Isolated cerebral and myocardial perfusion during aortic arch repair in neonates

OBJECTIVES: To prevent possible neurologic injury after hypothermic circulatory arrest, aortic arch obstruction with cardiac defects is repaired in one stage using isolated cerebral and myocardial perfusion (ICMP). This study investigated serum S-100 protein(S-100) levels in neonates undergoing ICMP. METHODS: Between February 2000 and January 2001, 19 neonate patients underwent repair of critical congenital heart defects. Seven of these patients with aortic coarctation(n = 3) or interrupted aortic arch (n = 4) with ventricular septal defect(ICMP group) underwent primary total repair. An arterial cannula was inserted either into the ascending aorta or into a polytetrafluoroethylene graft which was anastomosed to the innominate artery. During arch repair, a cross-clamp was placed between the innominate and left carotid arteries, and an end-to-end arch anastomosis was performed with cerebral perfusion and heart beating. During ICMP the flow was reduced to maintain a radial artery pressure of 30-45 mmHg. The remaining 12 patients underwent complete transposition of great arteries(n = 9) or total anomalous pulmonary venous connection(n = 3) using a cardiopulmonary bypass(CPB) with flow of 150-180 ml/kg/min(control group). Sequential blood samples for S-100 determinations were taken after induction of anesthesia, 30 min after aortic declamping(post-ACC), 30 min after CPB, and 24 hr after CPB. RESULTS: There were no early and late deaths. Neurologic symptoms were not observed in any patients. Mean ICMP time in ICMP group was 17 +/- 4 min. In all patients, S-100 showed the highest value post-ACC and then declined with time. There were no differences in S-100 between the groups at any other time point. CONCLUSIONS: Selective cerebral perfusion through the innominate artery may be able to maintain brain circulation.     

中度低温停循环结合选择性脑灌注在婴儿主动脉弓部手术中的应用

目的 总结中度低温停循环(moderate hypothermia circulatory arrest,MHCA)结合选择性顺行脑灌注(sective antegrade cerebral perfusion,SACP)技术在婴儿主动脉弓重建手术中的应用经验.方法 回顾性分析上海市儿童医院心胸外科于2012年1月至2018年12月间完成的主动脉弓病变合并心内畸形矫正的患儿50例.依据中心温度将患儿分为深低温停循环(deep hypothermia circulatory arrest,DHCA)组及MHCA组,每组25例.所有患儿均在体外循环(cardiopulmonary bypass,CPB)下行一期手术治疗.主动脉弓重建过程中采用低温停循环技术,通过无名动脉SACP(25~40 ml·kg^-1·min^-1)的CPB管理方法.心肌保护采用康斯特器官保护液(HTK液).记录两组患者的一般资料及术中、术后指标.结果 两组均无与CPB相关的神经系统并发症.两组患儿年龄、体重、病种、术前肝肾功能及术前左心室射血分数值比较差异均无统计学意义(P>0.05).CPB时间MHCA组较DHCA组明显缩短[(120.00±22.60)min比(137.40±22.88)min,P=0.019];术后24 h胸腔引流量及正性肌力药物评分MHCA组较DHCA组明显减少,分别为[(49.84±20.66)ml比(78.20±52.31)ml,P=0.03;(9.72±2.47)分比(12.24±3.07)分,P=0.004].结论 在婴儿主动脉弓重建手术中,采用DHCA或MHCA结合SACP的技术均能均减少术后神经系统并发症发生,不增加术后其他并发症.MHCA可减少CPB时间、术后胸腔引流量及术后血管活性药物的使用量.     

Stanford A型主动脉夹层手术中的体外循环管理

目的:总结我院165例Stanford A型主动脉夹层手术体外循环管理经验。方法:收集165例Stan-ford A型主动脉夹层患者,实施Wheat、David、Bentall及全弓置换和支架象鼻术等术式。根据术式分别采用常规中低温体外循环,深低温停循环(DHCA)加选择性顺行性脑灌注(SACP)等体外循环灌注方法。其中,主动脉全弓置换术均行右锁骨下动脉与右心房插管建立体外循环,在DHCA加SACP下完成主动脉远端支架植入及弓部血管吻合,期间脑灌注流量5～10ml.kg-1.min-1。术中采用单泵双管及单侧选择性脑灌注、α+pH稳态和高氧血气管理及超滤等技术。结果:体外循环转流时间(197.3±28.3)min、深低温停循环时间(25.3±3.8)min、SACP时间(45.2±7.7)min、心肌阻断时间(86.1±10.8)min。重症监护室时间72～516(181.31)h。院内死亡17例(死亡率11.25%),余134例均痊愈出院,出院时心功能NYHAⅠ～Ⅱ级。结论:正确选择体外循环方法及良好的体外循环管理是Stanford A型主动脉夹层手术成功的保障。主动脉全弓替换术中采用单泵双管及单侧选择性脑灌注、α+pH稳态和高氧血气管理及超滤等技术切实可行,临床预后满意。     

