follow-up

OBJECTIVE

Failure of thoracic endovascular aortic repair (TEVAR) in chronic aortic dissections can be partially explained by retrograde false lumen (FL) flow through distal re-entry tears. After implantation of a thoracic stent graft, FL thrombosis occurs in less than 50% of the cases. The objectives of this study were to describe the feasibility and outcomes of FL embolization in patients with chronic aortic dissections.

METHODS

Between June 2015 and January 2018, 27 patients (mean age, 61 ± 14 years) with chronic aortic dissection underwent FL embolization as an adjunct during or after TEVAR placement procedure. Indications for embolization were (1) symptomatic chronic aortic dissections with pain or rapid growth of aortic diameter (≥5 mm/y) requiring rapid exclusion of the aneurysm, (2) aneurysmal dilatation with persistent FL retrograde flow after TEVAR, and (3) large FL aneurysms (≥55 mm) that might lead to persistent retrograde flow. Twenty patients presented with type B chronic aortic dissections (74.1%) and seven presented a residual type A chronic aortic dissections (25.9%). Eight patients had a previous aortic arch replacement (29.6%). Six patients had previous repair with TEVAR (22.2%). The delay between the onset of dissection and the first endovascular repair was 47 months (range, 3-144). Spinal fluid drainage was used in 74.1% of cases (20/27 patients). Embolization devices included coils and vascular plugs.

RESULTS

The technical success rate was 100% (27/27). Complete spinal cord ischemia was observed in one patient (3.7%). There was one hospital death from pneumonia after zone 1 supra-aortic trunk debranching with TEVAR and embolization. After the index procedure, FL thrombosis was observed in 81.5% of patients (22/27) on late phase computed tomography angiography. Five patients required two or more embolization procedures, leading to a high rate of complete FL thrombosis (92.6%). One patient presented a type IB endoleak and one patient presented a type II endoleak. Radiologic follow-up was 20 ± 10 months. The maximum thoracic aortic diameter significantly decreased from 63 mm to 54 ± 10 mm (P < .001).

CONCLUSIONS

Embolization of the FL of chronic aortic dissections is technically feasible with a low morbidity rate. The FL thrombosis is observed in the majority of case and promotes favorable thoracic aortic remodeling. Longer follow-up is needed to confirm these good results on the thoracic aorta and this technique may, therefore, improve the results of TEVAR in chronic aortic dissections.

Cocaine use is associated with worse outcomes in patients treated with thoracic endovascular repair for type B aortic dissection

OBJECTIVE

To describe and compare the clinical and anatomical characteristics and outcomes of patients with and without known cocaine use who underwent thoracic endovascular repair for type B aortic dissections.

METHODS

Between January 2012 and January 2017, 186 patients underwent thoracic endovascular repair for type B aortic dissection at our institution. Clinical data and anatomical characteristics were collected under an institutional review board-approved protocol. Survival, reintervention, complications, and characteristics of dissection were compared between patients with cocaine use (C+; n = 14) and those with no known cocaine use (C-; n = 172).

RESULTS

Cocaine users were more likely to be young African American males who smoked. They tended to present with more extensive dissections as evidenced by larger false lumen diameters. They also had higher rates of endoleaks and more reinterventions.

CONCLUSIONS

These results suggest that special care should be taken to provide close follow-up for these patients.

A graft inversion technique for retrograde type A aortic dissection after thoracic endovascular repair for type B aortic dissection

Background

Retrograde type A aortic dissection (RTAD) is a rare but life-threatening complication after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD). A graft inversion technique was applied to distal anastomosis in total arch replacement for this complicated dissection. We reviewed our results of the processing for this serious complication. The aim is to evaluate the feasibility of this technology.

Methods

From January 2013 to December 2017, 20 patients (80% male, mean age 50.9 ± 9.5 years) with retrograde type A aortic dissection after thoracic endovascular aortic repair for type B aortic dissection were scheduled for surgical treatment at our center. All patients underwent an ascending aorta and total aortic arch replacement procedure. The 20 patients were divided into two groups, 1 group involved 9 patients underwent surgery using stepwise technique; the graft inversion technique was performed in the other group containing the remaining 11 patients. The postoperative variables, including cardiopulmonary bypass time, the circulatory arrest time, the aortic cross clamp time, were analyzed. Meanwhile we also analyzed the postoperative mortality and complications to evaluate the early and mid-term outcomes of surgical treatment for RTAD after TEVAR.

