Risk of replacement of descending aorta with a standardized left heart bypass technique

Neuromonitoring during descending aorta procedures

Thoraco-abdominal aneurysm (TAA) repair carries a significant risk of spinal cord infarction. The latter results from irreversible changes in the spinal cord arterial network, e.g., sacrifice of the segmental arteries. Intra-operative neurophysiology with somatosensory and especially motor evoked potential (SEP and MEP respectively) monitoring, has emerged as an effective tool to assess the efficiency of the collateral blood flow, detect reversible spinal cord ischemia and guide the peri-operative multidisciplinary management to prevent postoperative paraplegia. The main roles of such monitoring include diagnosis of spinal cord vs peripheral limb ischemia, titration of mean arterial pressure during aortic clamping, the guidance of selective re-implantation of critical segmental arteries, and management of hemodynamics in the immediate postoperative period. In addition, manipulation of the aortic arch and proximal descending aorta, adds the risk of cerebral infarction from both low flow state and/or thromboembolic events. As such, EEG monitoring may be a useful add-on for either assessment of the efficiency of cerebral cooling as a neuroprotective method and/or for detection and treatment of reversible cerebral ischemia. This chapter presents the multimodality approach to open TAA monitoring as a versatile tool for the prevention of devastating postoperative neurologic deficits.

Early and mid-term results of endovascular treatment of thoracic aorta diseases: a single-center experience

We conducted an analysis to assess early and mid-term outcomes of patients after thoracic endovascular aortic repair (TEVAR) for type B thoracic aorta dissection, descending thoracic aneurysm, or traumatic aortic transection. From January 2016 through December 2018, twenty-seven patients (23 male, 4 female, mean age of 57 years) affected by type B dissection (n = 13 [48.2%]), thoracic aneurysm (n = 9 [33.3%]), and post-traumatic aortic isthmus rupture (n = 5 [18.5%]) were treated using TEVAR with and without left subclavian artery revascularization. All procedures were performed in a hybrid operating room using general (n = 12) or regional (n = 15) anesthesia. A combined brachial artery and bilateral femoral artery access was used in all patients. To achieve adequate proximal thoracic aorta landing zone length, coverage of the left subclavian artery with proximal endovascular plug occlusion was performed in 17 patients (62.9%); including 4 patients undergoing carotid-subclavian artery bypass before TEVAR stent-graft deployment. Primary procedural success rate was 96.3%; 1 patient had a Type Ib endoleak that was treated by distal stent graft extension. Four adverse outcomes occurred in the immediate postoperative period, including 2 cases of left upper arm acute ischemia (7.4%), ischemic stroke (3.7%), and asymptomatic iliac artery dissection (3.7%). During a mean follow-up of 18 months, no graft-related deaths or endoleak occurred. One patient developed symptomatic subclavian steal syndrome 1 month after operation and underwent a left carotid-subclavian artery bypass with symptom resolution. One patient died 6 months after TEVAR due to neoplasm. Our experience indicates TEVAR is a safe and less invasive alternative to open surgery for a spectrum of thoracic aorta diseases, especially for urgent conditions and in patients with high-risk surgical comorbidities.

The top 100 manuscripts in emergency cardiac surgery. Potential role in cardiothoracic training. A bibliometric analysis

Background

Emergency Cardiac Surgery (ECS) is a component of cardiothoracic training. Citations are considered to represent a papers influence. Bibliometric analyses allow us to identify the most influential work, and future research. We aim to highlight the key research themes within ECS and determine their potential impact on cardiothoracic training.

Methods

Thomas Reuters Web of Science was searched using terms [Emergency AND Card* AND Surg*]. Results were ranked by citation and reviewed by a panel of cardiac surgeons to identify the top 100 cited papers relevant to ECS. Papers were analysed by topic, journal and impact. Regression analysis was used to determine a link between impact factor and scientific impact.

Results

3823 papers were identified. Median citations for the top 100 was 88. The paper with the highest impact was by Nashef et al. focusing on the use of EuroSCORE (2043 citations). The Annals of Thoracic Surgery published most papers (n = 18:1778 citations). The European Journal of Cardiothoracic Surgery coveted the most citations (n = 2649). The USA published most papers (n = 55).The most ubiquitous topics were; risk stratification, circulatory support and aortic surgery. A positive relationship between journal impact fact and the scientific impact of manuscripts in ECS (P = 0.043) was deduced.

Conclusion

This study is the first of its kind and identified the papers which are likely to the contribute most to training and understanding of ECS. A papers influence is partially determined by journal impact factor. Bibliometric analysis is a potent tool to identify surgical training needs.

Bypass Techniques for Descending Thoracic Aortic Surgery

The conduct of partial left heart bypass or partial car diopulmonary bypass (CPB) during surgery involving the descending thoracic aorta or thoracoabdominal aorta is one of the most unappreciated and misunder stood extracorporeal circulation procedures in cardio vascular surgery. It is different from conventional CPB, and although some uninitiated practitioners consider it simpler, it is in fact more complicated than conven tional CPB and involves different concepts. It requires expertise and skill in regulating the flow, pressure, and oxygenation of blood going to both the proximal and distal parts of the body and management of the special bypass or shunt procedures used, specialized monitor ing, and knowledge about the protection and preserva tion of organs both proximal and distal to the aortic clamping. It demands exquisite communication and un derstanding of the unique problems faced by the sur geon, anesthesiologist, and perfusionist.

Complications after Endovascular Treatment of Thoracic Aortic Aneurysms

Purpose:

To retrospectively determine the value of stent-graft repair of descending thoracic aortic aneurysms by analyzing the results and complications.

