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 5-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: Study of Thoracic Aortic Type B Dissection Using Endoluminal Repair (STABLE) II was a prospective, multicenter study of the Zenith Dissection Endovascular System (William Cook Europe). 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). The mean follow-up was 1209.4 ± 754.6 days. Freedom from all-cause mortality was 80.3% ± 4.7% at 1 year and 68.9% ± 7.3% at 5 years. Freedom from dissection-related mortality remained at 97.1% ± 2.1% from 1-year through 5-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 5 years vs 55.7% at first postprocedure computed tomography), with a higher rate at 5 years in patients who received the composite device (90.5%) compared with patients without the bare stent (57.1%). Throughout the follow-up, overall true lumen diameter increased within the stent-graft region, and overall false lumen diameter decreased. At 5 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 5 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 5-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.

STABLE II clinical trial on endovascular treatment of acute, complicated type B aortic dissection with a composite device design.

OBJECTIVE: To evaluate the safety and effectiveness of a composite device design (covered stent graft and bare metal stent) for the treatment of patients with acute, complicated type B aortic dissection (TBAD) presenting with aortic rupture and/or branch vessel malperfusion. METHODS: In this prospective, nonrandomized, multicenter study, 73 patients (65.8% male; mean age, 60.7 years) with acute, complicated TBAD were enrolled between August 2012 and January 2015 to receive treatment with the Zenith Dissection Endovascular System (William Cook Europe, Aps, Bjaeverskov, Denmark) at institutions in the United States and Japan. The primary safety end point was the rate of freedom from major adverse events at 30 days, and the primary effectiveness end point was the rate of survival at 30 days. This article reports primary outcomes at 30 days and follow-up results through 1 year, reflecting study data as of March 2018. RESULTS: Of 73 patients, 20 presented with aortic rupture (27%) and 57 presented with branch vessel obstruction/compromise (78%), including 4 patients presenting with both conditions. The covered stent graft was used in all patients (median, 1; range, 1-3; 1 stent graft used in 64.4%; 47/73), and the bare metal dissection stent was used in 58 of 73 patients (79.5%). Thirty-day mortality occurred in five patients (6.8%): one procedure related, three unrelated to dissection repair, and one indeterminate. Thirty-day major adverse events included myocardial infarction (1.4%), bowel ischemia (1.4%), renal insufficiency/renal failure requiring dialysis (6.8%), stroke (6.8%), paraplegia or paraparesis (5.5%), and prolonged ventilatory support (13.7%). Nine deaths occurred from 31 to 365 days (only one death related to dissection repair); the Kaplan-Meier estimate of freedom from all-cause mortality was 80.3% ± 4.7% at 1 year. Within 365 days, 9 of 73 patients (12.3%) underwent 10 secondary interventions; no patients required conversion to open surgery. At the 12-month follow-up, complete or partial thrombosis of the false lumen was seen in 100% of patients (46/46) within the stent graft region and in 97.4% of patients (38/39) within the dissection stent region. Growth (>5 mm) of the maximum transaortic diameter was observed in 14.9% of patients (7/47) in the stent graft region and in 38.5% of patients (15/39) within the dissection stent region at 12 months. CONCLUSIONS: Thirty-day and 1-year results from the STABLE II study demonstrated favorable clinical and anatomical outcomes for the treatment of rupture and malperfusion in the setting of acute, complicated TBAD. Five-year follow-up is ongoing.

Stent-assisted balloon-induced intimal disruption and relamination in aortic dissection repair: the STABILISE concept.

OBJECTIVES: The study objective was to describe the Stent-Assisted Balloon-Induced Intimal Disruption and Relamination in Aortic Dissection Repair technique for aortic dissection repair using proximal descending aortic endografting with distal aortic relamination through bare-metal stent and balloon-induced intimal disruption with immediate intimal reapposition. METHODS: Between April 2007 and September 2011, 11 selected patients (10 male; median age, 50 years) underwent proximal descending aortic endografting plus stent-assisted balloon-induced intimal disruption of the thoracoabdominal aorta to treat complicated aortic dissection (7 type A, 4 acute type B). Patients with type A dissection underwent open surgical intervention plus adjunctive retrograde endovascular repair. Serial computed tomography angiography was used to assess aortic remodeling. RESULTS: There were no intraprocedural complications. Thirty-day incidence of death, stroke, and paralysis/visceral ischemia was 9% (n = 1), 0%, and 0%, respectively. Median follow-up was 18 months (range, 4-54 months). Two patients (18%) required secondary endovascular reintervention. No late adverse events or aortic-related deaths occurred. Complete false lumen obliteration occurred in 90% (n = 10) of patients, with stable maximal diameters in the thoracic (P = .6) and abdominal aortas (celiac trunk: P = .34; renal; P = .6; infrarenal: P = .7) at latest follow-up. CONCLUSIONS: The Stent-Assisted Balloon-Induced Intimal Disruption and Relamination in Aortic Dissection Repair approach is a feasible endovascular technique that shows promise to achieve complete repair of the dissected aorta by inducing complete false lumen obliteration. The restoration of uniluminal flow in the thoracoabdominal aorta has the potential to improve long-term outcomes. Prospective, multicenter investigations are required to implement this strategy more broadly.