Results

In-hospital mortality was 10% (2 of 20 patients). No patient developed postoperative paraplegia, renal failure, stroke, or distal anastomotic bleeding. Two patients developed renal insufficiency, one developed neurologic insufficiency, and one developed pulmonary infection, all of which were managed accordingly. Cardiopulmonary bypass (CPB) time, and circulatory arrest time were significantly shorter in the graft inversion group than in the stepwise group (165.8 ± 37.9 min versus 206.1 ± 46.8 min, p<0.05; 34.5 ± 5.6 min versus 42.4 ± 9.5 min, p<0.05, respectively). The 18 survivors had a mean follow-up of 25.8 ± 18.2 months, and all patients remained alive and well.

Conclusion

Graft inversion can enable a secure distal anastomosis under good surgical exposure, resulting in reduced durations of CPB, and circulatory arrest for RTAD after TEVAR. Surgical treatment could be a safe alternative for treatment of this patients.

Electronic supplementary material

The online version of this article (10.1186/s13019-019-0851-9) contains supplementary material, which is available to authorized users.

Anaesthetic Management of Planned or Emergency Endovascular Stent Graft Surgery for Thoracic Aneurysms and Dissections

We reviewed the intraoperative anaesthetic management and outcome of seven consecutive cases of endovascular stent graft surgery for thoracic aortic aneurysms or dissections over a period of 20 months in our institution. Seven males (median age 63) underwent endovascular stent graft surgery of the thoracic aorta under general anaesthesia. Four were emergency procedures for acute dissection or leaks of thoracic aneurysms. The duration of the procedures ranged from 120 to 300 minutes. Intraoperative stent migration occurred in one patient. Induced hypotension and immobilization were critical during stent deployment. Six out of the seven patients were discharged home between three to 20 days postoperatively. There was no 30-day mortality. One patient died sixty days postoperatively. Anaemia and respiratory complications were the most common postoperative problems encountered. None of the patients sustained spinal cord ischaemia, acute myocardial infarction or renal impairment. Endovascular stent graft surgery of the thoracic aorta is a relatively new alternative to conventional open surgery. Our experience suggests satisfactory short-term outcome even for patients with acute dissection. However, long-term survival and results require further evaluation.

Implications of secondary aortic intervention after thoracic endovascular aortic repair for acute and chronic type B dissection

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) has become a mainstay of therapy for acute and chronic type B aortic dissection (TBAD). Dynamic aortic morphologic changes, untreated dissected aorta, and persistent false lumen perfusion have significant consequences for reintervention after TEVAR for TBAD. However, few reports contrast differences in secondary aortic intervention (SAI) after TEVAR for TBAD or describe their influence on mortality. This analysis examined incidence, timing, and types of SAI after TEVAR for acute and chronic TBAD and determined their impact on survival.

METHODS

All TEVAR procedures for acute and chronic TBAD (2005-2016) were retrospectively reviewed. Patients with staged (<30 days) or concomitant ascending aortic arch repair or replacement were excluded. Acuity was defined by symptom onset (0-30 days, acute; >30 days, chronic). SAI procedures were grouped into open (intended treatment zone or remote aortic site), major endovascular (TEVAR extension or endograft implanted at noncontiguous site), and minor endovascular (side branch or false lumen embolization) categories. Kaplan-Meier methodology was used to estimate freedom from SAI and survival. Cox proportional hazards were used to identify SAI predictors.

RESULTS

TEVAR for TBAD was performed in 258 patients (acute, 49% [n = 128]; chronic, 51% [n = 130]). Mean follow-up was 17 ± 22 months with an overall SAI rate of 27% (n = 70; acute, 22% [28]; chronic, 32% [42]; odds ratio, 1.7; 95% confidence interval, 0.9-2.9; P = .07]. Median time to SAI was significantly less after acute than after chronic dissection (0.7 [0-12] vs 7 [0-91] months; P < .001); however, freedom from SAI was not different (1-year: acute, 67% ± 4%, vs chronic, 68% ± 5%; 3-year: acute, 65% ± 7%, vs chronic, 52% ± 8%; P = .7). Types of SAI were similar (acute vs chronic: open, 61% vs 55% [P = .6]; major endovascular, 36% vs 38% [P = .8]; minor endovascular, 21% vs 21% [P = 1]). The open conversion rate (either partial or total endograft explantation: acute, 10% [13/128]; chronic, 15% [20/130]; P = .2) and incidence of retrograde dissection (acute, 6% [7/128]; chronic, 4% [5/130]; P = .5) were similar. There was no difference in survival for SAI patients (5-year: acute + SAI, 55% ± 9%, vs acute without SAI, 67% ± 8% [P = .3]; 5-year: chronic + SAI, 72% ± 6%, vs chronic without SAI, 72% ± 7% [P = .7]). Factors associated with SAI included younger age, acute dissection with larger maximal aortic diameter at presentation, Marfan syndrome, and use of arch vessel adjunctive procedures with the index TEVAR. Indication for the index TEVAR (aneurysm, malperfusion, rupture, and pain or hypertension) or remote preoperative history of proximal arch procedure was not predictive of SAI.