One-stage repair of cardiac and arch anomalies without circulatory arrest

Between 1999 and 2002, 23 patients underwent single-stage complete repair of cardiac anomalies and aortic arch obstruction, without circulatory arrest. Median age was 1.2 years. Intracardiac defects included ventricular septal defect in 9, double-outlet right ventricle in 6, d-transposition of the great arteries and ventricular septal defect in 2, subaortic obstruction in 3, and atrial septal defect in 3. Fourteen patients had coarctation of the aorta, 6 had coarctation with hypoplastic aortic arch, and 3 had interrupted aortic arch. Simple techniques were employed such as cannulation of the ascending aorta near the innominate artery and maintaining cerebral and myocardial perfusion. After correction of arch obstruction, intracardiac repair was undertaken. The mean cardiopulmonary bypass time was 169 min, aortic crossclamp time was 51 min, and arch repair took 16 min. There was no operative mortality or neurological deficit. In follow-up of 1-43 months, no patient had residual coarctation. This simplified technique avoids additional procedures, reduces ischemic time, and prevents problems related to circulatory arrest.     

低温停循环选择性脑灌注在婴幼儿主动脉弓缩窄Ⅰ期根治手术中的应用

目的:总结低温停循环(HCA)结合选择性脑灌注(ASCP)技术在婴幼儿主动脉弓缩窄合并心内畸形手术中体外循环方法。方法:回顾性分析北京安贞医院2009年1月至2010年8月22例婴幼儿主动脉弓缩窄合并心内畸形,行一期主动脉弓重建患者的临床资料。患者年龄平均13个月(16 d～8岁),体质量3～22 kg,平均(7.2±3.1)kg。全部病例温度均降至鼻咽温22.5℃～26.4℃,直肠温度降至24℃～28℃,在手术中所有患者采用HCA,通过无名动脉进行ASCP(20～30 mL/kg)的体外循环方法。心肌保护均采用一次性低温康斯特器官保护液(HTK液)。所有患者均采用术中常规超滤(CUF)及术后改良超滤(MUF)。结果:所有患者均无与体外循环相关的神经系统并发症,无死亡。体外循环时间65～170 min,平均(135±20)min,主动脉阻断时间16～95 min,平均(62±14)min,ASCP时间10～50 min,平均(28±8)min,自动复跳率100%。患儿术后常规镇静,清醒时间6～90 h,平均(44±22)h,机械通气时间8～96h,平均(47.5±20)h,ICU滞留时间1～11 d,平均(4.9±2.5)d,住院时间10～58d,平均(30±11.4)d。结论:在婴幼儿主动脉弓缩窄合并心内畸形主动脉弓重建手术中,应用低温停循环选择性脑灌注的体外循环方法,对于患儿重要器官的保护是安全可行的。     

Selective cerebral perfusion via right axillary artery direct cannulation for aortic arch surgery

