Ischemic mitral valve regurgitation grade II-III: correction in patients with impaired left ventricular function undergoing simultaneous coronary revascularization.

BACKGROUND AND AIM OF THE STUDY: Mitral valve regurgitation (MVR), occurring as a result of myocardial ischemia and global left ventricular (LV) dysfunction, is predictive of poor outcome. The study aim was to assess the feasibility of mitral valve surgery concomitant with coronary artery bypass grafting (CABG) in patients with ischemic MVR grade II-III and impaired LV function. METHODS: Between January 1996 and July 2000, 99 patients with grade II and III ischemic MVR and LV ejection fraction (LVEF) 17-30% underwent either combined mitral valve surgery and CABG (group I, n = 49) or isolated CABG (group II, n = 50). LVEF (%), LV end-diastolic diameter (LVEDD; mm), LV end-diastolic pressure (LVEDP; mmHg), LV end-systolic diameter (LVESD; mm) respectively were 27.5+/-5, 67.7+/-7, 27.7+/-4 and 51.4+/-7 in group I versus 27.8+/-4, 67.5+/-6, 27.5+/-5 and 51.2+/-6 in group II. In group I, mitral valve repair was performed in 43 patients (88%) and replacement in six (12%). RESULTS: Preoperative data analysis showed no difference between groups. Five patients (10%) died in group I, compared with six (12%) in group II (p = NS). Within six months of surgery, LV function and geometry improved significantly in group I versus group II (LVEF, p <0.001; LVEDD, p = 0.002; LVESD, p = 0.003, LVEDP, p <0.001); only mild improvements were seen in group II. The regurgitation fraction decreased significantly in group I patients after surgery (p <0.001). Cardiac index increased significantly in groups I and II (p <0.001 and p = 0.03, respectively). In group I at follow up, four of six patients undergoing mitral valve replacement died, compared with five of 43 patients (11.5%) undergoing mitral valve repair (p = 0.007). At three years, the overall survival in group II was significantly lower than in group I (p <0.009). CONCLUSION: Both MV repair and replacement preserving subvalvular apparatus in patients with impaired LV function offered acceptable outcome in terms of morbidity and survival. Surgical correction of grade II-III MVR in patients with impaired LV function should be taken into consideration as it provides better survival and improves LV function.     

Mitral valve surgery simultaneous to coronary revascularization in patients with end-stage ischemic cardiomyopathy

Mitral valve regurgitation (MVR), occurring as a result of myocardial ischemia and global left ventricular (LV) dysfunction, predicts a poor outcome in terms of survival and morbidity. Between 1995 and 2003, 180 consecutive patients with impaired LV function and chronic ischemic MVR underwent cardiac surgery. Fifty-four patients (group I), MVR (grade III–IV) underwent simultaneous MV surgery and coronary artery bypass grafting (CABG); 40 patients (group II), MVR (grade II–III), and 86 patients (group III), MVR (grade I–II), underwent CABG alone. In group I, MV repair was performed in 36 patients (group IA) and MV replacement in 18 (group IB). The incidence of hospital death was similar between groups. The actuarial event-free survival was significantly lower in group than in groups II and III (P = 0.0045) and I (P = 0.038). The overall actuarial survival was significantly higher in group IA than in group IB (P = 0.027). Postoperatively, the LV ejection fraction (P < 0.001), LV end-diastolic diameter (P < 0.001), LV end-systolic diameter (P < 0.01), and cardiac index (P < 0.001) improved significantly in group I. The regurgitation fraction decreased significantly in Groups I and III after surgery (P < 0.001 and P = 0.003, respectively). Both MV repair and replacement that preserves subvalvular apparatus in patients with end-stage ischemic myocardiopathy offer an acceptable outcome. Mitral valve repair simultaneous to CABG improves significantly the LV function and its geometry. In patients with mild to moderate mitral regurgitation, CABG alone may be performed with good overall survival, but with lower event-free survival than those undergoing concomitant mitral valve repair.     

