主动脉瓣置换术中人工心脏瓣膜-患者不匹配现象的预防

目的 总结主动脉瓣置换术(AVR)中预防人工心脏瓣膜-患者不匹配(PPM)现象的措施和效果.方法 2010年2月至2011年12月,357例接受主动脉瓣置换术患者参照人工心脏瓣膜的有效开口面积(EOA)和患者的体表面积计算有效开口面积指数(EOAI),将EOAI ＞0.85 cm2/m2定义为不存在或仅有轻度的PPM,0.65≤EOAI≤0.85 cm2/m2定义为中度PPM,EOAI＜0.65 cm2/m2定义为重度PPM.术中采用“三步法”预防PPM.若患者主动脉瓣环过小,则采用以下3种方法:(1)主动脉瓣置换采用单针单线不带垫片间断缝合技术;(2)应用新型人工心脏瓣膜;(3)主动脉瓣环扩大手术.结果 357例AVR,置换机械瓣272例、生物瓣85例.本组49例AVR采用单针单线间断缝合法.38例应用新型人工心脏瓣膜,11例应用主动脉瓣环扩大手术.357例手术的PPM总发生率为6.4％,但无重度PPM发生.置换机械瓣的PPM发生率为1.8％,而生物瓣为21.2％.结论 AVR术中采取适当措施可以有效预防术后PPM现象的发生.     

小主动脉瓣环患者生物瓣与机械瓣置换术后心功能变化的比较

目的分析比较小主动脉瓣环(直径≤21mm)患者人工生物瓣置换与人工机械瓣置换术后心功能的变化,探讨人工生物瓣置换术后是否存在植入瓣膜与患者不匹配(PPM)现象。方法40例主动脉瓣环直径≤21mm的患者,其中20例置换人工生物瓣(生物瓣组),20例置换人工机械瓣(机械瓣组)。采用彩色多普勒超声心动图于术前和术后6个月～1年期间,检测两组患者的左心室射血分数(LVEF)、左心室短轴缩短率(LVFS)、左心室重量指数、瓣膜有效开口面积/体表面积的比值(EOAI)和主动脉瓣跨瓣压差的变化,并进行对比分析。结果术后6个月～1年,两组患者LVEF、LVFS和EOAI均较术前明显升高,左心室重量指数和主动脉瓣跨瓣压差均较术前明显减小或降低。所有患者术后EOAI为0.88～1.32cm2/m2,术后6个月～1年生物瓣组与机械瓣组比较:LVEF79%±8%vs.81%±10%;LVFS43%±9%vs.37%±8%;EOAI1.11±0.14vs.0.92±0.11;左心室重量指数89.10±16.70g/m2vs.95.30±15.10g/m2;主动脉瓣跨瓣压差18.80±12.60mmHgvs.22.30±12.00mmHg,差异无统计学意义(P>0.05)。结论小主动脉瓣环患者(直径≤21mm)置换人工生物瓣术后左心功能指标明显改善,无PPM现象。     

Hancock Ⅱ Ultra生物瓣行主动脉置换术后早期患者的血流动力学评价

目的 Hancock Ⅱ Ultra有支架生物瓣膜在主动脉瓣置换手术后早期血流动力学变化.方法 行单一主动脉瓣置换手术患者60例,随机分为两组,每组30例,分别使用Hancock Ⅱ Ultra生物瓣膜和Hancock Ⅱ生物瓣膜,术中测量实际瓣环直径,术后30天内及3个月分别行超声心动测量跨瓣血流峰速、跨瓣压差、有效瓣口面积指数及左室重量指数.结果 Hancock Ⅱ Ultra生物瓣组患者术后3个月左心室重量指数、跨瓣血流峰速及跨瓣压差均有显著改善.实测瓣环直径为23～ 25 mm和≥26 mm的患者,术后3个月跨瓣血流峰速、有效瓣环面积指数、左室流出道直径均无显著性差异;而实测瓣环直径≤23 mm的患者,血流峰速[(2.26±0.05) m/s对(2.57±0.06) m/s,t =2.07,P＜O.05]、平均压差[ (11.40±1.30) mm Hg(1 mm Hg =0.133 kPa)对(13.10 ±1.50) mmHg,t=2.09,P＜0.05]、有效瓣环面积指数[(0.79±0.13) cm2/m2对(0.71±0.02) cm2/m2,t=2.06,P＜0.05]、左心室重量指数[(119.10±11.10)g对(133.20±16.40)g,t=2.67,P＜0.05]、左心室流出道直径[(20.40±0.30) mm对(18.90±0.20) mm,t=2.23,P＜0.05],Hancock Ⅱ Ultra瓣组指标均优于Hancock Ⅱ组.结论 Hancock Ⅱ Ultra有支架生物瓣膜行主动脉置换,术后早期患者血流动力学结果满意,尤其适用于主动脉根部狭小患者,长期效果有待进一步随访.     

