Arch repair with unilateral antegrade cerebral perfusion.

OBJECTIVE: Several antegrade cerebral perfusion techniques with differing neurological outcomes are employed for aortic arch repair. This study demonstrates the clinical results of aortic arch repair with unilateral cerebral perfusion via the right brachial artery. METHODS: Between January 1996 and March 2004, 181 patients underwent aortic arch repair via the right upper brachial artery with the use of low-flow (8-10 ml/kg per min) antegrade selective cerebral perfusion under moderate hypothermia (26 degrees C). Mean patient age was 58+/-12 years. Presenting pathologies were Stanford type A aortic dissection in 112, aneurysm of ascending and arch of aorta in 67, and isolated arch aneurysm in two patients. Ascending and/or partial arch replacement was performed in 90 patients and ascending and total arch replacement in 91 patients (including 27 with elephant trunk). In a subset of patients, renal and hepatic effects of ischemic insult were assessed. Free hemoglobin and lactate dehydrogenase levels were measured pre and postoperatively to identify hemolytic effects of brachial artery cannulation. RESULTS: Mean antegrade cerebral perfusion time was 36+/-27 min. Three patients with acute proximal dissection died due to cerebral complications. One patient had transient right hemiparesis. Total major neurological event rate was 2.2%. Brachial artery was able to carry full cardiopulmonary bypass flow with mild hemolysis. Renal and hepatic tests showed no deleterious effects of limited ischemia at moderate hypothermia. CONCLUSIONS: Arch repair with antegrade cerebral perfusion through right brachial artery has excellent neurological results, provides technical simplicity and optimal repair without time restraints, does not necessitate deep hypothermia and requires shorter CPB and operation times.     

Aortic arch and proximal supraaortic arterial repair under continuous antegrade cerebral perfusion and moderate hypothermia.

PURPOSE: In this prospective study the clinical and neurological outcome of continuous antegrade cerebral perfusion (ACP) and moderate hypothermia was evaluated in patients undergoing ascending and aortic arch repair including reconstruction of the proximal supraaortic arteries. METHODS: In 50 consecutive patients (mean age 47 yr, range 22-70) aortic arch and supraaortic arterial repair was performed: ascending aorta and aortic arch (n=34) and aortic arch and Bentall procedure (n = 16). In 12 patients the distal anastomosis was performed using the elephant trunk technique. Test-clamping of the innominate artery for 3 min was performed under EEG-monitoring followed by the same procedure for the left carotid artery. Cardiopulmonary bypass was instituted and the innominate artery replaced by a polyester graft before antegrade perfusion was carried out through the graft. While cooling to 28-30 degrees C, the left carotid artery was similarly treated with subsequent antegrade cerebral perfusion. The distal anastomosis was made at or beyond the left subclavian artery under circulatory arrest. During rewarming the innominate and carotid polyester grafts as well as the subclavian artery were anastomosed to the main graft, while antegrade cerebral perfusion was continued. RESULTS: In 46 patients antegrade cerebral perfusion was achieved with a mean volume flow of 12 ml/kg/min and a mean arterial pressure of 54 mmHg. EEG-monitoring delineated stable and symmetrical recordings. In four patients antegrade flow (mean 15 ml/kg/min) and pressure (mean 65 mmHg) had to be increased to establish baseline EEG-recordings. The mean time of circulatory arrest was 18 min.The overall hospital mortality was 6%: two patients died from cerebral infarction and one patient suffered from a ruptured abdominal aortic aneurysm. Three patients (6%) developed a temporary neurological deficit which resolved spontaneously. Two patients (4%) developed renal failure requiring temporary hemodialysis. Pulmonary complications occurred in 12 patients (25%). CONCLUSION: Continuous antegrade cerebral perfusion via selective grafts to the innominate and carotid arteries offers adequate protection in patients undergoing replacement of the ascending aorta or aortic arch and great vessels. This technique allows radical repair and optimal vascular reconstruction without time restrains and avoids the necessity for profound hypothermia     

Usefulness of antegrade selective cerebral perfusion during aortic arch operations

