Juerg Schmidli

Targeting Landing Zone 0 by Total Arch Rerouting and TEVAR: Midterm Results of a Transcontinental Registry

BACKGROUND Landing zone 0, defined as a proximal landing zone in the ascending aorta, remains the last frontier to be taken. Midterm results of total arch rerouting and thoracic endovascular aortic repair (TEVAR) extending into landing zone 0 remain to be determined. METHODS From 2003 to 2011, 66 patients (mean age, 70 years; 68% men) presenting with pathologic conditions affecting the aortic arch (atherosclerotic aneurysms [n = 48], penetrating ulcers [n = 6], type B dissections [n = 6], type B after type A dissections [n = 5], and anastomotic aneurysm [n = 1]) were treated in 5 participating centers. Of these 66 patients, only 12% would have been deemed suitable for any kind of conventional surgical repair because of multisegmental aortic disease or comorbidities. RESULTS In-hospital mortality was 9%. Retrograde type A dissection was observed in 3% of patients. The assisted type I and type III endoleak rate was 0%. Stroke was seen in 5% of patients. Permanent paraplegia was observed in 3% of those studied. Median follow-up was 25 months (8-41 months). There was 1 late type Ib endoleak, which was followed by watchful waiting. Five-year survival was 72%. Five-year aorta-related survival was 96%. No aorta-related reintervention had to be performed in the segments treated. CONCLUSIONS Midterm results of total arch rerouting and TEVAR extending into landing zone 0 are excellent in regard to aorta-related survival and freedom from aorta-related reintervention. Retrograde type A dissection, potentially related to compliance mismatch between the ascending aorta and the stent-graft, warrants further attention. Extended application of this strategy augments therapeutic options in a group of patients who are not suitable candidates for conventional therapy.

Acute Aortic Dissection Determines the Fate of Initially Untreated Aortic Segments in Marfan Syndrome

Background— The aim of the current study was to investigate incidence and causes of surgical interventions in primarily nontreated aortic segments after previous aortic repair in patients with Marfan syndrome. Methods and Results— Retrospective analysis of 86 consecutive Marfan syndrome patients fulfilling Ghent criteria that underwent 136 aortic surgeries and were followed at this institution in the past 15 years. Mean follow-up was 8.8±6.8 y. Thirty-day, 6-month, 1-year, and overall mortality was 3.5%, 5.8%, 7.0%, and 12.8%, respectively. Ninety-two percent of patients initially presented with aortic root, ascending aortic or arch lesions, whereas 8% presented with descending aortic or thoraco-abdominal lesions. Primary presentation was acute aortic dissection (AAD) in 36% (77% type A, 23% type B) and aneurismal disease in 64%. Secondary complete arch replacement had to be performed in only 6% of patients without AAD, but in 36% with AAD (P=0.0005). In patients without AAD, 11% required surgery on primarily nontreated aortic segments (5 of 6 patients experienced type B dissection during follow-up), whereas in patients after AAD, 48% underwent surgery of initially nontreated aortic segments (42% of patients with type A and 86% of those with type B dissection; P=0.0002). Conclusions— The need for surgery in primarily nontreated aortic segments is precipitated by an initial presentation with AAD. Early elective surgery is associated with low mortality and reintervention rates. Type B dissection in patients with Marfan syndrome is associated with a high need for extensive aortic repair, even if the dissection is being considered uncomplicated by conventional criteria.

Aortic neck dilatation after endovascular abdominal aortic aneurysm repair: a word of caution.

Continuing aortic neck dilatation, most probably an expression of ongoing aneurysmal wall degeneration of the infrarenal aortic segment, has been shown to seriously impair clinical results after endovascular abdominal aortic aneurysm repair. However, conflicting data on the extent and clinical relevance on this observation have recently been published. This article reviews the recent literature, summarizing our current understanding of the role of aortic neck dilatation after open surgical and endovascular abdominal aortic aneurysm repair. In addition, differences in methodology of studies on aortic neck dilatation are highlighted.