Methods:

From May 1997 to July 2002, 45 patients (33 men; mean age 69 years, range 31–88) received endovascular treatment for thoracic aortic aneurysms. In 11 patients, emergency treatment was necessary for a contained rupture. The medical records of these patients were reviewed to gather data on the procedures, immediate results, complications, mortality, and survival in follow-up.

Results:

In all cases, the stent-grafts were successfully implanted. In 15 (33%) cases, the subclavian artery was covered by the stent-graft without complications. There was no paraparesis/paraplegia; 2 (4.4%) patients suffered a stroke intraoperatively. The in-hospital mortality was 2.2% (n = 1); 3 (6.7%) patients died within 30 days. Primary endoleaks occurred in 8 (17.8%) cases. Procedural success (technical success without endoleak or death) was 80% (93.3% after primary endoleak repair). During follow-up, 2 (4.4%) secondary endoleaks developed. All endoleaks were treated successfully or sealed spontaneously (n = 2). At a mean 24-month follow-up (range 1–62), 84% of patients were alive.

Conclusions:

The endovascular treatment of thoracic aortic aneurysms appears to be safe and effective, with lower morbidity and mortality than in conventional open operations. For these reasons, endovascular treatment should be administered whenever possible.

Endovascular Repair for Acute Rupture of the Descending Thoracic Aorta

Purpose:

To report the endovascular treatment of acute descending thoracic aortic rupture as an alternative to open surgery in high-risk patients.

Methods:

Between November 1999 and April 2001, 10 patients (7 men; median age 75 years) underwent endovascular stent-grafting of the descending thoracic aorta for acute rupture from an aneurysm (n = 7) or blunt trauma (n = 3). All patients were evaluated as high operative risk. The aortic rupture was associated with isolated mediastinal hematomas (n = 7), left hemothorax (n = 2), or aortobronchial fistula (n = 1). The Excluder Thoracic Endoprosthesis was used predominantly.

Results:

The mean interval to the endovascular repair was 45.3 ± 28.4 hours. All stent-grafts were successfully deployed. Two patients required common iliac artery access, and 2 needed covered stents for iatrogenic iliac artery rupture. There was 1 postoperative death (myocardial infarction) and no renal failure, neurological complications, embolization, stent-graft migration, or perigraft leak. One patient died 4 months later from an unrelated cause. At a mean follow-up of 7.9 ± 5.1 months, all aneurysms and rupture sites were excluded with no evidence of endoleak or hematoma.

Conclusions:

Endoluminal treatment is a feasible technique for the management of acute rupture of the descending thoracic aorta. Long-term studies are required to assess the effectiveness and durability of this technique in comparison to open repair.

Spinal cord injury following thoracic and thoracoabdominal aortic repairs

Objective

To discuss the currently available approaches to prevent spinal cord injury during thoracic and thoracoabdominal aortic repairs.

Methods

We carried out a PubMed search up to 2013 using the Medical Subject Headings: “aortic aneurysm/surgery” and “spinal cord ischemia”; “aortic aneurysm, thoracic/surgery” and “spinal cord ischemia”; “aneurysm/surgery” and “spinal cord ischemia/cerebrospinal fluid”; “aortic aneurysm/surgery” and “paraplegia”. All 190 original articles satisfying our inclusion criteria were analyzed for incidence, predictors, and other pertinent variables related to spinal cord injury, and we compared the results in recent publications with those in earlier reports.

Results

The mean age of the 38,491 patients was 65.3 ± 4.9 years. The overall incidence of paraplegia and/or paraparesis was 7.1% ± 6.1% (range 0%–32%). The incidence of spinal cord injury before 2000, from 2001 to 2007, and 2008–2013 was 9.0% ± 6.7%, 7.0% ± 6.1%, and 5.9% ± 5.2%, respectively ( p = 0.019). Various predictors of spinal cord injury were identified, extent of disease being the most common. Modification of surgical techniques, use of adjuncts, and better understanding of spinal cord perfusion physiology were attributed to the decrease in postoperative spinal cord injury in recent years.

Conclusions

Spinal cord injury after thoracic and thoracoabdominal aortic repair poses a real challenge to cardiovascular surgeons. However, with evolving surgical strategies, identification of predictors, and use of various adjuncts over the years, the incidence of spinal cord injury after thoracic/thoracoabdominal aortic repair has declined. Embracing a multimodality approach offers a good insight into combating this grave complication.

Role of induced hypothermia in thoracoabdominal aortic aneurysm surgery

For more than 50 years, hypothermia has been used in aortic surgery as a tool for neuroprotection. Hypothermia has been introduced into thoracoabdominal aortic aneurysm (TAAA) surgery by many cardiovascular centers to protect the body's organs, including the spinal cord. Numerous publications have shown that hypothermia can prevent immediate and delayed motor dysfunction after aortic cross-clamping. Here, we reviewed the historical application of hypothermia in aortic surgery, role of hypothermia in preclinical studies, cellular and molecular mechanisms by which hypothermia confers neuroprotection, and the role of systemic and regional hypothermia in clinical protocols to reduce and/or eliminate the devastating consequences of ischemic spinal cord injury after TAAA repair.

Hybrid Approach for the Treatment of Thoracic Aortic Arch Aneurysm in a Patient With Chronic Obstructive Lung Disease and Retrosternal Adhesion

A 73-year-old woman with a history of chronic hypertension and severe chronic obstructive pulmonary disease, presented to a district general hospital with thoracic pain in a profound state of shock. She was diagnosed with cardiac tamponade, severe mitral regurgitation, and Stanford type A (Debakey type I) intramural hematoma. Her ascending aorta was of a significant size and therefore emergent repair was done to replace the ascending aorta and mitral valve. After 6 months, an increased aneurysmal size of 6.0 cm was observed in a follow up contrast-enhanced computed tomography angiography. The patient was successfully treated by a staged hybrid procedure involving initial supra-aortic reconstruction.