BACKGROUND: To evaluate the safety and usefulness of antegrade selective cerebral perfusion (SCP) during arch aneurysm or aortic dissection operations. METHODS: Between January 1986 and December 2001, 330 patients underwent aortic arch repair using SCP. Operations were performed with the aid of hypothermic extracorporeal circulation, SCP, and systemic circulatory arrest in most cases. In all, 89 patients (27%) were operated on for acute aortic dissection, 77 (23%) for chronic aortic dissection, and 164 (50%) for degenerative aneurysm. Total arch replacement using a branched graft was performed in 288 patients (94%). Mean SCP time was 86.2 +/- 28.5 minutes. RESULTS: The overall in-hospital mortality rate was 11.2% (falling to 3.2% in the 124 patients operated on between 1997 and 2001). Independent determinants of hospital mortality were pump time, renal/mesenteric ischemia, chronic renal failure, increasing age, period of operation, and nonuse of four-branched arch graft. The overall postoperative incidences of temporary and permanent neurologic dysfunction were 4.2% and 2.4%, respectively. There was no significant correlation between SCP time and in-hospital mortality or neurologic outcome. CONCLUSIONS: Selective cerebral perfusion is a reliable technique for cerebral protection and it facilitates complex and time-consuming total arch replacement.     

Progress in the treatment of aneurysms of the distal aortic arch: approach through median sternotomy

AIM: A review of past and current operative procedures for the treatment of aneurysms of the distal aortic arch is presented in conjunction with a series of 43 patients. In this study, distal aortic arch aneurysm refers to an aneurysm involving at least the origin of the left subclavian artery, but not extending beyond the left common carotid artery. We excluded dissection aneurysm and extended aneurysm to the descending thoracic aorta from this study. METHODS: Between January, 1985, and March, 2000, 43 consecutive patients (37 males, 6 females; mean age 67.5 years) underwent repair of aneurysms of the distal aortic arch. The approach to the aneurysm was through a left thoracotomy in 4 patients and a median sternotomy in 39 patients, including an additional left thoracotomy continued to a median sternotomy in 2 patients. The supportive methods during surgery were left heart bypass using a centrifugal pump in 4 patients (LHB group), cardiopulmonary bypass with selective cerebral perfusion in 11 patients (SCP group), and cardiopulmonary bypass with continuous retrograde cerebral perfusion in 28 patients (RCP group). In the RCP group, the "aortic no-touch technique" was applied in 21 patients. The operative methods were patch closure in 4 patients, graft replacement of the distal arch using the inclusion technique in 14 patients, and total arch replacement using the exclusion technique in 25 patients. RESULTS: There were 5 hospital deaths: 1 patient in the LHB group, intractable bleeding; 1 patient in the SCP group, rupture of the distal anastomosis; 3 patients in the RCP group, stroke, rupture of the dissection arising from the distal anastomosis, and perioperative myocardial infarction. Stroke occurred in 1 patient (25%) with LHB, 3 patients (27.2%) with SCP, and 1 patient (3.6%) with RCP. Among the postoperative survivors, a new onset of left recurrent nerve palsy occurred in 2 patients (66.7%) with LHB, 1 patient (10%) with SCP, and in 1 patient (4%) with RCP. No neurological injury or left recurrent nerve palsy occurred in the patients who underwent the "aortic no-touch technique". CONCLUSION: Total arch replacement with the graft exclusion technique under profound hypothermic circulatory arrest using RCP through the median sternotomy is a promising surgical treatment for atherosclerotic distal aortic arch aneurysm. The "aortic no-touch technique" further improved the surgical results of the distal aortic arch aneurysm.     

A reconsideration of cerebral perfusion in aortic arch replacement

Ten patients underwent aortic arch replacement for aneurysmal disease from 1970 to 1985 using a simplified cardiopulmonary bypass (CPB) technique with partial brachiocephalic perfusion, low CPB flow (30 to 50 ml/kg/min), moderate systemic cooling (26 degrees to 28 degrees C), and topical hypothermic myocardial protection. The arterial line from a single pump head has a Y shape to perfuse the femoral artery (20F cannula) and either the innominate or left carotid artery (14F). Of the 10 patients (mean age, 58 years) with arch aneurysm (6 atherosclerotic, 2 dissections, and 2 degenerative), 3 had previously undergone major cardiovascular operations. Concomitant procedures included aortic valve replacement in 4 and coronary artery bypass grafting in 3. Eight patients survived the procedure, and 1 died three weeks after operation of a ruptured abdominal aneurysm. Among the survivors, CPB time was 119 +/- 36 minutes (+/- standard deviation), myocardial ischemia time was 79 +/- 32 minutes, and intraoperative blood requirement was 5.9 +/- 3.4 units. There were no postoperative strokes. Neurological complications were only minor and included an asymptomatic miosis and ulnar nerve paresthesias in 1 patient and transient vocal cord palsy in another. Applicable in most patients undergoing elective resection of degenerative and atherosclerotic arch aneurysms and in selected patients with arch dissections, this simplified technique of brachiocephalic perfusion without circulatory arrest provides an attractive and safe alternative; the potential advantages are technical simplicity, reduced CPB and operating times, and satisfactory cerebral protection.     

