Peri-operative Mortality and Morbidity of Complex Abdominal Aortic Aneurysms Repair in Switzerland: A Swissvasc Report.

OBJECTIVE: Complex abdominal aortic aneurysms (cAAA) pose a clinical challenge. The aim of this study was to assess the 30 day mortality and morbidity for open aneurysm repair (OAR) and fenestrated/branched endovascular aortic repair (F/BEVAR), and the effect of hospital volume in patients with asymptomatic cAAA in Switzerland. METHODS: Retrospective, cohort study using data from Switzerland's national registry for vascular surgery, Swissvasc, including patients treated from 1 January 2019 to 31 December 2022. All patients with asymptomatic, true, non-infected cAAA were identified. Primary outcome was 30 day mortality and morbidity reported using the Clavien-Dindo classification. Outcomes were compared between OAR and F/BEVAR after propensity score weighting. RESULTS: Of the 461 patients identified, 333 underwent OAR and 128 underwent F/BEVAR for cAAA. At 30 days, overall mortality rate was 3.3% after OAR and 3.1% after F/BEVAR (p = .76). Propensity scores weighted analysis indicated similar morbidity rates for both approaches: F/BEVAR (OR 0.69, 95% CI 0.45 - 1.05, p = .055); intestinal ischaemia (1.8% after OAR, 3.1% after F/BEVAR, p = .47) and renal failure requiring dialysis (1.5% after OAR, 5.5% after F/BEVAR, p = .024) were associated with highest morbidity and mortality. Treatment specific complications with high morbidity were abdominal compartment syndrome and lower limb compartment syndrome following F/BEVAR. Overall treatment volume was low for most of the hospitals treating cAAA in Switzerland; outliers with increased mortality were identified among low volume hospitals. CONCLUSION: Comparable 30 day mortality and morbidity rates were found between OAR and F/BEVAR for cAAA in Switzerland; lack of centralisation was also highlighted. Organ specific complications driving mortality were renal failure, intestinal ischaemia, and limb ischaemia, specifically after F/BEVAR. Treatment in specialised high volume centres, alongside efforts to reduce peri procedural kidney injury and mesenteric ischaemia, offers potential to lower morbidity and mortality in elective cAAA treatment.

Practical guide of vascular ultrasound in arteriovenous fistulae.

The use of vascular ultrasound, especially with the increasing prevalence of percutaneous arteriovenous fistulas, has taken a central role as a diagnostic and therapeutic imaging procedure in vascular access creation. The current review article stresses the importance of vascular ultrasound in arteriovenous fistula, from planning to creation to maintenance. It summarises and gives practical guidance regarding sonographic criteria for vascular access procedure planning, the application of vascular ultrasound intraoperatively and during follow-up. Ultrasound education and training modalities to meet high standards of patient care in hemodialysis are presented.

Evaluation of metabolic equivalents of task (METs) in the preoperative assessment in aortic repair.

BACKGROUND: Reliable prediction of the preoperative risk is of crucial importance for patients undergoing aortic repair. In this retrospective cohort study, we evaluated the metabolic equivalent of task (MET) in the preoperative risk assessment with clinical outcome in a cohort of consecutive patients. METHODS: Retrospective analysis of prospectively collected data in a single center unit of 296 patients undergoing open or endovascular aortic repair from 2009 to 2016. The patients were divided into four anatomic main groups (infrarenal (endo: n = 94; open: n = 88), juxta- and para-renal (open n = 84), thoraco-abdominal (open n = 13) and thoracic (endo: n = 11; open: n = 6). Out of these, 276 patients had a preoperative statement of their functional capacity in metabolic units and were evaluated concerning their postoperative outcome including survival, in-hospital mortality, postoperative complications, myocardial infarction and stroke, and the need of later cardiovascular interventions. RESULTS: The median follow-up of the cohort was 10.8 months. Patients with < 4MET had a higher incidence of diabetes mellitus (p = 0.0002), peripheral arterial disease (p < 0.0001), history of smoking (p = 0.003), obesity (p = 0.03) and chronic obstructive pulmonary disease (p = 0.05). Overall in-hospital mortality was 4.4% (13 patients). There was no significant difference in the survival between patients with a functional capacity of more than 4 MET (220 patients, mean survival: 74.5 months) and patients with less than 4 MET (56 patients, mean survival: 65.4 months) (p = 0.64). The mean survival of the infrarenal cohort (n = 169) was 74.3 months with no significant differences between both MET groups (> 4 MET: 131 patients, mean survival 75.5 months; < 4 MET: 38 patients, mean survival 63.6 months. p = 0.35). The subgroup after open surgical technique with less than 4 MET had the lowest mean survival of 38.8 months. In 46 patients with > 4MET (20.9%) perioperative complications occurred compared to the group with < 4MET with 18 patients (32.1%) (p = 0.075). There were no significant differences in both groups in the late cardiovascular interventions (p = 0.91) and major events including stroke and myocardial infarction (p = 0.4) monitored during the follow up period. The risk to miss a potential need for cardiac optimization in patients > 4MET was 7%. CONCLUSION: The functional preoperative evaluation by MET in patients undergoing aortic surgery is a useful surrogate marker of perioperative performance but cannot be seen as a substitute for preoperative cardiopulmonary testing in selected individuals. Trial registration clinicaltrials.gov, registration number NCT03617601 (retrospectively registered).

