THIRTY YEARS EXPERIENCE WITH HEART VALVE SURGERY: ISOLATED MITRAL VALVE REPLACEMENT

Background : Thirty years have elapsed since the commencement of open-heart surgery in South Australia. A retrospective study was performed to evaluate mortality and complication rates and to identify factors associated with poor outcomes in all patients who underwent prosthetic mitral valve replacement during this period. Methods : Questionnaires and personal contact have been used to generate a combined database of pre-operative and postoperative information and long-term follow-up on 938 patients who underwent isolated prosthetic mitral valve replacement at the Cardio-Thoracic Surgical Unit of the Royal Adelaide Hospital between 1963 and 1993. Results : Complete survival follow-up data were obtained for 92% (865) of the patients. The Starr-Edwards valve was used in 95% (891) of the patients, a Bjork-Shiley prosthesis in 2.5% (23) of the patients, and only 24 (2.5%) other valves were inserted. The hospital mortality rate for the 30-year period was 4.7%. The mean age of the patients who underwent surgery was greater in each of the three successive decades. A long-term survival advantage was observed for patients with mitral stenosis, however, survival was significantly shorter for patients with higher New York Heart Association (NYHA) functional classifications and for patients in pre-operative atrial fibrillation. Pre-operative dyspnoea was significantly improved following mitral valve replacement. The rates of postoperative haemorrhagic and embolic complications were low by comparison with other published series. Conclusion : Mitral valve recipients do not regain a normalized life expectancy, but risk factors that determine long-term survival can be identified pre-operatively to aid appropriate patient selection.     

MANAGEMENT OF ASCENDING AORTIC DISSECTION: EXPERIENCE WITH THE USCI* INTRALUMINAL PROSTHESIS AND A METHOD OF AORTIC VALVE REPAIR

Ten consecutive cases of acute ascending aortic dissection operated on using the usci intraluminal prosthesis from 1983 to 1986 were reviewed. Diagnosis was achieved by conventional angiography in six cases, by intra-arterial digital subtraction angiography in one case, by computerized tomography (ct) scan in two cases and by echocardiography and abdominal ultrasound in one case. An entry site was seen in only five out of six conventional angiograms. At operation six of the 10 had a degree of tamponade. Aortic regurgitation was seen five times, due to dissection in four cases and to marian's disease in one. The entry site was controlled in eight cases. Repair using intraluminal prosthesis only was achieved in five cases. Aortic valve repair was added in four out of 10 cases, and in one of these an aorta-to-right coronary graft was also added. One case required aortic valve replacement. A method of aortic valve repair is presented. There were nine survivors, 1–36 months postoperatively. Of these, eight were asymptomatic on no medication. One had severe aortic regurgitation noted 2 months postoperatively and has mildly reduced exercise tolerance. Surgical treatment can be planned if the presence of dissection is proven and involvement of the ascending aorta is demonstrated. Early surgery is important, since six of the 10 cases in this series had tamponade. The intraluminal graft will reliably redirect flow to the true lumen and exclude the dissection from the pericardium. Aortic valve repair can be successful though late replacement may be necessary in some cases. Control of the entry site is not essential to achieve a good clinical result.     

MONOCUSP AORTIC VALVE REPLACEMENT IN DOGS: AN EXPERIMENTAL MODEL

Aortic valve replacement using human allograft valves is a well established procedure, following which histological evidence of a host-graft interaction is seen .This varies in intensity, depending on the types of sterilizing and storage agents to which the allograft is exposed prior to insertion. A canine experimental model which enables study of these tissue ingrowth patterns in variously treated allografts has been devised. The technique is described in detail.     