Uncovered stent-graft in the treatment for residual patent false lumen after surgical repair for acute type A aortic dissection

Patent false lumen after surgery for acute type A aortic dissection (AAAD) influences the outcome with increased risk of aortic rupture and visceral malperfusion. We report a case of a patient previously operated on for aortic valve repair and replacement of the ascending aorta because of AAAD, presenting at follow-up with a retrograde dissection in aortic arch, persistent patent false lumen and significative aortic enlargement. An extensive (arch and thoraco-abdominal aorta) successful repair was performed using uncovered stent grafts. We welcome discussion on the real indication of this alternative approach and advantages and disadvantages on mid-/long-term follow-up.

Albert Wojciech Adamkiewicz (1850-1921): unsung hero behind the eponymic artery

The artery of Adamkiewicz is an important radiculomedullary artery supplying the spinal cord, especially the lumbar enlargement. Anatomical knowledge of this artery is important for avoiding serious neurological complications during surgery performed in this region--for neurosurgeons and interventional radiologists treating intramedullary tumors and spinal arteriovenous malformations, traumatologists performing spinal fusions, thoracic surgeons treating aortic aneurysms, and urologists and pediatric surgeons conducting retroperitoneal dissections. However, the biography of the talented Polish pathologist Albert Adamkiewicz, after whom the landmark artery is named, has not been described adequately in the existing neurosurgical literature. The authors bring to light the historical perspective of the eponymic artery and provide a recapitulation of other significant contributions made by Adamkiewicz, mostly involving the nervous system. His research papers on the histology of neuronal tissues and neurodegenerative diseases had high scientific merit, but the discovery of the anticancer antitoxin "cancroin" and his postulation of a cancer-causing parasite he named "Coccidium sarcolytus" met with harsh criticism and eventually led to his ill fame. The biography is supplemented with a brief overview of the important surgical implications of the artery of Adamkiewicz.

Endovascular repair of the descending thoracic aorta for penetrating atherosclerotic ulcer disease

The pathological variants of acute aortic syndromes include classic dissection, intramural hematomas, and penetrating atherosclerotic ulcers (PAUs). The subject of the appropriate management and treatment of PAUs continues to expand as this disease entity is increasingly identified. The application of thoracic endografting, or thoracic endovascular aortic repair (TEVAR), to treat these acute aortic pathologies is clearly evolving and the ultimate effectiveness and durability of thoracic endografting remains to be determined as clinical experience increases. The disease pathology of PAUs and the use of endovascular stent graft placement in PAU disease are closely examined in this manuscript.

Spinal cord ischemia after endovascular repair of the descending thoracic aorta in a sheep model

OBJECTIVES

Spinal cord ischemia remains a devastating complication after thoracic aortic surgery. The aim of this study was to investigate the pathophysiology of spinal cord ischemia after thoracic aortic endografting and the role of intercostal artery blood supply for the spinal cord in a standardized animal model.

METHODS

Female merino sheep were randomized to either I, open thoracotomy with cross-clamping of the descending aorta for 50 min (n=7), II, endograft implantation (TAG, WL Gore & Ass.), (n=6) or III open thoracotomy with clipping of all intercostal arteries (n=5) . CT-angiography was used to assess completion of surgical protocol and assess the fate of intercostal arteries. Tarloy score was used for daily neurological examination for up to 7 days post-operatively. Histological cross sections of the lumbar, thoracic and cervical spinal cords were scored for ischemic damage after stained with Hematoxylin-Eosin, Klüver-Barrrera and antibodies. Exact Kruskall-Wallis-Test was used for statistical assessment (p<0.05).

RESULTS

Incidence of paraplegia was 100% in group I and 0% in group II (p=0.0004). When compared to the endovascular group, there was a higher rate of histological changes associated with spinal cord ischemia in the animals of the control group (p=0.0096). Group III animals showed no permanent neurological deficit and only 20% infarction rate (p=0.0318 compared to group I).

CONCLUSIONS

In sheep, incidence of histological and clinical ischemic injury of the spinal cord following endografting was very low. Complete thoracic aortic stent-grafting was feasible without permanent neurologic deficit. Following endovascular coverage or clipping of their origins, there is retrograde filling of the intercostal arteries which remain patent.

Hybrid procedures as a combined endovascular and open approach for pararenal and thoracoabdominal aortic pathologies

OBJECTIVES

to report our experience with hybrid vascular procedures in patients with pararenal and thoracoabdominal aortic pathologies.

METHODS

68 patients were treated for thoracoabdominal aortic pathologies between October 1999 and February 2004; 19 patients (16 men; mean age 68, range 40-79) with high risk for open thoracoabdominal repair were considered to be candidates for combined endovascular and open repair. Aortic pathologies included five thoracoabdominal Crawford I aneurysms, one postdissection expanding aneurysm, three symptomatic plaque ruptures (Crawford IV), five combined thoracic descending and infrarenal aneurysms with a healthy visceral segment, three juxtarenal or para-anastomotic aneurysms, and two patients with simultaneous open aortic arch replacement and a rendezvous maneuver for thoracic endografting. Commercially available endografts were implanted with standardized endovascular techniques after revascularization of visceral and renal arteries.

RESULTS

Technical success was 95%. One patient developed a proximal type I endoleak after chronic expanding type B dissection and currently is waiting conversion. Nine patients underwent elective, five emergency and five urgent (within 24 h) repair. 17 operations were performed simultaneously, and 2 as a staged procedure. Postoperative complications include two retroperitoneal hemorrhages, and one patient required long-term ventilation with preexisting subglottic tracheal stenosis. Thirty-day mortality was 17% (one multiple organ failure, one secondary rupture after open aortic arch repair, one myocardial infarction). Paraplegia or acute renal failure were not observed. Total survival rate was to 83% with a mean follow-up of 30 months.

