Subclavian Artery Perfusion Research Articles

Real-world comparative claims analysis of a novel single-branched aortic stent graft device versus thoracic endograft placement with extra-anatomic debranching/revascularization in zone 2 aortic disease

Background Thoracic endovascular aortic repair (TEVAR) involving landing zone 2 can require extra-anatomic debranching (SR-TEVAR) to ensure left subclavian artery perfusion, resulting in increased costs. A single-branch device (Thoracic Branch Endoprosthesis [TBE], WL Gore, Flagstaff, AZ) provides a total endovascular solution. Comparative cost analysis of patients undergoing zone 2 TEVAR requiring left subclavian artery preservation with TBE versus SR-TEVAR is presented. Methods A single-center retrospective cost analysis was performed for aortic diseases requiring a zone 2 landing zone (TBE vs. SR-TEVAR) from 2014 to 2019. Facility charges were collected from the universal billing form UB-04 (form CMS 1450). Results Twenty-four patients were included in each arm. There were no significant differences in the overall mean procedural charges between the two groups: TBE, $209,736 ($57,761) vs. SR-TEVAR $209,025 ($93,943), P = 0.94. TBE resulted in reduced operating room charges ($36,849 [$8750] vs. $48,073 [$10,825], P = 0.02) and reduced intensive care unit and telemetry room charges, which did not reach statistical significance (P = 0.23 and 0.12, respectively). Device/implant charges were the primary cost driver in both groups. Charges associated with TBE were significantly higher: $105,525 ($36,137) vs. $51,605 ($31,326), P > 0.01. Conclusions TBE had similar overall procedural charges despite higher device/implant-related expenses and reduced facility resource utilization (lower operating room, intensive care unit, telemetry, and pharmacy charges).

Near-wall hemodynamic changes in subclavian artery perfusion induced by retrograde inner branched thoracic endograft implantation

ObjectiveLeft subclavian artery (LSA)-branched endografts with retrograde inner branch configuration (thoracic branch endoprosthesis [TBE]) offer a complete endovascular solution when LSA preservation is required during zone 2 thoracic endovascular aortic repair. However, the hemodynamic consequences of the TBE have not been well-investigated. We compared near-wall hemodynamic parameters before and after the TBE implantation using computational fluid dynamic simulations. MethodsEleven patients who had undergone TBE implantation were included. Three-dimensional aortic arch geometries were constructed from the pre- and post-TBE implantation computed tomography images. The resulting 22 three-dimensional aortic arch geometries were then discretized into finite element meshes for computational fluid dynamic simulations. Inflow boundary conditions were prescribed using normal physiological pulsatile circulation. Outlet boundary conditions consisted of Windkessel models with previously published values. Blood flow, modeled as Newtonian fluid, simulations were performed with rigid wall assumptions using SimVascular's incompressible Navier-Stokes solver. We compared well-established hemodynamic descriptors: pressure, flow rate, time-averaged wall shear stress (TAWSS), the oscillatory shear index (OSI), and percent area with an OSI of >0.2. Data were presented on the stented portion of the LSA. ResultsTBE implantation was associated with a small decrease in peak LSA pressure (153 mm Hg; interquartile range [IQR], 151-154 mm Hg vs 159 mm Hg; IQR, 158-160 mm Hg; P = .005). No difference was observed in peak LSA flow rates before and after implantation: 40.4 cm3/ (IQR, 39.5-41.6 cm3/s) vs 41.3 cm3/s (IQR, 37.2-44.8 cm3/s; P = .59). There was a significant postimplantation increase in TAWSS (15.2 dynes/cm2 [IQR, 12.2-17.7 dynes/cm2] vs 6.2 dynes/cm2 [IQR, 5.7-10.3 dynes/cm2]; P = .003), leading to decreases in both the OSI (0.088 [IQR, 0.063 to –0.099] vs 0.1 [IQR, 0.096-0.16]; P = .03) and percentage of area with an OSI of >0.2 (10.4 [IQR, 5.8-15.8] vs 15.7 [IQR, 10.7-31.9]; P = .13). Neither LSA side branch angulation (median, 81°, IQR, 77°-109°) nor moderate compression (16%-58%) seemed to have an impact on the pressure, flow rate, TAWSS, or percentage of area with an OSI of >0.2 in the stented LSA. ConclusionsThe implantation of TBE produces modest hemodynamic disturbances that are unlikely to result in clinically relevant changes.