Interdisciplinary approach in emergency revascularization and treatment for acute mesenteric ischemia.

BACKGROUND: Mesenteric ischemia is associated with poor outcome and high overall mortality. The aim was to analyze an interdisciplinary treatment approach of vascular and visceral specialists focusing on the in-hospital outcome and follow-up in patients with acute and acute-on-chronic mesenteric ischemia. METHODS: From 2010 until 2017, 26 consecutive patients with acute or acute on chronic mesenteric ischemia were treated by an interdisciplinary team. Data were prospectively collected and retrospectively evaluated. Throughout the initial examination, the extent of bowel resection was determined by the visceral surgeon and the appropriate mode of revascularization by the vascular surgeon. The routine follow-up included clinical examination and ultrasound- or CT-imaging for patency assessment and overall survival as primary endpoint of the study. RESULTS: Out of 26 patients, 18 (69.2%) were rendered for open repair. Ten patients (38.5%) received reconstruction of the superior mesenteric artery with an iliac-mesenteric bypass. Seven patients (26.9%) underwent thrombembolectomy of the mesenteric artery. One patient received an infra-diaphragmatic aorto-celiac-mesenteric bypass. Out of the 8 patients, who were not suitable for open revascularization, 2 patients (7.7%) were treated endovascularly and 6 (23.1%) underwent explorative laparotomy. The in-hospital mortality was 23% (n = 6). The mean survival of the revascularized group (n = 20) was 51.8 months (95% CI 39.1-64.5) compared to 15.7 months in the non-revascularized group (n = 6) (95% CI - 4.8-36.1; p = 0.08). The median follow-up was 64.6 months. Primary patency in the 16 patients after open and 2 after interventional revascularization was 100% and 89.9% in the follow-up. CONCLUSION: The interdisciplinary treatment of mesenteric ischemia improves survival if carried out in time. Hereby open revascularization measures are advantageous as they allow bowel assessment, resection, and revascularization in a one-stop fashion especially in advanced cases.

Intraoperatively self-made bovine pericardial graft for portomesenteric reconstruction in pancreatic surgery.

PURPOSE: Vascular encasement or infiltration of the portomesenteric veins can compromise resectability and local tumour control in pancreatic resections. So far, there is no consensus on how vascular reconstruction should be performed. Bovine pericardium has shown promising results, particularly in infected arterial vascular reconstructions. The aim of this study is to evaluate the feasibility and technical success of portomesenteric venous vascular reconstruction using bovine pericardium in pancreatic resections. METHODS: Retrospective analysis of portomesenteric reconstruction using bovine pericardium (patches, self-made tube grafts) in pancreatic resections between 2014 and 2019. The primary endpoint examined was the technical success rate and short-term patency of vascular reconstruction. In addition to clinical surveillance and laboratory routine testing, patency was tested with duplex scans (4 h postoperatively) and computed tomography imaging in case of an abnormal clinical course and as part of the oncological follow-up. RESULTS: In 15 surgical procedures (pancreaticoduodenectomy (12, 80%), pancreatic left resection (3, 20%)), vascular reconstruction was performed with superior mesenteric vein (6/15), portal vein (7/15) and the junction between superior mesenteric and splenic vein (2/15). Eighty percent of the reconstructions were tube grafts (12/15), and the remaining were patch plasties. In 13/15 (87%) of the cases, the vascular reconstruction was patent; in 2/15 (13%), there was one stenosis without reintervention need and one graft failure with complete thrombosis. Out of 15 patients, 4 major complications according to Clavien-Dindo classification (IIIa n = 2, 13%; IIIb n = 1, 7%; V n = 1, 7%) were documented. Latest re-imaging after surgery among the 10 patients with imaging follow-up more than 1 month postoperatively was after 6.5 months ((median, interquartile range 4-12 months), and clinical follow-up was at 6.7 months (median, 3.3-13 months)). CONCLUSION: Due to its off-the-shelf availability, portomesenteric reconstruction using bovine pericardium seems to be a feasible and safe method in pancreatic resection with vascular encasement. Xenopericardial grafts can be crafted to any size and are applicable in potentially infected environment.

Anomaly of Haughton type D left cervical aortic arch in combination with type B dissection: case report and literature review.

