胸主动脉夹层的外科治疗

目的总结胸主动脉夹层(AD)的外科治疗经验。方法1993年至2003年4月手术治疗A型AD40例，B型20例，其中急性夹层16例。A型采用中度低温体外循环13例，深低温停循环(DHCA)和上腔静脉逆灌(RCP)27例；行升主动脉置换24例，升主动脉和半弓置换11例，升主动脉、全弓和象鼻手术5例；同期行Bentall手术18例，主动脉瓣置换8例，冠状动脉旁路移植术1例。B型采用左心转流7例，股一股转流2例，DHCA 11例；行近端降主动脉置换14例，全胸降主动脉置换或伴肋间动脉移植6例。结果全组术后死亡率10％(急性夹层18．8％，慢性夹层6．8％)，近3年降至4．4％。术后并发呼吸功能不全8例，二次开胸止血3例，延迟性心包压塞和腹腔内出血各2例，声音嘶哑3例。结论正确掌握手术指征、手术技巧和术中脑保护是手术治疗AD的关键。A型夹层的手术范围应依据内膜破裂口位置决定。     

Hypothermic circulatory arrest does not increase the risk of ascending thoracic aortic aneurysm resection.

OBJECTIVE: The purpose of this study was to investigate the safety and efficacy of a period of deep hypothermic circulatory arrest (DHCA) during elective replacement of the ascending thoracic aorta. SUMMARY BACKGROUND DATA: DHCA has been implemented in ascending thoracic aortic aneurysm resection whenever the anatomy or pathology of the aorta or arch vessels prevents safe or adequate cross-clamping. Profound hypothermia and retrograde cerebral perfusion have been shown to be neurologically protective during ascending aortic replacement under circulatory arrest. METHODS: The authors conducted a retrospective analysis of 91 consecutive patients who underwent repair of chronic ascending thoracic aortic aneurysms from 1986 to present. The authors hypothesized that patients undergoing DHCA with or without retrograde cerebral perfusion during aneurysm repair were at no greater operative risk than patients who received aneurysm resection while on standard cardiopulmonary bypass. RESULTS: There were no significant differences in hospital mortality, stroke rate, or operative morbidity between patients repaired on DHCA when compared to those repaired on cardiopulmonary bypass. CONCLUSIONS: DHCA with or without retrograde cerebral perfusion does not result in increased morbidity or mortality during the resection of ascending thoracic aortic aneurysms. In fact, this technique may prevent damage to the arch vessels in select cases and avoid the possible complications associated with cross-clamping a friable or atherosclerotic aorta.     

Clinical application of retrograde cerebral perfusion for brain protection during surgery of ascending aortic aneurysm--a report of 50 cases

This study was designed to discuss the effects on the brain by different protective methods in ascending aortic aneurysm surgery retrospectively. Two hundred seventy-one surgeries of ascending aortic aneurysm have been done in the past 15 years. There were 65 patients with a dissecting aneurysm of the aortic arch or right arch. To protect the brain, deep hypothermic circulatory arrest (DHCA) combined with retrograde cerebral perfusion (RCP) through superior vena cava (N = 50) and simple DHCA (N = 15) were used during the procedure. Blood samples for lactic acid level from the jugular vein were compared in both groups. Perfusion blood distribution and oxygen content difference between the perfused blood and returned blood were measured in 5 and 10 of RCP patients, respectively. The DHCA time was 35.86 +/- 18.81 min (10 approximately 63 min) and DHCA + RCP time was 45.5 +/- 17.21 min (16 approximately 81 min). The resuscitation time was 7.11 +/- 1.59 h (4.4 - 9.4 h) in DHCA versus 5.43 +/- 2.15 h (2 approximately 9 h) in RCP patients. The operation death rate was 3/15 in DHCA group and 1/50 in RCP patients. Central nervous complication occurred in 3/12 of DHCA patients and 1/49 of RCP patients (p < .01). The overall survival rate was 96% (RCP) versus 67% (DHCA); the central nervous system dysfunction was 20% in DHCA versus 2% in RCP (p < .001). The blood lactic acid level increased significantly after reperfusion in DHCA than that in RCP. The measurement of blood distribution indicated that approximately 2Q% of the perfused blood returned from arch vessels. The difference of oxygen content between perfused and returned blood showed that the oxygen uptake was adequate in RCP group. The application of RCP can prolong the safety duration of circulation arrest. Continuous cerebral perfusion may maintain the brain at a cooler temperature and flush out particulate and air emboli while open anastomosis of the aortic arch to the prosthesis can be safely performed. Therefore, RCP is a preferable method for brain protection in our clinical practices.     

