Treatment Of Complex Aortic Pathologies Research Articles

Staged total exclusion of the aorta for chronic type B aortic dissection

Hybrid techniques using extra-anatomic bypass of critical aortic branches to enable endovascular treatment of complex aortic pathology have been previously described. A staged endograft repair of a complex, chronic Stanford type B aortic dissection with aneurysmal degeneration is reported in a 50-year-old man. The aneurysmal portion of the dissection extended from the distal arch to both common iliac arteries and was covered with an endograft from the ascending aorta to both external iliac arteries. Aortic arch branches, visceral, and renal arteries were bypassed using open technique. The patient had no neurologic complications. This case report illustrates the feasibility of the hybrid technique in selected high-risk patients when confronted with complex aortic pathology.

Complications after stenting the thoracic aorta: can we treat them all?

Objectives: Hybrid procedures including thoracic endovascular aortic repair (TEVAR) for surgical treatment of complex aortic pathologies are booming. Yet, there are few reports on complications as well as on surgical options to treat them.

Treatment of complex disease of the thoracic aorta: the frozen elephant trunk technique with the E-vita open prosthesis☆

The treatment of complex aortic pathologies of the thoracic aorta remains a challenging issue in aortic surgery. The most recent development of the classic elephant trunk technique, the 'frozen elephant trunk' technique, represents the combination of an endovascular approach with a conventional surgical treatment for a hybrid approach. Between January 2007 and July 2008, 34 patients were operated on for complex pathologies of the thoracic aorta using the frozen elephant trunk technique. There were 29 males (85.3%) and the mean age of 61.7+/-9.6 years. The majority of patients (n=18, 52%) presented type A chronic dissection, 7 (21%) patients had chronic aneurysm of distal aortic arch and 7 (21%) type B aortic dissection associated with ascending aorta/aortic arch aneurysm. There were two (6%) cases of acute aortic dissection. Nineteen patients (56%) underwent previous cardiovascular operations. The overall in-hospital mortality was 6% (two patients). No patient developed postoperative stroke. Ischemic spinal cord injury occurred in three cases (9%) (two paraparesis, one paraplegia). There were five cases (15%) of renal failure (dialysis) and four patients (12%) had pulmonary complications with prolonged mechanical ventilation. Four patients (12%) needed rethoracotomy for surgical bleeding. Six patients (18%) required extension of the descending thoracic aorta repair with endovascular treatment for persistent perfusion of the dilated false lumen. The frozen elephant trunk technique with the new E-vita open prosthesis combines surgical and interventional technologies and represents a feasible and efficient option in the treatment of complex aortic pathologies. Strict monitoring of the patient has to be carried out in order to detect possible evolution of the aortic lesion, which can require prompt treatment. However, long-term follow-up is required.

The frozen elephant trunk: An interesting hybrid endovascular-surgical technique to treat complex pathologies of the thoracic aorta

The treatment of complex aortic pathologies involving the ascending aorta, the aortic arch, and the descending aorta remains a challenging issue in aortic surgery. The frozen elephant trunk procedure effectively combines surgical and interventional technologies in the treatment of extensive aortic aneurysms and dissections. We present two patients with complex aortic lesions involving all three segments of the thoracic aorta. The device used in our series is the new E-vita open hybrid prosthesis consisting of a proximal woven polyester tube and a distal self-expandable nitinol stent graft, which can be delivered antegrade into the descending aorta.

Hybrid Treatment for Complex Aortic Problems Combining Surgery and Stenting in the Integrated Operating Theater