部分或全部保留瓣下结构的二尖瓣置换术对巨大左室几何学的影响

目的 动态观察二尖瓣置换术(Mitral valve replacement,MVR)后巨大左心室的几何学变化，对比3种不同术式对左心室形态学逆转的影响。方法 回顾性分析1992年1月至2002年1月间48例巨大左心室病人施行二尖瓣置换术后的超声心动图随访资料。结果 保留二尖瓣装置对巨大左心室形态的逆转有效，其中保留全部瓣下结构术后左窒缩小最显，部分保留其次，无保留术后早期缩小晚期再扩大。结论 对于二尖瓣关闭不全为主合并巨大左室。应尽量采用保留瓣下结构的术式，有利于术后晚期左心室形态的逆转。     

Superiority of mitral valve replacement with preservation of subvalvular structure to conventional replacement in severe rheumatic mitral valve disease: a modified technique and results of one-year follow up

BACKGROUND AND AIM OF THE STUDY: Mitral valve replacement with preservation of the subvalvular apparatus (MRVP) has been proven superior to conventional mitral valve replacement (MVR). We devised a simple modified MVRP method in this prospective, randomized study to investigate the clinical effects and one-year follow up echocardiographic results of MVRP compared with MVR in patients with severe rheumatic mitral insufficiency (MI). METHODS: Sixty-eight patients with severe rheumatic MI with or without stenosis were randomized to MVRP (n = 35) and MVR (n = 33) groups. In MVRP patients, the preserved tissue was pulled back posteriorly to the posterior wall of the left ventricle, then plicated and reaffixed to one-fourth of the annular circumference in the posterior annulus, in order to prevent left ventricular outflow tract (LVOT) obstruction. Clinical data including cumulative ventricular arrhythmias and use of inotropes were collected. Echocardiography examination was performed before surgery, and at five days, three months and one year thereafter. RESULTS: There were no preoperative differences patient data. The cross-clamp time was 2.2 min longer in MVRP patients. The one-month mortality rate after surgery was lower in MVRP patients (2.9% versus 15.2%, p = 0.074). Mechanical ventilation and ICU times were shorter in the MVRP group (17.6 versus 24.8 and 52.5 versus 70.6 h, p = 0.001 and 0.1, respectively). There were fewer ventricular arrhythmias and less need for inotropic support in this group. One year follow up echocardiography data showed better preserved left ventricular ejection fraction (LVEF) and better recovery of heart size after MRVP. There was no indication that preserved valvular tissue interfered with mechanical valve function, or caused LVOT obstruction. CONCLUSION: This modified MVRP technique is simple, effective and without risk of LVOT obstruction. In severe rheumatic MI patients the outcome of MVRP is superior to that of conventional MVR in term's of mortality, postoperative care needs, left ventricular function and heart dimensions.     

Papillary Muscle Repositioning as a Subvalvular Apparatus Preservation Technique in Mitral Stenosis Patients with Normal Left Ventricular Systolic Function