Hybrid proximal surgery plus adjunctive retrograde endovascular repair in acute DeBakey type I dissection: superior outcomes to conventional surgical repair.

OBJECTIVE: The present study compared the outcomes between conventional surgery and the hybrid approach of proximal surgery with adjunctive retrograde descending aortic endografting plus distal bare metal stenting in acute DeBakey type I dissection. METHODS: From 2003 to 2011, 61 patients underwent surgical management for acute type A aortic dissection at our institution. Of these, 37 were DeBakey type I dissections: 18 patients (group 1) received conventional surgical repair alone, and 19 (group 2) underwent conventional hybrid surgery with adjunctive retrograde descending aortic stent grafting plus distal bare metal stenting. RESULTS: The patients' baseline characteristics were comparable, including the incidence of preoperative malperfusion syndromes (P = .23). The intraoperative and postoperative characteristics were similar, except 4 (22%) patients in group 1 (vs 0 in group 2) had ongoing malperfusion postoperatively (P = .04). Overall, hospital mortality was 11% (n = 2) for group 1 versus 5% (n = 1) for group 2. At a mean follow-up of 50 months, 4 (25%) subjects in group 1 required secondary thoracoabdominal aortic reintervention versus none in group 2 (P = .03). CONCLUSIONS: The use of adjunctive retrograde descending aortic endografting plus distal bare metal stenting during acute DeBakey type 1 dissection repair is a feasible method to enhance thoracoabdominal remodeling. This hybrid strategy improves perioperative outcomes and decreases late distal aortic complications compared with conventional surgical repair for acute DeBakey type I dissection. A prospective, multicenter study is warranted to definitively assess this promising new treatment paradigm.

Aortic false lumen thrombosis induction by embolotherapy (AFTER) following endovascular repair of aortic dissection.

PURPOSE: To report the use of a technique (AFTER: aortic false lumen thrombosis induction by embolotherapy) to achieve false lumen (FL) thrombosis and aortic remodeling in patients with residual FL patency after initial endovascular repair of aortic dissection. METHODS: Between January 2003 and January 2010, 31 patients underwent staged total aortic and branch vessel endovascular reconstruction (STABLE) of type A (n = 13) and type B (n = 18) dissection. Of these, 10 patients (5 men; mean age 61 years) who had undergone repair of 4 acute type A, 3 acute type B, and 3 chronic type B dissections demonstrated re-entry tear(s) and FL patency associated with aortic expansion ≥5 mm or flow into a persistently dilated aortic segment. Catheter-directed embolization using coils, glue, or occlusion balloons was performed via a transfemoral approach to the true lumen at a mean of 7 months (range <1 to 26) after initial repair. RESULTS: Technical success was achieved in all patients, with no intraoperative complications. Thirty-day morbidity and mortality was nil. Mean follow-up was 63 months (range 13-96). Reversal or stabilization (<5-mm increase) of thoracoabdominal aortic growth occurred in 9 patients. Complete thrombosis of the thoracic and abdominal FL occurred in 2 patients. In 4, FL occlusion and subsequent thrombosis of the upstream thoracic segment was achieved. Four demonstrated partial FL thrombosis in the thoracic and abdominal aorta. One patient with chronic aneurysmal type B dissection died 4 months post-embolization from aortic rupture. CONCLUSION: The AFTER strategy appears to be a safe and promising adjunctive endovascular approach to treat residual FL patency or aortic enlargement post endovascular repair of aortic dissection. Elimination of FL flow and stabilization of aortic expansion may reduce the risk of late distal aortic complications.

Combined proximal stent grafting plus distal bare metal stenting for management of aortic dissection: Superior to standard endovascular repair?