Safety and Effectiveness of TEVAR in Native Proximal Landing Zone 2 for Chronic Type B Aortic Dissection in Patients With Genetic Aortic Syndrome

Objectives The aim of this study is to report the safety and effectiveness of thoracic endovascular aortic repair (TEVAR) in a native proximal landing zone (PLZ) 2 for chronic type B aortic dissection (TBAD) patients with genetic aortic syndrome (GAS). Methods A retrospective review of a single center database to identify patients with GAS treated with TEVAR in native PLZ 2 for chronic TBAD and thoracic false lumen aneurysm between February 2012 and February 2018 was undertaken. Results In total, 31 patients with GAS (24 Marfan syndrome [MFS], 5 Loeys-Dietz syndrome [LDS], and 2 vascular Ehlers-Danlos syndrome [vEDS]) were treated by endovascular repair. Nineteen patients were treated by TEVAR as index procedures with 8 patients (5 females, mean age = 55, range = 36–79 years old) receiving TEVAR in native PLZ 2. Left subclavian artery (LSA) perfusion was preserved in all 8 patients: by left common carotid artery-LSA bypass in 6 patients, chimney stenting of the LSA in 1 patient, and partial coverage of LSA ostium in 1 patient. Technical success was achieved in all patients (100%). There was no 30 day mortality (0%). The 30 day morbidity (0%) was free from major complications. The median follow-up was 40 months (range = 7–79). One patient died due to non-aortic-related cause. Native PLZ 2 was free from complications in MFS patients (5/8). Two patients with LDS developed type Ia endoleak with aneurysmal progression. One patient was treated by proximal extension with a double inner branched arch stent-graft landing in the replaced ascending aorta. The other one was treated with frozen elephant trunk. Conclusion Thoracic endovascular aortic repair in native PLZ 2 was safe and effective with no early or midterm PLZ complications in patients with MFS with chronic TBAD in this limited series. Native PLZ 2 is not safe in patients with LDS and should only be used in emergencies as a bridging to open repair.

On-table fenestration of frozen elephant trunk graft to achieve aberrant subclavian artery perfusion.

On-table fenestration of frozen elephant trunk graft to achieve aberrant subclavian artery perfusion.

Surgical treatment for type Stanford A aortic dissection with Kommerell's diverticulum

Objective: To examine the outcomes of surgical treatment in patients of type Stanford A aortic dissection with Kommerell's diverticulum. Methods: From January 2009 to August 2017, patients of type Stanford A aortic dissection with Kommerell's diverticulum who underwent the Sun procedure were enrolled. Patient demographic, preoperative, intraoperative, early morbidity and mortality data were collected from medical and electronic patient records. Clinical follow-up data, including late morbidity and mortality, were obtained by telephone interview with the patient. Results: A total of 13 patients (11 males and 2 females; mean age 47 years) were included. The mean maximum diameter of Kommerell's diverticulum was (21.8±7.7) mm. The Kommerell's diverticulum was repaired by direct suture of the orifice in 3 patients, ligation of the aberrant right subclavian artery in 9 patients, and suture and ligation in 1 patient, respectively. No perioperative death occurred. One patient underwent a reexploration for bleeding. There were 2 late deaths: unknown reason in 1 patient and septic shock secondary to renal abscess in 1 patient. Reintervention was performed in one patient for a persistent type Ⅱ endoleak. Conclusions: The Sun procedure with femoral artery cannulation for cardiopulmonary bypass, unilateral carotid artery cannulation for selective cerebral perfusion and ligation of aberrant right subclavian artery on the right side of the trachea is an appropriate therapeutic strategy for patients of type Stanford A aortic dissection with Kommerell's diverticulum.

