Endovascular vs. Open Repair of Complicated Acute Type B Aortic Dissections

Five-year results of the STABLE II study for the endovascular treatment of complicated, acute type B aortic dissection with a composite device design

OBJECTIVE

To provide the five-year outcomes of the use of a composite device (proximal covered stent-graft + distal bare stent) for endovascular repair of patients with acute, type B aortic dissection complicated by aortic rupture and/or malperfusion.

METHODS

STABLE II was a prospective, multicenter study of the Zenith Dissection Endovascular System (William Cook Europe, Denmark). Patients were enrolled between August 2012 and January 2015 at sites in the United States and Japan. Five-year follow-up was completed by January 2020.

RESULTS

In total, 73 patients (mean age 60.7±10.9 years; 65.8% male) with acute type B dissection complicated by malperfusion (72.6%), rupture (21.9%), or both (5.5%) were enrolled. Patients were treated with either a composite device (79.5%) or the proximal stent-graft alone (no distal bare stent, 20.5%). Dissections were more extensive in patients who received the composite device (408.9±121.3 mm) than in patients who did not receive a bare stent (315.9±100.1 mm). Mean follow-up was 1209.4±754.6 days. Freedom from all-cause mortality was 80.3%±4.7% at one year and 68.9%± 7.3% at five years. Freedom from dissection-related mortality remained at 97.1%±2.1% from one-year through five-year follow-up. Within the stent-graft region, the rate of either complete thrombosis or elimination of the false lumen increased over time (82.1% of all patients at five years vs. 55.7% at first post-procedure CT), with a higher rate at five years in patients who received the composite device (90.5%) compared with patients without the bare stent (57.1%). Throughout follow-up, overall true lumen diameter increased within the stent-graft region, and overall false lumen diameter decreased. At five years, 20.7% of patients experienced a decrease in maximum transaortic diameter within the stent-graft region, 17.2% experienced an increase, and 62.1% experienced no change. Distal to the treated segment (but within the dissected aorta), 23.1% of patients experience no change in transaortic diameter at five years; a bare stent was deployed in all these patients at the procedure. Five-year freedom from all secondary intervention was 70.7%±7.2%.

CONCLUSIONS

These five-year outcomes indicate a low rate of dissection-related mortality for the Zenith Dissection Endovascular System in the treatment of patients with acute, complicated type B aortic dissection. Further, these data suggest a positive influence of composite device use on false lumen thrombosis. Continuous monitoring for distal aortic growth is necessary in all patients.

Spinal Cord Ischemia in the Setting of Acute Type B Aortic Dissection: Successful Rescue with Thoracic Endovascular Aortic Repair

We report 2 cases of successful thoracic endovascular aortic repair (TEVAR) for acute type B aortic dissection (ABAD) complicated with spinal cord ischemia (SCI). Case 1. A 70-year-old gentleman found with an uncomplicated ABAD with false lumen occluded, developed SCI shortly after admission during the initial medical management. Cerebrospinal fluid drainage (CSFD) was initiated followed by emergent TEVAR. SCI improved, and the patient was discharged. Case 2. A 52-year-old gentleman developed uncomplicated ABAD with patent false lumen. 5 hours after admission, he developed SCI during the initial medical management. Emergent TEVAR was performed followed by CSFD, and the SCI improved before discharge. These cases prompted us to address prompt TEVAR for primary entry closure and true lumen dilatation with postoperative hypertensive management to relieve the dynamic obstruction of the segmental arteries responsible for the compromised spinal cord circulation in complicated ABAD.

Hospitalization Cost and In-hospital Outcomes Following Type B Thoracic Aortic Dissection Repair

BACKGROUND

Several studies have reported lower mortality and morbidity after thoracic endovascular aortic repair (TEVAR) when compared to open surgical repair (OSR) in the treatment of type B aortic dissection (TbAD). However, there are few studies in the literature on the cost of both treatment options. Thus, the aim of this study is to focus on in-hospital outcomes and cost associated with TbAD repair procedures in a national database in the United States.

METHODS

A retrospective review of the Premier Healthcare Database (PHD) between June 2009 and March 2015 was performed. ICD-9-CM codes were used to identify patients who underwent OSR or TEVAR for TbAD. Endpoints included in-hospital adverse events, in-hospital mortality and hospitalization cost. Logistic regression models and generalized linear models were used to assess the impact of treatment type on the main outcomes.