经上腔静脉逆行灌注脑保护在主动脉瘤手术中的应用

目的　探讨在主动脉瘤手术中应用经上腔静脉逆行灌注的脑保护效果。　方法　 65例主动脉瘤患者分 2组 ,15例采用深低温停循环 (DHCA) ,5 0例经上腔静脉逆行灌注 (RCP)进行脑保护。术中比较 2组患者不同时间颈内静脉的血乳酸含量 ,对部分RCP患者测定了灌注血和回流血的流量分布 ,以及灌注血和回流血的氧含量。　结果　DHCA组停循环时间为 10 0～ 63 0min ,平均(3 5 9± 18 8)min ;RCP组为 16 0～ 81 0min ,平均 (45 5± 17 2 )min。术后至清醒时间DHCA组为4 4～ 9 4h ,平均 (7 1± 1 6)h ;RCP组 2 0～ 9 0h ,平均 (5 4± 2 2 )h。DHCA组手术死亡 3例 ,RCP组死亡 1例 ;术后神经系统并发症DHCA组 3例 (死亡 2例 ,成活 1例 ) ,RCP组 1例 (存活 )。手术总成功率和神经系统并发症发生率RCP组分别为 96%和 2 % ,DHCA组为 67%和 2 0 % (P <0 0 5 )。RCP组再灌注期间颈内静脉血乳酸含量增高幅度低于DHCA组 [(4 4± 0 6)mmol/Lvs (6 2± 0 9)mmol/L ,P <0 0 1],经头臂和下腔静脉血流量测定显示约 2 0 %血液经头臂动脉回流 ,灌注血和回流血氧差9 0 0～ 13 67ml/L ,证实RCP期间脑组织有氧利用。　结论　在主动脉瘤手术中 ,应用RCP可以延长停循环的安全时限 ,是可行的脑保护方法     

升主动脉和弓部动脉瘤的外科治疗

目的：总结升主动脉和弓部动脉瘤手术治疗经验，以期进一步提高手术疗效。方法：自2000年7月至2002年5月应用深低温停循环（DHCA）和上腔静脉逆行脑灌注（RCP）技术手术治疗升主动脉和弓部动脉瘤20例，其中急症手术5例。施行全弓置换术2例，全弓置换和象鼻手术3例，半弓置换术15例。同期行Bentall手术8例，升主动脉置换术或同时行主动脉瓣置换术12例，冠状动脉旁路移植术1例。结果：术后早期死亡1例，短时间浅昏迷1例，呼吸功能不全2例，肾功能不全2例，无晚期死亡。结论：DHCA和RCP技术是手术治疗升主动脉和弓部瘤的安全、有效方法，急性A型夹层动脉瘤的手术方式取决于内膜破裂口的位置；正确掌握DHCA和RCP技术，手术方式和手术技术、围术期处理是提高手术疗效的关键因素。     

胸主动脉瘤合并冠心病的外科治疗

目的探讨行胸主动脉瘤置换同期行冠状动脉旁路移植术的安全性及其对预后的影响。方法1982年5月至2004年10月我院收治67例胸主动脉瘤患者,其中同时行冠状动脉旁路移植术者24例：行降主动脉置换+冠状动脉旁路移植术9例,升主动脉置换+冠状动脉旁路移植术15例。将其术后结果与同期仅行胸主动脉置换者进行对比。结果同期行冠状动脉旁路移植术者总病死率为13%(3/24),同期行降主动脉置换+冠状动脉旁路移植术者虽因心肺转流和选择性脑灌注使手术时间显著延长[(278±54)与(188±59)min,t=5．397,P＜0．05],但术后并发症发生率、3年生存率和3年无心脏意外率与单纯行胸主动脉置换术者比较,差异无统计学意义(P＞0．05)。结论同期胸主动脉瘤置换+冠状动脉旁路移植术安全可靠,有助于防止因冠心病而致术后远期发生心脏意外。     