Subvalvular apparatus preservation is an important concept in mitral valve replacement (MVR) surgery that is performed to remedy mitral regurgitation. In this study, we sought to determine the effects of papillary muscle repositioning (PMR) on clinical outcomes and echocardiographic left ventricular function in rheumatic mitral stenosis patients who had normal left ventricular systolic function.We prospectively assigned 115 patients who were scheduled for MVR surgery with mechanical prosthesis to either PMR or MVR-only groups. Functional class and echocardiographic variables were evaluated at baseline and at early and late postoperative follow-up examinations. All values were compared between the 2 groups.The PMR group consisted of 48 patients and the MVR-only group of 67 patients. The 2 groups’ baseline characteristics and surgery-related factors (including perioperative mortality) were similar. During the 18-month follow-up, all echocardiographic variables showed a consistent improvement in the PMR group; the mean left ventricular ejection fraction deteriorated significantly in the MVR-only group. Comparison during follow-up of the magnitude of longitudinal changes revealed that decreases in left ventricular end-diastolic and end-systolic diameters and in left ventricular sphericity indices, and increases in left ventricular ejection fractions, were significantly higher in the PMR group than in the MVR-only group.This study suggests that, in patients with rheumatic mitral stenosis and preserved left ventricular systolic function, the addition of papillary muscle repositioning to valve replacement with a mechanical prosthesis improves left ventricular dimensions, ejection fraction, and sphericity index at the 18-month follow-up with no substantial undesirable effect on the surgery-related factors.Key words: Cardiac output, chordae tendineae/surgery, left ventricular function, mitral valve replacement, mitral valve stenosis/surgery, papillary muscles/surgery, subvalvular apparatus, tissue preservation/methods, ventricular function, leftMitral valve replacement (MVR) with a mechanical or a bioprosthetic valve is one of the most performed cardiac surgical procedures. Although in recent years valve repair has usually been preferred to replacement, MVR is inevitable when repair is not feasible. After MVR, low cardiac output syndrome develops in some patients, because the subvalvular apparatus has not been spared.¹ Because the subvalvular apparatus provides continuity between the mitral annulus and the left ventricular (LV) wall through the leaflets, chordae tendineae, and papillary muscles, it plays an important role in LV function.² Several studies^3–3 have shown that protection of the subvalvular apparatus during MVR can decrease the risk of low cardiac output syndrome, reduce the operative mortality rate, and improve postoperative LV systolic function. Various approaches to subvalvular apparatus preservation have been developed.^6–9Papillary muscle repositioning (PMR) is a subvalvular apparatus-sparing method that can be applied to both the anterior and posterior mitral annulus. In patients with LV dysfunction and mitral regurgitation, several studies^10,11 have shown favorable effects of papillary muscle repositioning on LV remodeling; however, the effect of subvalvular-apparatus-sparing surgery (including PMR) on LV mechanics has not yet been fully elucidated in patients who have isolated mitral stenosis and preserved LV function.^12,13In this study, we examined the effectiveness of PMR on LV function and clinical outcome in patients with isolated mitral stenosis and preserved LV systolic function who undergo MVR.     

Mitral valve repair versus replacement for isolated non-ischemic mitral regurgitation in patients with preoperative left ventricular dysfunction. A long-term follow-up echocardiography study.

The aim of this study was to evaluate LV function, by means of echocardiography, after mitral valve repair (MVr) or mitral valve replacement (MVR) in patients (pts) with chronic degenerative mitral regurgitation (MR) and depressed LV systolic function during a 6-years follow-up (FU) period. PATIENTS AND METHODS: Forty-five pts with moderately severe or severe MR and preoperative EF相似文献   

保留瓣下结构的二尖瓣替换术后早期效果观察

目的：二尖瓣关闭不全患者行常规二尖瓣替换术后常有左心室功能恶化，有作者推测术中二尖瓣结构的破坏是导致术后左心室功能不全的主要原因之一。本文旨在探讨保留瓣下结构的影响。方法：总结了保留瓣下结构的二尖瓣替换术２６例，其中部分保留２２例为二尖瓣狭窄，完全保留４例为二尖瓣关闭不全。结果：与同期完全切除的２６例（均为二尖瓣狭窄）比较，保留瓣下结构者术后低心输出量综合征发生率较低，左心房缩小较明显，未发生左心室破裂。其余５项指标两组间无差异。结论：二尖瓣关闭不全者应完全保留瓣下结构，其中将人工瓣置入二尖瓣口内更为简便安全。部分二尖瓣狭窄者可保留后瓣及瓣下结构，而瓣叶和瓣下结构病变严重者则应完全切除。     

The renin-angiotensin system genetic polymorphisms and rheumatic mitral valve disease