BACKGROUND: The risk of neurological complications is still a life-threatening event for patients undergoing proximal aortic arch or total aortic arch surgery. To prevent these complications, axillary artery cannulation and antegrade selective cerebral perfusion were utilized. We compared the effects of using hypothermic circulatory arrest (HCA) alone or with selective cerebral perfusion (SCP/AX) via right side axillary artery direct cannulation. METHODS: 120 patients, mean age 61 +/- 12 years (range 26 - 80), underwent proximal aortic or total aortic arch replacement between 1999 and 2004; 46 were female. We retrospectively compared the results of the two patient groups comparable for preoperative risk factors: 71 pts were operated using HCA beginning in 1999 and 49 pts using HCA/SCP via axillary artery direct cannulation since 2002. The indication for surgery was an aortic aneurysm in 80 (67 %) patients and aortic dissection in 36 (30 %) patients. The groups were well matched with regard to median age (60 vs. 62 yrs), urgency (emergent/urgent 36 vs. 44 %; elective 64 vs. 65 %), and several other known risk factors ( p = ns). RESULTS: Overall in-hospital mortality was 13 %: 10 % with HCA vs. 6 % with SCP/AX. Permanent neurological dysfunction occurred in 10 % with HCA vs. 6 % with SCP/AX. Transient neurological dysfunction (TND) in patients surviving without stroke was lower with SCP/AX (10 %) than with HCA (17 %) ( p = ns). Mean duration of HCA was 28 +/- 12 min when isolated HCA was used, and significantly shorter with 21 +/- 6 min when the combination of SCP/AX ( p = 0.03) was used. Mean duration of CPB was 202 +/- 55 min with HCA vs. 192 +/- 50 min with SCP/AX ( p = ns). Comparison of the groups who had comparable preoperative risk factors showed a trend towards lower in-hospital mortality, stroke and TND rates, a significant reduction in cardiac ( p = 0.034), infectious ( p = 0.025) and bleeding complications ( p = 0.04) in SCP/AX compared with HCA, as well as a significantly shorter duration of hospitalization ( p = 0.046) and shorter ICU stay ( p = ns). CONCLUSION: Our results suggest that HCA/SCP is superior to HCA alone for preventing cerebral injury during operations on the aortic arch. By reducing embolic risk, as well as the duration of HCA, SCP with axillary artery direct cannulation may be the optimal technique for averting cerebral events, reducing complications, and shortening hospital stays following aortic arch repair.     

Comparison of standard external CPR, open-chest CPR, and cardiopulmonary bypass in a canine myocardial infarct model

STUDY OBJECTIVES: After cardiac arrest, open-chest CPR (OCCPR) and cardiopulmonary bypass (CPB) have demonstrated higher resuscitation rates when compared individually with standard external CPR (SECPR). We compared all three techniques in a canine myocardial infarct ventricular fibrillation model. TYPE OF PARTICIPANTS: Twenty-six mongrel dogs were block-randomized to receive SECPR and advanced life support (nine), CPB (nine), or OCCPR (eight). DESIGN AND INTERVENTIONS: All dogs received left anterior descending coronary artery occlusion followed by four minutes of ventricular fibrillation without CPR and eight minutes of Thumper CPR. At 12 minutes, dogs received one of three resuscitation techniques. After resuscitation, all animals received four hours of intensive care. Animals that were resuscitated had histochemical determination of ischemic and necrotic myocardial areas. MEASUREMENTS: Intravascular pressures were measured and coronary perfusion pressure was calculated during baseline, cardiac arrest, resuscitation, and postresuscitation periods. Percent necrotic myocardium, percent ischemic myocardium, and necrotic-to-ischemic ratios were determined for resuscitated animals. Epinephrine dosage and number of countershocks were determined for each group. MAIN RESULTS: Nine of nine CPB and six of nine OCCPR, compared with two of eight SECPR animals, were resuscitated (P less than .01). Three of nine CPB and OCCPR and two of eight SECPR dogs survived to four hours (P = NS). Coronary perfusion pressure two minutes after institution of technique was significantly higher with CPB (75 +/- 37 mm Hg) and OCCPR (56 +/- 31 mm Hg) than in SECPR animals (16 +/- 16 mm Hg, P less than .04). Epinephrine required for resuscitation was significantly less with CPB (0.10 +/- 0.02 mg/kg) than for SECPR (0.28 +/- 0.11 mg/kg, P less than .002). The ratio of necrotic to ischemic myocardium at four hours was significantly lower with CPB (0.15 +/- 0.31) and OCCPR (0.39 +/- 0.25) than for SECPR (1.16 +/- 0.31, P less than .02). CONCLUSION: OCCPR and CPB produce higher coronary perfusion pressures and improved resuscitation rates from ventricular fibrillation when compared with SECPR in this canine myocardial infarct cardiac arrest model. CPB and OCCPR yielded similar resuscitation results, although less epinephrine was required with CPB.     