Stanford A型主动脉夹层的外科治疗

目的总结A型主动脉夹层的外科治疗经验。方法回顾分析手术治疗68例StanfordA型主动脉夹层患者的临床资料。其中急性主动脉夹层45例,慢性主动脉夹层23例。采用中低温体外循环53例,深低温停循环(DHCA)和上腔静脉逆行灌注脑保护11例,DHCA加选择性脑灌注4例。急诊手术39例(其中紧急手术19例),择期手术29例。术式为升主动脉置换术7例,升主动脉加右半弓置换术6例,升主动脉加全弓置换术3例,升主动脉加全弓置换加术中支架置入术4例,Bentall手术34例,改良的Wheat术12例,同时行主动脉瓣成形术2例、二尖瓣成形1例。结果全组死亡5例(7%),其中急诊手术3例,急诊手术病死率8%(3/39);择期手术2例,择期手术病死率7%(2/29)。共随访58例,随访率92%(58/63),随访时间(37±22)个月(5~77个月),死亡4例,累积1,3和5年的生存率分别是100%,95%和86%。结论StanfordA型夹层的手术方式应根据内膜破口位置决定,正确的手术指征、技巧和脑保护是手术成功的关键。     

Cerebral protection during surgery for aortic arch aneurysms.

Surgical repair of aneurysms or dissections involving the transverse aortic arch and the distal aortic arch carries a considerable risk of cerebral complications. Currently, deep hypothermic circulatory arrest (DHCA), moderate hypothermic circulatory arrest or DHCA with selective cerebral perfusion (SCP) and DHCA with retrograde cerebral perfusion (RCP) are used as means to protect the central nervous system. DHCA alone is simple, but the safe time of DHCA is limited. RCP is an alternative technique for cerebral protection that can prolong the safe time of DHCA. SCP offers virtually unlimited time in isolating cerebral circulation. With the improvement of cardiopulmonary bypass (CPB) materials and myocardial preservation, DHCA with SCP is our current preference of an adjunct for cerebral protection, although possible increment of mortality and morbidity associated with a prolonged DHCA and CPB remains to be overcome.     

Direct visualization of minimal cerebral capillary flow during retrograde cerebral perfusion: an intravital fluorescence microscopy study in pigs

BACKGROUND: Retrograde cerebral perfusion (RCP) is used in some centers during aortic arch surgery for brain protection during hypothermic circulatory arrest. It is still unclear however whether RCP provides adequate microcirculatory blood flow at a capillary level. We used intravital microscopy to directly visualize the cerebral capillary blood flow in a piglet model of RCP. METHODS: Twelve pigs (weight 9.7 +/- 0.9 kg) were divided into two groups (n = 6 each): deep hypothermic circulatory arrest (DHCA) and RCP. After the creation of a window over the parietal cerebral cortex, pigs underwent 10 minutes of normothermic bypass and 40 minutes of cooling to 15 degrees C on cardiopulmonary bypass ([CPB] pH-stat, hemocrit 30%, pump flow 100 mL x kg(-1) x min(-1)). This was followed by 45 minutes of DHCA and rewarming on CPB to 37 degrees C. In the RCP group the brain was retrogradely perfused (pump flow 30 mL x kg(-1) x min(-1)) during DHCA through the superior vena cava after inferior vena cava occlusion. Plasma was labeled with fluorescein-isothiocyanate-dextran for assessing microvascular diameter and functional capillary density (FCD), defined as total length of erythrocyte-perfused capillaries per observation area. Cerebral tissue oxygenation was determined by nicotinamide adenine dinucleotide hydrogen (NADH) autofluorescence, which increases during tissue ischemia. RESULTS: During normothermic and hypothermic antegrade cerebral perfusion the FCD did not significantly change from base line (97% +/- 14% and 96% +/- 12%, respectively). During retrograde cerebral perfusion the FCD decreased highly significantly to 2% +/- 2% of base line values (p < 0.001). Thus there was no evidence of significant capillary blood flow during retrograde cerebral perfusion. The microvascular diameter of cerebral arterioles that were slowly perfused significantly decreased to 27% +/- 6% of base line levels during RCP. NADH fluorescence progressively and significantly increased during RCP, indicating poorer tissue oxygenation. At the end of retrograde cerebral perfusion there was macroscopic evidence of significant brain edema. CONCLUSIONS: RCP does not provide adequate cerebral capillary blood flow and does not prevent cerebral ischemia. Prolonged RCP induces brain edema. However, there might be a role for a short period of RCP to remove air and debris from the cerebral circulation after DHCA because retrograde flow could be detected in cerebral arterioles.     

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.     