Outcome and Quality of Life After Surgical and Endovascular Treatment of Descending Aortic Lesions

BACKGROUND Thoracic endovascular aortic repair (TEVAR) represents an attractive alternative to open aortic repair (OAR). The aim of this study was to assess outcome and quality of life in patients treated either by TEVAR or OAR for diseased descending thoracic aorta. METHODS A post hoc analysis of a prospectively collected consecutive series of 136 patients presenting with surgical diseases of the descending aorta between January 2001 and December 2005 was conducted. Fourteen patients were excluded because of involvement of the ascending aorta. Assessed treatment cohorts were TEVAR (n = 52) and OAR (n = 70). Mean follow-up was 34 +/- 18 months. End points were perioperative and late mortality rates and long-term quality of life as assessed by the Short Form Health Survey (SF-36) and Hospital Anxiety and Depression Score questionnaires. RESULTS Mean age was significantly higher in TEVAR patients (69 +/- 10 years versus 62 +/- 15 years; p = 0.002). Perioperative mortality rates were 9% (OAR) and 8% (TEVAR), respectively (p = 0.254). Accordingly, cumulative long-term mortality rates were similar in both cohorts. Overall quality-of-life scores were 93 (63-110, OAR) and 83 (60-112, TEVAR), respectively. Normal quality-of-life scores range from 85 to 115. Anxiety and depression scores were not increased after open surgery. CONCLUSIONS Thoracic endovascular aortic repair and OAR both provide excellent long-term results in treatment of thoracic aortic disease. Long-term quality of life, however, is reduced after thoracic aortic repair. Interestingly, TEVAR patients did not score higher in overall quality of life despite all advantages of minimized access trauma. Similarly, anxiety and depression scores are not reduced by TEVAR, possibly reflecting a certain caution against the new technology.

Delayed volume resuscitation during initial management of ruptured abdominal aortic aneurysm

OBJECTIVE In acute traumatic bleeding, permissive arterial hypotension with delayed volume resuscitation is an established lifesaving concept as abridge to surgical control. This study investigated whether preoperatively administered volume also correlated inversely with survival after ruptured abdominal aortic aneurysm (rAAA). METHODS This retrospective study analyzed prospectively collected and validated data of a consecutive cohort of patients with rAAAs (January 2001 to December 2010). Generally, fluid resuscitation was guided clinically by the patients blood pressure and consciousness. All intravenous fluids (crystalloids, colloids, and blood products) administered before aortic clamping or endovascular sealing were abstracted from paramedic and anesthesia documentation and normalized to speed of administration (liters per hour). Logistic regression modeling, adjusted for suspected confounding covariates, was used to investigate whether total volume was independently associated with risk of death within 30 days of rAAA repair. RESULTS A total of 248 patients with rAAAs were analyzed, of whom 237 (96%) underwent open repair. A median of 0.91 L of total volume per hour (interquartile range, 0.54-1.50 L/h) had been administered preoperatively to these patients. The postoperative 30-day mortality rate was 15.3% (38 deaths). The preoperative rate of fluid infusion correlated with 30-day mortality after adjustment for confounding factors, and the association persisted robustly through sensitivity analyses: each additional liter per hour increased the odds of perioperative death by 1.57-fold (95% confidence interval, 1.06-2.33; P = .026). CONCLUSIONS Aggressive volume resuscitation of patients with rAAAs before proximal aortic control predicted an increased perioperative risk of death, which was independent of systolic blood pressure. Therefore, volume resuscitation should be delayed until surgical control of bleeding is achieved.

Deleterious outcome of No-React-treated stentless valved conduits after aortic root replacement: why were warnings ignored?