选择性脑灌注在主动脉手术中的应用

目的探讨中低温选择性脑灌注在主动脉手术应用的安全性及优越性。方法回顾性分析2006年1月～2009年6月在广东省人民医院行升主动脉和主动脉弓手术的108例患者[根据脑保护方法的不同分为深低温停循环组(32例)、深低温选择性脑灌注组(35例)、中低温选择性脑灌注组(41例)]的临床资料、体外循环方法和时间、病死率及并发症发生率等,并进行统计学分析。结果中低温选择性脑灌注组体外循环时间低于深低温停循环组和深低温选择性脑灌注组,差异有统计学意义[(184.56±24.01)min vs.(216.94±25.22)min vs.(200.09±23.80)min,P<0.05];再次开胸率也低于其他两组,差异有统计学意义[4.9%(2/41) vs.14.3%(5/35) vs.25.0%(8/32),P<0.05]。术后呼吸功能不全、肾功能衰竭、感染、腹部并发症和截瘫的发生率比较,差异无统计学意义(P>0.05)。3组住院病死率、一过性和永久性神经系统并发症的发生率比较,差异无统计学意义(P>0.05)。结论中低温选择性脑灌注是一种安全有效的脑保护方法,缩短了体外循环时间,降低了术后再次开胸率。     

股动脉和腋动脉插管应用于主动脉弓部手术的结果比较

目的 比较股动脉和腋动脉插管在成人主动脉弓部手术中的应用及结果比较。 方法 选取行主动脉弓部手术患者58例，根据术中采用的插管方式分为股腋动脉两组，分别记录两组患者一般情况、手术方式、体外循环转流时间、主动脉阻断时间、脑灌注时间、术后清醒时间、气管插管时间、重症监护室（intensive care unit,ICU）住院时间、术后心功能恢复、插管相关并发症和术后出现认知功能障碍等情况。 结果 两组共计3例患者死亡,其余患者均痊愈出院，两组患者一般情况及主动脉阻断时间股动脉组（113±18）min、腋动脉组（117±16）min；脑灌注时间股动脉组（25±6）min、腋动脉组（25±6）min、两组体外循环转流时间股动脉组（266±24）min、腋动脉组（267±24）min患者术后清醒时间股动脉组（37±26）h、腋动脉组(38±26)h；气管插管时间股动脉组（64±6）h、腋动脉组（63±7）h；重症监护室住院时间股动脉组（8.5±2.1）d、腋动脉组（8.1±2.2）d、休克的发生率、插管相关并发症发生率及术后出现认知功能障碍的差异均无统计学意义。 结论 股动脉和腋动脉插管对行主动脉弓部手术患者术后脑部并发症及插管相关并发症的发生无显著差异。     

Profound hypothermic circulatory arrest in management of aortic aneurysms

A total of 15 patients having aneurysms of aorta were operated from June 1997 to December 1998 using deep hypothermic circulatory arrest as a modality of brain protection. There were 12 males and 3 females. The age ranged from 19 years to 74 years and the mean age was 44.9 years. Nine patients had aneurysms of ascending aorta (group I), one had aneurysm of ascending aorta and arch of aorta (group II), four had aneurysm of the distal aortic arch (group III) and one patient had thoracoabdominal aortic aneurysm (group IV). In group I, six patients underwent Bentall procedure, two underwent Wheat procedure and one patient had repair of pseudoaneurysm of ascending aorta. The only patient in group II had his ascending aorta and arch replaced, with reimplantation of left common carotid and innominate artery. In group III, three patients had interposition Gelseal graft and one had repair of the tear in distal aortic arch. The lone patient in group IV had interposition Gelseal graft of thoracoabdominal aorta. The hypothermic circulatory arrest was used in all of them for brain and/or spinal cord protection. Retrograde cerebral perfusion was used in two patients. There were two (13%) operative deaths. One patient died of cerebrovascular accident on eighth post-operative day and second died of inadequate surgical repair. There was one instance of left hemiparesis secondary to an infarct in right frontoparietal region. To conclude, hypothermic circulatory arrest could provide an adequate brain protection for aortic aneurysm surgery. Retrograde cerebral perfusion could be an adjuvant when the anticipated time of hypothermic circulatory arrest is likely to exceed 45 minutes.     