RESULTS

Out of 1752 patients with TbAD, 54.3% underwent OSR and 45.7% underwent TEVAR. Patients in the TEVAR group were older [median age, 64 (IQR 54-73) vs. 59 (IQR 49-70), P < 1] and more likely to have preexisting comorbidities. IAE rates were 78.6% for the OSR group compared to 43.1% for the TEVAR group, P < 0.001. Patients in the OSR group showed significantly higher in-hospital mortality (15.3% vs. 5.9%, P < 0.001). After adjusting for potential confounders, OSR was associated with a 5-fold increase in IAE [aOR(95%CI): 4.8 (3.8-6.1), P < 0.001] and a 3-fold increase in in-hospital mortality [aOR(95%CI): 3.3 (2.1-5.1), P < 0.001]. In regards to charges related to the hospital stay, total cost was significantly higher among patients undergoing OSR $53,371 ($39,029-$80,471) vs. TEVAR $45,311 ($31,479-$67,960), P < 0.001.

CONCLUSION

The present study shows that TEVAR presents an advantage in terms of morbidity, mortality and cost when compared to OSR in the treatment of TbAD. However, long-term cost-effectiveness of both procedures remains unknown. Further research is warranted to see whether the superiority of TEVAR is maintained over time.

Computed tomography findings and in-hospital mortality in patients with rupture of type B aortic dissection

Background

The relationships between the computed tomography (CT) findings and outcomes of patients with ruptured type B aortic dissection have not been clarified.

Purpose

To evaluate the initial CT findings of patients with ruptured type B aortic dissection and investigate the relationships between the initial CT findings and in-hospital mortality.

Material and Methods

This study was approved by the institutional review board. Thirty-three patients were diagnosed with ruptured Stanford type B aortic dissection at our hospital between 2007 and 2016 (21 men, 12 women; mean age = 76.1±10.7 years). We retrospectively evaluated the initial CT findings of ruptured type B aortic dissection and the relationships between clinical factors and in-hospital mortality using logistic regression analysis.

Results

Type B aortic dissections ruptured in the acute and chronic phases in 23 and 10 patients, respectively. The initial CT images showed various findings, including an open false lumen (58%), arch involvement (88%), hematomas in the pleural space (55%), hematomas in the pericardial space (18%), and the extravasation of vascular contrast material (12%). The mean maximum diameter of the affected aorta was 49.5 ± 16.1 mm. Among the 33 patients, 14 died at hospital. Female gender (hazard ratio = 10.284; 95% confidence interval [CI] = 1.61–65.54; P = 0.0136) and the presence of a hematoma in the pleural space (hazard ratio = 6.803; 95% CI = 1.07–43.24; P = 0.0421) were found to be predictors of in-hospital mortality.

Conclusion

Female gender and the presence of a hematoma in the pleural space are significant predictors of in-hospital mortality in patients with ruptured type B aortic dissection.

Endovascular Repair in Acute Complicated Type B Aortic Dissection: 3-Year Results from the Valiant US Investigational Device Exemption Study

Acute complicated type B aortic dissection (TBAD) is a potentially catastrophic, life-threatening condition. If left untreated, there is a high risk of aortic rupture, irreversible organ or limb damage, or death. Several risk factors have been associated with acute complicated TBAD, including age and refractory hypertension. In the acute phase, even uncomplicated patients are more prone to develop complications if hypertension and pain are left medically untreated. Innovations in stent graft technologies have incrementally improved outcomes since their first use for this condition in 1999, though improvement is needed in mitigating periprocedural complications, adverse events, and mortality. In the past decade, endovascular repair has become the preferred treatment because of its superior outcomes to open repair and medical therapy. The Valiant Captivia Thoracic Stent Graft System is a third-generation endovascular stent graft with advancements in minimally invasive delivery, conformability to the anatomy, and the minimization of adverse sequelae. Herein, this stent graft is briefly reviewed and its 3-year outcomes are presented. Freedom from all-cause and dissection-related mortality was 79.1% and 90.0%, respectively. The Valiant Captivia Stent Graft represents a safe, effective intervention for acute complicated TBAD. Continued surveillance is needed to verify its longer-term durability.