心脏瓣膜替换术中紧急问题的处理

心脏瓣膜替换术中的紧急问题系指心脏瓣膜病变的病人送入手术室至关胸完毕准备送入监护病房期间发生危及病人生命的紧急外科问题。作者根据本单位的临床经验及体会，对心脏瓣膜替换中心搏聚停，左室破裂，空气栓塞，人工瓣膜急性功能障碍等紧急问题发生的原因，处理及其预防进行了讨论。     

无支架带腱索支持生物心脏瓣膜的研究

为研制无支架带腱索支持生物心脏瓣膜并对其血流动力学及抗钙化性能进行评价,试验选用年幼绵羊9只,新鲜牛心包经98％甘油鞣制后,缝制成21mm无支架生物瓣,在常温体外循环下行绵羊二尖瓣替换。术后不抗凝,2～8个月后择期行心导管,左室造影及病理检查。结果表明:全组无血栓、栓塞或感染。8例于术后168.4±55.3天,经血流动力学检测:平均跨瓣压差0.76±0.20kPa,有效瓣口面积1.9±0.75cm~2,心脏指数104.1±38.7ml/kg/min;瓣膜无关闭不全或轻度关闭不全者各3例,中度关闭不全者2例。瓣膜病理检查:仅2例有中度钙化,6例轻度钙化。电镜扫描示7例有内皮细胞覆盖生长。1例于术后220天死于心衰,为瓣膜交界处缝线松脱,产生关闭不全所致;其瓣膜表面光泽、柔软,无任何增厚或钙化灶。提示该无支架带腱索支持生物心脏瓣膜的血流动力学及抗钙化性能均满意。     

去细胞猪主动脉瓣叶的获取和内皮细胞的种植

目的　探讨猪主动脉瓣叶去细胞后作为组织工程心脏瓣膜支架的可行性。　方法　经胰酶 - EDTA、表面活性剂和核酸酶处理 ,去除猪主动脉瓣叶的细胞成分 ,测定瓣叶去细胞前、后的生物力学特性 ,并在其表面种植新生牛主动脉内皮细胞 (BAECs) ;分别行大鼠皮下包埋实验。　结果　猪主动脉瓣叶中的细胞成分能完全去除 ,获得完整无细胞的纤维网状支架 ,断裂强度和断裂伸长率无明显变化 ;种植的 BAECs在去细胞瓣叶表面可形成一层连续的细胞层 ,其分泌前列环素 (PGI2 )的能力同直接种植在 2 4孔板中的比较 ,差异无统计学意义 (P>0 .0 5 )。　结论　猪主动脉瓣去细胞后获得的纤维支架可以用来构建组织工程瓣膜 ,适宜于血管内皮细胞的生长。     

强调手术技巧及围手术期管理可降低二尖瓣、主动脉瓣双瓣置换术死亡率

1993年1月至1996年12月,作者等对120例患者施行了二尖瓣和主动脉瓣双瓣联合置换术,占同期瓣膜手术的41％。其中117例为风湿性心脏病,3例为瓣膜退行性病变。45例患者同时接受了三尖瓣成形术(44例De Vega成形、1例Carpentier环成形),2例患者接受了三尖瓣置换术,1例患者接受了冠状动脉搭桥术。术后早期死亡3例(死亡率2.5％),低于同期瓣膜置换术的总体死亡率(3.8％)。其余117例患者中虽然也出现了一些并发症如出血、脏器功能不全、感染等,但术后恢复相对平稳,术后平均21天痊愈出院。为了降低手术死亡率,除了重视术前准备、加强围术期管理和改善体外循环灌注和心肌保护技术以外,强调在术中要尽量保持二尖瓣与左心室的连续关系、积极处理三尖瓣病变、必要时积极扩大主动脉瓣环。     

经导管主动脉瓣植入术治疗重度主动脉瓣狭窄

目的 观察经导管主动脉瓣植入术（TAVI）治疗重度主动脉瓣狭窄（AS）的效果。方法 回顾性收集18例接受TAVI的重度AS患者,记录TAVI即刻成功率,观察治疗过程中及治疗后相关并发症;随访记录治疗后1、3个月瓣膜功能及心血管事件。结果 18例实施TAVI成功。对3例AS合并冠心病患者行一站式TAVI+经皮冠状动脉介入治疗,对2例冠状动脉阻塞高风险患者通过“烟囱”或“开窗”技术加以预保护。1例顽固性心力衰竭患者接受体外膜氧合器辅助下TAVI;1例尿毒症患者于TAVI前、后接受血液透析。TAVI即刻成功率100%（18/18）。TAVI过程中1例发生心脏压塞而转外科治疗;1例因中度瓣周漏而植入另1枚瓣膜。治疗后3例存在轻度瓣周漏,1例因三度房室传导阻滞而植入永久性心脏起搏器。未见严重并发症。治疗后即刻及1、3个月,超声心动图显示主动脉瓣口流速［（203.47±70.65）、（219.64±67.49）、278.00（188.50,289.00）cm/s］和跨瓣压差［（17.16±14.05）、0（0,20.50）、12.00（0,32.50）mmHg］均较治疗前［470.50（428.75,553.25）cm/s、79.50（53.25,112.50）mmHg］降低（P均＜0.05）。治疗后3个月内无死亡、卒中、急性冠脉综合征及新发房颤等严重心血管事件发生。结论 TAVI治疗重度AS安全,且短期疗效好。     

