Reoperations After Failure of Stent Grafting for Type B Aortic Dissection: Report of Two Cases

Restrictive bare stent for prevention of stent graft-induced distal redissection after thoracic endovascular aortic repair for type B aortic dissection

BACKGROUND

Stent graft-induced distal redissection (SIDR) is one of the major concerns in the durability of endovascular repair for complicated Stanford type B aortic dissection. The characteristics and means of prevention of this complication remain unknown.

METHODS

From April 1997 to March 2010, 674 patients with type B aortic dissections were treated primarily by thoracic endovascular aortic repair (TEVAR) at our center. Criteria for inclusion in this study were treatment primarily with TEVAR and an estimated mismatch rate (ratio of distal diameter of stent graft to long diameter of true lumen) greater than 120%. By this protocol, 465 patients were included in this study and were retrospectively analyzed. Among them, 266 patients were treated in the acute phase, and 199 were treated in the chronic phase.

RESULTS

A total of 311 patients were treated with standard TEVAR and 154 patients with TEVAR + restrictive bare stent (RBS). The preoperative mismatch rate (measured as the preoperative long diameter of the true lumen at the level of the intended distal end of the stent graft) of the SIDR was significantly higher than that of the non-SIDR (192.7 ± 54.9% vs 131.9 ± 10.4%; P ＜ .05). The follow-up mismatch rate of the SIDR was significantly higher than that of the non-SIDR (145.4 ± 34.6 vs 120.3 ± 16.1; P ＜ .05). Compared with the standard TEVAR, TEVAR + RBS was associated with a lower incidence of SIDR (0% vs 2.9%; P = .033) and less secondary intervention (3.9% vs 9.3%; P = .040). Placement of the RBS significantly expanded the true lumen at the level of the descending aorta with the narrowest true lumen and at the level of the distal end of the stent graft.

CONCLUSIONS

The mismatch between the distal diameter of the stent graft and the diameter of the compressed true lumen seems to be the major factor in the occurrence of SIDR. Placement of an RBS, as an adjunctive technique to TEVAR, could reduce the incidence of SIDR. On the basis of early- to midterm observations, RBSs may improve morphological remodeling of the dissected aorta at certain levels.

Aortoesophageal fistula secondary to thoracic endovascular aortic repair of a descending aortic aneurysm rupture

PURPOSE

We present the case of a patient who developed an aortoesophageal fistula (AEF) 4 years after thoracic endovascular aortic repair (TEVAR) of a descending thoracic aortic aneurysm rupture.

CASE REPORT

A 60-year-old female patient underwent emergency stent graft placement in December 2006 because of rupture of a distal descending aortic aneurysm. The patient was discharged uneventfully. Four years later, the patient was readmitted because of recurrent hematemesis, weight loss, and malaise. A computed tomography scan and an upper gastrointestinal system (GIS) endoscopy examination revealed an AEF located at the midportion of the esophagus and at the caudal end of the stent graft. An emergency stent graft was re-replaced into the previous graft. The patient died from hemorrhagic shock due to massive GIS bleeding while she was being prepared for secondary major esophageal surgery.

CONCLUSION

AEF is a catastrophic complication of TEVAR. Conservative treatment is often associated with fatal results. If possible, these patients should be treated with secondary major surgical procedures.

Secondary surgical procedures after endovascular stent grafting of the thoracic aorta: successful approaches to a challenging clinical problem

OBJECTIVE

To evaluate the results of open surgical repair for complications after endovascular thoracic aorta stenting.

METHODS

A total of 14 patients (8 male, mean age 59.8 +/- 14.8 years) underwent conventional surgical therapy at our institution over a 5-year period after previous thoracic aortic stent implantation. The indications for surgery, intraoperative strategy, and perioperative and follow-up results were analyzed.

RESULTS

The indication for stent implantation was type B aortic dissection in 10 patients, expanding degenerative thoracic aneurysm in 3 patients, and pseudoaneurysm in 1 patient. The median interval to conventional surgery after stent implantation was 4.5 months (range 0.1-49 months). The indication for surgery was persistent type I endoleak with progressive aneurysm enlargement in 7 patients, aortoesophageal fistula in 2 patients, retrograde type A dissection in 2 patients, infection of the endoprosthesis in 2 patients, and aortic valve insufficiency caused by perforation of noncoronary and right coronary cusps in 1 patient. The endograft had to be removed in 9 (64%) patients, and 5 (36%) patients required replacement of the thoracoabdominal aorta. In-hospital mortality was 7% (1 patient). No patients had a postoperative stroke or paraparesis. Eleven (79%) patients are alive after a mean follow-up of 13.5 +/- 10.1 months (range 1-36 months).

CONCLUSIONS

Secondary surgical procedures after stenting of the thoracic aorta can be performed with very good results, despite the challenging clinical scenarios. Identification of successful surgical strategies for this difficult clinical problem is important in the era of increasing endovascular therapy.

Descending thoracic aortic dissections

Type B dissection has traditionally been managed medically if uncomplicated and surgically if associated with complications. This practice has resulted in most centers reporting significant morbidity and mortality if open repair is required. In the setting of malperfusion, operative repair has been conjoined with fenestration or visceral stenting to improve outcomes. Endovascular stent grafts seem to offer an attractive alternative in the acute complicated type B dissection, with reduced mortality and morbidity, particularly paralysis, compared with open repair. It is reasonable to consider endovascular stent grafts as another tool in managing dissection, but to recognize that open surgical repair still plays an important role, and that the data that define indications and outcomes are still emerging.

Intimal dehiscence during endovascular treatment of thoracic aortic dissection

Endovascular treatment of thoracic aortic pathology has become a valuable alternative therapeutic option to open surgery, however complications both during implantation and the postoperative period may occur. In this case report we present an intimal dehiscence during endovascular procedure. Diagnosis was made by transoesophageal echocardiography.