BACKGROUND: The anomaly of cervical aortic arch is a rare phenomenon first described by Reid in 1914 and categorized by Haughton in 1975. The left cervical aortic arch Type D consisting of an ipsilateral descending aorta and coarctation or aneurysmatic formation of the arch demonstrates a complicated form requiring surgical management. Because of its rarity and unspecific symptoms only few cases are documented with the focus on surgical management. CASE PRESENTATION: A 43-year old, asymptomatic woman presented with a mediastinal mass overlapping the aortic arch region in a routine x-ray. For verification, a computed tomography was performed and revealed incidentally a type B dissection originating from an aneurysm of a left cervical arch with a maximum diameter of 6 cm. Because of the huge diameter and the potential risk of rupture, an urgent surgical repair was planned. Surgical access was performed through median sternotomy and an additional left lateral thoracic incision through the fourth intercostal space. Simultaneously to the preparation, partial cardiopulmonary bypass was installed in the left groin. After preparation of the recurrent and phrenic nerve and the supraaortic branches, the descending aorta was clamped. Before the distal anastomosis to a straight graft, we performed a fenestration of the dissection membrane about a length of 5 cm to preserve the perfusion of both lumina. Then, the straight graft was sutured to the proximal part of descending aorta. The left axillary artery originated directly from the aneurysm and was dissected and reimplanted with a separate 8 mm sidegraft to the straight graft between the distal arch and proximal descending aorta. The patient was extubated on first postoperative day and recovered well. CONCLUSION: The left cervical aortic arch type D is a rare disease, which is prone to aneurysm formation due to abnormal flow patterns and tortuosity of the aorta. The difficulty lays in the identification of the pathology, especially in the physical examination, since a pulsating mass or cervical murmur seem to be the most specific symptoms in the majority of young, female patients. If diagnosed, surgical therapy with resection of the aneurysm and reimplantation of the axillary artery under cardiopulmonary bypass demonstrates the treatment of choice.

Off-label use of thoracic aortic endovascular stent grafts to simplify difficult resections and procedures in general thoracic surgery.

OBJECTIVES: Tumour infiltration, or gross infectious involvement of the thoracic aortic wall, poses a significant intraoperative risk for fatal bleeding and therefore could compromise adequate resection or efficient surgical management of pleural infection in a considerable amount of cases. We present 3 successful cases of off-label thoracic aortic endografting to safeguard thoracic aortic wall integrity. METHODS: After all patients received thoracic stent grafts through femoral access into the descending aorta, the first patient underwent a resection of a locally advanced squamous cell carcinoma of the left inferior lobe cT4cN0-1cM0 after neoadjuvant chemoradiation, which had infiltrated the descending aortic wall. The second case was video-assisted thoracoscopic bilateral pleural decortication for empyema with aortic ulcers of the distal thoracic aorta in a patient with pancreatic intrathoracic fistula in a necrotizing pancreatitis. The third patient was operated for a locally advanced squamous cell carcinoma of the left inferior lobe initial stage cT4 cN1-2 cM0 after neoadjuvant chemoradiation, which had broad contact to the descending aorta at the level of thoracic vertebrae 7 and 8 on a circumference of circa 180°. Regional ethics committee approval according the Swiss Federal Human Research Act was obtained according to regulations. RESULTS: Preventive stent graft placement resulted in complication-free resection and significantly minimized the risk of fatal intraoperative bleeding. Patients were thus not exposed to complications associated with aortic cross-clamping, possible prosthetic replacement and extracorporeal circulation techniques. CONCLUSIONS: In carefully selected patient populations, the resection of locally advanced tumours or infectious processes involving the aortic wall can be facilitated by thoracic endovascular aortic repair prior to resection.

The role of unfractionated heparin for the antiaggregatory effect of aspirin in patients undergoing carotid endarterectomy: Results of an observational clinical study.

The aims of the present study were to examine the influence of a low-dose unfractionated heparin regime on platelet aggregation and to additionally assess the prevalence of primary aspirin resistance in patients undergoing carotid endarterectomy. Therefore, 50 patients undergoing carotid endarterectomy were enrolled. A bolus of 3000 IU unfractionated heparin was administered 2 min before carotid cross-clamping additionally to standard antiaggregatory therapy. Haemostaseological point of care testing was performed twice, prior to surgery and 10 min after unfractionated heparin administration by the use of aggregometric and viscoelastic point of care testing. Following unfractionated heparin administration, the activated partial thromboplastin time increased significantly and clotting time in viscoelastic INTEM test was shown to be significantly prolonged. In contrast, the antiaggregatory effect of aspirin was not diminished in aggregometric ASPI test. A low-dose unfractionated heparin regime during carotid endarterectomy was therefore considered to be safe, without diminishing the antiplatelet effect of aspirin. Moreover, aggregometric point of care testing was identified to be a suitable tool for the identification of patients with primary aspirin resistance ( n = 3).