Three-step method for transesophageal echocardiography-guided implantation of the frozen elephant trunk: how to prevent spinal cord injury.

Total aortic arch replacement using the frozen elephant trunk (FET) procedure has widely spread all over the world with more sophisticated devices. However, spinal cord injury is one of the most important complications, which limits the use of FET. In our hospital, 80 patients treated with FET had no spinal cord injury. There are three key points to avoid spinal cord injury, (1) The distal end of stent graft should be positioned up to the eighth thoracic vertebrae level; (2) the time for selective left subclavian artery perfusion and distal body circulatory arrest should be shortened within 60min; and (3) mean blood pressure should be maintained above 70mmHg. Especially, Key point (1) is the most important. The level of aortic valve, which locates around the seventh thoracic vertebrae level, is an appropriate benchmark. We implanted the stent graft with the use of transesophageal echocardiography guided three-step method.

Clinical amalysis of left subclavian artery revascularization by stented trunk fenestration for acute Stanford type A aortic dissection

To summarize the results and methods of left subclavian artery revascularization by stented trunk fenestration for acute Stanford type A aortic dissection. Clinical data of 67 patients (54 male and 13 female, mean age of (50±10) years) underwent surgical treatment of left subclavian artery fenestration for acute Stanford A aortic dissection in Department of Cardiothoracic Surgery, Changhai Hospital, Second Military Medical College between September 2008 and December 2014 were analyzed retrospectively. The origin of the left subclavian artery was in the true lumen and no dissection existed near the artery's starting. There were 18 cases of Marfan's syndrome. Preoperative echocardiography showed moderate to severe aortic regurgitation in 10 cases, and mitral regurgitation in 3 cases. Electrocardiogram showed myocardial ischemia in 5 cases. Three patients had acute impaired renal function. All the patients received total arch replacement combined with stented elephant trunk implantation. Left subclavian artery revascularization was performed by stented trunk fenestration as follows: firstly, stented elephant trunk was implanted to completely cover the left subclavian artery, then part of stented trunk's polyester lining was removed which is located at the origin of left subclavian artery. Aortic root procedures included aortic valve replacement in 2 cases, Bentall procedure in 21 cases and aortic valve sparing in 44 cases. Three patients received mitral valve repair and 6 patients received coronary artery bypass grafting. The cardiopulmonary bypass time, cross-clamp time, and circulatory arrest time were (179±32) minutes, (112±25) minutes, and (26±10) minutes, respectively. The in-hospital mortality was 7.5% (5/67): 2 patients died of multiple organ failure, 1 patient died of acute renal failure and another 2 patients died of severe infection shock. Two patients required reexploration for root bleeding. Transient neurology dysfunction developed in 6 patients. Six patients received tracheotomy and prolonged ventilation due to pulmonary infection. All patients discharged from the hospital were followed up for 1 to 5 years. During long-term follow-up, the survival rate was 100% and 89.8% at 1 and 5 years, respectively. CT angiography was performed once per year after discharged. The left subclavian artery perfusion was good. No dissection or anastomosis leakage was identified in any case. Stroke and left limb ischemia did not develope. For acute Stanford type A aortic dissection whose origin of the left subclavian artery is in the true lumen and no dissection existed near the artery's starting, the left subclavian artery revascularization by stented trunk fenestration technique during total arch replacement combined with stented elephant trunk implantation is reliable and effective.