应用不同品牌机械瓣行主动脉瓣置换术患者的血流动力学变化

目的 探讨应用不同品牌19 mm机械瓣行单纯主动脉瓣置换术后早期血流动力学变化情况。 方法回顾性分析2007年1月至2012年1月北京安贞医院116例单纯主动脉瓣狭窄患者行主动脉瓣置换术后血流动力学变化,其中男61例、女55例,年龄（52±13） 岁。根据使用的瓣膜品牌将患者分为3组： SJ.Regent瓣膜组,38例（33%）,男20例、女18例,平均年龄（52±15） 岁; Carbomedics瓣膜组,40例（34%）,男21例、女19例,平均年龄（51±17） 岁。On-X瓣膜组,38例（33%）,男20例、女18例,平均年龄（55±16） 岁。比较患者术前和术后左心室收缩期末内径、左心室舒张期末内径、射血分数（EF）值、室间隔厚度、左心室壁厚度、主动脉瓣瓣上流速、跨瓣压差以及术后有效瓣口面积指数（EOAI）。 结果 三组患者术前及术后的左心室收缩期末内径、左心室舒张期末内径、EF值、室间隔厚度、左心室壁厚度差异均无统计学意义 （P＞0.05）。主动脉瓣瓣上流速和跨瓣压差术前、术后有差异有统计学意义。SJ.Regent瓣膜组和Carbomedics瓣膜组患者较On-X瓣膜组患者的术后主动脉瓣瓣上流速 ［（244.30±33.67） cm/s vs. （249.69±79.13） cm/s vs. （294.83±52.05） cm/s］和跨瓣压差［（27.77±3.33） mm Hg vs. （33.58±18.90） mm Hg vs. （38.56±13.21） mm Hg］明显偏小,其差异有统计学意义。 结论 运用19 mm机械瓣进行主动脉瓣置换术,SJ.Regent和Carbomedics瓣膜较On-X瓣膜有更好的血流动力学效果。     

主动脉瓣置换术650例临床分析

目的 总结主动脉瓣人工瓣膜置换术的临床经验.方法 主动脉瓣置换手术650例,年龄11～76岁,平均(43.2±12.6)岁.60岁以上52例.风湿性病变475例,先天性瓣叶畸形58例,退行性变49例,感染性心内膜炎(IE)47例,人工瓣膜感染性心内膜炎4例,外伤性2例.合并升主动脉瘤样扩张或主动脉夹层52例,冠心病36例,陈旧性脑血管意外14例,室间隔缺损10例,房间隔缺损2例,动脉导管未闭7例.心功能Ⅲ级385例,Ⅳ级119例.射血分数(EF)平均0.56±0.11,左室舒张末直径平均(LVED)(58.59±12.55)mm,左室舒张末容积(KVEDV)(191.58±89.88)ml,主动脉瓣跨瓣压差13.00～118.25 mm Hg(1mmHg=0.133kda).生物瓣占8.77%.主动脉瓣二次置换9例,同期行冠状动脉旁路术36例,主动脉大血管手术52例.体外循环110～208 mnin,升主动脉阻断54～129min.结果 人工瓣膜直径≤21 mm者术后跨瓣压差平均为30.00 mm Hg,直径>21 mm者术后跨瓣压差平均为23.00mmHg,差异有统计学意义.术后30d内死亡40例,1987-1996年死亡29例(9.21%);1997-2007年死亡11例(3.28%).平均随访58个月.结论 随着手术技术、心肌保护技术和围术期处理技术的提高,生物瓣的使用和对合并缺血性心脏病病人的再血管化,手术并发症和病死率明显下降.     