主动脉弓部手术75例

目的 总结主动脉弓部手术的方法和临床经验。方法75例弓部手术中74例采用深低温停循环（DHcA）技术，其中54例脑保护采用上腔静脉逆灌（RCP），20例采用右腋动脉顺灌（SCP）；仅1例在中度低温体外循环下行局部切除吻合。升主动脉和半弓置换53例，其中同期行降主动脉腔内支架植入术11例，弓部内膜破口修补6例，降主动脉近端内膜破口修补3例；升主动脉和全弓置换20例，其中同期行传统象鼻手术12例，降主动脉腔内支架植入4例；单纯弓部瘤切除缝合及弓部置换各1例。同期手术包括17例Bentall手术，12例AVR，3例Cabrol手术，5例二尖瓣成形术，9例主动脉瓣悬吊成形术等。DHCA9～120min，平均42．3min。结果手术死亡5例，死亡率6．7％。主要并发症为呼吸功能不全11例，肾功能不全7例，一过性精神异常9例。结论DHCA＋RCP及DHCA＋SCP技术均是主动脉弓部手术的有效方法，但后者更适用于复杂的弓部手术；手术范围和方式取决于病变性质和范围，术前状况和手术技术是影响手术效果的决定因素。     

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.     

Acute intraoperative aortic dissection following axillary artery cannulation

We describe a 75-year-old woman who underwent right axillary artery cannulation in preparation for reconstruction of the aortic arch and the proximal descending aorta for athesosclerotic aortic aneurysm via a 'clamshell' incision. As soon as cardiopulmonary bypass was established, the ascending aorta and the aortic arch was dissected. The innominate artery was dissected including one-third of its circumferance anteriorly. Arterial perfusion was stopped immediately and the left femoral artery was cannulated to resume CPB. We proceeded with replacement of the ascending aorta, the aortic arch and the proximal descending thoracic aorta with a Dacron branched aortic graft. The patient recovered uneventfully. Arterial blood pressure was equal bilaterally.     

Study in three different types of cardiopulmonary bypass on arterial ketone body ratio: its prognostic implication and participation of body temperature

The aim of this study was to investigate the change of hepatic metabolic activity presented by the ketone body ratio (AKBR) during and after cardiopulmonary bypass (CPB) and to evaluate the prognostic value. AKBR were measured in 20 cases of coronary aortic bypass grafting using moderate hypothermic CPB (group M), ten cases of aortic arch surgery using deep hypothermia with selective cerebral perfusion (DHSCP) with an open technique (group D) and 15 cases of descending thoracic aortic replacement using partial CPB (group N). AKBR decreased significantly in all groups 5 min after CPB compared with the value before CPB. There was a significant difference in AKBR 1 h after CPB among the three groups and AKBR returned to the prebypass value in group N (group M, 0.32 +/- 0.16; group D, 0.14 +/- 0.04; group N, 0.48 +/- 0.14; P < 0.0001). AKBR rose significantly after the discontinuation of CPB compared with the value during CPB and returned to the prebypass value in groups M and D. The patients who underwent DHSCP with an open technique had a value of AKBR below 0.2, but liver function still recovered normally. The value of AKBR correlated with temperature significantly and a very low level of AKBR below 0.2 was observed during core cooling to 20 degrees C without negative prognostic implications. AKBR decreased 5 min after CPB in group N which suggested decreased hepatic perfusion at an early stage of partial CPB. The prognostic implication of AKBR during CPB is whether low level AKBR recovers or not.     

Neurologic outcome after surgery of the aortic arch: Comparison of deep hypothermic arrest,antegrade and retrograde cerebral perfusion

Introduction Neurologic deficits are still a major complication of aortic arch surgery. We therefore compared cerebral protection by deep hypothermic circulatory arrest (DHCA), antegrade (ACP) and retrograde (RCP) cerebral perfusion. Patients and Method 64 consecutive patients who underwent replacement of the aortic arch for aneurysms or dissections from January 1999 through August 2001 were analysed retrospectively for clinical and neurologic outcome. For DHCA core temperature was lowered to 18°C and was kept between 18 and 24°C in the perfused groups. Selective antegrade cerebral perfusion (ACP) was achieved either via the subclavian artery or the brachiocephalic trunc. Retrograde cerebral perfusion (RCP) was performed via the superior vena cava. Results Indication for surgery was type A acute dissection or ruptured aneurysm in 39 patients, chronic dissection and aneurysm without rupture in 25 patients. Operative procedure was partial arch replacement in 46 patients and total arch replacement in 18 patients. For cerebral protection retrograde cerebral perfusion (RCP) was used in 22 Patients (23±11 min.), ACP in 30 patients (25±19 min.) and DHCA in 14 patients (23±13 min.). Mortality was 17% (11 of 64 patients: ACP 7, RCP 2 and DHCA 2). Neurologic deficits occured in 5%, without differences for groups. Conclusion For this patient cohort, needing comparatively short times for aortic arch reconstruction, a low neurologic complication rate without significant differences for the method of cerebral perfusion was observed.     

