Endovascular Stent-graft Therapy Research Articles

Leiomyosarcoma Presenting as Rupture With a Type II Endoleak After Thoracic Endovascular Aortic Repair.

Endovascular stent-graft therapy is a commonly performed procedure for aortic lesions worldwide and complications unique to stent grafts, such as postoperative endoleaks, are well known. However, as this treatment modality becomes more popular, physicians should carefully monitor for other unexpected complications, which may not always be related to the graft. This study presents a case of leiomyosarcoma of the aorta that developed during follow-up for a type II endoleak (T2EL) after thoracic endovascular aortic repair. The presence of the T2EL hindered the diagnosis of the sarcoma at an early stage. These findings suggest that an apparent aneurysm that grows suddenly during follow-up after stent grafting should raise the index of suspicion for a neoplasm as well as an endoleak.

ENDOVASCULAR MANAGEMENT OF TYPE B ACUTE AORTIC DISSECTION IN NON-SYNDROMIC PATIENTS WITH A FAMILY HISTORY OF AORTIC DISEASE

While a genetic basis for thoracic aortic aneurysm and dissection is well established, little is known about endovascular stent graft therapy (TEVAR) outcomes in patients with family history of aortic disease following Type B acute aortic dissection (TBAD). Patients enrolled in the International

Traumatic aortic rupture - diagnosis and managment

Road traffic accidents are the main cause of traumatic aortic ruptures, mostly in combination with other severe injuries. The pre-hospital mortality rate is high. Suspected aortic trauma, following ahigh traumatic aortic injury score, is an indication for computer tomography. Injuries are triaged and the treatment priority of the aortic trauma is ascertained based on the severity of the aortic and concomitant injuries and the condition of the patient. Until definitive treatment of the aortic lesion is completed, the blood pressure of the patient must be kept low. GradeI andII lesions can be managed under strict monitoring with initial conservative treatment in individual cases. GradeIII (contained perforation) and gradeIV (open rupture) lesions need surgical or interventional treatment as swiftly as possible. In selected cases, adelayed treatment can also be advantageous.The endovascular stent graft therapy has established itself as the preferred form of treatment.

SUN-496 A Perioperative Risk For Exacerbation of Hypercalcemia in Primary Hyperparathyroidism

[Introduction] Primary hyperparathyroidism (PHPT) occasionally presents a hyperparathyroid crisis which provides a pivotal cue for its diagnosis. However, the perioperative risk for exacerbation of hypercalcemia has been unknown in PHPT. We herein report 2 cases of PHPT which presented a hyperparathyroid crisis during the perioperative period for other complications. [Case presentaion] Case 1; A 81-year-old man was referred to our center due to urinary stone and hypercalcemia. Baseline laboratory data were as follows; corrected serum Ca 11.2 mg/dl; serum P 2.0 mg/dl; whole PTH 89.6 pg/ml, eGFR 49 ml/min/1.73m2. CT revealed a neck tumor of 10 mm with 99mTc-MIBI uptake, which was considered as a cause of PHPT. Simultaneously, CT also pointed out thoracic aortic aneurysm of 70 mm. Therefore, he underwent endovascular stent graft therapy prior to tumorectomy of PHPT. The procedure of stent graft was successfully performed but also caused subarachnoid hemorrhage and acute kidney injury (AKI). Corrected Ca level was subsequently elevated to 12.4 mg/dl, implying an exacerbation of PHPT. He received 60 mg denosumab administration in order to control Ca level complicated with AKI, resulted in improvement of hypercalcemia. However, PTH level was not significantly changed (57.4 pg/ml) during the period, indicated that lower urinary excretion of calcium due to AKI was the main cause of Ca level elevation. Case 2; A 57-year-old woman was admitted to our center due to incidental hypercalcemia. Baseline laboratory data were as follows; corrected serum Ca 12.5 mg/dl; serum P 2.1 mg/dl; whole PTH 140 pg/ml, eGFR 74 ml/min/1.73m2. CT revealed a neck tumor of 17 mm with 99mTc-MIBI uptake, considered as a cause of PHPT. Unexpectedly, MR imaging revealed meningioma of 48 mm on the Turkish saddle. She underwent embolization and removal of meningioma prior to tumorectomy of PHPT. After surgery, she had a persistent disturbance of consciousness because of hypernatremia (over 160 mM) and hypercalcemia (17.2 mg/dl) complicated with AKI. As a hyperparathyroid crisis, we administered 60 mg denosumab and continued fluid replacement therapy, leading to gradual improvement of electrolyte imbalances. PTH level was significantly elevated to 443 pg/ml compatible with a hyperparathyroid crisis. Her serum Ca level was kept lower than 12 mg/dl by denosumab for more than 3 months. [Conclusion] Our cases suggested that serum Ca level in PHPT could be influenced by perioperative conditions, although the trigger for exacerbation of PHPT remains unclear. Management of PHPT should be considered before surgery for other complications. Denosumab is useful for management of PHPT regardless of renal function.