Thoracic endovascular aortic repair for complicated chronic type B aortic dissection in a patient on hemodialysis with recurrent ischemic colitis

We present a successful case of thoracic endovascular aortic repair (TEVAR) for chronic Stanford type B aortic dissection (B-AD) with recurrent ischemic colitis. The patient was a 56-year-old woman with abdominal pain as the main complaint who had two operations previously: the total arch replacement 8 years ago and the Bentall 7 years ago for acute Stanford type A aortic dissection. Her abdominal pain worsened as her blood pressure became low during her hemodialysis treatment. An enhanced computed tomography scan was performed on the patient and showed chronic B-AD that occurred from the distal anastomotic part of the total arch graft to the bilateral common iliac arteries. The celiac artery and superior mesenteric artery (SMA) arose from the true lumen, and these were compressed by the expanded false lumen. Her complicated chronic B-AD was treated with the Zenith Dissection Endovascular System, and its procedure was performed as her proximal entry tear was covered by a proximal tapered Zenith TX2 stent graft, supplemented by a noncovered aortic stent extending across both renal arteries, the SMA, and the celiac artery. Seven days after this operation, enhanced computed tomography showed that the patient's true lumen was expanded and her blood flow to the true lumen and SMA was improved. On the other hand, her false lumen tended to be thrombosed. Consequently, she was discharged 10 days after the operation without any postoperative complications as she had no abdominal complaints even though she underwent hemodialysis three times per week after the operation. We believe that TEVAR supplemented by a noncovered aortic stent is an effective treatment, even for highly chronic B-AD in dialysis patients.

[Endovascular versus conventional vascular surgery - old-fashioned thinking? Part 1: interventions on the aorta]

Endovascular therapy has widely replaced conventional open vascular surgical reconstruction. For this reason both techniques were widely considered to be competing approaches. Evidence-based data from randomized prospective trials, meta-analyses and clinical registries, however, demonstrated that both techniques should be used to complement each other. It became increasingly more evident that the use of either procedure depends on the underlying disease and the anatomical conditions, whereby a combination of both (hybrid approach) may be the preferred option in certain situations. This review focuses on the treatment of complicated acute type B aortic dissection, descending thoracic aortic aneurysms, thoracoabdominal aortic aneurysms as well as asymptomatic and ruptured abdominal aortic aneurysms.

Emergency thoracic aortic stent grafting for acute complicated type B aortic dissection after a previous abdominal endovascular aneurysm repair

We report a case of acute type B aortic dissection with the complication of bowel ischemia and abdominal stent graft compression treated by emergency thoracic aortic stent grafting after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA). A 69-year-old male was admitted to our hospital for sudden thoraco-abdominal pain. He had past treatment history of EVAR for AAA half a year ago. A computed tomography (CT) showed acute type B aortic dissection, and conservative treatment was initially performed. Three days after occurrence of aortic dissection, worsened abdominal pain and melena were observed. CT showed that the true lumen and abdominal stent graft was compressed by the false lumen. Emergency thoracic endovascular repair (TEVAR) was performed to close the entry tear. After the operation, the image views and the symptoms were improved. The state was still stable 6 months later. TEVAR for acute type B aortic dissection can become one of the effective treatments.

Endovascular management of rupture in acute type B aortic dissections

OBJECTIVE

Reports of thoracic endovascular aortic repair (TEVAR) for complicated acute type B aortic dissection (ABAD) bring together a large range of clinical presentations. With a 30 day mortality of 50% when managed with open surgery, rupture is the most devastating complication of ABAD. This study investigated the outcome of TEVAR for ABAD complicated by rupture (r-ABAD) to assess the results of this particularly critical subgroup.

METHODS

A review of consecutive TEVAR for r-ABAD in two tertiary referral centers was performed using a prospectively maintained database.

RESULTS

Between 2000 and 2013, 24 patients (mean age 71 years; 14 males) underwent TEVAR for r-ABAD. Sixteen (67%) were in shock (Systolic blood pressure <80 mmHg) before surgery. Seven patients had coverage of the left subclavian artery, of whom four had partial arch debranching procedures via cervical access concomitant with TEVAR. Median length of aortic coverage was 150 mm, median proximal oversizing was 13.3% (range 6.2-33.3%). Technical success was achieved in 100%. There were four in hospital deaths (16%). Two patients (8%) had paraplegia, but neither stroke nor renal insufficiency requiring dialysis occurred. During a mean follow up of 28 months, there was one aortic dissection related death and eight patients (40% of the surviving patients) required re-intervention. All re-interventions were managed endovascularly. At last follow up CT scan, eight patients (40%) had complete remodeling of the aortic wall.

CONCLUSION

With 16% in hospital mortality and 8% early major complications, this study confirms the feasibility of TEVAR for r-ABAD with a lower peri-operative morbidity and mortality rate compared with open surgery. Given the high rate of re-intervention, close follow up is required in surviving patients.