Beating heart surgery and left ventricular dysfunction

We report our experience with systematic coronary revascularization on the beating heart among patients with left ventricular dysfunction as defined by a left ventricular ejection fraction < or = 40%. Between September 1996 and April 2000, 500 off-pump (OPCAB) revascularizations were performed (95% of all revascularizations for the same time frame, single surgeon). Among them, 76 patients qualified as left ventricular dysfunction and were compared to a similar cohort of 237 patients operated on with cardiopulmonary bypass (CPB) during the same time frame. Age and sex distribution, average preoperative left ventricular ejection fraction and incidence of preoperative unstable angina were the same for both groups. On average, 3.04 +/- 0.89 and 2.97 +/- 0.69 grafts/patient were made in the OPCAB and CPB groups respectively (p = NS). Complete revascularization was achieved in 95% of the OPCAB group. Incidence of preoperative intra-aortic balloon assistance were higher in OPCAB (22% versus 9%, p = 0.005) whereas postoperative need for new intra-aortic balloon assistance was higher in CPB (8% versus 0%, p = 0.02). Incidence of postoperative myocardial infarction was comparable in both groups (6.5% versus 5.5%). Maximal creatinine phosphate of myocardial origin were lower in OPCAB group (beating heart: 32 +/- 52%, cardiopulmonary bypass: 45 +/- 51%, p = 0.055). Operative mortality was lower in OPCAB group although it did not reach statistical significance (beating heart: 2.6% versus cardiopulmonary bypass: 4.6%, p = 0.3). Complete coronary revascularization on the beating heart can be achieved in patients with left ventricular dysfunction with excellent outcome and low operative mortality.     

Randomized controlled trial of the effects of remote ischemic preconditioning on children undergoing cardiac surgery: first clinical application in humans.

OBJECTIVES: We conducted a randomized controlled trial of the effects of remote ischemic preconditioning (RIPC) in children undergoing repair of congenital heart defects. BACKGROUND: Remote ischemic preconditioning reduces injury caused by ischemia-reperfusion in distant organs. Cardiopulmonary bypass (CPB) is associated with multi-system injury. We hypothesized that RIPC would modulate injury induced by CPB. METHODS: Children undergoing repair of congenital heart defects were randomized to RIPC or control treatment. Remote ischemic preconditioning was induced by four 5-min cycles of lower limb ischemia and reperfusion using a blood pressure cuff. Measurements of lung mechanics, cytokines, and troponin I were made pre- and postoperatively. RESULTS: Thirty-seven patients were studied. There were 20 control patients and 17 patients in the RIPC group. The mean age and weight of the RIPC and control patients were not different (0.9 +/- 0.9 years vs. 2.2 +/- 3.4 years, p = 0.4; and 6.9 +/- 2.9 kg vs. 11.5 +/- 10 kg, p = 0.06). Bypass and cross-clamp times were not different (80 +/- 24 min vs. 88 +/- 25 min, p = 0.3; and 55 +/- 13 min vs. 59 +/- 13 min, p = 0.4). Levels of troponin I postoperatively were greater in the control patients compared with the RIPC group (p = 0.04), indicating greater myocardial injury in control patients. Postoperative inotropic requirement was greater in the control patients compared with RIPC patients at both 3 and 6 h (7.9 +/- 4.7 vs. 10.9 +/- 3.2, p = 0.04; and 7.3 +/- 4.9 vs. 10.8 +/- 3.9, p = 0.03, respectively). The RIPC group had significantly lower airway resistance at 6 h postoperatively (p = 0.009). CONCLUSIONS: This study demonstrates the myocardial protective effects of RIPC using a simple noninvasive technique of four 5-min cycles of lower limb ischemia and reperfusion. These novel data support the need for a larger study of RIPC in patients undergoing cardiac surgery.     