国产GK型双叶式人工心脏瓣膜的临床应用

目的观察和评价国产GK型双叶式人工心脏瓣膜(GK双叶瓣)植入人体后的早期临床疗效和近期随访结果。方法对61例心脏瓣膜病变患者行人工心脏瓣膜置换术,其中二尖瓣置换术(M VR)34例,主动脉瓣置换术(AVR)16例,二尖瓣和主动脉瓣双瓣膜置换术(M VR+AVR)11例。共植入GK双叶瓣72枚,其中二尖瓣45枚,主动脉瓣27枚;术后监测血液相容性和血流动力学指标,并定期随访和检查是否有与瓣膜相关的并发症发生。结果全组无手术死亡(术后30d内);随访61例,随访1年至2年6个月,远期因外伤死亡1例;其余60例患者术后心功能均从Ⅲ~Ⅳ级转为Ⅰ~Ⅱ级,血流动力学性能及生物相容性良好,生活质量改善。结论GK双叶瓣早期临床应用获得了满意的效果,其近期随访未发现与瓣膜相关的并发症,中、远期结果有待进一步随访观察。     

老年患者单纯主动脉瓣置换术术后人工瓣膜-患者的不匹配发生率及术后早期结果的研究

目的分析单纯主动脉瓣病变的老年患者主动脉瓣置换术后人工瓣膜-患者不匹配(PPM)现象及PPM对术后早期心功能及左心室重构的影响。方法回顾性分析2016年1~12月我院连续134例单纯主动脉瓣病变行主动脉瓣置换术65岁以上患者的临床资料,其中男73例、女61例,年龄65~79(69.7±3.6)岁。分析他们的临床及超声心动图数据,有效瓣口面积指数(EOAI)≤0.85 cm2/m2定义为PPM。对比主动脉瓣狭窄与主动脉瓣关闭不全患者术后PPM发生率,并对比机械瓣与生物瓣术后效果。结果 80例主动脉瓣狭窄患者中有26例发生PPM(发生率32.5%),54例主动脉瓣关闭不全患者中7例发生PPM(发生率13.0%),差异具有统计学意义(P0.05)。重度PPM 8例(发生率6.0%),1例患者术后早期死亡。结论单纯主动脉瓣反流行主动脉瓣置换术后PPM的发生率低于主动脉瓣狭窄的患者。     

成人小主动脉瓣环患者的心瓣膜置换术

目的总结成人小主动脉瓣环行心瓣膜置换术的临床经验，以提高手术效果。方法对26例成人小主动脉瓣环患者行人工机械瓣膜置换术，单纯主动脉瓣置换17例，二尖瓣、主动脉瓣双瓣膜置换9例。采用Manougnian法主动脉瓣环加宽7例，瓣膜侧倾缝合置换主动脉瓣膜6例，瓣环上主动脉瓣置换13例，在双瓣膜置换中均先置换主动脉瓣后再置换二尖瓣。结果26例患者中无手术死亡，术后随访时间6～48个月（12±3个月），心功能均明显改善（Ⅰ级10例、Ⅱ级16例），无远期死亡。术后主动脉瓣有效瓣口面积指数（EOAI）1．02～1．44cm^2／m^3（〉0．85cm^2／m^3），无瓣膜-患者不匹配现象（PPM）。结论主动脉瓣病变伴小主动脉瓣环的成人患者行心瓣膜置换，选择新型人工瓣膜行瓣环上主动脉瓣置换是理想的选择，瓣膜侧倾缝合是可选择的方法，二尖瓣、主动脉瓣双瓣膜置换时先置换主动脉瓣可降低手术操作难度，大部分患者无需行瓣环扩大术。     