Application of Unibody Single-Branch Endografts in Stanford Type B Dissections with Primary Entry Tear Adjacent to the Left Subclavian Artery: A Computed Tomography–Based Planning Study

A custom-made unibody single-branch endograft (USBE) could provide great gains in the landing zone, while maintaining a left subclavian artery (LSA) perfusion in some patients with Stanford type B dissections (TBADs). We performed a computed tomography (CT)-based planning study to determine the proportion of TBAD patients who could benefit from this custom-made USBE and ascertained the possibility of an off-the-shelf USBE in an emergency setting. We carried out a retrospective study of TBAD patients with optimal CT scans at our center from 2007 to 2013. Patients' CT scans were analyzed using 3-dimensional reconstruction software. After generating a centerline of flow, measurements (including numerous morphologic characteristics of anatomy) were evaluated. A selected subset of patients suitable for USBE was determined. Finally, the most frequently used configurations of endografts were figured out by subgroup analysis. A total of 314 patients with optimal digital imaging communications in medicine (DICOM) data were included in our study. The main primary entry tears (MPETs) were located at 22.8 ± 17.3 and 36.3 ± 18.6 mm distal to the LSA and the left common carotid artery, respectively. Overall, 169 (54.2%) patients with MPET distal to LSA (＞20 mm) could be treated by tubular stent grafts. Of the 143 patients who had intimal tears adjacent to the LSA (≤20 mm), there were 111 (35.4%) patients who could benefit from treatment using USBE based on our selection criteria. Subgroup analysis estimated the number of graft configurations needed to treat a proportion of patients: 1 design would treat 6.7% of the population, 5 designs would treat 23.1%, 10 designs would treat 37.6%, and 20 configurations would treat 54.8% . In all, 35.4% patients with TBAD could potentially benefit from USBE. The use of off-the-shelf endografts might be possible in cases of emergency, given the evidence of recurrent configurations.

Subclavian artery cannulation provides superior outcomes in patients with acute type-A dissection: long-term results of 290 consecutive patients

The short-term results of subclavian artery cannulation (SC) for acute type-A dissection repair have been reported to be superior in regard to mortality and neurological outcomes when compared to femoral cannulation (FC). This study evaluates the long-term results of subclavian artery cannulation versus femoral cannulation for repair of acute type-A dissection with particular regard to neurological deficits, mortality and the need for re-operations. From 1992-2005, 346 patients underwent surgical repair of acute type-A dissection of which 290 patients survived the operation. SC was performed in 114 patients and FC in 176 patients. Follow-up (FU) was completed in 89.5% (n = 259) and the medium FU-period was 42 months (SC) and 69 months (FC). Endpoints were persistence of neurological-deficits, mortality, major complications and necessity for re-operations. Overall survival and disease-free survival at 5 years were significantly higher in the SC group (83% vs. 71%; p = 0.022 and 74% vs. 61%; p = 0.044). Freedom of re-operation also appeared to be higher in the SC group (89% vs. 79%; p = 0.125). During the follow-up period, 28 patients (11/114 vs. 17/176; p = 0.58) suffered from neurological deficits of which 16 patients had permanent neurological-deficits at the 5 year follow-up. Of these patients, significantly more belonged to the FC group indicating an improved neurological-outcome for the SC group (3/11 vs. 13/17; p = 0.019). This study demonstrates excellent long-term outcomes after emergency surgery for acute type-A dissection. Subclavian artery perfusion represents an excellent approach to repair acute type-A dissection. Beside a significantly reduced long-term mortality, this technique provides an improved neurological outcome and a higher disease-free survival-rate.

Reply to Kestelli et al.

because they can both determine brain oedema, resulting in temporary metabolic alterations. Regarding the possible role of femoral cannulation with retrograde perfusion, we were not really convinced that it could be responsible for postoperative brain hypometabolism unless some sort of brain hypoperfusion occurs during cooling and rewarming. Furthermore, no new ischaemic lesions due to thromboembolism were documented in the magnetic resonance study in the ASCP group, even in patients in whom the femoral artery was cannulated. As we stated in the paper, an important limitation of this study, which has to be taken into account in evaluating the results, is the lack of preoperative assessment of the brain vascularization and its possible anatomical variation. In conclusion, we would like to confirm that patients with long ASCP time developed hypometabolism of the occipital lobes more frequently, due to the lack of subclavian artery perfusion during ASCP.