Antegradely insertable aortic balloon occlusion catheter for aortic arch repair

 We have developed an antegradely insertable aortic balloon occlusion catheter for aortic arch repair, and review our experiences of using it. The purpose of the present study was to examine the usefulness of the balloon for surgical treatment of aortic arch aneurysm. In 30 patients with aortic arch aneurysm, including 22 with a non-ruptured and 8 with a ruptured aneurysm, the catheter was antegradely inserted into the descending thoracic aorta through the aortic arch or the aneurysm without opening the pleural space after establishing antegrade selective cerebral perfusion and obtaining cardiac arrest. During distal anastomosis, the catheter occluded the aorta with continuous perfusion of the lower half of the body through an arterial cannula inserted into the femoral artery. Among the patients with a nonruptured aneurysm, two deaths (9.1%) occurred because of aorto-broncho-esophageal fistulae or cardiac arrest due to severe asthma attack within 30 days, and the other three hospital deaths were due to aspiration pneumonia, multiple organ failure with preoperative renal dysfunction, or low cardiac output syndrome due to perioperative myocardial infarction. Among the patients with a ruptured aneurysm, three deaths (37.5%) were due to acute myocardial infarction, respiratory failure, or intractable arrhythmia within 30 days, and another hospital death was caused by mediastinitis. No paraplegia was caused in any patient excluding one of the patients with a ruptured aneurysm who could not be weaned from the extracorporeal circulation due to perioperative myocardial infarction. There was no early postoperative serious visceral organ dysfunction except for two patients with postoperative low cardiac output syndrome or preoperative severe renal dysfunction. This catheter was effective in protecting the visceral organs and the spinal cord in the repair of an aortic arch aneurysm. Received: March 7, 2002 / Accepted: November 29, 2002     

Femoral artery cannulation as a safe alternative for aortic dissection arch repair in the era of axillary artery cannulation

BackgroundTo evaluate the safety and efficacy of femoral artery cannulation as an alternative to axillary artery cannulation, we retrospectively compared outcomes between patients with axillary or femoral artery cannulation during open aortic arch repair for type A aortic dissection (TAAD).MethodsBetween January 2014 and January 2019, 646 patients underwent open aortic arch repair with circulatory arrest for TAAD using antegrade selective cerebral perfusion (SACP) and were divided into two groups according to the site of arterial cannulation: an axillary artery group (axillary group, n=558) or a femoral artery group (femoral group, n=88). The axillary artery was considered as the primary cannulation site, and the femoral artery was used as an alternative when axillary artery cannulation was deemed unsuitable or had failed. Propensity score matching was performed to correct baseline differences.ResultsAfter propensity score matching, the patients’ characteristics were comparable between groups (n=85 in each). The incidence of in-hospital mortality (10.6% vs. 14.1%; P=0.642) and stroke (3.5% vs. 5.9%; P=0.720) were comparable between the axillary and femoral groups. The incidence of newly required dialysis was lower in the femoral group, but the difference was not statistically significant (34.1% vs. 20.0%; P=0.050). Other outcomes and major adverse events were comparable.ConclusionsFemoral artery cannulation produced similar perioperative outcomes to axillary cannulation after open arch repair for TAAD. The femoral artery can be used as a safe and effective alternative to the axillary artery for arterial cannulation in TAAD patients undergoing open arch repair.     

缺血后处理对改善老年人急性心肌梗死再灌注损伤心肌血流灌注的疗效分析

目的 探讨缺血后处理对老年急性ST段抬高型心肌梗死(STEMI)患者再灌注损伤的保护作用。 方法 连续选择发病12h内行直接经皮冠状动脉介入治疗(PCI)的急性STEMI患者215例,数字抽签法随机分为缺血后处理组和常规治疗组（对照组）,两组年龄65岁及以上患者分别为38例和46例。对照组给予单纯再灌注治疗,缺血后处理组采用再灌注30 s,再缺血30 s,交替3次后再持续灌注的方法。分别评估缺血后处理对老年患者再灌注心律失常的发生率、冠状动急性心肌梗死溶栓试验(TIMI)血流分级和心肌组织水平灌注等指标的影响。 结果 缺血后处理组和对照组再灌注心律失常发生率分别为21.1％(8/38)和45.7％(21/46),差异有统计学意义(x2=5.571,P＜0.05);其中高危、需要药物或电转复及临时起搏等干预的心律失常发生率分别为7.9％(3/38)和26.1％(12/46),差异有统计学意义(x2=4.695,P＜0.05)。校正的TIMI血流帧数(cTFC)分别为(23.6±3.7)帧和（26.1±5.9）帧(t=5.434,P＜0.05)。TIMI心肌灌注分级(TMPG)3级分别为89.5％（34例）和69.6％（32例）,差异有统计学意义（x2=4.899,P＜0.05）。 结论 心肌缺血后处理能减轻老年STEMI患者心肌再灌注损伤,可应用于老年人STEMI再灌注损伤的防治。     