OBJECTIVES: The present study compared the outcomes between combined proximal descending aortic endografting plus distal bare metal stenting and conventional proximal descending aortic stent-graft repair in patients with type A and type B aortic dissection. METHODS: From January 2003 to December 2010, 63 patients underwent endovascular treatment for acute (type A, 24; type B, 21) and chronic (type B, 18) aortic dissection. Of these, 40 patients underwent proximal descending aortic endografting plus distal bare metal stenting (group 1), and 23 underwent proximal descending stent-graft repair alone (group 2). All patients with type A dissection underwent open surgical intervention plus adjunctive retrograde endovascular repair. RESULTS: The patients were comparable for baseline characteristics and treatment indicators, but more group 1 patients were active smokers (P = .03). The intraoperative characteristics were also similar, although 4 patients, all in group 2, developed malperfusion syndrome postoperatively (P = .02). The overall hospital mortality was 6%. At a mean follow-up of 49 months, 9 group 2 patients (43%) required unplanned secondary intervention compared with 4 in group 1 (11%; P = .007). Reintervention for thoracoabdominal aortic aneurysm or visceral ischemia was performed in 4 patients (19%) from group 2 (P = .03). Late aortic-related deaths occurred in 1 (5 %) and 2 (5%) patients in groups 1 and 2, respectively. CONCLUSIONS: Combined proximal descending aortic endografting plus distal bare metal stenting for aortic dissection provides favorable short-term outcomes and decreases late distal aortic complications compared with conventional endovascular repair. These results support a more widespread application of this approach. A prospective, randomized trial is needed before definite conclusions can be made.

Combined proximal endografting with distal bare-metal stenting for management of aortic dissection.

BACKGROUND: Established endovascular treatments for aortic dissection often result in incomplete aortic repair, potentially leading to late complications involving the distal aorta. To address the problems of incomplete true lumen reconstitution and late aneurysmal change, we report the midterm results of combined proximal endografting with distal true lumen bare-metal stenting (STABLE: Staged Total Aortic and Branch vesseL Endovascular reconstruction) in Stanford type A and B aortic dissection. METHODS: Between January 2003 and January 2010, 31 patients underwent staged total aortic and branch vessel endovascular reconstruction for management of acute (type A, 13; type B, 11) and chronic (type B, 7) aortic dissection. Proximal endografting was combined with bare-metal Z stent implantation in the distal true lumen. Patients with type A dissection underwent adjunctive treatment at operation. Computed tomography angiography was performed at baseline, 1 year, and annually thereafter to assess aortic remodelling. RESULTS: Primary technical success was 97%. Thirty-day rates of death, stroke, and permanent paraplegia/paresis were 3% (n=1), 0%, and 0%, respectively. Mean follow-up was 57.3 months (range, 5 to 100 months). Overall survival was 60% at 100 months. Aortic-specific survival was 93%. Four patients (13%) underwent device-related reintervention. One (3%) late aortic-related death occurred. Thoracic (p=0.64) and abdominal (p=0.14) aortic dimensions were stable. The true lumen index increased significantly at follow-up. CONCLUSIONS: Staged total aortic and branch vessel endovascular reconstruction is a feasible ancillary endovascular technique to address the problems of distal true lumen collapse, incomplete aortic remodelling, and late aneurysm formation in aortic dissection.

Mesenteric embolization for lower gastrointestinal bleeding.

PURPOSE: Mesenteric embolization is an established treatment for lower gastrointestinal bleeding. The aim of this study was to determine the outcome of angiography and embolization and its influencing factors. METHODS: A prospective database of all mesenteric angiograms performed for lower gastrointestinal bleeding at a tertiary center between 1998 and 2008 was analyzed in combination with chart review. RESULTS: There were 107 angiograms performed during 83 episodes of lower gastrointestinal bleeding in 78 patients. Active bleeding was identified in 40 episodes (48%), and embolizations were performed in 37 (45%). One patient without active bleeding on angiogram also underwent embolization, making a total of 38 embolizations. Overall mortality was 7% with 4 deaths due to rebleeding and 2 deaths due to a medical comorbidity (respiratory failure, pneumonia). Short-term complications of angiography were false aneurysm (1 patient) and Enterobacter sepsis (1 patient). Long-term complications were groin lymphocele (1 patient) and late rebleed from collateralization (1 patient). In 43 episodes, angiography did not demonstrate active bleeding. Twelve (28%) of these patients continued to bleed, 9 of whom had successful surgery. Of the 38 patients who had embolizations, all had immediate cessation of bleeding. Nine patients (24%) later rebled; 5 of these patients required surgery and 3 had reembolizations. Of the 3 patients who underwent reembolization, 2 developed ischemic bowel and 1 stopped bleeding; surgery was required in 1 patient. CONCLUSIONS: Mesenteric angiography for lower gastrointestinal bleeding effectively identifies the site of bleeding in 48% of patients and allows embolization in 45%. Embolization achieves clinical success in 76% of patients but repeat embolization is associated with a high rate of complications.

Infected (mycotic) aneurysms: spectrum of imaging appearances and management.