Surgical treatment of an aneurysm of the aberrant right subclavian artery involving an aortic arch aneurysm and coronary artery disease.

A 55-year-old man presented with clinical signs of an aortic arch aneurysm. Angiography, MRI and CT demonstrated an aortic arch aneurysm and an aneurysm of the aberrant right subclavian artery. Coronary angiography revealed 95% stenosis in the right coronary artery. Right common carotid artery-right subclavian artery bypass, arch graft replacement and coronary artery bypass grafting were performed successfully. The use of internal shunt tube, hypothermic circulatory arrest and selective cerebral perfusion were useful methods in prevention of cerebral ischemia during surgical reconstruction of the aortic arch. To our knowledge, this is the first report in the literature of a successfully managed case with an aneurysm of an aberrant right subclavian artery involving an aortic arch aneurysm and coronary artery disease.     

Hydrodynamics of aortic arch vessels during perfusion through the right subclavian artery

BACKGROUND: Performing subclavian artery cannulation in patients with an atherosclerotic ascending aorta or acute aortic dissection is of growing interest. To increase knowledge about pressure and flow distribution in the arch vessels, we investigated the in vitro perfusion characteristics in right subclavian artery cannulation. METHODS: Pressures and flow rates in the arch vessels of an aortic arch model were measured during perfusion through the right subclavian artery with different geometries and varying flow rates. Flow visualization was performed by laser light. RESULTS: In normal subclavian artery geometries, pressure and flow showed a significant increase in only the right common carotid artery (8 mm Hg and 25.5 mL/min, respectively, at 5.5 L/min pump flow). In cases of 50% stenosis at the right subclavian artery origin, a reduction of pressure and flow (6 mm Hg and 22.5 mL/min, respectively, at 5.5 L/min pump flow) in the right carotid artery caused by a suction effect was observed. CONCLUSIONS: Right subclavian artery cannulation provides a valuable alternative for ascending aortic cannulation, enabling nearly balanced arch vessel perfusion. Stenosis at the right subclavian artery origin carries the potential risk of slightly reduced perfusion of the right common carotid artery with questionable clinical relevance.     

Antegrade selective cerebral perfusion for extended total arch replacement using separated graft technique; reassessment from the type of aneurysms and dissections

One hundred eighty two patients with thoracic aortic aneurysms or dissections who required total arch replacement (TAR) were operated on with separated graft technique and selective cerebral perfusion (SCP) between 1991 and 2000. These patients were divided into 4 groups according to the pathology as follows: group 1; acute type A dissection, group 2; chronic type A dissection, group 3; distal arch aneurysm and group 4; proximal arch aneurysm. For SCP, both the innominate artery and the left common carotid artery were cannulated when the patient was cooled to a rectal temperature of 22 degrees C. Hospital mortalities were 27% in group 1, 14% in group 2, 19% in group 3, and 8% in group 4. Independent predictors of hospital mortality were shock, visceral, and leg ischemia in group 1, and circulatory arrest time of the lower half body to be more than 1 hour and cardiopulmonary bypass time to be more than 5 hours in group 3. Permanent neurological complication occurred in 3% in group 1 and 8% in group 3. Hospital mortality was affected by the type of aneurysms and dissections. It is necessary to give careful consideration to the indication of TAR with SCP, especially in acute type A dissection and distal arch aneurysm.     