主动脉瓣置换术后室间隔厚度对主动脉瓣跨瓣压差的影响

目的 探讨主动脉瓣置换术后室间隔厚度对主动脉瓣跨瓣压差的影响.方法 2005年1月至2010年12月,接受主动脉瓣置换术患者273例,全部为单纯主动脉瓣狭窄.根据手术时使用的主动脉瓣不同品牌,将患者分为3组:Regent组、On-x组、其他品牌组.定义术后跨瓣压差大小为:轻度(0～30 mm Hg,1 mm Hg=0.133 kPa)、中度(30 ～60 mm Hg)及重度(大于60 mm Hg).分别比较术前、术后测量的左心室收缩期末径、左心室舒张期末径、左心室射血分数(EF值)和室间隔厚度.结果 3组患者术前的左心室收缩期末径、左心室舒张期末径及EF值差异无统计学意义(P＞0.05).Regent组患者,术后跨瓣压差为重度的患者术前室间隔厚度明显多于轻、中度(P＜0.05).使用On-x组患者,术后跨瓣压差为重度与中度的患者术前室间隔厚度者明显多于轻度组(P＜0.05).其他品牌组患者,术后跨瓣压差为重度的患者术前室间隔厚度明显多于中、轻度组(P＜0.05).结论 行主动脉瓣置换术后,术前室间隔厚度大于13.6 mm的患者其主动脉瓣跨瓣压差较厚度小于13.6 mm的患者显著增高.室间隔厚度大于15.3 mm的患者,应同期行室间隔部分切除或替换无支架瓣膜以减少主动脉瓣替换后的跨瓣压差.     

2349例心脏瓣膜置换术早期死亡原因分析

目的 分析2349例心脏瓣膜置换术病人的死亡原因,以期进一步提高治疗水平.方法 1995年1月至2007年12月,2349例心脏瓣膜病病人接受人工心脏瓣膜置换手术.其中二尖瓣置换术(MVR)1333例,主动脉瓣置换术(AVR)271例,二尖瓣、主动脉瓣同期置换术(DVR)736例,三尖瓣置换术(TVR)9例.结果 早期病死率1995年至1999年6.81%,2000年至2004年3.22%,2005年至2007年2.82%.全组总早期病死率3.40%.结论 心脏瓣膜置换术早期死亡的原因主要是低心排血量综合征、肾功能衰竭、心律失常、肺部感染、脑血管意外、左室破裂和多器官系统功能衰竭等.     

Impact of valve prosthesis-patient mismatch on intermediate-term outcome and regression of left ventricular mass following aortic valve replacement with mechanical prosthesis

BACKGROUND: The impact of aortic valve replacement (AVR) with prosthesis-patient mismatch (PPM) on intermediate-term outcome and left ventricular mass (LVM) regression in patients with aortic stenosis (AS) was investigated. METHODS: One hundred fifty patients with AS (87 pure stenosis and 63 combined stenosis and regurgitation) were classified into a PPM group (n = 34, indexed effective orifice area (EOAI) >0.65 cm(2)/m(2) and < or =0.85 cm(2)/m(2); moderate PPM) and a non-PPM group (n = 116, EOAI > 0.85). Mean age, mean and peak aortic pressure gradient (PG) were not different between the groups (PPM, 99.7 +/- 37.2 and 54.9 +/- 23.2 mmHg; non-PPM, 95.9 +/- 29.2 and 54.4 +/- 16.0 mmHg). The absolute and relative regression in indexed left ventricular mass (LVMI) was estimated by preoperative and postoperative echocardiography (n = 98). RESULTS: Twelve patients died (valve-related death in 7) during 5 years of follow-up. Comparing the PPM and non-PPM groups, overall survival (78.7% vs. 87.8%) and survival free from valve-related death (96.8% vs. 92.1%) were not significantly different. New York Heart Association (NYHA) functional class improved in all patients and there were no patients in class III or IV. The postoperative mean PG was 14.6 +/- 6.1 mmHg in the PPM group and 9.4 +/- 3.8 mmHg in the non-PPM group (p = 0.0005), with an inverse correlation (r = -0.48, p < 0.0001) between EOAI and the postoperative mean PG. However, there was no significant difference in the absolute and relative LVMI regression between the two groups. Multiple linear regression analysis was performed and higher preoperative LVMI and mean aortic PG were independent predictors of greater LVMI regression after AVR. CONCLUSIONS: Moderate PPM does not appear to alter LVMI regression, NYHA class, or intermediate-term outcome in AS patients undergoing AVR with mechanical prostheses. In multivariate analysis, preoperative LVMI and mean aortic PG were important independent predictors of LVMI regression.     

Is the threshold for postoperative prosthesis-patient mismatch the same for all prostheses?

Purpose

The effective orifice area index (EOAI) is used to define the prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR). However, few studies have so far evaluated whether the cutoff value for PPM varies across prostheses. This study assessed the hemodynamics in patients given a mechanical valve and then re-evaluated the validity of the commonly accepted threshold.