Infected aneurysms are uncommon. The aorta, peripheral arteries, cerebral arteries, and visceral arteries are involved in descending order of frequency. Staphylococcus and Streptococcus species are the most common causative pathogens. Early clinical diagnosis of infected aneurysms is challenging owing to their protean manifestations. Clinically apparent infected aneurysms are often at an advanced stage of development or are associated with complications, such as rupture. Nontreatment or delayed treatment of infected aneurysms often has a poor outcome, with high morbidity and mortality from fulminant sepsis or hemorrhage. Current state-of-the-art imaging modalities, such as multidetector computed tomography and magnetic resonance imaging, have replaced conventional angiography as minimally invasive techniques for detection of infected aneurysms in clinically suspected cases, as well as characterization of infected aneurysms and vascular mapping for treatment planning in confirmed cases. Doppler ultrasonography allows noninvasive assessment for infected aneurysms in the peripheral arteries. Imaging features of infected aneurysms include a lobulated vascular mass, an indistinct irregular arterial wall, perianeurysmal edema, and a perianeurysmal soft-tissue mass. Perianeurysmal gas, aneurysmal thrombosis, aneurysmal wall calcification, and disrupted arterial calcification at the site of the infected aneurysm are uncommon findings. Imaging-guided endovascular stent-graft repair and embolotherapy can be performed in select cases instead of open surgery. Familiarity with the imaging appearances of infected aneurysms should alert the radiologist to the diagnosis and permit timely treatment, which may include endovascular techniques.

Controlled blunt microdissection for percutaneous recanalization of lower limb arterial chronic total occlusions: a single center experience.

BACKGROUND: Percutaneous techniques for the revascularization of symptomatic lower limb arterial chronic total occlusions (CTOs) remain suboptimal due to difficulty in safely and reliably crossing these heavily calcified lesions using standard guidewire and balloon technology. OBJECTIVES: The objective of this prospective study was to evaluate the technical success and safety of controlled blunt microdissection (CMD) for the treatment of resistant peripheral CTOs. METHODS: This series enrolled 36 patients (26 men; mean age 67 +/- 12 years), with 44 symptomatic CTOs (2 terminal aortic, 24 iliac, 16 femoral, and 2 popliteal), which had previously failed conventional percutaneous revascularization. CMD was carried out using a specialized prototype catheter. Actuation of the hinged jaws of this CMD catheter created a channel within the occluded arterial segment for guidewire passage, and subsequent angioplasty and stenting using standard procedures. The problem of subintimal CMD catheter passage, creating an eccentric channel, was addressed using a second novel device, the true-lumen reentry (LRE) catheter, which allowed reentry into the downstream lumen. RESULTS: Procedural success, evaluated angiographically, was achieved in 40 (91%) of the 44 CTOs. Fourteen (35%) of these 40 successful recanalizations required guidewire redirection, using the LRE catheter for lesion traversal. There were no complications related to CMD per se; although one patient experienced acute in-stent thrombosis, managed successfully with intra-arterial thrombolysis. CONCLUSIONS: We therefore conclude that CMD can be used safely and successfully to facilitate recanalization of resistant CTOs in the pelvic and lower limb arteries.

Staged endovascular treatment for complicated type B aortic dissection.

BACKGROUND: A 40-year-old man presented with acute chest and back pain, hypertension and anuria. Two years previously he had been diagnosed with acute uncomplicated type B aortic dissection. Following conservative management, with aggressive antihypertensive therapy and analgesia, he was monitored with 6-monthly surveillance CT scans. These demonstrated a complicated type B dissection with renal and iliac malperfusion. INVESTIGATIONS: Multislice CT, transthoracic and transesophageal echocardiography, digital subtraction aortography. DIAGNOSIS: Acute-on-chronic type B aortic dissection, complicated by aneurysmal dilatation of the thoracic aorta and visceral malperfusion. MANAGEMENT: Antihypertensive therapy; staged thoracoabdominal and branch vessel endoluminal repair (STABLE procedure), with stabilization of the dissection and rescue of renal function; CT imaging surveillance to monitor for any further complications.

Treatment of acute renal failure caused by renal artery occlusion with renal artery angioplasty.

BACKGROUND: Renovascular disease is a common cause of renal impairment and hypertension, particularly in the older population. Oligoanuric acute renal failure secondary to renal artery occlusion is not well recognized; however, it is potentially reversible if identified and treated. METHODS: Five patients presented to our institution with oligoanuric acute renal failure. Each had evidence of vascular disease, and a prerenal insult was identified. They were investigated with renal artery Doppler ultrasound or nuclear imaging before proceeding to percutaneous angioplasty and stent placement. RESULTS: The targeted kidney had relatively well-preserved renal size, and potential viability of the renal tissue was determined by nuclear scanning with parenchymal uptake of tracer. Percutaneous angioplasty and stent placement resulted in brisk reperfusion of the kidney and an immediate diuresis with improvement of renal function, avoiding supportive dialysis after the procedure. Contrast nephrotoxicity was identified in two of the five cases. CONCLUSION: Renal artery occlusion should be considered as a cause of oliguric acute renal failure, particularly in patients at high risk who present with a sudden deterioration of renal function, with nuclear imaging showing potentially viable renal tissue with relatively well-preserved renal size. Percutaneous revascularization should be considered in this group.