联系方式：周涛 chowtao@sina.com. Tel:13985024647

目的 探讨浅低温心脏不停跳心内直视手术对体外循环瓣膜置换患者线粒体耦联因子6（CF6）表达的影响.方法 选择2010年1月至2011年11月广西医科大学第一附属医院择期行人工机械瓣膜置换手术患者50例,使用随机数字表法分为心脏停跳组（停跳组,在中度低温心脏停跳下完成心脏瓣膜置换手术）和浅低温心脏不停跳组（不停跳组,在浅低温心脏跳动下完成手术）,每组25例,分别于体外循环转机前（T1）,转机30 min（T2）,开放升主动脉时（T3）,停体外循环后6 h（T4）、24 h（T5）、72 h（T6）、120 h（T7）7个时间点取静脉血,使用放射免疫分析法测定CF6、6-酮-前列环素F1a（6-Keto-PGF1a）的表达.结果 在T2～T5时间点,停跳组CF6浓度（pg/ml）依次为574.3±103.7、855.3±175.8、665.1±95.6、398.9±74.5,较T1时浓度244.5±52.6升高（P＜0.05）;不停跳组CF6浓度（pg/ml）依次为317.1±93.3、673.9±115.1、452.6±81.2、296.2±61.4,较T1时浓度238.4±49.3升高（P＜0.05）;停跳组变化更明显（P＜0.05）.两组均于T6恢复至T1水平.停跳组T2 ～T4时6-Keto-PGF1a浓度（pg/ml）依次为330.7±67.9、435.6±75.8、235.7±35.0,较T1浓度64.3±18.4升高（P＜0.05）;不停跳组T2～T4时浓度（pg/ml）依次为467.4±43.5、573.9±33.1、356.2±41.9,较T1浓度68.3±19.3升高（P＜0.05）;不停跳组升高明显（P＜0.05）.两组均于T5恢复至T1水平.结论 心脏不停跳手术对心肌包括内皮细胞损伤较小是体外循环手术CF6表达上调相对较小的重要原因.CF6的变化可以影响机体前列环素的表达.     

A new technique of myocardial protection during aortic root replacement: antegrade/retrograde coronary perfusion

Aortic root surgery has traditionally been performed with an arrested and cooled heart using cardioplegia. A new technique of myocardial protection was utilized in the treatment of ascending aortic aneurysm with severe aortic valve regurgitation requiring aortic root replacement with the Cabrol technique. Retrograde and antegrade perfusion of the heart with blood allowed the surgical operation to be performed safely while the heart was beating and eliminated the ischemic reperfusion injury which occurs during cardioplegic arrest and reinstitution of blood perfusion after removal of the aortic cross-clamping required in traditional techniques.     

累及弓部分支血管的A型主动脉夹层全弓置换手术

目的 观察累及弓部分支血管的A型主动脉夹层（AAD）全弓置换手术效果。方法 将2010年1月~2015年12月于我中心治疗的68例夹层累及弓部血管的AAD患者设为弓部组,并抽取同期弓部血管正常的60例AAD患者作为对照组。弓部组中33例患者术前伴脑部症状,包括昏迷2例,一过性意识丧失6例,嗜睡、语言和感觉障碍等25例（症状组）;35例患者未见明显脑部症状（无症状组）。两组患者均行AAD全弓置换手术治疗。观察以下术中和术后指标,包括:症状组和无症状组选择性顺行脑灌注(ACP)时间,弓部破口、永久性神经功能缺损（PND）和一过性神经功能缺损(TND)和院内死亡例数以及出院前NIHSS评分;弓部组和对照组手术中情况:包括手术时间、体外循环时间、ACP时间、心脏停搏时间,以及双侧选择性顺行脑灌注（BACP）和单侧选择性顺行脑灌注（UACP）例数,主动脉病变情况包括中度以上主动脉瓣返流（AR）、弓部破口例数;弓部组和对照组手术后恢复情况,包括ICU时间,再次开胸止血、长期机械通气、血滤治疗、气管切开、肺部感染、PND、TND和院内死亡例数。结果 全部AAD患者均完成手术操作,症状组和无症状组患者ACP时间无显著差异;与无症状组比较,症状组患者术中探查破口位于主动脉弓部、PND和TND例数以及院内死亡发生例数较多,患者出院前NIHSS评分较高（P<0.05）。弓部组和对照组患者在术中BACP和UACP方式选择、术中探查中度以上AR例数上无显著差异。与对照组比较,弓部组手术和体外循环时间、ACP和心脏停搏时间较长,术中探查破口位于主动脉弓部例数较多（P< 0.05,P<0.01）。两组患者再次开胸止血、气管切开、肾功能不全血滤治疗及院内死亡例数无显著差异。与对照组比较,弓部组患者ICU滞留时间较短,长期机械通气、肺部感染、PND和TND例数较多（P<0.05,P<0.01）。结论 累及弓部分支血管的AAD患者手术操作复杂,全弓置换术后脑部并发症发生率较高,其中术前存在脑部症状者手术风险更大。     