Xenopericardial self-made tube grafts in infectious vascular reconstructions: Preliminary results of an easy and ready to use surgical approach.

PURPOSE: Infections are a major setback of vascular reconstruction and associated with considerable morbidity and mortality. We evaluated retrospectively our results with self-made bovine pericardial grafts in infected vessel revascularization versus standard graft material. BASIC METHODS: Retrospective analysis of 9 patients with bovine reconstruction and 10 patients with miscellaneous grafts (vein, homograft) for vascular infections. PRINCIPAL FINDINGS: Infection-free rate of the pericardial group was 100% in 17 months. For patients after reconstructions with miscellaneous grafts, the infection-free rate was 82% in 45 months. Overall in-hospital mortality was 10.5%. There were no in-hospital deaths in the pericardial group. Graft patency of the whole cohort was 100%. The median follow up was 11.74 months. CONCLUSION: Self-made bovine pericardial tube grafts can be crafted to almost any size and adjusted to complex anatomic requirements. The use was feasible in various situations and was associated with good preliminary results concerning patency and reinfection.

Effect of Superficial Cervical Plexus Block on Baroreceptor Sensitivity in Patients Undergoing Carotid Endarterectomy.

OBJECTIVES: Regional anesthesia for patients undergoing carotid endarterectomy is associated with improved intraoperative hemodynamic stability compared with general anesthesia. The authors hypothesized that the reported advantages might be related to attenuated ipsilateral baroreflex control of blood pressure, caused by chemical denervation of the carotid bulb baroreceptor nerve fibers. DESIGN: A prospective cohort study. SETTING: Single-center university hospital. PARTICIPANTS: The study included 46 patients undergoing carotid endarterectomy using superficial cervical block. INTERVENTIONS: A noninvasive computational periprocedural measurement of baroreceptor sensitivity was performed in all patients. Two groups were formed, depending on the patients' subjective response to surgical stimulation regarding the necessity of additional intraoperative local anesthesia (LA) administration on the carotid bulb. Group A (block alone) included 23 patients who required no additional anesthesia, and group B (block + LA) consisted of 23 patients who required additional anesthesia. MEASUREMENTS AND MAIN RESULTS: Baroreceptor sensitivity showed no significant change after application of the block in both groups (group A: median [IQR], 5.19 [3.07-8.54] v 4.96 [3.1-9.07]; p = 0.20) (group B: median [IQR], 4.47 [3.36-8.09] v 4.53 [3.29-8.01]; p = 0.55). There was a significant decrease in baroreceptor sensitivity in group B after intraoperative LA administration (median [IQR], 4.53 [3.29-8.01] v 3.31 [2.26-7.31]; p = 0.04). CONCLUSIONS: Standard superficial cervical plexus block did not impair local baroreceptor function, and, therefore, it was not related to improved cerebral perfusion in awake patients undergoing carotid endarterectomy. However, direct infiltration of the carotid bulb was associated with the expected attenuation of baroreflex sensitivity.

Radiation exposure to eye lens and operator hands during endovascular procedures in hybrid operating rooms.

OBJECTIVE: The purpose of this study was to evaluate the radiation exposure of vascular surgeons' eye lens and fingers during complex endovascular procedures in modern hybrid operating rooms. METHODS: Prospective, nonrandomized multicenter study design. One hundred seventy-one consecutive patients (138 male; median age, 72.5 years [interquartile range, 65-77 years]) underwent an endovascular procedure in a hybrid operating room between March 2012 and July 2013 in two vascular centers. The dose-area product (DAP), fluoroscopy time, operating time, and amount of contrast dye were registered prospectively. For radiation dose recordings, single-use dosimeters were attached at eye level and to the ring finger of the hand next to the radiation field of the operator for each endovascular procedure. Dose recordings were evaluated by an independent institution. Before the study, precursory investigations were obtained to simulate the radiation dose to eye lens and fingers with an Alderson phantome (RSD, Long Beach, Calif). RESULTS: Interventions were classified into six treatment categories: endovascular repair of infrarenal abdominal aneurysm (n = 65), thoracic endovascular aortic repair (n = 32), branched endovascular aortic repair for thoracoabdominal aneurysms (n = 17), fenestrated endovascular aortic repair for complex abdominal aortic aneurysm, (n = 25), iliac branched device (n = 8), and peripheral interventions (n = 24). There was a significant correlation in DAP between both lens (P < .01; r = 0.55) and finger (P < .01; r = 0.56) doses. The estimated fluoroscopy time to reach a radiation threshold of 20 mSv/y was 1404.10 minutes (90% confidence limit, 1160, 1650 minutes). According to correlation of the lens dose with the DAP an estimated cumulative DAP of 932,000 mGy/m(2) (90% confidence limit, 822,000, 1,039,000) would be critical for a threshold of 20 mSv/y for the eyes. CONCLUSIONS: Radiation protection is a serious issue for vascular surgeons because most complex endovascular procedures are delivering measurable radiation to the eyes. With the correlation of the DAP obtained in standard endovascular procedures a critical threshold of 20 mSv/y to the eyes can be predicted and thus an estimate of a potential harmful exposure to the eyes can be obtained.