Evolving Knowledge About Age and Hypothermic Circulatory Arrest in Aortic Surgery

In ascending aortic surgery, progress in surgical and perfusion technology is continuous and quiet and does not produce frequent reports of short-term success. Changes in strategy show their effects years after their implementation, and may then be recommended to the broad community to adapt therapeutic strategy and thus to improve overall outcome. An example is the report by the Berne group1 in the current issue of Circulation on the effect of age on mortality and neurological injury in patients after surgical repair with hypothermic circulatory arrest in acute and chronic proximal thoracic pathology. Traditionally, age has been associated with a higher risk for both mortality and neurological injury, as has been shown by large databases such as the International Registry of Acute Aortic Dissection (IRAD).2 As a consequence, some centers refuse surgery in elderly patients because of dismal results, especially loss of quality of life, which has emerged as one of the most important surrogates for treatment success.3 Article see p 1407 However, the aforementioned reports stem from a time when deep hypothermic circulatory arrest was used as the only adjunctive technique for brain protection. Improvements in modern surgical therapy of aortic aneurysms include several important changes: subclavian artery perfusion, heparin-coated circuits for cardiopulmonary bypass, and most important, antegrade cerebral perfusion via the subclavian artery or selective perfusion catheters of supraaortic branches. Antegrade cerebral perfusion allows operating on the aortic arch in moderate hypothermia, thus reducing the side effects of deep hypothermia (eg, coagulopathy, inflammatory reactions). Additionally, concomitant treatment of the descending thoracic aorta with an open placement of a stent graft enables even more extensive repair of pathologies of the entire thoracic aorta. Commercially available trifurcated prostheses facilitate surgical aortic arch repair …

Adequacy of brain and spinal blood supply with antegrade cerebral perfusion in a rat model

The purpose of this study was to examine whether different techniques used for antegrade cerebral perfusion could account for variation in the perfusion adequacy of the brain and spinal cord. Selected vessels were ligated in 30 rats, recreating a selection of approaches used in aortic arch surgery for patients undergoing circulatory arrest with antegrade cerebral perfusion. Filling of spinal and cerebral vessels was mapped after cannulation and perfusion with E20, gelatin/India ink, or buffered saline/India ink. Three clinical approaches were replicated: unilateral perfusion, bilateral perfusion, and bilateral perfusion with additional left subclavian artery perfusion. Filling of the spinal arteries via the common carotid arteries or the subclavian arteries alone was examined. Penetration of the marker was analyzed histologically. The control experiments achieved maximal arterial filling of both brain and spinal cord at gross and microscopic levels. Unilateral and bilateral antegrade cerebral perfusion provided comprehensive arterial filling of all cerebral vessels with all vascular markers. In contrast, only bilateral antegrade cerebral perfusion provided complete spinal cord perfusion with all markers. Unilateral antegrade cerebral perfusion with a viscous marker resulted in significantly reduced spinal cord arterial filling. Examination of the relative importance of either both common carotid arteries alone or both subclavian arteries alone, in terms of their adequacy of subsequent arterial filling of the spinal cord, showed severe impairment of spinal cord perfusion with either technique. Thus perfusion of both common carotid arteries resulted in only the proximal 30% of the spinal cord arteries being filled, whereas perfusion of both subclavian arteries resulted in only the proximal 40% of the spinal cord arteries being filled. Approaches to antegrade cerebral perfusion using the brachiocephalic and left common carotid arteries together gave good perfusion of both the brain and the spinal cord. Brachiocephalic perfusion alone gave good cerebral perfusion but showed some significant limitation in spinal cord perfusion with one vascular marker. Complete spinal cord perfusion with all markers under conditions of antegrade cerebral perfusion required some contribution from both the carotid system and the subclavian system together. Selected perfusion of either system alone was very inadequate for spinal cord perfusion.