Neonatal repair of right interrupted aortic arch with cerebro-myocardial perfusion technique

Right interrupted aortic arch and descending aorta is exceedingly rare and most likely cause respiratory presentation, since patent ductus arteriosus (PDA) courses over the right mainstem bronchus. We report a case of successful neonatal biventricular repair of a right interrupted aortic arch (type B), with an aberrant right subclavian artery ventricular septal defect (VSD) in a 2.7?kg term neonate with DiGeorge syndrome. Patient presented in severe respiratory distress and acidosis at one day old. Two-dimensional (2D) echocardiography revealed aortic arch interruption beyond the common carotid arteries with large perimembranous outlet VSD. Aortic annulus diameter was 4.8?mm and there was no left ventricle (LV) outflow tract obstruction. Three-dimensional (3D) CT-scan confirmed these findings and identified a right-sided ductal arch that continued over the right mainstem bronchus into a right-sided descending aorta and aberrant right subclavian artery. Brachiocephalic perfusion and ductal perfusion was employed for cooling during cardiopulmonary bypass. Under deep hypothermia (27 °C rectal temperature), selective cerebro-myocardial perfusion was used for successful aortic arch repair without sacrificing the aberrant right subclavian artery. A direct tension-free anastomosis was attained. Her postoperative course was uneventful and her respiratory symptoms disappeared postoperatively. Early surgical correction is mandatory for these patients with unique anatomy and presentation.     

Minimized mortality and neurological complications in surgery for chronic arch aneurysm: axillary artery cannulation, selective cerebral perfusion, and replacement of the ascending and total arch aorta

OBJECTIVE: Cerebral complication is still a major concern in surgery for arteriosclerotic aortic arch disease. For preventing this complication, axillary artery cannulation, selective cerebral perfusion, and replacement of the ascending and arch aorta were applied to thoracic aortic aneurysm involving aortic arch. METHOD: From May 1999 to July 2002, consecutive 39 patients with true aneurysm (29 patients) or chronic aortic dissection (10 patients) involving aortic arch underwent replacement of the ascending and arch aorta with an elephant trunk under hypothermic cardiopulmonary bypass through the axillary artery cannulation and selective cerebral perfusion. The brain was continuously perfused without any intermission through the axillary artery. Concomitant operation included coronary artery bypass grafting (CABG) in two patients, aortic valve replacement (AVR) in one, Bentall operation in two, mitral valve replacement (MVR) in one, and aortic valve sparing operation in one. Patient age at operation was 40-84 (72 + 9) years and 24 of them were older than 70 years of age. RESULTS: There was one operative death (2.5%) due to bleeding from the left lung, and one hospital death due to respiratory failure. Postoperative permanent neurological dysfunction was found in one patient (2.5%). Two patients presented temporary neurological dysfunction (5%). Thirty-six of the 39 patients were discharged from hospital on foot. CONCLUSION: Continuous perfusion through the axillary artery with selective cerebral perfusion and replacement of the ascending and arch aorta may minimize cerebral complication leading to satisfactory results in patients with chronic aortic aneurysm involving aortic arch.     

Aortic arch replacement using a trifurcated graft and selective cerebral antegrade perfusion

BACKGROUND: Aortic arch aneurysm repair remains associated with considerable mortality and risk of cerebral complications. We present results of a technique utilizing a three-branched graft for arch replacement, deep hypothermic circulatory arrest (HCA), and selective antegrade cerebral perfusion (SCP). METHODS: Between March 2000 and November 2001, 22 patients (11 female) aged 40 to 77 years (mean 64 +/- 11.2) underwent arch replacement utilizing the trifurcated-graft technique. Serial anastomosis of the branched graft to individual cerebral vessels was carried out during HCA, followed by arch reconstruction during SCP through the graft. All 22 patients had surgery electively. Eight patients (36%) had undergone previous aortic surgery. In 19 patients, arch replacement was part of an elephant trunk procedure; 2 patients had Bentall operations and 1 had isolated arch replacement. Concomitant coronary artery bypass grafting was performed in 6 patients (27%). Mean HCA duration was 30 +/- 6 minutes at a mean temperature of 11.4 +/- 0.8 degrees C. Mean duration of SCP was 52 +/- 18 minutes. RESULTS: Adverse outcome--death before hospital discharge or permanent stroke or both--occurred in 2 patients (9%). Two patients experienced transient neurologic dysfunction (9%). Two patients (9%) developed renal failure requiring short-term hemodialysis and pulmonary complications occurred in 2 patients. CONCLUSIONS: Cerebral protection and prevention of atheroembolism remain challenges in aortic arch reconstruction. To reduce neurologic complications we developed an aortic arch reconstruction technique in which a trifurcated graft is anastomosed to the brachiocephalic vessels during HCA, reducing the risk of embolization while minimizing cerebral ischemia by permitting antegrade cerebral perfusion as arch repair is completed.     