Unusual complications of endovascular repair of the thoracic aorta: MDCT findings

With the development of minimally invasive surgical techniques, endovascular stent-graft placement has become an accepted and widely used alternative to the traditional surgical repair of aortic disease and is gaining acceptance as the treatment of choice. Many studies show that endovascular stent-graft therapy is safe and effective, although complications related to this treatment are also recognised. Although the incidence of major complication is low, neurological sequelae remain the major concern of endovascular repair. With growing experience, however, the spectrum of mid- and long-term complications has broadened to include potentially disastrous events, other than paraplegia or stroke, that require diligent surveillance. Three-dimensional data sets acquired quickly by multidetector computed tomography (MDCT) allow multiplanar reformations and 3D viewing, as well as quantitative assessment of vessel lumens, walls and surroundings. Although a large portion of radiologists will not be involved in the actual endograft deployment, many will be involved in the interpretation of postprocedural surveillance studies. Accordingly, the goal of this report is to summarise our experience with the presentation, diagnostic approach, management and outcomes of these unusual, but potentially catastrophic, postendovascular aortic repair complications to highlight their significance and increase familiarity with them among the imaging community. Increasing awareness of these complications may facilitate rapid diagnosis and/or triage and treatment.

Stent-assisted Embolization as “Bailout” Option in Aortic Aneurysm

The authors report two cases of stent-assisted embolization (SAE) in the aorta. In one case, SAE was performed for treatment of a pseudoaneurysm; the procedure consisted of stent placement and embolization with an AMPLATZER Vascular Plug and detachable coils through the stent struts. In the second case, SAE was performed to stop acute bleeding from an aortoureteral fistula. Before SAE in this case, the aortic bifurcation was reconstructed with self-expandable and balloon-expandable stents. SAE was technically successful in both cases. SAE for aortic pathologic processes may be useful in selected cases as an alternative to surgery or endovascular stent-graft therapy.

Thoracic endovascular stent-graft therapy in aortic dissection

Aortic dissection is an uncommon but highly lethal condition with a mortality rate of 1-2% per hour within the first 24 h when the ascending aorta is affected and remains a surgical domain. For the treatment of type B aortic dissection, however, endovascular techniques became available recently and are increasingly popular. This review focuses on current indications and results of thoracic endovascular stent-graft therapy in aortic dissection. Uncomplicated type B aortic dissections should be managed medically and kept under surveillance for delayed expansion in 20-50% patients over 4 years. Endovascular treatment should be considered in the setting of impending or actual complications, for example, when the aortic diameter exceeds 55-60 mm, in the case of uncontrolled pain or blood pressure with evidence of malperfusion syndrome or rapid growth of the dissecting aneurysm (>1 cm/year). In both complicated acute and chronic type B aortic dissections, endovascular therapy may emerge as an attractive alternative to open surgery. However, in uncomplicated chronic type B aortic dissection, endovascular therapy failed to improve outcomes over optimal medical therapy within 2 years despite aortic remodeling. Endovascular stent-graft therapy for aortic dissection is emerging with good mid-term results. Further indications, that is, aortic arch dissection and uncomplicated acute aortic dissections, are under evaluation.