The role of atropine in carotid stenting of recurrent stenosis after eversion endarterectomy.

OBJECTIVE: The value of prophylactic atropine use during carotid artery stenting (CAS) in primary carotid stenosis to prevent procedural hemodynamic depression is well accepted. However, its impact in case of recurrent stenosis after eversion carotid endarterectomy (E-CEA), which is known to be associated with decreased baroreflex function due to discontinuation of the carotid sinus nerve, has not been investigated so far. METHODS: The influence of angioplasty in the carotid bulb on intraprocedural and periprocedural hemodynamic changes (heart rate [HR], systolic blood pressure [SP], and diastolic blood pressure [DP]) of 38 CAS procedures (primary stenosis group, n = 16; post-E-CEA recurrent stenosis group, n = 22) was analyzed retrospectively. A single dose of 0.5 mg of atropine was administered in all cases immediately before angioplasty. Periprocedural vasoactive management was documented. Within-group differences were analyzed by the nonparametric Friedman test with pairwise comparisons following the method of Conover. RESULTS: Intraprocedural within-group comparison between the median of the 15-minute period before angioplasty and each of three single measure points with 5-minute intervals after angioplasty showed a significant decrease in almost all measures for the primary stenosis group (HR: P = .002, .0008, .08; SP: P = .005, .01, .01; DP: P = .04, .04, .01) and the opposite for the post-E-CEA stenosis group (HR: P < .0001, <.0001, <.0001; SP: P = .04, .03, .05; DP: P = .23, .06, .005). Whereas in comparison to baseline (day of admission), patients with primary stenosis showed a significant periprocedural decrease in HR (recovery room, P < .0001; 6-24 hours, P = .0012; 25-48 hours, P = .014) and SP (recovery room, P < .0001; 6-24 hours, P < .0001; 25-48 hours, P < .0001), patients with restenosis after E-CEA revealed no significant changes with the exception of increased HR between 6 and 24 hours and decreased DP in the recovery room. CONCLUSIONS: The application of atropine during CAS for recurrent carotid stenosis after prior E-CEA might not be necessary.

Perioperative blood pressure alterations after eversion and conventional carotid endarterectomy sustain in the midterm.

OBJECTIVE: Carotid endarterectomy (CEA) is associated with a profound effect on blood pressure. The aim of this study was to evaluate 24 h ambulatory blood pressure measurement (ABPM) after eversion (E-CEA) and conventional (C-CEA) endarterectomy including a midterm follow-up. METHODS: Seventy-one patients were included in this prospective study [E-CEA (37)/C-CEA (34)]. Daytime (8 a.m. to 10 p.m.) and nighttime (10 p.m. to 8 a.m.) ABPMs were analyzed perioperatively and at midterm after a median follow-up period of 9.5 months (interquartile range (IQR) 6.4-17.8) in the E-CEA group and 11.5 months (IQR 8.3-13.6) in the C-CEA group RESULTS: Patient demographics and preoperative antihypertensive regimens were similar in the two groups. Compared with baseline, ABPM decreased on postoperative day 1 in the C-CEA group (P < 0.01) but normalized by day three. By contrast, ABPM values were unchanged on day 1 in the E-CEA group but increased above baseline on day 3 (P < 0.01). E-CEA was associated with higher ABPM on day 1 (P < 0.001 daytime, P < 0.01 nighttime) and again on day 3 (P < 0.001 daytime, P < 0.01 nighttime). The use of vasodilators was more frequent in the E-CEA group, both in the recovery room (P = 0.007) and on the ward (P = 0.004). Midterm results showed no difference of average blood pressure values, but an increased maximal blood pressure (P = 0.01 daytime) and heart rate (HR) (P = 0.006 daytime) were reached in the E-CEA group and decreased HR (P = 0.01 nighttime) in the C-CEA group. Compared with baseline [(E-CEA: median (IQR) 2 (1-3); C-CEA: median (IQR) 2 (1-3)], the number of antihypertensive medications at midterm was significantly higher in the E-CEA group [(median (IQR) 3 (2-3) vs. 2 (2-3), P = 0.002)]. In both groups, no adverse cardiovascular or cerebrovascular events during follow-up could be observed. CONCLUSION: Although the initial hypertensive effect of E-CEA diminishes during midterm follow-up, patients undergoing eversion endarterectomy keep needing more antihypertensive medications and are prone to develop higher maximal blood pressure.