Operative management of Stanford type A aortic dissection using selective cerebral perfusion]

Ten patients underwent surgical treatment for type A aortic dissection from October 1986 to April 1989 using hypothermic cardiopulmonary bypass (CPB) with selective cerebral perfusion (SCP). CPB was begun with femoral artery cannulation. The right axillary artery (RAA) and the left common carotid artery (LCCA) were separately cannulated and perfused with CPB blood by individual pump heads. The average flow to the RAA was 5.4 +/- 1.2 ml/min/kg body weight (mean +/- SD) and 5.6 +/- 2.6 ml/min/kg body weight to the LCCA. The average blood pressure of the superficial temporal artery was 53.1 +/- 15.1 mmHg in the right side and 52.5 +/- 24.7 mmHg in the left. The nasopharyngeal temperature during SCP was maintained at 19.3-24.7 degrees C (mean, 21.1 degrees C). The SCP time ranged from 112 to 197 minutes (mean, 168 +/- 20.8 minutes). There was one operative death. She died of myocardial infarction 3 days after operation. There were two late deaths. One patient died of infection 3 months after operation and another died of cholecystitis 4 months after operation. Cerebral infarction developed in the last patient. Among the 10 patients it was only one neurological sequela, which was surmised to be caused by technical problem in carotid artery cannulation. The good cerebral protection was obtained in our experience by SCP as mentioned above.     

Cannulation of the innominate artery during surgery of the thoracic aorta: our experience in 55 patients.

BACKGROUND: Alternative cannulation sites such as the right/left axillary artery, the ascending aorta and aortic arch have been recently preferred to the femoral artery to improve neurologic outcome in patients undergoing surgery of the thoracic aorta. In 2004, we started to select the innominate artery as an arterial cannulation site for CPB and antegrade cerebral perfusion institution. Here we present our preliminary experience with 55 patients. METHODS: Between November 2004 and 2006, 55 patients (mean age 60+/-14 years) underwent surgery on the thoracic aorta using the innominate artery as a site for arterial cannulation. Indication for surgery was a degenerative aneurysm in 49 (89.1%), an acute type A dissection in 2 patients (3.6%), a post-dissection aneurysm in 3 (5.4%), a supravalvular aortic stenosis in 1 patient (1.8%). Operative procedure included total arch replacement (n=9), hemiarch replacement (n=6), ascending aorta replacement (n=21), Bentall procedure (n=18) and aortoplasty with patch (n=1). Mean CPB and cross clamp times were 131+/-60 and 95+/-29 min, respectively. Mean cerebral perfusion time was 54+/-26 min. RESULTS: The hospital mortality rate was 3.6%. There were no permanent neurologic dysfunction and one (1.8%) temporary neurological dysfunction. CONCLUSION: Our results with the cannulation of the innominate artery were encouraging. This provides the same advantages of the axillary artery cannulation with greater simplicity and avoiding extra surgical incisions which may be site for local complications. It may represent a valid option for CPB and antegrade cerebral perfusion institution in aortic procedures.     

The methodologies of hypothermic circulatory arrest and of antegrade and retrograde cerebral perfusion for aortic arch surgery

In spite of recent advances in thoracic aortic surgery, postoperative neurological injury still remains the main cause of mortality and morbidity after aortic arch operation. The use of cardiopulmonary bypass (CPB) and hypothermic circulatory arrest, temporary interruption of brain circulation, transient cerebral hypoperfusion, and manipulations on the frequently atheromatic aorta all produce neurological damages. The basic established techniques and perfusion strategies during aortic arch replacement number three: hypothermic circulatory arrest (HCA), antegrade cerebral perfusion (ACP), and retrograde cerebral perfusion (RCP). During the past decade and after several experimental studies, RCP lost its previous place in the armamentarium of brain protection, giving it up to ACP as a major method of brain perfusion during HCA. HCA should be applied at a temperature of asymptotically equal to 20 degrees C with long-lasting cooling and rewarming and should not exceed by itself the time of 20-25 min. RCP does not seem to prolong safe brain-ischemia time beyond 30 min, but it appears to enhance cerebral hypothermia by its massive concentration inside the brain vein sinuses. HCA combined with ACP, however, could prolong safe brain-ischemia time up to 80 min. Cold ACP at 10 degrees -13 degrees C should be initially applied through the right subclavian or axillary artery and continued bihemispherically through the left common carotid artery at first and later the anastomosed graft, with a mean perfusion pressure of 40-70 mm Hg. The safety of temporary perfusion is being confirmed by the meticulous monitoring of brain perfusion through internal jugular bulb O2 saturation, electroencephalogram, and transcranial comparative Doppler velocity of the middle cerebral arteries.     