经导管心脏瓣膜研究进展

经导管主动脉瓣置换术已成为治疗严重主动脉瓣狭窄的主要方式,目前市售瓣膜主要包括球囊可膨胀瓣膜和自膨胀瓣膜。新一代球囊可膨胀瓣膜由SAPIEN XT和SAPIEN 3瓣膜组成,最新自膨胀瓣膜为可重新定位的Evolut Pro系统。本文对经导管心脏瓣膜研究进展进行综述。     

重症心不停搏双瓣置换术

本文介绍了心不停搏双瓣置换术的体外循环及手术技术。特别强调：①体外循环流量必须维持平均动脉压大于6.7kpa，预充液内加入少量去甲肾上腺素（1μm/kg）有助于提高灌注压。②33℃浅低温有利于心脑等重要脏器保护和手术操作。③主动脉瓣转换时，冠状静脉窦送行灌注流量在200-300ml/min之间。④左心术毕，注意充气排气。     

MORBIDITY AND MORTALITY AFTER ABDOMINAL AORTIC SURGERY IN A POPULATION OF PATIENTS WITH HIGH CARDIOVASCULAR RISK

Postoperative myocardial infarction is a major risk factor in patients undergoing abdominal aortic surgery. Correction of cardiac ischaemia prior to abdominal aortic surgery improves outcome. The morbidity and mortality of 639 consecutive patients were reviewed from an area with poor access to cardiac surgery, operated upon in a single tertiary referral hospital for aortic aneurysm or aortobifemoral grafting. A total of 101 patients with ruptured aortic aneurysm who survived to reach the intensive care unit experienced a hospital mortality of 29%. Multiorgan failure was the cause of death in 48% and postoperative myocardial infarction in 31%. Of the 253 patients with intact aortic aneurysm, which included elective and urgent resection, the mortality was 9%. There was a high incidence of uncorrected pre-operative ischaemic heart disease and myocardial infarction was the major cause of death (62%). Pre-operative myocardial infarction was predictive of postoperative cardiac morbidity and mortality. Of the 285 patients undergoing aortobifemoral grafting the mortality was 3% despite a high incidence of pre-operative ischaemic heart disease. Further reductions in postoperative death from ruptured aortic aneurysm must await improved screening to diagnose and treat the aneurysm before rupture. In patients operated upon electively, improved pre-operative cardiac screening and coronary bypass grafting where appropriate, especially for patients with aortic aneurysm and previous myocardial infarction, may further reduce pen-operative mortality.     

Lifetime management of aortic valve disease: Aligning surgical and transcatheter armamentarium to set the tone for the present and the future

Transcatheter aortic valve replacement (TAVR) has already received the green light for high-, intermediate- and low-risk profiles and is an alternative for all patients regardless of age. It is clear that there has been a push towards the use of TAVR in younger and younger patients (<65 years), which has never been formally tested in randomized controlled trials but seems inevitable as TAVR technology makes steady progress. Lifetime management as a concept will set the tone in the field of the structural heart. Some subjects in this scenario arise, including the importance of optimized prosthetic hemodynamics for lifetime care; surgical procedures in the aortic root; management of structural valve degeneration with valve-in-valve procedures (TAVR-in-surgical aortic valve replacement [SAVR] and TAVR-in-TAVR) and redo SAVR; commissural alignment and cusp overlap for TAVR; the rise in the number of surgical procedures for TAVR explantation; and the renewed interest in the Ross procedure. This article reviews all these issues which will become commonplace during heart team meetings and preoperative conversations with patients in the coming years.     