Eversion carotid endarterectomy is associated with impaired postoperative hemodynamic stability compared with the conventional technique.

BACKGROUND: Carotid endarterectomy is associated with a profound effect on blood pressure. The aim of this study was to evaluate 24-hour ambulatory blood pressure measurements (ABPMs) after eversion carotid endarterectomy (E-CEA) and conventional carotid endarterectomy (C-CEA). METHODS: Seventy-one patients were included in this prospective study (E-CEA [37]/C-CEA [34]). Daytime (8 AM-10 PM) and nighttime (10 PM-8 AM) ABPMs were analyzed preoperatively and on postoperative days 1 and 3. RESULTS: Patients' demographics and preoperative antihypertensive regimens were similar in the two groups. Compared with baseline, ABPM decreased on postoperative day 1 in the C-CEA group (P < 0.01) but normalized by day 3. By contrast, ABPM values were unchanged on day 1 in the E-CEA group but increased above baseline on day 3 (P < 0.01). E-CEA was associated with higher ABPM on day 1 (daytime: P < 0.001; nighttime: P < 0.01) and again on day 3 (daytime: P < 0.001; nighttime: P < 0.01). The use of vasodilators was more frequent in the E-CEA group, both in the recovery room (P = 0.007) and on the ward (P = 0.004). CONCLUSION: E-CEA may be associated with higher postoperative blood pressure and the need for more additional antihypertensive therapy in the postoperative period compared with C-CEA.

Altered in-stent hemodynamics may cause erroneous upgrading of moderate carotid artery restenosis when evaluated by duplex ultrasound.

OBJECTIVE: To assess the influence of stent application on in-stent hemodynamics under standardized conditions. METHODS: Ovine common carotid arteries before and after stent (6 × 40 mm, sinus-Carotid-RXt, combined open-closed cell design; Optimed, Ettlingen, Germany) application were used. Plastic tubes, 10 mm in length, simulating stenosis were placed in the middle of the applied stent to induce different degrees of stenosis (moderate 57.8% and severe 76.4%). Flow velocity and dynamic compliance were, respectively, measured with ultrasound and laser scan; proximal, in-stent, and distal to the stented arterial segment (1 cm proximal and distal) in a pulsatile ex vivo circulation system. RESULTS: Stent insertion caused the in-stent peak systolic velocity to increase 22% without stenosis, 31% with moderate stenosis, and 23% with severe stenosis. Stent insertion without stenosis caused no significant increase in in-stent end-diastolic velocity (EDV) but a 17% increase with moderate stenosis. In severe stenosis, EDV was increased 56% proximal to the stenosis. Compliance was reduced threefold in the middle of the stented arterial segment where flow velocity was significantly increased. CONCLUSIONS: With or without stenosis, stent introduction caused the in-stent peak systolic velocity to become significantly elevated compared with a nonstented area. EDV was also increased by stent insertion in the case of moderate stenosis. The stent-induced compliance reduction may be causal for the increase in flow velocity since the stent-induced flow velocity elevation appeared in the stented area with low compliance. Because of altered hemodynamics caused by stent introduction when measured by duplex ultrasound, caution is prudent in concluding that carotid artery stenting is associated with a higher restenosis rate than carotid endarterectomy. Mistakenly upgrading moderate to severe restenosis could result in unnecessary reintervention. CLINICAL RELEVANCE: Clinical experience and prior studies support the supposition that restenosis after carotid artery stenting in carotid lesions displays erroneously elevated velocity when evaluated by duplex ultrasound (DUS), thus contributing to misleading interpretation of the degree of stenosis. This study, in contrast to studies of other groups, employs exactly the same conditions to measure flow with DUS in an unstented and then stented section of the carotid artery. Since DUS is the first-choice tool for carotid artery evaluation, knowledge about inexactness of the method is essential to avoid errors in treatment or follow-up decisions.

Comparison of renin and catecholamine release in patients undergoing eversion or conventional carotid endarterectomy.

OBJECTIVE: The two techniques for carotid endarterectomy (CEA)--conventional (C-CEA) and eversion (E-CEA)--have different effects on blood pressure. This study compared sympathetic activity after C-CEA and E-CEA, as measured by renin and catecholamine levels. METHODS: E-CEA (n = 40) and C-CEA (n = 34) were performed in 74 patients with high-grade carotid stenosis. The choice of technique was made at the discretion of the operating surgeon. All patients received clonidine (150 µg) preoperatively. Regional anesthesia was used. The carotid sinus nerve was transected during E-CEA and preserved during C-CEA. Renin, metanephrine, and normetanephrine levels were measured preoperatively and at 24 and 48 hours postoperatively. RESULTS: Compared with baseline, levels of renin, metanephrine, and normetanephrine decreased at 24 and 48 hours after C-CEA (P < .0001). After E-CEA, however, renin and normetanephrine levels were unchanged at 24 hours, and metanephrine levels were increased (P < .0001). At 48 hours, levels of renin (P = .04), metanephrine (P < .0001), and normetanephrine (P = .02) were increased. Compared with C-CEA, E-CEA was associated with significantly increased sympathetic activity at 24 and 48 hours (P < .0001). Although the use of vasodilators for postoperative hypertension did not differ in the postanesthesia care unit (E-CEA 35% vs C-CEA 18%, P = .12), vasodilator use on the ward was more frequent after E-CEA (60% vs 32%, P = .02). CONCLUSIONS: E-CEA appears to be associated with greater postoperative sympathetic activity and vasodilator requirements than C-CEA, findings likely related to sacrifice of the carotid sinus nerve during E-CEA but not C-CEA.