BACKGROUND AND AIM OF THE STUDY: Angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism, angiotensinogen (AGT) gene polymorphism and angiotensin II type 1 receptor (AT1R) polymorphism in relation to rheumatic mitral valve disease were examined in a case-control study to investigate possible relationships between these gene polymorphisms and rheumatic mitral valve disease in patients undergoing mitral valve replacement (MVR). METHODS: A total of 50 patients with rheumatic mitral valve disease and undergoing MVR was compared with 50 normal, and age- and sex-matched control subjects. ACE I/D, AGT gene M235T and AT1R-adenine/cytosine 1166 (A1166C) genotype polymorphisms were identified by polymerase chain reaction (PCR) -based restriction analysis. RESULTS: ACE I/D polymorphism differed significantly between the groups. The control group mostly represented the heterozygote ID allele (74%), while the MVR group showed frequencies of 60% for the homozygote DD and II alleles. MM homozygote frequency was significantly greater in controls, but TT homozygote frequency was significantly greater in the MVR group. AT1R-A1166C genotype polymorphism also differed significantly between groups; the MVR group had 73.7% of the AC heterozygote allele, while controls had 64.4% of the AA and 66.7% of the CC homozygote alleles. CONCLUSION: These results provided evidence of an association between ACE I/D polymorphism, M235T polymorphism and AT1R-A1166C genotype polymorphism and rheumatic mitral valve disease.     

Early beneficial effect of preservation of papillo-annular continuity in mitral valve replacement on left ventricular function

BACKGROUND AND AIM OF THE STUDY: Impairment of left ventricular (LV) function after mitral valve replacement (MVR) has been the most important factor to determine morbidity and mortality. With this in mind, LV performance in the postoperative period was assessed with and without preservation of papillo-annular continuity in MVR. METHODS: Between March 1994 and August 1998, a total of 383 valve prostheses (202 MVR, 65 AVR, 58 MVR+AVR) were implanted in 325 patients, 177 of whom underwent MVR with Starr Edwards ball cage prostheses (the study group). Of these 177 patients, 105 had MVR with preservation of the posterior mitral leaflet (group I), and 72 had conventional MVR (group II). Predominant lesions were mitral stenosis in 81, mitral regurgitation in 42, and mixed mitral lesion (MS/MR) in 54. Concomitant tricuspid valve annuloplasty was performed in 13, and atrial septal defect repair in five. Sixteen patients underwent MVR for mitral restenosis. In-vivo performance of the prostheses and LV function was evaluated by M-mode and Doppler echocardiography. RESULTS: At 3-6 months clinical improvement was seen in NYHA class, with reduction in cardiothoracic ratio among patients with preserved papillo-annular continuity, irrespective of lesion type. Significant reductions (p <0.05) were seen in left atrial dimensions (54.10 +/- 8.79 preop. versus 44.64 +/- 8.54 postop.; p <0.05), left ventricular end-diastolic dimensions (LVEDD) (50.84 +/- 10.42 preop. versus 41.21 +/- 7.16 postop.; p <0.05) and end-systolic dimensions (LVESD) (34.76 +/- 7.94 preop. versus 28.81 +/- 5.79 postop.; p <0.05) in patients who had their posterior mitral leaflet preserved with significant improvement in ejection fraction (60.31 +/- 8.22 versus 64.47 +/- 7.93; p <0.05). Further analysis of data in group I patients showed significant reductions in left atrial dimensions, LVESD and peak gradient, along with improved ejection fraction compared with conventional (group II) patients. CONCLUSION: Deterioration in LV function in patients undergoing conventional MVR indicates chordal resection as a putative mechanism. This study supports the concept that maintenance of continuity between the mitral annulus and papillary muscles has a beneficial effect on postoperative LV function, and is particularly important in patients with mitral stenosis with depressed preoperative LV systolic function.     