Conventional surgical treatment of complex aortic pathologies involving several thoracoabdominal aortic segments necessitates extended incisions or subsequent surgeries, resulting in significant mortality and morbidity rates. The combination of surgery and simultaneous stenting in the operating theater may reduce the surgical trauma. A total of nine patients (62 +/- 10 years, range 44-70) underwent a combined surgical and endovascular treatment of thoracic or thoracoabdominal aortic aneurysms or chronic dissection. Five patients were treated with viscero-renal artery translocation followed by transfemoral stenting of the entire thoracoabdominal aorta. Two patients underwent debranching of the supraaortic vessels followed by immediate transfemoral stenting of the aortic arch, and two patients with a history of an ascending aortic aneurysm repair were treated with open surgical debranching of the supraaortic trunks and repair of the ascending aorta and aortic arch with elephant trunk technique. Preoperatively, magnetic resonance imaging was used to check supraaortic and intracranial vessels as well as the completeness of the Circle of Willisi prior to arch stenting and/or supraaortic vessel surgery. Cerebrospinal fluid drainage and induced mild hypertension have been used for one-step thoracoabdominal aortic stenting. Thirty-day mortality rate and incidence of paraplegia was 0%. There was a single reversible perioperative stroke after aortic arch stenting. One patient required temporary renal replacement therapy using continuous arterio-venous hemofiltration. There was one early reoperation at the superior mesenteric artery after viscero-renal translocation. Four type I endoleaks occurred in three patients requiring two interventions. All patients have been discharged to home. The innovative combination of simultaneous conventional surgery and stenting reduces the operative burden for patients with complex aortic pathologies involving several segments of the thoracic and thoracoabdominal aorta. Arch debranching and viscero-renal artery translocation may avoid the use of thoracoabdominal incisions, cardiopulmonary bypass techniques, deep hypothermia, and circulatory arrest.

Suprarenal aortic clamping and reperfusion decreases medullary and cortical blood flow by decreased endogenous renal nitric oxide and PGE2 synthesis

This study examined the hypothesis that clamping the aorta above the superior mesenteric artery (SMA) followed by suprarenal aortic clamping and reperfusion (SRACR) decreases microvascular blood flow by loss of endogenous medullary and cortical nitric oxide (NO) and prostaglandin (PG) E(2) synthesis. Anesthetized male Sprague-Dawley rats (350 g) had either microdialysis probes or laser Doppler fibers inserted into the renal cortex to a depth of 2 mm and into the renal medulla at 4 mm. Laser Doppler blood flow was continuously monitored (data reported as percentage of change compared to basal), and the microdialysis probes were connected to a syringe pump and perfused in vivo at 3 microL/min with lactated Ringer solution. Dialysate fluid was collected at basal time zero, following 30 minutes of suprarenal aortic clamping (ischemia) followed by 60 minutes of reperfusion and compared to a sham operation. Both groups were treated with saline carrier, indomethacin (INDO) (10 mg/kg, a cyclooxygenase [COX] inhibitor), N(G)-nitro-L-arginine methyl ester (L-NAME) (20 mg/kg, a NO synthase [NOS] inhibitor), or L-arginine (200 mg/kg, an NO precursor). Dialysate was analyzed for total NO (muM) and PGE(2) (pg/mL) synthesis. The renal cortex and medulla were analyzed for inducible NOS (iNOS) and COX-2 content by Western blot. All data are reported as mean +/- SEM, N > 5 and analyzed by analysis of variance. SRACR caused a marked decrease in medullary and cortical blood flow with a concomitant decrease in endogenous medullary and cortical NO synthesis. Treatment with L-NAME further decreased blood flow and NO synthesis in the medulla and cortex. L-Arginine restored medullary and cortical NO synthesis and blood flow in the cortex but not the medulla. SRACR did not alter renal medullary or cortical PGE(2); however, addition of INDO, COX inhibitor, caused a concomitant decrease in medullary and cortical PGE(2) synthesis and blood flow. NO is an important endogenous renal vasodilator that, when maintained can help preserve cortical blood flow following SRACR. These data also suggest that avoidance of COX-2 inhibitors can help maintain endogenous renal cortical and medullary PGE(2) synthesis and thus contribute to maintaining normal blood flow. This study is the first to combine in vivo physiologic assays to simultaneously identify clinically relevant intrarenal vasodilators (cortical and medullary) that are required to maintain microvascular blood flow. Identification of endogenous renal cortical and medullary vasodilators responsible for maintaining renal microvascular blood flow will allow development of treatment strategies to preserve these vasodilators following SRACR. Successful preservation of endogenous intrarenal vasodilators will help maintain renal microvascular blood flow and renal function in the treatment of complex aortic pathology that requires SRACR.