Cerebral functions and metabolism after antegrade selective cerebral perfusion in aortic arch surgery

Antegrade selective cerebral perfusion (ASCP) represents the best method of cerebral protection during surgery of the thoracic aorta. However, brain integrity and metabolism after antegrade cerebral perfusion have not yet been investigated. We assessed cerebral positron emission tomography (PET), diffusion-weighted imaging, proton magnetic resonance spectroscopy and cognitive functions in patients undergoing either ASCP or coronary artery bypass grafting (CABG) to elucidate whether cerebral perfusion was associated with postoperative neuronal alterations, metabolic deficit or cognitive decline. Seventeen patients undergoing aortic arch surgery using ASCP with moderate hypothermia (26 degrees C) (ASCP group) and 15 patients undergoing elective on-pump CABG (CABG group) were prospectively enrolled in the study. Brain PET, diffusion-weighted imaging, proton magnetic resonance spectroscopy and neuropsychometric testing were performed preoperatively, and at 1 week and 6 months postoperatively (T1, T2 and T3, respectively). Patient data were compared for statistic analysis with a normal database made up of healthy subjects. One patient in each group was excluded because they refused postoperative evaluation. There were neither strokes nor hospital deaths. Two patients suffered from temporary neurological dysfunction (one in each group). Proton magnetic resonance spectroscopy did not reveal significant alterations in cortical N-acetyl-aspartate (NAA) content within and between the groups at T2 and T3. In the ASCP group, brain diffusion-weighted magnetic resonance showed a significant increase of the apparent diffusion coefficient values, reflecting vasogenic cerebral oedema, at T2, that disappeared at T3. Magnetic resonance detected new focal brain lesions in two CABG group patients. In seven ASCP group patients, PET scan showed glucose hypometabolism in the occipital lobes at T2, which disappeared in five patients at successive examination (T3). Significant cognitive decline was not observed in any patient. Test score changes between and within groups were not significant. There was no evidence of ischaemic brain injury after ASCP even if some degree of reversible brain oedema secondary to cardiopulmonary bypass (CPB) was present. The cognitive outcomes in patients undergoing ASCP were comparable to patients undergoing coronary artery bypass. The lack of left subclavian artery perfusion during cerebral perfusion leads to temporary glucose hypometabolism in the occipital lobes without neuronal injury.

Carotid artery cannulation in acute aortic dissection with malperfusion

Clinical Summary CASE 1. A 70-year-old man with a history of hypertension, coronary heart disease, and aortic valve defect experienced sudden thoracic pain 4 years after coronary artery bypass grafting and aortic valve replacement. Shortly after admission to our institution, he was lethargic and not responsive. A computed tomogram (CT)– angiograph of the aorta showed an extended acute aortic dissection involving supra-aortic branches and iliac arteries. The innominate artery and both carotid arteries showed severe compression of the true lumen by the false lumen (Figure 1). To avoid insufficient cerebral perfusion through the narrowed true lumen during cardiopulmonary bypass (CPB), we prepared the left common carotid artery through a separate incision on the neck and cannulated it with a 10-mm Dacron side graft. In turn, for sufficient perfusion of the rest of the body, a second arterial line was installed in the right femoral artery, which was dissection free. Both arterial lines were connected with a Y-shaped tube for arterial return from one pump. Distal aortic repair (hemiarch replacement) was performed during circulatory arrest in moderate hypothermia (28.0°C) by using unilateral cerebral perfusion through the cannulated carotid artery with a flow of about 0.8 L/min for brain protection. CASE 2. A 62-year-old man with a history of coronary heart disease and previous multiple coronary catheter interventions experienced sudden pain in the abdomen and lower extremities 4 days after the last coronary angioplasty. Both legs became pale and pulseless. A CT-angiograph showed an extended aortic dissection with massive compression of the true lumen by the false lumen in the abdominal aorta and the resulting malperfusion of the abdominal organs and lower extremities (Figure 2). Intrathoracic side-graft cannulation of the left common carotid artery allowed an antegrade perfusion of the true lumen during CPB. Aortic arch replacement with reimplantation of t h e i n nominate artery and the left common carotid artery was performed during circulatory arrest in moderate hypothermia (29.0°C), with brain protection achieved by using unilateral cerebral perfusion through the left carotid artery with a flow of about 1.0 L/min. After reinstitution of CPB, valvesparing ascending aortic replacement and coronary artery bypass grafting completed the procedure. In both cases the postoperative course was uneventful. The postoperative CT imaging showed a complete recession of the false lumen in the supra-aortic branches in case 1 and a nearly complete recession of the false lumen in the abdominal aorta in case 2 (Figures 1 and 2). Currently, about 3 years after the operation, both patients are well and have no clinical symptoms.