OBJECTIVE The implantation of a composite graft is the treatment of choice for patients with aortic root disease if the valve cannot be preserved and the patient is not a suitable candidate for a Ross procedure. Several years ago, the Shelhigh NR-2000C (Shelhigh, Inc, Millburn, NJ) was introduced in Europe. Being a totally biologic conduit and considering the lack of homografts, the graft seemed an ideal conduit for patients with destructive endocarditis, as well as for older patients who were not suitable candidates for oral anticoagulation. METHODS From 2001 until 2006, the Shelhigh NR-2000C stentless valved conduit was implanted in 115 patients for various aortic root pathologies. The conduit consists of a bovine pericardial straight graft with an incorporated porcine stentless valve. Aortic root repair was performed during standard cardiopulmonary bypass and mild hypothermia in the majority of patients. Deep hypothermic circulatory arrest combined with selective antegrade cerebral perfusion was used when the repair extended into the arch. RESULTS Seven patients with uncomplicated early outcome presented with unexpected sudden disastrous findings at the level of the aortic root, although 1-year follow-up computed tomographic scans were normal. Four of these patients underwent emergency operations because of desintegration of the graft, along with rupture of the aortic root. Retrospectively, the main findings were persistent fever or subfebrility over months and a halo-like enhancement on computed tomographic scans. Extensive microbiologic examinations were performed without finding a causative organism. CONCLUSION The use of the Shelhigh aortic stentless conduit can no longer be advocated, and meticulous follow-up of patients in whom this device has been implanted has to be recommended.

Basic Control of Reperfusion Effectively Protects Against Reperfusion Injury in a Realistic Rodent Model of Acute Limb Ischemia

Background— Reperfusion injury is insufficiently addressed in current clinical management of acute limb ischemia. Controlled reperfusion carries an enormous clinical potential and was tested in a new reality-driven rodent model. Methods and Results— Acute hind-limb ischemia was induced in Wistar rats and maintained for 4 hours. Unlike previous tourniquets models, femoral vessels were surgically prepared to facilitate controlled reperfusion and to prevent venous stasis. Rats were randomized into an experimental group (n=7), in which limbs were selectively perfused with a cooled isotone heparin solution at a limited flow rate before blood flow was restored, and a conventional group (n=7; uncontrolled blood reperfusion). Rats were killed 4 hours after blood reperfusion. Nonischemic limbs served as controls. Ischemia/reperfusion injury was significant in both groups; total wet-to-dry ratio was 159±44% of normal (P=0.016), whereas muscle viability and contraction force were reduced to 65±13% (P=0.016) and 45±34% (P=0.045), respectively. Controlled reperfusion, however, attenuated reperfusion injury significantly. Tissue edema was less pronounced (132±16% versus 185±42%; P=0.011) and muscle viability (74±11% versus 57±9%; P=0.004) and contraction force (68±40% versus 26±7%; P=0.045) were better preserved than after uncontrolled reperfusion. Moreover, subsequent blood circulation as assessed by laser Doppler recovered completely after controlled reperfusion but stayed durably impaired after uncontrolled reperfusion (P=0.027). Conclusions— Reperfusion injury was significantly alleviated by basic modifications of the initial reperfusion period in a new in vivo model of acute limb ischemia. With this model, systematic optimizations of according protocols may eventually translate into improved clinical management of acute limb ischemia.

Internal Carotid Artery Aneurysm with Life-Threatening Hemorrhages in a Pediatric Patient: Endovascular Treatment Options:

Purpose: To describe the management of a pediatric patient with recurrent, life-threatening nasopharyngeal hemorrhages due to a pseudoaneurysm of the internal carotid artery (ICA), most likely caused by deep neck infection following peritonsillar abscess. Case Report: An 11-year-old boy presented with lymphadenopathy of the neck, torticollis, and difficulty swallowing that had persisted for some weeks. After sneezing, the patient suffered massive recurrent nasopharyngeal hemorrhages leading to anemia. Computed tomography identified a 2times2-cm hematoma in the left parapharyngeal space; angiography revealed a saccular aneurysm (14.1times8.2 mm) of the extracranial ICA adjacent to the skull base, without ongoing hemorrhage. A bare Wallstent was initially implanted, but total exclusion was achieved only after secondary placement of a Symbiot covered stent within the bare stent. Conclusions: This case demonstrates the utility of an endovascular approach to an extracranial ICA pseudoaneurysm in a pediatric patient.