PROGNOSTIC FACTORS IN ELECTIVE AORTIC RECONSTRUCTIVE SURGERY

Background : The present study was carried out to determine the risk factors associated with peri-operative mortality and long-term survival in patients undergoing abdominal aortic reconstructive surgery (ARS). Methods : A retrospective review was performed of the case notes of all patients having ARS at a university teaching hospital during a 5.5-year period, and their details entered onto a pro forma. Results : A total of 252 patients underwent ARS between July 1989 and December 1994. The peri-operative mortality was 7.5%. The most frequent adverse events were cardiac events, accounting for 8 (42%) of the peri-operative deaths. The risk of a peri-operative cerebrovascular accident was low (n = 3, 1.2%) as was the risk of peri-operative renal failure requiring dialysis (n = 3, 1.2%). Factors independently linked to increased peri-operative mortality included moderate-to-severe hypertension (P= 0.05, odds ratio = 3.54), those with renal impairment (P= 0.05, odds ratio = 2.69), and blood transfusion requirements (P < 0.001, odds ratio = 1.26). Long-term survival was independently shortened by occlusive disease (P= 0.004, hazard ratio = 2.78) and ischaemic heart disease (P < 0.001, hazard ratio = 3.58). Conclusions : The risks of ARS were significantly increased in patients with severe hypertension, those with renal impairment and those requiring blood transfusion. Long-term survival was shortened for those patients with occlusive aortic disease and ischaemic heart disease. These risk factors should be carefully assessed in each patient before performing elective ARS.     

经导管植入国产自膨式主动脉瓣膜治疗老年性主动脉瓣狭窄(附3例报告)

正75岁以上的老年人退行性心脏瓣膜病发病率高达4.6%~([1])。老年性主动脉瓣狭窄(aortic valve stenosis,AS)发病率越来越高。目前外科主动脉瓣膜置换术(surgery aortic valve replacement,SAVR)仍是治疗重度AS的首选方法,但30%~50%的患者因存在严重合并症、无法承受外科手术而出现心力衰竭和心源性猝死。2002年Cribier等~([2])采用经导管主动     

INFRARENAL AORTIC ANEURYSM SURGERY IN A RURAL SURGICAL SERVICE: RISK FACTORS FOR MORTALITY

Background : An audit of both the emergency and elective abdominal aortic surgery that was performed in a rural surgical service, was carried out. Methods : Retrospective data analysis was performed on 41 patients who were treated for abdominal aortic aneurysms (AAA) during an 8-year period from 1989 to 1996. Postoperative outcomes were analysed with respect to patient age, mode of presentation (elective or emergency), transfusion requirements and pre-existing cardiac and respiratory disease. Univariate analysis was performed using Fisher's exact test, and the odds ratio for adverse outcome was calculated. Results : A postoperative mortality rate of 5.8% in elective repairs and 68% in cases of rupture was noted. Pre-existing respiratory disease, transfusion requirements of more than six units and presentation with retroperitoneal leak or rupture correlated with postoperative mortality, while age and pre-existing cardiac disease were shown not to be predictive of adverse outcome following surgery. Conclusions : An overall improvement in operative outcomes in the institution (Wimmera Base Hospital) that was audited would be affected by earlier referral for elective repair in selected patients. Like others, the authors believe that age on its own is not a contraindication to elective AAA repair.     

ACUTE AORTIC DISSECTION AS A COMPLICATION OF CORONARY ARTERY SURGERY

Acute dissection of the ascending aorta is a rare, potentially fatal complication of cardiac surgery. During surgery patients with long-standing hypertension and atheromatous arterial disease require careful handling and cannulation of the aorta and aggressive intra-operative and postoperative management of aortic pressure. We present the successful treatment of a patient with acute aortic dissection following elective coronary artery surgery.     

ISOLATED CONGENITAL PULMONARY INCOMPETENCE: CASE REPORT AND LITERATURE REVIEW

Although the literature fails to clearly define the prognosis of isolated congenital pulmonary incompetence (ICPI), there are suggestions that the lesion is not necessarily benign. A case report is presented of pulmonary valve replacement for ICPI which reversed not only symptoms but also electrocardiographic manifestations of right ventricular overload. A literature review is included with the case report.