Combined grafting of thoracic aortic aneurysm and cardiac repair using continuous cold-blood coronary perfusion.

OBJECTIVE: For patients diagnosed with combined thoracic aortic aneurysms and cardiac lesions, we conduct a 1-stage operation for ascending and aortic arch grafting. We studied surgical outcome comparatively with patients undergoing aortic grafting alone. For descending and thoracoabdominal aortic grafting, we choose a 2-stage operation. SUBJECTS AND METHODS: Subjects were 80 patients undergoing ascending and aortic arch aneurysm repair between June 1994 and March 1999. Group 1 consisted of 30 undergoing simultaneous cardiac repair. Concomitant cardiac procedures involved 21 valvular, 5 coronary arterial, and 4 valvular and coronary arterial surgeries. Group 2 consisted of 50 undergoing aortic grafting alone. We used crystalloid cardioplegia and additional antegrade continuous cold-blood coronary perfusion in Group 1, and crystalloid cardioplegia alone in Group 2. RESULTS: Hospital mortality was 10% in Group 1 and 2% in Group 2. Surgery length, cardiopulmonary bypass time, and aortic cross-clamping time in Group 1 were significantly longer than Group 2. Myocardial ischemic time did not differ significantly. Postoperative ICU stay, mechanical ventilation time and catecholamine support time did not differ significantly. Actuarial survival was 66.9 +/- 13.1% at 52 months in Group 1 and 87.2 +/- 4.8% at 57 months in Group 2 (p = 0.2918). CONCLUSION: Simultaneous cardiac repair and ascending and aortic arch aneurysm repair were conducted using continuous cold-blood coronary perfusion. Hospital mortality and mid-term survival did not differ significantly between groups.     

Bronchial artery perfusion during cardiopulmonary bypass does not prevent ischemia of the lung in piglets: assessment of bronchial artery blood flow with fluorescent microspheres.

OBJECTIVE: Blood supply of the lungs during total cardiopulmonary bypass (CPB) is limited to flow through the bronchial arteries. This study was undertaken to assess the bronchial artery blood flow during CPB with fluorescent microspheres in a piglet model. METHODS: We subjected ten piglets (mean weight 5.0+/-0.5 kg) to 120 min of normothermic, total CPB without aortic cross-clamping, followed by 60 min of post-bypass perfusion. Fluorescent microspheres were injected into the left atrium or the aortic cannula or distal to the cannula to assess bronchial artery blood flow before, during and after CPB. The reference samples were taken from the descending aorta. We compared the different sites of injection. Tissue samples of the lungs were taken before and 60 min after CPB. RESULTS: Before CPB, total bronchial artery perfusion was 43.6+/-14.1 ml/min (4.8+/-1.3% of cardiac output) as by injection distal to the aortic cannula. These values were not different when microspheres were injected into the left atrium or the aortic cannula. There was no difference in scatter or in the amount of microspheres in the reference samples among the three injections sites. During CPB, bronchial artery perfusion was significantly decreased (4.4+/-2.4 ml/min vs. 40.0+/-5.0 ml/min before CPB) and returned to baseline values 60 min after CPB. Light microscopy of the tissue samples revealed alveolar septal thickening and a decrease in alveolar surface area after 60 min of reperfusion which was associated with a decreased capacity to oxygenate blood. CONCLUSIONS: (1) Bronchial artery blood flow can quantitatively be assessed during CPB when microspheres are injected into the ascending aorta and the reference samples are taken from the descending aorta. (2) Despite adequate perfusion pressure bronchial artery blood flow is decreased substantially during CPB. (3) The decrease in blood flow and the ultrastructural changes present at the end of CPB suggest the presence of low-flow ischemia of the lung during total CPB.     