Severe structural damage of the seemingly non-diseased infrarenal aortic aneurysm neck

OBJECTIVE The success of open and endovascular repair of abdominal aortic aneurysms (AAA) is hampered by postoperative dilatation of the anatomical neck of the AAA, which is used for graft attachment. The purpose of this study was to determine whether the macroscopically non-diseased infrarenal aortic neck of AAA is histologically and biochemically altered at the time of operative repair. METHODS We harvested full-thickness aortic wall samples as longitudinal stripes spanning from AAA neck to aneurysmal sac in 22 consecutive patients undergoing open surgical AAA repair. Control tissue was obtained from five organ donors and five deceased subjects undergoing autopsy without evidence of aneurysmal disease. We assessed aortic media thickness, number of intact elastic lamellar units, media destruction, and neovascularization grade and performed immunohistochemistry for matrix metalloproteinase (MMP)-9 and phosphorylated c-Jun N-terminal kinase (p-JNK). MMP-9 and p-JNK protein expressions were quantified using Western Blots. RESULTS The median thickness of the aortic media was 1150 mum in control tissue (range, 1000-1300), 510 mum in aortic necks (250-900), and 200 mum in aortic sacs (50-500, P from nonparametric test for trend <.001). The number of intact elastic lamellar units was 33 in controls (range, 33-55), 12 in aortic necks (0-31) and three in aortic sacs (0-10, P < .001). The expression of MMP-9 and p-JNK as assessed by Western Blots (P = .007 and .061, respectively) and zymography (P for trend <.001) were up regulated in both the AAA neck and sac compared with controls. Except for p-JNK expression, differences between tissues were similar after the adjustment for age, gender, and type of sampling. CONCLUSION The seemingly non-diseased infrarenal AAA neck in patients with AAA undergoing surgical repair shows histological signs of destruction and upregulation of potential drug targets.

Predictive factors for limb occlusions after endovascular aneurysm repair

OBJECTIVE Greater flexibility and smaller sizes for introducer sheaths in the newest stent grafts increase the feasibility of endovascular aneurysm repair but raise concerns about long-term limb patency. The aim of the study was to determine the incidence of and predictive factors for limb occlusion after use of the Endurant stent graft (Medtronic Inc, Minneapolis, Minn) for abdominal aortic aneurysm. METHODS The Endurant Stent Graft Natural Selection Global Postmarket Registry (ENGAGE) prospectively included 1143 patients treated with bifurcated devices who were observed for up to 2 years. Limb occlusions were evidenced by computed tomography, angiography, or ultrasound. To predict stent graft limb occlusion, a two-step model-building technique was applied. We first identified predictors from a total of 47 covariates obtained at baseline and in the periprocedural period. Subsequently, we reduced the set of potential predictors to key factors that are clinically meaningful. To handle large numbers of covariates, we used the Classification And Regression Tree (CART) method. RESULTS Forty-two stent graft limbs occluded in 39 patients (3.4% of the patients). At 2 years, the rate of freedom from stent graft limb occlusion calculated by Kaplan-Meier plot was 97.9% (standard error [SE], 0.33%). Of the 42 occlusions, 13 (31%) were observed within 30 days and 30 (71%) within 6 months. The strongest independent predictors were distal landing zone on the external iliac artery, external iliac artery diameter ≤10 mm, and kinking. High-risk vs low-risk patients were identified according to a decision tree based on the strongest predictors. Freedom from stent graft limb occlusion was 96.1% (SE, 0.64%) in high-risk patients vs 99.6% (SE, 0.19%) in low-risk patients. CONCLUSIONS After Endurant stent grafting, the incidence of limb occlusion was low. Classifying patients as high risk vs low risk according to the algorithm used in this study may help define specific strategies to prevent limb occlusion and improve the overall results of endovascular aneurysm repair using the latest generation of stent grafts.