CONCLUSIONS

Midterm results of combined endovascular and open procedures in the thoracoabdominal aorta are encouraging in selected high risk patients. Staged interventions may reduce morbidity.

Neurological Complications Following Endoluminal Repair of Thoracic Aortic Disease

Open surgery for thoracic aortic disease is associated with significant morbidity and the reported rates for paraplegia and stroke are 3%-19% and 6%-11%, respectively. Spinal cord ischemia and stroke have also been reported following endoluminal repair. This study reviews the incidence of paraplegia and stroke in a series of 186 patients treated with thoracic stent grafts. From July 1997 to September 2006, 186 patients (125 men) underwent endoluminal repair of thoracic aortic pathology. Mean age was 71 years (range, 17-90 years). One hundred twenty-eight patients were treated electively and 58 patients had urgent procedures. Anesthesia was epidural in 131, general in 50, and local in 5 patients. Seven patients developed paraplegia (3.8%; two urgent and five elective). All occurred in-hospital apart from one associated with severe hypotension after a myocardial infarction at 3 weeks. Four of these recovered with cerebrospinal fluid (CSF) drainage. One patient with paraplegia died and two had permanent neurological deficit. The rate of permanent paraplegia and death was 1.6%. There were seven strokes (3.8%; four urgent and three elective). Three patients made a complete recovery, one had permanent expressive dysphasia, and three died. The rate of permanent stroke and death was 2.1%. Endoluminal treatment of thoracic aortic disease is an attractive alternative to open surgery; however, there is still a risk of paraplegia and stroke. Permanent neurological deficits and death occurred in 3.7% of the patients in this series. We conclude that prompt recognition of paraplegia and immediate insertion of a CSF drain can be an effective way of recovering spinal cord function and improving the prognosis.

Spinal Cord Perfusion and Protection During Descending Thoracic and Thoracoabdominal Aortic Surgery: The Collateral Network Concept

In the last two decades, as an increasing number of patients with descending thoracic and thoracoabdominal aneurysms are being diagnosed and treated, a more sophisticated understanding of spinal cord perfusion has become important in the attempt to minimize the frequency of spinal cord injury. The synthesis of information from laboratory studies and clinical experience has led to the collateral network concept, a framework for understanding spinal cord perfusion and thereby improving spinal cord protection during treatment of aneurysmal disease of the aorta distal to the left subclavian artery. Application of principles based on the collateral network concept has resulted in falling rates of spinal cord injury, which now approach 1% in descending thoracic aneurysm resection and less than 10% in extensive thoracoabdominal resections. These accomplishments suggest that, with further investigation, routine sacrifice of segmental aortic branches can be carried out in a way that will allow surgical and endovascular therapy of extensive distal aortic aneurysms without neurologic injury.

Differentiation of spinal cord arteries and veins by time-resolved MR angiography

PURPOSE

To dynamically resolve the inlet arteries and outlet veins of the spinal cord, particularly the Adamkiewicz artery (AKA) and great anterior radiculomedullary vein (GARV), using MR angiography (MRA).

MATERIALS AND METHODS

First, conventional two-phase angiography (acquisition time = 38-55 seconds) utilizing elliptic centric k-space ordering was applied to aortic-aneurysm patients. Changes of vessel intensity were compared between two subsequent dynamic phases. Computer modeling of bolus enhancement and k-space sampling was performed to demonstrate the relation between vessel enhancement, acquisition time, and vessel diameter. Second, time-resolved (TR, or "keyhole") angiography using a reduced number of phase-encoding steps was explored in healthy volunteers and aortic-aneurysm patients using acquisition times (range = 6-8.5 seconds) shorter than the spinal cord circulation time.

RESULTS

Using two-phase angiography the AKA and GARV were covisualized in the early phase, and contrast decreased for the AKA and increased for the GARV in most (70%) but not all cases. Computer modeling showed that the arteriovenous contrast strongly depended on vessel diameter, and complete separation was only obtained with short acquisition times. Using TR MR angiography (TR-MRA), complete temporal separation of the AKA and GARV was realized in all cases (100%).

CONCLUSION

The AKA and GARV can be completely separated by TR-MRA.

Endovascular repair in management of thoracic aortic aneurysms

OBJECTIVE

Aneurysms of the thoracic aorta are still potentially life-threatening situations. The conventional operation is still associated with morbidity. Endovascular stent graft repair offers an alternative to conventional operation for management of aortic diseases. Our aim was to report our experience with endovascular stent graft repair of thoracic aortic aneurysms.

PATIENTS AND METHODS

Between November 2002 and October 2005, endovascular stent graft repair was performed in 26 patients: post-traumatic aortic aneurysm (n=4), Type B dissection (n=3) and descending thoracic aortic aneurysm (n=19). The deployed stent graft systems were Talent-Medtronic (n=14) and Excluder-Gore (n=12).

RESULTS

Successful deployment of the stent grafts in the appropriate position was achieved in all patients. There was neither hospital mortality nor paraplegia. Late and non-procedure related death occurred in only one patient (3.8%). An average of 40% shrinkage of the aneurysmal space was observed. There was no early mortality and endoleaks. The median intensive care unit and hospital stay times were 1 and 7 days (range 4-13 days), respectively. Post-operative computed tomography scans were obtained in all patients and complete thrombosis was observed in the false lumen of dissecan aneurysms (n=3) and sac of saccular aneurysms in 25 patients. Mean follow up time was 17.1+/-5.4 months.