Endovascular repair of the thoracic aorta in the post-FDA approval era

Endovascular repair of thoracic aortic disease is rapidly progressing as an alternative to open surgical therapy. In March of 2005, the Gore TAG thoracic endoprosthesis (W. L. Gore & Associates, Inc, Flagstaff, Ariz) received Food and Drug Administration (FDA) approval for the treatment of descending thoracic aortic aneurysms. Subsequently, off-label use of the technology expanded to include additional thoracic aortic diseases. The purpose of this study was to examine whether the outcomes with this device changed after the inclusion and exclusion criteria of FDA-controlled trials no longer governed patient selection. A retrospective analysis was performed on all patients who underwent endovascular repair of the thoracic aorta with the Gore TAG device at our institution between March 23, 2005, and September 8, 2006. Fifty consecutive patients with a broad range of aortic pathologic conditions were included in the study. The results in this group compared with those of the phase II trial included the following: length of stay, 7.5 versus 7.6 days (P = .97); intensive care unit stay, 3.7 versus 2.6 days (P = .61); 30-day mortality, 2.0% versus 1.5% (P = .68); spinal cord injury, 2% versus 3% (P = .89); stroke, 4% versus 4% (P = .67); early endoleaks, 26% versus 4% (P < .01); and late endoleaks, 18% versus 7% (P = .08). At 1 year, overall survival was 92% compared with 82% in the phase II trial. In the post-FDA approval era, endovascular stent-graft therapy is frequently applied to patients with more challenging thoracic aortic anatomy and a wide range of pathologic conditions. Our results in this group are similar to outcomes reported for patients with descending thoracic aortic aneurysm exclusively.

Abdominal Aortic Aneurysm: Can the Arterial Phase at CT Evaluation after Endovascular Repair Be Eliminated to Reduce Radiation Dose?

To retrospectively determine if arterial phase computed tomographic (CT) imaging is necessary for follow-up imaging of patients who have undergone endovascular stent-graft therapy for abdominal aortic aneurysm. This HIPAA-compliant study was exempt from institutional review board approval; informed patient consent was waived. Eighty-five patients (66 men, 19 women; mean age, 66 years; range, 45-81 years) underwent 110 multidetector CT examinations after endovascular repair of abdominal aortic aneurysms. Nonenhanced CT images were obtained. Intravenous contrast material was then injected at 4 mL/sec, and arterial and venous phase (60 seconds) CT images were obtained. The nonenhanced and venous phase images were evaluated to determine if an endoleak was present. Subsequently, arterial phase images were analyzed. The effective dose was calculated. Ninety-five percent confidence intervals as indicators of how often arterial phase imaging would contribute to the diagnosis of endoleak were determined. Twenty-eight type II endoleaks were detected by using combined nonenhanced and venous phase acquisitions. Twenty-five of the 28 endoleaks were also visualized during the arterial phase. Three type II endoleaks were seen only during the venous phase. The arterial phase images depicted no additional endoleaks. Seventy-eight CT examinations performed in 67 patients revealed no endoleak during the venous phase. The arterial phase images also depicted no endoleaks at these examinations. Thus, for no more than 3.1% of all examinations, there was 95% confidence that arterial phase imaging would depict an endoleak missed at venous phase imaging. Arterial phase imaging contributed to a mean of 36.5% of the effective dose delivered. Study results indicate that arterial phase imaging may not be necessary for the routine detection of endoleaks. Radiation exposure can be decreased by eliminating this phase.

Endovascular stent graft repair of abdominal and thoracic aortic aneurysms: a ten-year experience with 817 patients.

On November 23, 1992, the first endovascular stent graft (ESG) repair of an aortic aneurysm was performed in North America. Following the treatment of this patient, we have continued to evaluate ESG over the past 10 years in the treatment of 817 patients. Abdominal (AAA) or thoracic (TAA) aortic aneurysms are a significant health concern traditionally treated by open surgical repair. ESG therapy may offer protection from aneurysm rupture with a reduction in procedure morbidity and mortality. Over a 10-year period, 817 patients were treated with ESGs for AAA (723) or TAA (94). Patients received 1 of 12 different stent graft devices. Technical and clinical success of ESGs was reviewed, and the incidence of procedure-related complications was analyzed. The mean age was 74.3 years (range, 25-95 years); 678 patients (83%) were men; 86% had 2 or more comorbid medical illnesses, 67% of which included coronary artery disease. Technical success, on an intent-to-treat basis was achieved in 93.8% of patients. Primary clinical success, which included freedom from aneurysm-related death, type I or III endoleak, graft infection or thrombosis, rupture, or conversion to open repair was 65 +/- 6% at 8 years. Of great importance, freedom from aneurysm rupture after ESG insertion was 98 +/- 1% at 9 years. There was a 2.3% incidence of perioperative mortality. One hundred seventy five patients died of causes not related to their aneurysm during a mean follow-up of 15.4 months. Stent graft therapy for aortic aneurysms is a valuable alternative to open aortic repair, especially in older sicker patients with large aneurysms. Continued device improvements coupled with an enhanced understanding of the important role of aortic pathology in determining therapeutic success will eventually permit ESGs to be a more durable treatment of aortic aneurysms.