CONCLUSIONS

SAI after TEVAR for TBAD is common. Acute TBAD has a higher proportion of early SAI; however, chronic TBAD appears to have ongoing risk of remediation after the first postoperative year. SAI types are similar between groups, and the occurrence of aorta-related reintervention does not affect survival. Patients' features and anatomy predict need for SAI. These data should be taken into consideration for selection of patients, device design, and surveillance strategies after TEVAR for TBAD.

Aortic remodeling in Type B aortic dissection after thoracic endovascular aortic repair with an aortic extender cuff implantation

Objective

This study investigated the safety and efficiency of thoracic endovascular aortic repair (TEVAR) plus an aortic extender cuff placement in treating Stanford Type B aortic dissections (TBADs).

Methods

Clinical data on 157 patients with TBADs who underwent TEVAR in two tertiary medical centers from February 2013 to March 2018 were analyzed retrospectively. An estimated mismatch rate >120% was the indication for placement of an aortic extender cuff. Results in the perioperative and follow-up periods (≥3 months) were analyzed, especially those of aortic remodeling.

Results

In total, 106 patients (67.5%) underwent standard TEVAR, and 51 (32.5%) received TEVAR plus an aortic extender cuff placement. The primary technical success rate was 96.8% (152/157). Perioperative adverse events included endoleak (2%, 3/157), spinal cord ischemia (SCI) (1.3%, 2/157), and transient renal failure (0.6%, 1/157), with no between-group differences. The median follow-up was 15 months (range 3–71 months). Ten cases of late stent complications were observed, including three endoleak, one upper limb ischemia, one stent distortion, and five stent graft-induced distal re-dissection (SIDR). Patients with a cuff had less distal re-dissection and fewer second interventions, but the differences lacked significance. In the last follow-up, the TEVAR+Cuff group were found to have better true lumen recovery and false lumen shrinkage, and increased complete false lumen thrombosis in the thoracic and abdominal segments; however, no statistical difference was evident in comparison with the TEVAR group (P>0.05).

Conclusion

TEVAR plus an aortic extender cuff implantation improves remodeling of the dissected thoracic aorta, thus reducing the potential of SIDR. Furthermore, the covered stent with a length of 250 mm does not increase the rate of SCI or paraplegia. However, these results should be confirmed in a larger series of patients with longer follow-up.

Aortoesophageal Fistula: A Fatal Complication of Thoracic Endovascular Aortic Stent-Graft Placement

Patient: Female, 80

Final Diagnosis: Aortoesophageal fistula

Symptoms: Hematemesis

Medication: —

Clinical Procedure: Thoracic endovascular aortic repair

Specialty: General and Internal Medicine

Mechanical stretch aggravates aortic dissection by regulating MAPK pathway and the expression of MMP-9 and inflammation factors

This study aimed to explore whether mechanical stretch aggravated aortic dissection through regulating MAPK pathway, MMP-9, and inflammation factors. We first established aortic dissection model rats. Mechanical stretch (3 g) was exerted on vascular ring of aortic dissection which was also treated by inhibitors of MAPK pathway (SB203580, SP600125, and U0126). HE and Masson staining showed that aortic dissection severity with 3 g tension was worse than that without tension (0 g); after the treatments of diverse inhibitors, the fracture and breakage of the elastic fibers decreased. The expression of MMP-9, TNF-α, IL-1β) p38/p-p38, JNK1/p-JNK1, and ERK1/2/p-ERK1/2 were determined by immunohistochemical analysis, RT-PCR, and western blot. No matter whether tension was exerted or inhibitors were added, there was no change in the expression of p38, JNK1, and ERK1/2. However, compared to the 0 g group, the expression of MMP-9, TNF-α, IL-1β, p-p38, p-JNK1, and p-ERK1/2 was significantly upregulated in the 3 g group (P < 0.05). In both 0 g and 3 g groups, the expression of MMP-9, TNF-α, IL-1β, p-p38, p-JNK1, and p-ERK1/2 was remarkably downregulated after inhibitors treatment (P < 0.05). In conclusion, mechanical stretch aggravated aortic dissection by regulating the MAPK pathway and the consequent expression of MMP-9 and inflammation factors.

Hybrid treatment of type B aortic dissection with retrograde extension in a patient with anomalous aortic arch

Hybrid treatment of aortic arch encompasses a combination of endovascular stenting with surgical revascularization of supraaortic branches. Herein, we report a 53-year-old male case of type B aortic dissection with retrograde extension and anomalous aortic arch. The patient was successfully treated by hybrid treatment using bilateral carotico-subclavian bypass grafting and endovascular stent grafting.