CONCLUSIONS

Endovascular stent graft treatment for treatment of thoracic aorta aneurysm, Type B dissection and traumatic disease of the thoracic aorta is technically feasible. Although the short and mid-term results are encouraging the long term results will determine the future of this treatment.

Dislocation of a Stent-Graft Into the Aortic Arch During Endovascular Repair of a Descending Thoracic Aortic Aneurysm

A 59-year-old man showed a saccular aneurysm due to a penetrating atherosclerotic ulcer, as well as a small type B aortic dissection located in the proximal descending aorta. The lesion was treated by the implantation of a stent-graft. On release, the stent-graft dislocated into the aortic arch. Intraoperative angiogram showed free perfusion of the brachiocephalic trunk and left common carotid artery; however, an overstenting of the carotid artery was apparent. Computed tomographic scan exhibited a complete covering of the supra-aortic vessels, and conventional, open aortic arch surgery was inevitable. A partial resection of the proximal part of the stent-graft was performed.

Underlying aortic pathology and clinical health status determine success of endovascular stent-grafting for descending thoracic aortic disease

Despite advances in medical and surgical treatment, acute as well as chronic diseases of the thoracic aorta are still associated with a high mortality. For the descending thoracic aorta, endovascular stent-graft placement competes with surgical therapy for clinical outcome. From July 1999 till December 2004, a total of 84 patients (64 +/- 14 years) with aortic disease of the descending thoracic aorta were treated. Nine patients had acute (AAD) and 35 chronic aortic dissection (AD), 16 had thoracic aortic aneurysms (TAA), 21 had penetrating aortic ulcer (PAU), and 3 patients had traumatic dissection (trans). Initial clinical status was assessed using the American Society of Anesthesiologists (ASA) classification. Fifty-three patients were in class 2, 16 in class 3, 8 in class 4, and 7 in class 5. Stent-graft placement was performed in the cardiac catheterization laboratory with the patient under general anesthesia. Technical success was obtained in 81/84 patients (96%). Within 30 days, seven patients (8%) died, four of them due to aortic rupture. In 14 patients, additional stent-grafts had to be implanted due to type I endovascular leakage (n = 5) or additional entry site adding up to a total of 107 implanted stent-grafts. During a follow-up period of 21 +/- 18 months, 17 additional patients died (22%). In 10 patients, death was disease- or procedure-related (13%). This long-term mortality depended on the underlying disease and was highest in the group with TAA (45%) followed by AAD (38%) and AD (18%). Patients in ASA class 4 and 5 had a significantly worse outcome. No aortic-related death occurred among patients with PAU or traumatic transsections. Overall, there was only one transient neurological deficit. Endovascular stent-graft placement has acceptable results in the treatment of patients with disease of the descending thoracic aorta. The outcome strongly depends on the underlying aortic pathology and the clinical health status of the patients. Randomized trials are necessary in order to establish the exact value of this new therapeutic option.

Endovascular stent-graft placement for complications of acute type B aortic dissection

PURPOSE OF REVIEW

To review the concepts and current clinical results of endovascular stent-graft placement for acute complicated type B aortic dissection.

RECENT FINDINGS

The optimal treatment for patients with dissections confined to the descending aorta (Stanford type B-AD) remains a matter of debate. Usually, antihypertensive medical therapy with strict blood pressure lowering below 135/80 mm Hg represents the first choice for patients with uncomplicated type B-AD. Patients with acute complicated type B-AD remain a major therapeutic challenge because surgery of the descending aorta is still associated with high morbidity and mortality. In 1999, endovascular stent-graft placement was introduced as a novel, less invasive treatment option for patients with type B aortic dissection. Current indications include acute (contained) aortic rupture, symptomatic ischemic branch vessel involvement, early aortic expansion, or unrelenting pain. So far, few studies on stent-graft placement in patients with acute complicated aortic dissection have been published reporting an early mortality between 0 and approximately 20%.

SUMMARY

To date, there is limited experience with endovascular stent-graft placement for acute complicated type B aortic dissection demonstrating its feasibility and life-saving potential. The endovascular approach can avoid the major trauma of open surgery and should help to get patients out of the acute life-threatening phase of the disease; however, long-term results are needed to assess the durability of this treatment.

Early and Long-term Results of Replacement of the Descending Aorta

OBJECTIVES

The aim of this analysis was to evaluate our results of open surgery on the descending thoracic aorta as benchmark to define indications for endovascular treatment.

METHODS

Between January 1981 and December 2000, 115 patients underwent replacement of the descending or thoraco-abdominal aorta. Follow-up to 20 years was complete in 98%.

RESULTS

Early mortality was 19% and paraplegia rate was 7%. Surgery before 1990 and coronary artery disease were independent predictors for early mortality. Thoraco-abdominal repair and normothermia were independent predictors for paraplegia. Ten years survival rate was 63%.

CONCLUSIONS

Our results confirm that replacement of the descending aorta can be performed today with acceptable low mortality and morbidity and with consistent exclusion of the aneurysm or dissection. Long-term results of endovascular stent-grafts in the descending aorta are unclear. In our opinion endovascular stent-grafts should be reserved for high risk patients, acute dissection or acute aortic rupture.

Endovascular repair of thoracic aortic pathology with custom-made devices

BACKGROUND

Open repair of thoracic aortic aneurysms (TAAs) is fraught with high morbidity and mortality rates. The availability of endoprostheses for treating thoracic aortic pathology has not kept pace with those for treating abdominal aneurysms. Technical feasibility, durability, and safety of custom-made stent-grafts for the treatment of TAAs and dissections are evaluated.