Methods

The subjects included 329 patients that underwent AVR with a St. Jude Medical Regent valve. The transvalvular pressure gradient and EOAI were determined echocardiographically, and the commonly accepted threshold was analyzed in relation to survival.

Results

The mechanical valves very often yielded a postoperative transvalvular pressure gradient >10 mmHg, and thus, clinically significant residual pressure, regardless of the EOAI. The slope of the curve describing the relationship between the transvalvular pressure gradient and EOAI was gentler than that reported for bioprosthetic valves, for which the pressure gradient rises sharply at EOAI <0.85 cm²/m². The commonly defined PPM did not affect the long-term survival or regression of the left ventricular mass index.

Conclusions

The relationship between the transvalvular pressure gradient and the EOAI in patients given a mechanical prosthesis differed from the reference standard. These data suggest the need to reconsider the appropriate cutoff value for PPM in relation to different prostheses.     

Effect of prosthesis-patient mismatch on survival after aortic valve replacement using mechanical prostheses in patients with aortic stenosis

Background  This study assessed the effects of prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR) using mechanical prostheses in patients with aortic stenosis. Methods  A total of 124 patients with aortic stenosis who underwent AVR with mechanical prostheses were followed (mean 9.1 ± 4.9 years). The patients were divided into two groups based on the effective orifice area index (EOAI): Group A did not have significant PPM, defined as an EOAI ≥ 0.85 cm²/m²; and the PPM group had significant PPM, defined as an EOAI < 0.85 cm²/m². Results  In all, 25 patients (20.2%) had PPM. The operative mortality was 6.1% in group A and 12.0% in the PPM group; the difference between the groups was not significant. Moreover, the difference in overall survival rates between group A and the PPM group was not statistically significant (15-year postoperative survival: group A 78.5% vs. PPM group 81.3%). Although there were four late deaths in the PPM group, only one was valve-related. PPM had no effect on late survival. Postoperatively, cardiac function and physical activity levels improved in both groups; the extent of improvement was not dependent on the presence or severity of PPM. Conclusion  Although PPM may affect operative mortality, the effect of PPM appears to decrease over time. PPM had no effect on late survival.     

Patient-prosthesis mismatch after aortic valve replacement; tolerable lower limit of indexed effective orifice area

This study was aimed at determining the tolerable lower limit of the indexed effective orifice area (EOAI) to prevent patient-prosthesis mismatch (PPM). Echocardiography was performed in 87 consecutive patients who underwent aortic valve replacement (AVR). EOAI was estimated for each type and size of prosthesis and used to define PPM as moderate if >0.65 cm2/ m2 and < or = 0.85 cm2/m2, and severe if < or = 0.65 cm/m2. Aortic valve pressure gradients, left ventricular dimensions, and outcome (in-hospital and 1-year) were analyzed in the presence or absence of abnormal gradients (> or = 40 mmHg) to assess the influence of a small valve (19 mm or less labeled size). Severe PPM was found in 23% of all patients, and 50% of the severe PPM patients had an abnormal gradient. There was 1 death and 1 brain damage from ventricular fibrillation because of severe PPM in the abnormal gradient group with a small valve. In PPM patients with a small valve, EOAI (0.61 +/- 0.04 vs 0.69 +/- 0.07) and preoperative interventricular septal thickness (IVST : 16.4 +/- 2.6 mm vs 13.5 +/- 1.5 mm) were significantly different between abnormal and normal gradient groups. An EOAI > or = 0.69 appeared to be tolerable in patients with a lower level of hypertrophy (IVST < 16 mm).     

Aortic valve replacement with a small valve prosthesis: a review of clinical and echocardiographic studies for impact of prosthesis-patient mismatch