Multilayer flow modulator enhances vital organ perfusion in patients with type B aortic dissection

Management of aortic dissections (AD) is still challenging, with no universally approved guideline among possible surgical, endovascular, or medical therapies. Approximately 25% of patients with AD suffer postintervention malperfusion syndrome or hemodynamic instability, with the risk of sudden death if left untreated. Part of the issue is that vascular implants may themselves induce flow disturbances that critically impact vital organs. A multilayer mesh construct might obviate the induced flow disturbances, and it is this concept we investigated. We used preintervention and post-multilayer flow modulator implantation (PM) geometries from clinical cases of type B AD. In-house semiautomatic segmentation routines were applied to computed tomography images to reconstruct the lumen. The device was numerically reconstructed and adapted to the PM geometry concentrically fit to the true lumen centerline. We also numerically designed a pseudohealthy case, where the geometry of the aorta was extracted interpolating geometric features of preintervention, postimplantation, and published representative healthy volunteers. Computational fluid dynamics methods were used to study the time-dependent flow patterns, shear stress metrics, and perfusion to vital organs. A three-element Windkessel lumped parameter module was coupled to a finite-volume solver to assign dynamic outlet boundary conditions. Multilayer flow modulator not only significantly reduced false lumen blood flow, eliminated local flow disturbances, and globally regulated wall shear stress distribution but also maintained physiological perfusion to peripheral vital organs. We propose further investigation to focus the management of AD on both modulation of blood flow and restoration of physiologic end-organ perfusion rather than mere restoration of vascular lamina morphology. NEW & NOTEWORTHY The majority of aortic dissection modeling efforts have focused on the maintenance of physiological flow using minimally invasive placed grafts. The multilayer flow modulator is a complex mesh construct of wires, designed to eliminate flow disruptions in the lumen, regulate the physiological wall stresses, and enhance endothelial function and offering the promise of improved perfusion of vital organs. This has never been fully proved or modeled, and these issues we confirmed using a dynamic framework of time-varying arterial waveforms.

Computational Fluid Dynamic Accuracy in Mimicking Changes in Blood Hemodynamics in Patients with Acute Type IIIb Aortic Dissection Treated with TEVAR

Background: We aimed to verify the accuracy of the Computational Fluid Dynamics (CFD) algorithm for blood flow reconstruction for type IIIb aortic dissection (TBAD) before and after thoracic endovascular aortic repair (TEVAR). Methods: We made 3D models of the aorta and its branches using pre- and post-operative CT data from five patients treated for TBAD. The CFD technique was used to quantify the displacement forces acting on the aortic wall in the areas of endograft, mass flow rate/velocity and wall shear stress (WSS). Calculated results were verified with ultrasonography (USG-Doppler) data. Results: CFD results indicated that the TEVAR procedure caused a 7-fold improvement in overall blood flow through the aorta (p = 0.0001), which is in line with USG-Doppler data. A comparison of CFD results and USG-Doppler data indicated no significant change in blood flow through the analysed arteries. CFD also showed a significant increase in flow rate for thoracic trunk and renal arteries, which was in accordance with USG-Doppler data (accuracy 90% and 99.9%). Moreover, we observed a significant decrease in WSS values within the whole aorta after TEVAR compared to pre-TEVAR (1.34 ± 0.20 Pa vs. 3.80 ± 0.59 Pa, respectively, p = 0.0001). This decrease was shown by a significant reduction in WSS and WSS contours in the thoracic aorta (from 3.10 ± 0.27 Pa to 1.34 ± 0.11Pa, p = 0.043) and renal arteries (from 4.40 ± 0.25 Pa to 1.50 ± 0.22 Pa p = 0.043). Conclusions: Post-operative remodelling of the aorta after TEVAR for TBAD improved hemodynamic patterns reflected by flow, velocity and WSS with an accuracy of 99%.

Indications for Thoracic EndoVascular Aortic Repair (TEVAR): A Brief Review

The utility of Thoracic EndoVascular Aortic Repair (TEVAR) continues to progress at a very rapid rate. Initially implemented for the treatment of thoracic aortic aneurysms, TEVAR has evolved to treat a variety of aortic pathologies and reduce overall morbidity and mortality rates compared with traditional open surgical repair. Given the rapidly evolving nature of endovascular thoracic intervention, we hereby briefly review the current literature on the evolving applications of TEVAR. TEVAR continues to rapidly evolve and is being applied to a growing number of aortic pathologies. Given the perioperative, short- and mid-term morbidity and mortality rates, TEVAR is quickly surpassing traditional open surgical intervention as the ideal procedure for patients undergoing intervention of the descending thoracic aorta and applicability to ascending and arch pathologies is being explored. However, as more data becomes available TEVAR may be associated with higher rates of reoperative requirements. Data remains limited on the long-term efficacy of the intervention and should continue to be investigated.