METHODS

From July 2002 to October 2004 there were 15 patients with TAAs, intramural hematoma, or dissections treated with custom-made endografts. Grafts were deployed after brief adenosine-induced cardiac arrest. Computed tomography scans were obtained 1 month postoperatively and every 6 months thereafter. The mean follow-up period was 15 months (range, 3-31 mo).

RESULTS

The mean age of patients was 67 +/- 11 years (range, 47-81 y; 67% men, 33% women). Indications for repair included TAA (10), chronic type B dissection (3), penetrating ulcer (1), and acute dissection (1). Planned concomitant procedures included subclavian-carotid transposition (2) and aortosplenic bypass (2) to achieve adequate proximal or distal landing seal zones, respectively. The mean length of hospital stay was 8 days (range, 1-49 d). Immediate complications included 2 access-related events, 1 cerebellar infarction treated expectantly, and 1 death from a large hemispheric stroke. There were no cases of postoperative paralysis and on follow-up imaging no cases of endoleak, endograft migration, or stent fractures were found. No late deaths occurred caused by stent-graft repair or aneurysm-related causes.

CONCLUSIONS

Endoluminal exclusion of thoracic aortic aneurysms and dissections can be achieved successfully using custom-made stent-grafts. The use of specially designed devices appears to be technically feasible and durable, with acceptable morbidity and mortality rates.

Endovascular repair of the descending thoracic aorta: evidence for the change in clinical practice

The purpose was to review outcome data following endovascular repair of the descending thoracic aorta from reports published between 1994 and 2004. To accomplish this task, 1,518 patients underwent endovascular repair for thoracic aortic disease; 810 thoracic aortic aneurysms, 500 type B thoracic aortic dissections, and 106 traumatic ruptures. The 30-day mortality rate was 5.5% and 6% for late postoperative deaths. The primary technical success rate was 97%, with only 15 patients requiring open conversion. Neurologic deficits occurred in 29 patients. In total, 118 endoleaks were reported; 29 were restented, and the remainder required surgical intervention. Graft infection occurred in 6 cases, and migrations were detected in 10. The conclusion reached is that endovascular repair of descending thoracic aortic disease is feasible and can be achieved with low rates of perioperative morbidity and mortality. As few long-term data exist on the durability of thoracic stent grafts, lifelong surveillance remains necessary.

Usefulness of Preoperative Detection of Artery of Adamkiewicz with Dynamic Contrast-enhanced MR Angiography

PURPOSE

To prospectively evaluate the detection of the artery of Adamkiewicz at magnetic resonance (MR) angiography and the effect such detection has on outcome after surgical graft placement in a series of patients with thoracoabdominal aortic disease.

MATERIALS AND METHODS

This study had ethics committee approval, and written informed consent was obtained from all patients. Fifty patients (38 men, 12 women; age range, 47-83 years; mean age, 67.2 years) who were scheduled to undergo thoracoabdominal aortic surgery for treatment of thoracoabdominal aortic aneurysm (n = 42) or thoracoabdominal aortic dissection (n = 8) were enrolled in the study. MR angiography was performed with a 1.5-T system by using dynamic three-dimensional fast spoiled gradient-recalled acquisition in the steady state with a bolus of contrast material and saline injection (4 mL/sec). Differences in the cross-clamping time, bypass time, total surgery time, and spinal complication rate between patients in whom the artery of Adamkiewicz was identified (group A) and those in whom the artery was not identified (group B) were evaluated with chi(2) or Mann-Whitney U testing.

RESULTS

In 42 of the 50 patients (84% [group A]), at least one artery of Adamkiewicz was seen to arise from an intercostal artery. Two arteries of Adamkiewicz were identified in four of the patients (8%). The artery of Adamkiewicz could not be detected with MR angiography in eight patients (group B). The ranges of cross-clamping, bypass, and total surgery times, respectively, were 30-199 minutes (mean, 78.4 minutes +/- 39.1 [standard deviation]), 30-298 minutes (mean, 96.9 minutes +/- 60.0), and 135-665 minutes (mean, 354.9 minutes +/- 133.9) in group A and 53-124 minutes (mean, 72.8 minutes +/- 29.8), 10-124 minutes (mean, 66.0 minutes +/- 41.0), and 220-405 minutes (mean, 315.6 minutes +/- 68.8) in group B. Spinal complications occurred in two patients in group B but in none of the patients in group A (P < .001).

CONCLUSION

The artery of Adamkiewicz was detected in a large percentage of patients in whom there were no spinal complications, unlike the spinal complications that occurred in the patients in whom the artery was not detected.

Endovascular Repair of the Thoracic Aorta: Lessons Learned

BACKGROUND

Available information on outcome and best strategies for thoracic endovascular repair is somewhat limited and unclear. We sought to gain a better understanding of these issues through a retrospective review of our 8-year clinical experience in the treatment of thoracic aortic aneurysms and dissections.

METHODS

A retrospective chart review of 186 patients undergoing stent-graft repair of thoracic aortic lesions at our institution during the 92-month period ending on December 31, 2004 was performed. Patients were divided into two groups based on the indication for treatment; group A had thoracic aortic aneurysms (TAA) and group B had type B aortic dissections (TBAD). Both groups were analyzed for outcome variables including technical success, mortality, major morbidity, endoleak rate and type, secondary endovascular interventions, and long-term survival. Mean follow-up was 40 months (range, 1 to 92 months).