不同腋动脉插管方法在StanfordA型主动脉夹层手术中的应用

目的比较两种不同右侧腋动脉插管方法对Stanford A型主动脉夹层患者行主动脉弓置换术的安全性和临床效果。方法 2008年7月至2010年7月北京安贞医院对280例Stanford A型主动脉夹层患者采用右侧腋动脉插管建立体外循环(CPB),行全弓置换+降主动脉支架人工血管植入术。根据术中腋动脉插管方式将280例患者分为两组,直接插管组(n=215),年龄(43.1±9.5)岁,行直接腋动脉插管;间接插管组(n=65),年龄(44.7±8.3)岁,腋动脉连接人工血管行间接插管。观察两组患者的安全性,比较相关手术参数、临床结果和术后恢复情况。结果住院死亡10例,其中直接插管组7例(7/215,3.3%),间接插管组3例(3/65,4.6%);所有患者均成功行腋动脉插管;术后25例(25/280,8.9%)出现暂时性神经系统功能障碍,其中直接插管组19例(8.8%),间接插管组6例(9.2%),均经治疗痊愈。间接插管组患者术后腋动脉插管并发症明显少于直接插管组,差异有统计学意义((1例vs.19例,P=0.045)。两组患者体外循环期间最高流量、最高泵压,深低温停循环时间、顺行性脑灌注时间和CPB时间差异均无统计学意义(P0.05)。结论经人工血管右侧腋动脉插管可以降低腋动脉插管相关并发症,安全用于Stanford A型主动脉夹层患者的外科手术治疗。     

Moderately hypothermic cardiopulmonary bypass and selective cerebral perfusion in ascending aorta and aortic arch surgery. Preliminary experience in twenty-two patients

Deep hypothermic cardiocirculatory arrest is the commonest method of brain protection during transverse aortic arch surgery. Its principle drawbacks consist in the limited safe ischemic period and in the coagulative, renal and pulmonary complications related to low body temperatures and prolonged cardiopulmonary bypass time. Different selective cerebral perfusion techniques have recently raised the interest of some surgical teams in an effort to obviate these problems. The authors' initial experiences with 22 patients, ranging in age from 19 to 78 years (mean, 55±15 years), who underwent ascending aorta and/or aortic arch replacement using selective cerebral perfusion and moderately hypothermic cardiopulmonary bypass are reported here. Acute aortic dissection and atherosclerotic aneurysm were the commonest lesions observed: ascending aorta associated with partial or complete arch replacement was the most widely performed procedure. With regard to the perfusion technique, after regular cardiopulmonary bypass had been established through the iliac vessels, selective cerebral perfusion was started after aortic arch vessels cannulation (innominate artery, bilateral common carotid artery, innominate artery and left common carotid artery, or right common carotid artery) using a single roller pump separately from the systemic circulation, and brain perfusion was achieved by blood cooled at 30°C, at a flow rate that ranged from 300 ml/min to 1500 ml/min, at a perfusion pressure of ~65 mmHg, with the patient maintained at moderate hypothermia (30°C rectal). To perform distal aortic repair, if transverse aortic arch or proximal descending aorta cross-clamping was not feasible, cardiopulmonary bypass flow was lowered to 300–350 ml/min and an open anastomosis was performed, while independently assuring cerebral perfusion (six patients). There were three hospital deaths (mortality rate of 13.6%; s.d. 6.0–25.5%; 70% confidence limit), but none because of cerebral accident. No paraplegia occurred. One patient suffered from right hemiparesis, neither renal nor pulmonary complications were observed. Two chest reexplorations were necessary for bleeding, which were partially related to hemocoagulative disorders. In our experience, the technique of moderately hypothermic cardiopulmonary bypass and selective cerebral perfusion in aortic surgery has provided good results with regard to cerebral protection and organ function preservation. Therefore, allowing a prolonged distal aortic reconstruction period, it may be considered as a safe alternative to profound hypothermia associated with cardiocirculatory arrest in aortic arch surgery.     