Multicenter experience on eversion versus conventional carotid endarterectomy in symptomatic carotid artery stenosis: observations from the Stent-Protected Angioplasty Versus Carotid Endarterectomy (SPACE-1) trial.

BACKGROUND AND PURPOSE: Carotid endarterectomy (CEA) is beneficial in patients with symptomatic carotid artery stenosis. However, randomized trials have not provided evidence concerning the optimal CEA technique, conventional or eversion. METHODS: The outcome of 563 patients within the surgical randomization arm of the Stent-Protected Angioplasty versus Carotid Endarterectomy in Symptomatic Patients (SPACE-1) trial was analyzed by surgical technique subgroups: eversion endarterectomy versus conventional endarterectomy with patch angioplasty. The primary end point was ipsilateral stroke or death within 30 days after surgery. Secondary outcome events included perioperative adverse events and the 2-year risk of restenosis, stroke, and death. RESULTS: Both groups were similar in terms of demographic and other baseline clinical variables. Shunt frequency was higher in the conventional CEA group (65% versus 17%; P<0.0001). The risk of ipsilateral stroke or death within 30 days after surgery was significantly greater with eversion CEA (9% versus 3%; P=0.005). There were no statistically significant differences in the rate of perioperative secondary outcome events with the exception of a significantly higher risk of intraoperative ipsilateral stroke rate in the eversion CEA group (4% versus 0.3%; P=0.0035). The 2-year risk of ipsilateral stroke occurring after 30 days was significantly higher in the conventional CEA group (2.9% versus 0%; P=0.017). CONCLUSIONS: In patients with symptomatic carotid artery stenosis, conventional CEA appears to be associated with better periprocedural neurological outcome than eversion CEA. Eversion CEA, however, may be more effective for long-term prevention of ipsilateral stroke. These findings should be interpreted with caution noting the limitations of the post hoc, nonrandomized nature of the analysis.

Changes in baroreceptor sensitivity after eversion carotid endarterectomy.

OBJECTIVE: Posteversion carotid endarterectomy hypertension has been suggested to be associated with impaired baroreceptor sensitivity (BRS), which has been identified as a factor of prognostic relevance in patients with cardiovascular disease. The aim of this prospective single-center nonrandomized study was to describe the changes of BRS in the early postoperative period after eversion carotid endarterectomy (E-CEA). METHODS: Spontaneous BRS and hemodynamic parameters such as blood pressure (BP), heart rate (HR), cardiac output (CO), and total peripheral resistance (TPR) were evaluated preoperatively as well as postoperatively after 1 and 3 days using a noninvasive sequential cross-correlation method. Additionally, any modification in vasoactive medication due to BP derangement in the postoperative period was noted. Due to non-normal distribution of BRS, HR, and TPR samples, all measured values were expressed as medians with interquartile range (IQR), and a nonparametric test (Friedman) was performed. After adjustment for multiple testing, differences were considered statistically significant when the two-tailed P value was less than .0036. RESULTS: Thirty-five patients (mean age, 71 years) with symptomatic or asymptomatic internal carotid artery stenosis were included. The BRS significantly decreased to a lower level 24 hours after surgery (4.71 ms/mm Hg [3.02-6.1]) than preoperatively (5.95 ms/mm Hg [4.68-10.86]; P < .0001), resulting in a within-patient difference of -2.46 ms/mm Hg (95% confidence interval [CI], -8.38 - -1.52). This difference (95% CI, [- 1.58 (-8.24 - -0.80)]) persisted at the 72-hour measurements (5.63 ms/mm Hg [3.23-7.69]; P = .0005). The HR, reflecting the sympathetic activity, increased 24 hours after the operation (69 bpm [61.3-77.7]) compared with preoperative values (63 bpm [57.9-73.2]; P = .005) (within-patient difference [95% CI] 3.7 [1.5-8.5]), and this increase reached significance at 72 hours (69 bpm [65.4-77.5]; P = .001) (within-patient difference [95% CI] 5.5 [2.3-8.8]). Values of systolic pressure, diastolic pressure, mean arterial pressure, CO, and TPR were not significantly different between pre- and postoperative measurements. Overall, 23 (66%) patients developed significant postoperative hypertension requiring aggressive management with additional medications. CONCLUSIONS: E-CEA might have a decreasing influence on BRS, leading to increased sympathetic activity. Investigations of the longer-term effects of impaired BRS are warranted. These findings should be interpreted with caution, noting the limitation of an absent control group.