RESULTS

Compared to group B, group A patients were older and had a higher incidence of peripheral vascular disease and chronic obstructive pulmonary disease. Sixty percent of all patients were American Society of Anesthesiologists class III and the remainder were class IV (38.3%) and V (1.7%). The procedure was completed in 180 patients (96.7%), with all 6 failures being access-related. The average procedure time was 149 minutes (range, 72 to 405). The 30-day mortality was 4.7% (9 patients), and serious morbidity was 19.9% (37 patients). Eight patients (4.3%) developed spinal cord ischemia, 4 immediately after the procedure and 4 delayed (1 to 3 days). Total hospital length of stay averaged 6.7 days. Secondary endovascular interventions were successful in 17 patients with angiographically confirmed endoleaks (type I and III). At an average follow-up of 40 months, freedom from all-cause mortality was 62.5% in group A and 58.1% in group B.

CONCLUSIONS

Stent-graft repair for TAA and TBAD can be achieved with high technical success and comparatively low rates of morbidity and mortality. Midterm survival appears to be favorable. Further refinements in device technology and procedural techniques are needed.

Long-term results of endoluminal grafting for descending thoracic aortic aneurysms

OBJECTIVE

This paper describes the long-term results of endoluminal grafting (EG) for the treatment of descending thoracic aortic aneurysms (dTAA).

METHODS

Until July 2004, EG for dTAA has been applied in 45 cases (male/female, 29/16, 49-86 years old, mean age 67 years old). Locations included the proximal dTAA in 24 cases, and middle or distal dTAA in 21 cases. The stent-grafts (SGs) were constructed of Gianturco Z-stents covered with woven polyester grafts.

RESULTS

Deployment of the SGs was successful in 43 of 45 cases (96%) and complete thrombosis of the aneurysm was achieved in 39 cases (87%). Six minor endoleaks (13%), one migration (2%) and one conversion to surgery (2%) occurred. There was no instance of paraplegia nor hospital death. Over a mean 48 month follow-up (range 3 to 90), there were three persistent endoleaks (6%), four secondary endoleaks (8%), one breakage of wire frame (2%). Four cases were converted to open surgery due to secondary endoleak. There were two aneurysmal ruptures at the site where EG was not performed. The cumulative survival rate was 95.6 +/- 4.4% at 12 months, 85.7 +/- 5.4% at 24 months, and 82.4 +/- 6.1% at 36 and 60 months.

CONCLUSION

These results demonstrated that EG is safe and effective in selected dTAA patients. Improvements in patients selection, surgical techniques and equipment will reduce EG related complications and conversion to open repair over the course of the evaluation.

Surgical resection for lung cancer with infiltration of the thoracic aorta

OBJECTIVE

The purpose of this study was to evaluate the results of a combined resection of the thoracic aorta and primary lung cancer.

METHODS

Sixteen patients underwent thoracic aorta resection along with a left pneumonectomy (n = 6), left upper lobectomy (n = 9), or partial lung resection (n = 1), of whom 10 also received preoperative induction therapy. Cardiopulmonary bypass was used in 10 patients, and a passive shunt between the ascending aorta and the descending aorta was used in 4 patients.

RESULTS

Six postoperative major complications occurred in 5 patients, including postoperative bleeding (n = 3), intraoperative bleeding (n = 1), chylothorax (n = 1), and respiratory failure (n = 1). The postoperative morbidity rate was 31%, and the mortality rate was 12.5% (2/16). Furthermore, 4 patients died of systemic tumor relapse, and 1 patient died of intrapleural recurrence. Nine patients were alive after a median follow-up of 54 months (range, 12-199 months). The median survival time of patients with postoperative pathologic N0 disease was 31 months, whereas it was 10 months for those with pathologic N2 or N3 disease. Five-year survivals were 70% for patients with N0 disease and 16.7% for patients with N2 or N3 disease ( P = .0070).

CONCLUSIONS

Although pulmonary resection with the involved aorta might cause high surgical morbidity and mortality rates, encouraging long-term survivals were obtained in patients without mediastinal nodal involvement.

Descending Thoracic Aortic Aneurysm Repair With the Aid of Partial Cardiopulmonary Bypass: Heparin-coated Circuits Versus Nonheparin-coated Circuits

BACKGROUND

We have performed descending thoracic aortic aneurysm repairs with partial cardiopulmonary bypass, including heparin-coated circuits. The aim of this study was to evaluate (i) the impact of partial cardiopulmonary bypass on distal organ function and surgical outcomes; and (ii) the effectiveness of using heparin-coated circuits for preventing bleeding complications.

METHODS

From July 1980 to June 2004, 309 patients underwent descending thoracic aortic aneurysm repairs using partial cardiopulmonary bypass. Their mean age was 61 years (range 19-81 years). One hundred of the 309 patients underwent repair of descending thoracic aortic aneurysm with heparin-coated circuits. Blood data for renal and hepatic function were collected on the day before the operation and postoperative days.

RESULTS

The in-hospital mortality was 15%. Distal organ dysfunction included spinal cord dysfunction in 2 patients (0.7%) and renal failure necessitating hemodialysis in 15 patients (5%, 15/297: excluded 12 dialysis patients). Multivariate analyses showed that preoperative hemodialysis and emergency operation were risk factors for operative mortality and that emergency operation was a risk factor for requiring hemodialysis. Renal and hepatic function normalized by 2 weeks after surgery. There were no significant differences between the heparin-coated group and nonheparin-coated group in amounts of packed red cells, fresh frozen plasma, and platelets transfused during the procedures.

CONCLUSIONS

Our data showed that partial cardiopulmonary bypass is a safe and effective method for distal perfusion. Using this technique, descending thoracic aortic aneurysm repair can be performed with acceptable mortality and morbidity. However, the superiority of heparin-coated circuits over nonheparin-coated ones was not proved.

Endovascular treatment of thoracic aortic diseases: Combined experience from the EUROSTAR and United Kingdom Thoracic Endograft registries

PURPOSE

The objective of this study was to assess the initial and 1-year outcome of endovascular treatment of thoracic aortic aneurysms and dissections collated in the European Collaborators on Stent Graft Techniques for Thoracic Aortic Aneurysm and Dissection Repair (EUROSTAR) and the United Kingdom Thoracic Endograft registries.