Antegrade Cerebral Perfusion With a Simplified Technique: Unilateral Versus Bilateral Perfusion

Selective antegrade cerebral perfusion has been introduced as a strategy of cerebral protection in operations on the aortic arch with hypothermic circulatory arrest. Several techniques of unilateral and bilateral cerebral perfusion have been described with varying results. Patients underwent either unilateral cerebral perfusion with a cannula in the right subclavian artery or bilateral cerebral perfusion, with an additional cannula in the left carotid artery. A simplified Seldinger-type technique for subclavian artery cannulation was employed. Results were analyzed with multivariable logistic regression analysis and propensity score analysis to adjust for nonrandomized treatment assignment. Of 65 patients, 17 (26%) had unilateral cerebral perfusion. Mortality was 11% (n = 7); 14% (n = 9) had a stroke. In multivariable analysis, unilateral cerebral perfusion was significantly associated with stroke (odds ratio 6.6 [1.2 to 36]). Age more than 70 years was associated with in-hospital death (odds ratio 12 [1.3 to 113]), and concomitant coronary artery bypass graft surgery was associated with adverse outcome (odds ratio 23 [1.8 to 299]). Balancing variables in a propensity score analysis, stroke remained significantly more common with unilateral brain perfusion (29% versus 0%, p = 0.045). Complications associated with subclavian artery cannulation were encountered in 1 patient (1.5%). The described cannulation technique is safe and effective. Bilateral cerebral perfusion is easily achieved and is associated with decreased stroke risk, and should be the preferred brain protection strategy.

Advantages of subclavian artery perfusion for repair of acute type A dissection.

Arterial perfusion through the right subclavian artery is proposed to avoid intraoperative malperfusion during repair of acute type A dissection. This study evaluated the clinical and neurological outcome of patients undergoing surgery of acute aortic type A dissection following subclavian arterial cannulation compared to femoral artery approach. From 1/97 to 1/03, 122 consecutive patients underwent surgery for acute type A aortic dissection. Subclavian cannulation was performed in 62 versus femoral cannulation in 60 patients. Clinical characteristics in both groups were similar. Mean age was 61 years (SD+/-14 years, 72% male) and mean follow-up was 3 years (+/-2 years). Patient outcome was assessed as the prevalence of clinical complications, especially neurological deficits, mortality at 30 days, perioperative morbidity and time of body temperature cooling and analyzed by nominal logistic regression analysis for odds ratio calculation. Arterial subclavian cannulation was successfully performed without any occurrence of malperfusion in all cases. Patients undergoing subclavian cannulation showed an odds ratio of 1.98 (95% CI 1.15-3.51; P=0.0057) for an improved neurological outcome compared to patients undergoing femoral cannulation. Re-exploration rate for postoperative bleeding was significantly reduced in the subclavian group (P<0.0001), as well as occurrence of myocardial infarction (P<0.0001) and duration for body temperature cooling (P=0.004). The 30-day mortality of patients with femoral cannulation was significantly higher compared to patients with subclavian artery cannulation (24 versus 8%; P=0.0179). Arterial perfusion through the right subclavian artery provides an excellent approach for repair of acute type A dissection with optimized arterial perfusion body perfusion and allows for antegrade cerebral perfusion during circulatory arrest. The technique is safe and results in a significantly improved clinical and especially neurological outcome.

Perfusion of dominant left subclavian artery during thoracic aortic aneurysm operation

A case of aneurysm of the descending thoracic aorta with dominant left vertebral artery and poor cross-collateral circulation is reported. We believe that in such a patient perfusion of the dominant left subclavian artery is a safe method to prevent vertebrobasilar ischemia during thoracic aortic aneurysm operation under normothermia.