Surgical treatment of the aortic arch dissection--a report of two cases operated by partial brachiocephalic perfusion, and open aortic anastomosis

Two patients underwent aortic arch replacement for the dissecting aneurysm of the aorta using a simplified cardiopulmonary bypass (CPB) technique with partial brachiocephalic perfusion, moderate systemic cooling (22 degrees to 23 degrees C), and open aortic anastomosis were reported. The partial brachiocephalic perfusion was accomplished by perfusion to the right axillary artery using separate pump. Open distal anastomosis was performed under low flow hypothermic perfusion of the lower body during selective perfusion to the brain. Cardiopulmonary bypass and partial brachiocephalic perfusion time were 170 minutes, and 30 minutes in one case, and 207 minutes, 56 minutes in the other case. Both patients survived operations, and there were no postoperative strokes, and neurological complications. On the basis of these results, we discussed about supportive methods for aortic arch surgery.     

Hydrodynamic evaluation of axillary artery perfusion for normal and diseased aorta

Axillary artery perfusion is an attractive alternative to reduce the frequency of atheroembolism in extensive atherosclerotic aorta and aortic aneurysms. This study was conducted to evaluate the flow dynamics of axillary artery perfusion. Transparent glass models of a normal aortic arch and an aortic arch aneurysm were used to evaluate hydrodynamic properties. Streamline analysis and distribution of the shear stress was evaluated using a particle image velocity method. In the normal aortic arch model, rapid flow of 80 cm/s from the right axillary artery ran out from the brachiocephalic artery and grazed the lesser curvature of the aortic arch. There was secondary reversed flow in the ascending aorta. Flow from left axillary perfusion went straight to the descending aorta. In the aortic arch aneurysm model, flow from both axillary arteries hit the lesser curvature of the aortic arch and went into the ascending aorta with vortical flow. Distribution of shear stress was high along the jet from the ostium of the brachiocephalic artery and left subclavian artery. Flow in the aortic arch and the ascending aorta was unexpectedly rapid. Special care must be taken when the patient has frail atheroma around arch vessels or the lesser curvature of the aortic arch during axillary artery perfusion.     

Cannulation of the Extrathoracic Left Common Carotid Artery for Thoracic Aorta Operations Through Left Posterolateral Thoracotomy

The femoral artery is the usual site of arterial cannulation in thoracic aorta operations through left posterolateral thoracotomy that require cardiopulmonary bypass (CPB) with deep hypothermic circulatory arrest (DHCA). The advantage of this perfusion route is in limiting the duration of circulatory arrest. It is associated, however, with the risk of retrograde embolization or, in cases involving aortic dissection, malperfusion of vital organs. To prevent these risks, we have used the extrathoracic left common carotid artery as the perfusion route. From December 1999 to January 2003, we used cannulation of the left extrathoracic common carotid artery in 42 thoracic aorta operations through posterolateral thoracotomy with an open proximal anastomosis technique during DHCA. The indication for thoracic aortic repair was atherosclerotic ulcer in 7 cases, chronic aortic aneurysm in 18, acute type B dissection in 5, and chronic type B dissection in 12. Cannulation of the extrathoracic left common carotid artery was successful in all patients. Postoperative recovery was uneventful, with no cerebrovascular events in all cases. No cannulation-related complications were observed. One patient died from cardiac insufficiency on postoperative day 5. No peripheral neurological deficits (paraplegia or paraparesis) were observed. Postoperative complications included atrial fibrillation in five patients, reoperation to control hemorrhage in six, respiratory insufficiency in nine, and renal insufficiency in six. These results indicate that cannulation of the left extrathoracic common carotid artery is a useful, reliable method for proximal perfusion during CPB in patients undergoing repair of the descending thoracic aorta through left posterolateral thoracotomy. By providing effective perfusion of the brain, this technique can prolong safe DHCA time. Another advantage is the prevention of cerebral emboli, ensuring retrograde flow to the aortic arch.Presented at the Eighteenth Annual Meeting of the Société de Chirurgie Vasculaire de Langue Française, Toulouse, France, May 21-24, 2003.     

The use of an extra-corporeal graft to maintain cerebral perfusion during thoracic endovascular aneurysm repair.

Endovascular access for aneurysm repair can be challenging in patients with iliofemoral occlusive disease. The carotid artery is an alternative access site, but may increase the risk of cerebral hypoperfusion during stent delivery. We describe a novel approach, where temporary extra-corporeal bypass was used to maintain cerebral perfusion during endovascular thoracic aneurysm repair via the carotid artery, in a patient with significant aorto-iliac and arch vessel disease.