Aortic valve replacement (AVR) has become standard therapy for treating diseases of the aortic valve. However, the selection of a prosthetic valve is considered to be an important factor determining postoperative recovery of cardiac function and quality of life, because the use of small valve prostheses may cause residual obstruction to left ventricular outflow. The situation in which "the effective prosthetic valve area, after insertion into the patient, is less than that of a normal human valve," has been described as "prosthesis-patient mismatch (PPM)." The most commonly used measure of PPM is the valve effective orifice area indexed to body surface area (EOAI), and PPM is generally defined as EOAI < or =0.85cm(2)/m(2). In this paper, we review clinical and echocardiographic studies of small valve prostheses in the aortic position to investigate the clinical impacts of PPM on short- and long-term outcomes after AVR. Some studies have shown decreased symptom resolution, poor regression of left ventricular mass, or decreased survival with an EOAI < or =0.85cm(2)/m(2), while others have observed no adverse effects of PPM on short- and long-term results of AVR. Therefore, even in Western countries, in studies involving large numbers of patients, conclusions drawn concerning the impact of PPM differ greatly among reports. In conclusion, it is desirable to examine in detail, in many patients, whether the use of prosthetic valves with EOAI < or =0.85cm(2)/m(2) is also a risk factor for poor prognosis in Japanese patients, whose body size is in general smaller than that of Western patients.     

Avoidance of patient-prosthesis mismatch

To minimize the incidence of patient-prosthesis mismatch (PPM), we have routinely adopted aortic root enlargement to avoid PPM for patients with small aortic annulus. The aim of this study was to review our strategy of avoiding PPM. The Carpentier-Edwards Perimount (CEP) valves were implanted in 53 patients who were mostly aged over 65 and the St. Jude Medical (SJM) mechanical valves were used in 128 patients aged under 65. A standard 21-mm SJM valve was used in only 3 patients and no 19-mm valves were employed. However, 19-mm CEP valves were used in 12 patients with a small body surface area (1.43 +/- 0.14 m2). Of these, 26 patients (14.4%) who had a small aortic annulus and 24 patients aged under 65 underwent aortic root enlargement. No patient receiving an SJM valve had an projected indexed effective orifice area (EOAI) < or = 0.85 cm2/m2 because of performing aortic valve replacement (AVR) with annular enlargement and only 2 (3.8%) out of 53 patients receiving CEP valves developed PPM. Consequently, the prevalence of PPM was 1.1% in this series. The prevalence of PPM was low in patients over 65 years old with a relatively small body size who received bioprosthetic valves. A pericardial bioprosthesis was considered to be an appropriate valve in older population with regard to avoiding PPM. In patients under 65 years old with a small annulus, the first choice for avoiding PPM is aortic annular enlargement, which may be avoided by high performance mechanical valves with larger EOA.     

二尖瓣位人工瓣膜患者不匹配的初步研究

目的 分析二尖瓣置换术后人工瓣膜患者不匹配(PPM)的发生原因.方法 连续入组2009年1月至6月间接受择期二尖瓣置换术的患者100例,男性37例,女性63例;年龄32～76岁,平均(52±9)岁.术前主要病变为二尖瓣狭窄60例,二尖瓣关闭不全14例,二尖瓣狭窄合并关闭不全26例;合并三尖瓣关闭不全63例.多普勒超声心动图测量人工二尖瓣膜有效瓣口面积,并计算有效瓣口面积指数(EOAI).以人工二尖瓣EOAI＜1.2 cm2/m2作为PPM诊断标准,将患者分为不匹配组和匹配组,对比分析两组患者临床资料.结果 52例患者二尖瓣置换术后发生PPM(52.0%).中度PPM 51例(51.0%),重度PPM 1例(1.0%).不匹配组中男性患者比例高于匹配组(55.8%比16.6%,P＜0.01),体表面积大于匹配组[(1.76±0.17)m2比(1.59±0.13)m2,P＜0.01].两组患者术前病理改变及术中应用人工瓣膜的种类、型号及手术方式无明显差异.术后两组患者心脏结构和功能及三尖瓣关闭不全的发生率无明显差异.结论 二尖瓣位PPM好发于男性、体表面积较大的患者.术中考虑性别、体表面积等因素,选择稍大型号的人工瓣膜,有利于减少术后PPM的发生.