Total vs hemi-aortic arch transposition for hybrid aortic arch repair.

OBJECTIVE: To compare the outcomes of total aortic arch transposition (TAAT) vs hemi-aortic arch transposition (HAAT) for hybrid aortic arch repair. METHODS: A systematic search was performed using PubMed between November 1998 and May 2010 by two independent observers. Studies included reporting on patients treated by TAAT or HAAT and stent grafting in a proximal landing zone 0 or 1 by Ishimaru, respectively. Further articles were identified by following MEDLINE links, by cross-referencing from the reference lists, and by following citations for these studies. Case reports and case series of less than five patients were excluded. Primary technical and initial clinical success, perioperative, and late morbidity and mortality were extracted per study and were meta-analyzed. RESULTS: Fourteen studies were included in the statistical analysis. The number of reported patients totaled 130 for TAAT/zone 0 and 131 for HAAT/zone 1. The primary technical success rate was significantly higher in zone 0 than 1 (95% vs 83%; odds ratio [OR], 4.0; 95% confidence interval [CI], 1.47-10.88; P = .0069), due to significantly higher primary type I or III endoleak rates in zone 1 (15.48% vs 3.97%; P = .0050). Reintervention rates were significantly higher in zone 1 (25.81% vs 12.00%; P = .0321). Initial clinical success rates were comparable between zone 0 and 1 (88% vs 85%; OR, 1.35; 95% CI, 0.61-3.02; P = .5354). In-hospital mortality was higher in zone 0 than 1 (8.46% vs 4.58%; P = .2212). CONCLUSION: The more invasive TAAT allows a better landing zone at the cost of higher perioperative mortality, therefore, patient selection is crucial.

The effect of eversion and conventional-patch technique in carotid surgery on postoperative hypertension.

OBJECTIVE: Postcarotid endarterectomy hypertension (HTN) is associated with neurological and cardiac complications. The purpose of this study was to assess the influence of eversion carotid endarterectomy (E-CEA) and conventional carotid endarterectomy (C-CEA) on postoperative blood pressure in the first 4 days after surgery. METHODS: Two hundred seventy-six consecutive CEAs that were performed between February 2008 and September 2009 were reviewed retrospectively with a computerized registry. After exclusion of patients with severe stroke (modified Rankin Scale of 3-5), prior contralateral and ipsilateral carotid surgery and more than 70% stenosis of the contralateral carotid artery, 201 cases remained (E-CEA group: n = 100 vs C-CEA group: n = 101) for analysis. Results in terms of systolic blood pressure, use of intravenous and oral vasodilators, alterations of the existing antihypertensive medications, and perioperative complications (neck hematoma, myocardial infarction, stroke, and death) were compared. RESULTS: Groups were similar with regard to age, sex, and cardiovascular risk factors except for a higher incidence of nicotine use (59% vs 43%; P = .02) in the C-CEA group. Patients in the C-CEA group had a significantly higher percentage of symptomatic carotid artery stenosis (54% vs 23%, respectively; P < .0001). Despite a lower preoperative (baseline) mean systolic blood pressure (130 mm Hg vs 135 mm Hg; P = .02) patients in the E-CEA group had a significantly higher mean systolic blood pressure in the postoperative course up to the day 4 after surgery (134 mm Hg vs 126 mm Hg; P < .0001) and required more frequent intravenous (28% vs 9.9%; P = .001) and oral vasodilators (54% vs 27.7%; P = .0002) compared to those in the C-CEA group. Two-thirds (14 of 21 = 66%) of patients in the E-CEA group with preoperative high blood pressure (systolic blood pressure ≥140 mm Hg and diastolic pressure ≥90 mm Hg) required vasodilators and only one-third (11 of 33 = 33%) in the C-CEA group (P = .03). Atropine use due to bradycardia was necessary after 8 cases (8%) in the C-CEA group and only after 1 case (1%) in the E-CEA group (P = .03). Furthermore, the dosage of existing antihypertensive medications was increased and/or additional medications were prescribed twofold more in the E-CEA group (33% vs 17%; P = .009). No statistically significant difference was noted in the perioperative complication rate. CONCLUSION: It is concluded that E-CEA is associated with significantly higher postoperative blood pressure that persists for at least 4 days after surgery. Patients with inadequate preoperative high blood pressure control are particularly at risk after E-CEA.