METHODS

Four hundred forty-three patients underwent endovascular repair of thoracic aortic disease between September 1997 and August 2003 (EUROSTAR, 340 patients; UK, 103 patients). Patients represented 4 major disease groups: degenerative aneurysm (n = 249), aortic dissection (n = 131), false anastomotic aneurysm (n = 13), and traumatic aortic injury (n = 50).

RESULTS

Mean age in the entire study group was 63 years. Fifty-two percent of patients were deemed at high risk for open surgery because of major comorbidity. Sixty percent of patients underwent an elective procedure, and 35% required emergency treatment. Conventional indications for treatment of aortic dissection, including aortic expansion, continuous pain, rupture, or symptoms of branch occlusion constituted the basis for endograft placement in 57% of patients, whereas in 43% of patients aortic dissections were asymptomatic. Primary technical success was obtained in 87% of patients with degenerative aneurysm and in 89% with aortic dissection. Paraplegia was a postoperative complication in 4.0% of patients with degenerative aneurysm and 0.8% of patients with aortic dissection (not significant). Thirty-day mortality in the entire study group was 9.3%, with mortality rates after elective procedures of 5.3% for degenerative aneurysms and 6.5% for aortic dissection. Mortality for degenerative aneurysm after emergency repair was higher (28%; P <.0001) then after elective procedures. For aortic dissection the emergency repair rate was 12% (not significant compared with elective repair of aortic dissection, and P = .025 compared with emergency repair of degenerative aneurysm). One-year follow-up was complete in 195 patients. The outcome at 1 year was more favorable for aortic dissection than for degenerative aneurysm with regard to aortic expansion (0% vs 15%; P = .001) and late survival (90% vs 80%; P = .048). In the groups with false anastomotic aneurysm and traumatic aortic injury, 30-day mortality rates were 8% and 6%, respectively.

CONCLUSION

This multicenter experience demonstrates acceptable rates for operative mortality and paraplegia after endovascular repair of thoracic aortic disease. Outcome after 30 days and 1 year was more favorable for aortic dissection than for degenerative aneurysm. However, the durability of this technique is currently unknown, and continued use of registries should provide data from long-term follow-up.

Thoracic spondylitis from a mycotic (Streptococcus pneumoniae) aortic aneurysm: a case report

STUDY DESIGN

We report on a 54-year-old man with chronic lower back pain after recent streptococcus pneumoniae pulmonary infection, resulting in a mycotic aortic aneurysm and spondylodiscitis of the eighth vertebrae 6 months later. Successful surgical treatment and recurrence-free survival after 4 years are described.

SUMMARY OF BACKGROUND DATA

Osteomyelitis by Streptococcus pneumoniae of the spine combined with contained rupture of a mycotic aortic aneurysm into lung and spine has not been reported to date. Mycotic aneurysms with pulmonary fistulas are reported to carry a mortality rate of up to 100%. Few cases have been reported with different operative and conservative strategies.

METHODS

The mycotic aortic aneurysm was excised using extracorporeal circulation and replaced by a Dacron graft. The spondylitic section of the eighth thoracic vertebrae was radically resected, and a tricortical bone block from the iliac crest was inserted into the defect. To keep compartments separated, collagen sponges with antibiotic supplementation were used. A triple antibiotic therapy (Metronidazol 3 x 0.5 g/day, Cefotaxim 3 x 2 g/day, and Flucloxacillin 3 x 2 g/day) was prescribed for 6 weeks and changed to Clindamycin for 1 year thereafter.

RESULTS

The patient made a good recovery and is free of recurrence 4 years after surgery.

CONCLUSIONS

Lower back pain might be a projected pain. Particularly in older patients or in the presence of comorbidities resulting in an immunocompromised status, an aggressive workup may be indicated. Radical resection of inflammatory tissues, sparse use of implant material, and prolonged administration of antibiotics proved a successful strategy in this patient.

Magnetic resonance angiographic localization of the artery of Adamkiewicz for spinal cord blood supply

BACKGROUND

The purpose of this study was to determine whether the artery of Adamkiewicz (ARM) can be detected by magnetic resonance angiography and to determine the usefulness of preoperative magnetic resonance angiography evaluation of the ARM.

METHODS

Between April 2000 and December 2003, 120 patients underwent magnetic resonance angiography for detection of the ARM. The morphology of the anterior spinal artery at the ARM junction, as revealed by magnetic resonance angiography, in 99 patients in whom ARM was preoperatively detected was classified into the following three types: noncontinuation of the anterior spinal artery above the ARM junction (type A), continuation of the anterior spinal artery above and below the ARM junction (type B), and noncontinuation of the anterior spinal artery below the ARM junction (type C).

RESULTS

The ARMs were detected in 99 (83%) of 120 patients, and from a total of 110 ARMs 105 (95%) originated from intercostal arteries branching from the left side and 94 (86%) originated between Th9 and Th11. Two ARMs were found in 11 (11%) of 99 patients in whom ARMs were detected. In 107 patients, who underwent magnetic resonance angiography to reveal the morphology of the anterior spinal artery at the ARM junction, the patterns of the anterior spinal artery were type A in 59 patients (55%), type B in 21 patients (20%), type C in 3 patients (3%) and not classified in 24 patients (22%). No spinal cord injury occurred in patients in whom the ARM had been preoperatively detected.

CONCLUSIONS

Preoperative detection of the ARM is possible by magnetic resonance angiography and is very useful for reducing the incidence of ischemic injury of the spinal cord.