Abstract：

Objective To analysis the causes of valve prosthesis-patient mismatch (PPM) after mitral valve replacement in Chinese patients. Methods Consecutive 100 patients for elective mitral valve replacement from January 2009 to June 2009 were enrolled and followed for this study. There were 37 males and 63 females. The mean age at operation was (52 ± 9 ) years ( ranging 32 to 76 years). The predominant mitral valve lesion was stenosis in 60 patients, regurgitation in 14 patients and mixed in 26 patients. Among them, 63 patients were combined tricuspid valve regurgitation.Mitral valve effective orifice area was measured by Doppler echocardiography in 100 patients who received mitral valve replacement and indexed for body surface area (EOAI). PPM was defined as not clinically significant if the EOAI was above 1.2 cm2/m2, as moderate ifit was ＞0.9 and ≤1.2 cm2/m2, and as severe ifit was ≤ 0.9 cm2/m2. By using the criteria, all 100 patients were classified to two groups: PPM group and no PPM group. The clinical characteristic of the patients between the two groups was compared to determine the causes of PPM and the predictors of outcomes after mitral valve replacement, such as the gender, age, valve prosthesis type, size,body surface area, and mitral valve lesion, et al. Results Of the 100 patients after MVR, 52 (52. 0% )had significant PPM, 51 (51.0%) had moderate PPM, and 1 (1.0%) had severe PPM. In comparison to patients in no PPM group, patients in PPM group had a significantly larger body surface area [( 1.76 ±0. 17) m2 vs. (1.59 ±0. 13) m2, P＜0.01] and higher prevalence of male gender (55.8% vs. 16.6%,P＜0. 01). The other preoperative and operative data were similar in both groups, such as the valve prosthesis type, size, and mitral valve lesion, et al. There were no significant differences in postoperative Doppler-echocardiographic data of cardiac structure and heart function between the two groups (P ＞ 0. 05 ).Conclusions The higher incidence of PPM in mitral valve position was in male or large body surface area patients. At the time of operation, surgeons should consider the related factors, such as the patient's gender and body surface area, et al. A larger prosthesis size might be implanted to avoid PPM in mitral valve position.     

液氮保存同种带支架人工瓣膜流体力学测试

目的：利用脉动流模拟实验装置测试液氮保存同种带支架瓣膜流体力学性能，同时与国产perfect牛心包人工瓣膜对比研究。方法：采集同种瓣膜，缝制成21^#、23^#、25^#同种带支架主动脉和同种带支架肺动脉人工瓣膜，经液氮保存，使用国产脉动流实验装置测试瓣膜流体力学性能，采用ISO／FDA浮估标准，分别测量各流量下的跨瓣压差、有效瓣口面积(EOA)和回流比。并与相应型号国产perfect牛心包人工瓣膜对比研究。结果：21^#、23^#、25^#同种带支架主动脉和肺动脉瓣膜的跨瓣压差和回流百分比差异无显著性，但较perfect瓣大。同种带支架主、肺动脉瓣膜的EOA差异无显著性，但较perfect牛心包生物瓣膜的略小些。同种带支架瓣膜实际开口面积(AOA)小于perfect牛心包瓣，但有效瓣口面积，实际开口面积比值无差别。结论：同种带支架主动脉和肺动脉人工瓣膜流体力学性能满意，同种带支架主动脉瓣膜与同种带支架肺动脉瓣膜流体力学性能无差别。     

Aortic valve replacement in elderly patients with small aortic annulus; is the indexed effective orifice area important?

We sought to determine whether the small indexed effective orifice area (EOAI) increased mortality and morbidity after aortic valve replacement (AVR) in patients over 75 years of age. From May 1999 to July 2005, 77 patients underwent isolated AVR for aortic stenosis. They were divided into 3 groups (S-EOAI : EOAI < or = 0.7 cm2/m2, M-EOAI : 0.7 cm2/m2 相似文献   

Patient-prosthesis mismatch after small-size stentless aortic valve replacement

OBJECTIVE: The aim of this study was to determine the occurrence of patient-prosthesis mismatch (P-PM) after aortic valve replacement (AVR) with a small-size Cryolife O'Brien (CLOB) bioprosthesis and to evaluate its clinical and hemodynamic implications. METHODs: Sixty-two patients (mean age 70.9 +/- 5.2 years, 77.8% females), receiving a labeled 21-23 mm CLOB between 1993 and 2000, were retrospectively studied. Effective orifice area (EOA) was calculated by the continuity equation and then indexed to the patient's body surface area (BSA) to obtain the indexed EOA (EOAI). Based on previous observations a mismatch was defined as EOAI or= 0.8 cm/m2 showed an earlier concentric remodeling up to 1 year; no difference was demonstrated at later studies between groups. Survival and clinical status results were not affected by an EOAI 相似文献