The incidence of transient neurologic dysfunction after ascending aortic replacement with circulatory arrest

BACKGROUND: Transient neurologic dysfunction (TND) namely postoperative confusion, delirium, and agitation after aortic operation, particularly after deep hypothermic circulatory arrest (DHCA), remains an underestimated adverse event in the early outcome of these patients. Although no influence on long-term outcome has been reported so far, this entity markedly affects the early outcome and leads to prolonged intensive care unit and hospital stay. METHODS: Between January 1997 and January 2003, 160 consecutive patients (130 type A dissections [81%] and 30 elective atherosclerotic aneurysms [19%]) had surgical repair with DHCA for a thoracic aortic aneurysm limited to the ascending aorta. From those, 40 patients (25%) underwent DHCA alone, whereas in 13 patients (8%) antegrade cerebral perfusion and in 103 patients (64%) retrograde cerebral perfusion was used for further brain protection. RESULTS: The overall incidence of TND was 18% (28 of 160) with a significant association between duration of circulatory arrest and the incidence of TND (13.8% in DHCA < 30 minutes versus 37.9% in DHCA > 40 minutes; p < 0.05). Furthermore the severity of TND was directly associated with the duration of circulatory arrest and age. In contrast, however, the use of retrograde cerebral perfusion had no influence on the incidence of TND, (p < 0.05). Intensive care unit stay as well as hospital stay were prolonged in the patients with TND (intensive care unit 14.3 +/- 14.2 days versus 10.8 +/- 13.7 days, p < 0.05; hospital stay 15.6 +/- 10.1 days versus 11.4 +/- 7.9 days, p < 0.05). CONCLUSIONS: Duration of DHCA, regardless of whether retrograde cerebral perfusion was used, was the most important predictor of the incidence of transient neurologic dysfunction in patients who had replacement of the ascending thoracic aorta. The occurrence of TND leads to impaired functional recovery as well as prolonged intensive care unit and hospital stay.     

Cardiopulmonary bypass established via a sutured vascular graft in the presence of extraanatomic bypass

Cardiopulmonary bypass (CPB) was established via a sutured collagen sealed knitted Dacron graft in two patients who had undergone extraanatomic bypasses for lower limb ischemia, whose ascending aorta was not suitable for cannulation. One patient, with a history of femorofemoral bypass, underwent surgery for a ruptured aortic arch aneurysm (AAA) and the other patient, with a history of axillobifemoral bypass for chronic dissection involving the aortic arch and descending aorta, had unstable angina and underwent coronary artery bypass grafting. This technique of perfusion was found to be safe and effective for patients with an impaired ascending aorta who have undergone an extraanatomic bypass for the lower limb.     

Clinical study on the surgical cases of the ruptured thoracic aortic aneurysm

The prognosis of the ruptured thoracic aortic aneurysm is poor. Even if the surgical treatment was performed, the clinical outcome does not sufficiently satisfy us. Between January 1978 to July 1999, 171 cases of thoracic aortic surgery were operated in our department, in which 12 patients were with the ruptured thoracic aortic aneurysm without acute dissection. The aneurysm was located in ascending aorta (2), aortic arch (6), descending aorta (3), and thoracoabdominal aorta (1). The aneurysm was ruptured into thorax (4), pericardium (2), mediastinum (3), lung (2), and esophagus (1). The operative procedure was artificial vascular graft replacement (9), patch closure (2), and aneurysmal interposition (1) [bypass with ascending aorta to abdominal aorta)]. The operations were performed during hypothermic circulatory arrest with antegrade selective cerebral perfusion (6), under total (1) or partial complete extracorporeal circulation (5). The hospital death was 33% (4/12). The causes of death were cerebral complication (2), sepsis (1), and multiple organ failure (1). The 12 patients were divided into 2 groups: group A; 8 cases with alive; group D; 4 cases with hospital death. We compared and analyzed the perioperative factors of these 2 groups. On intraoperative factors, operation time (minute) demonstrated a significant difference (498 +/- 129 in group A v.s. 851 +/- 227 in group D, p < 0.05). No significant difference was observed between the groups on extracorporeal circulation time, aortic clumping time, selective cerebral perfusion time, systemic circulatory arrest time, intraoperative blood loss, and blood transfusion. The postoperative major complication was revealed in 6 cases (50%, 6/12), cerebral infarction (3), sepsis (2), and hoarsness (1). In conclusions, to make an effort to shorten an operative time as possible, and to prevent the postoperative neurological dysfunction under selective cerebral perfusion, those efforts should contribute to a good postoperative outcome for the ruptured thoracic aortic aneurysm.