Abnormal thallium kinetics in postoperative coarctation of the aorta: evidence for diffuse hypertension-induced vascular pathology

After operative correction of congenital coarctation of the aorta, patients continue to have excess cardiovascular mortality, including manifestations of ischemic heart disease. Previous morphologic studies support the concept of direct hypertensive vascular injury in these patients. To determine whether abnormalities of myocardial perfusion were present in an asymptomatic group of patients with coarctation repair, 18 men and 9 women with a mean age of 26 years (range 19 to 41) were studied between 2 and 25 years after operative correction. Stress electrocardiography and quantitative thallium imaging by a circumferential profile technique were used. These patients were compared with a normal group, statistically defined as having a less than 1% prevalence of significant obstructive coronary artery disease. The postoperative coarctation group demonstrated a reduction in global thallium redistribution in each view analyzed. As compared with findings in the control subjects, thallium washout in the anterior view (41.9 versus 48.6%, p = 0.02) and left anterior oblique projection (40.5 versus 48.2%, p = 0.007) was significantly diminished. Although the postoperative coarctation group had a lower thallium redistribution rate in the lateral view (41.4 versus 46.3%, p = 0.09) this difference did not reach statistical significance because of the intrinsic variability of this projection. Plots of the median percent thallium washout revealed independence from circumferential profile angle, indicating global abnormalities in perfusion. No correlation between clinical variables and thallium kinetics could be established, suggesting marked individual variability in the development of this vascular lesion. The observation of abnormal thallium kinetics in patients with coarctation repair may have consequences for long-term follow-up and therapy.     

Nitric oxide inhalation improves microvascular flow and decreases infarction size after myocardial ischemia and reperfusion.

OBJECTIVES: The purpose of this study was to test if nitric oxide (NO) could improve microvascular perfusion and decrease tissue injury in a porcine model of myocardial ischemia and reperfusion (I/R). BACKGROUND: Inhaled NO is a selective pulmonary vasodilator with biologic effects in remote vascular beds. METHODS: In 37 pigs, the midportion of the left anterior descending coronary artery was occluded for 50 min followed by 4 h of reperfusion. Pigs were treated with a saline infusion (control; n = 14), intravenous nitroglycerin (IV-NTG) at 2 microg/kg/min (n = 11), or inhaled nitric oxide (iNO) at 80 parts per million (n = 12) beginning 10 min before balloon deflation and continuing throughout reperfusion. RESULTS: Total myocardial oxidized NO species in the infarct core was greater in the iNO pigs than in the control or IV-NTG pigs (0.60 +/- 0.05 nmol/mg tissue vs. 0.40 +/- 0.03 nmol/mg tissue and 0.40 +/- 0.02 nmol/mg tissue, respectively; p < 0.01 for both). Infarct size, expressed as percentage of left ventricle area at risk (AAR), was smaller in the iNO pigs than in the control or IV-NTG pigs (31 +/- 6% AAR vs. 58 +/- 7% AAR and 46 +/- 7% AAR, respectively; p < 0.05 for both) and was associated with less creatine phosphokinase-MB release. Inhaled NO improved endocardial and epicardial blood flow in the infarct zone, as measured using colored microspheres (p < 0.001 vs. control and IV-NTG). Moreover, NO inhalation reduced leukocyte infiltration, as reflected by decreased cardiac myeloperoxidase activity (0.8 +/- 0.2 U/mg tissue vs. 2.3 +/- 0.8 U/mg tissue in control and 1.4 +/- 0.4 U/mg tissue in IV-NTG; p < 0.05 for both) and decreased cardiomyocyte apoptosis in the infarct border zone. CONCLUSIONS: Inhalation of NO just before and during coronary reperfusion significantly improves microvascular perfusion, reduces infarct size, and may offer an attractive and novel treatment of myocardial infarction.