人工腱索植入术对二尖瓣置换术后患者左心功能的影响

目的:探讨人工腱索植入术对风湿性心脏病患者二尖瓣置换术后左心功能的影响。方法:回顾性分析50例因患风湿性心脏病而需要进行二尖瓣置换手术(mitral valve replacement,MVR)患者的临床资料,根据术中对二尖瓣不同处理方式分为两组:A组(n=26),切除全部瓣膜及瓣下结构组;B组(n=24),为需切除全部瓣膜及瓣下结构的患者实行人工腱索植入术重建瓣下结构。分别于术后3个月对患者进行彩色多普勒超声心动图检查,测量患者左心功能,比较两组间各项指标的差别。结果:术后3个月B组患者左心室射血分数(LVEF)改变优于A组(P0.05)。结论:二尖瓣置换术中,人工腱索植入重建瓣下结构的技术安全有效,对患者术后短期左心功能的恢复有良好改善,长期效果仍需进一步观察。     

Mitral valve replacement with complete mitral leaflet retention: operative techniques

BACKGROUND AND AIMS OF THE STUDY: This report describes surgical indication and operative technique of complete preservation of the mitral valvular and subvalvular apparatus during mitral valve replacement. METHODS: Twenty patients, 12 with rheumatic lesions and eight with congenital lesions, were operated between 1991 and 1996. The left atrium was opened using a trans-septal approach through the right atrium in 17 patients, and at the intra-atrial groove in three. The valve was sized without excising any mitral valvular or subvalvular tissue. Teflon pledget-reinforced horizontal mattress valve sutures were passed from the left atrium, through the mitral annulus, around the free edge of mitral leaflet, and up through the prosthetic sewing ring. The prosthetic valve was seated and the sutures tied, reefing the native leaflets and compressing them between the sewing ring and native annulus. Thus, chordal tension on the ventricle was evenly maintained. RESULTS: There was no operative or late death. Postoperative results were excellent. Echocardiography showed that none of the patients had any observable anterior leaflet and redundant subvalvular tissue in the left ventricular outflow tract (LVOT); thus, neither LVOT obstruction nor interference with prosthetic valve function occurred. CONCLUSIONS: Based on these findings, it is suggested that when mitral valve replacement is required in patients with mitral insufficiency (MI) or MI with mild stenosis, the mitral valvular and subvalvular tissue should be completely preserved.     

瓣下结构保留方式对二尖瓣置换术后瓣膜下游湍流剪应力的影响

目的观察瓣下结构保留方式对二尖瓣置换术后猪瓣膜下游湍流剪应力(TSS)的影响。方法滇南小耳猪27只,在全麻气管插管体外循环下行二尖瓣置换术。随机分为A、B、C组,各9只,分别采用单叶机械瓣膜、双叶机械瓣膜和生物瓣膜行二尖瓣置换。每组又分为3个小组,各3只,A1、B1、C1组未保留瓣下结构,A2、B2、C2组保留后瓣瓣下结构,A3、B3、C3组保留全瓣瓣下结构。采用彩色多普勒技术检测各组人工心瓣下游湍流剪应力。结果猪单叶瓣膜置换术后二尖瓣下游两核心区位点TSS组间比较P均>0.05,边界位点TSS组间比较P均<0.05,保留后瓣瓣下结构者高于不保留瓣下结构者,低于全保留瓣下结构者(P均<0.05)。猪双叶瓣膜置换术后、生物瓣膜置换术后二尖瓣下游两核心区位点TSS组间比较P均>0.05,边界位点TSS不保留瓣下结构者和保留后瓣瓣下结构者相比P>0.05,全保留瓣下结构者高于不保留瓣下结构和保留后瓣瓣下结构者(P均<0.05)。结论采用单叶机械瓣行二尖瓣置换术保留后瓣和保留全瓣均可引起跨瓣血流湍流强度增大,且保留全瓣高于保留后瓣者;采用双叶瓣膜和生物瓣膜者,保留后瓣瓣下结构不会导致跨瓣血流湍流强度增大,但保留全瓣可引起跨瓣血流湍流强度增大。     

Results of the Ross operation in rheumatic versus non-rheumatic aortic valve disease

BACKGROUND AND AIM OF THE STUDY: A total of 213 patients underwent the Ross operation at our institution between January 1990 and January 1999. Outcome was assessed in rheumatic (RH) patients and compared with that in patients with other etiology (non-RH). METHODS: After exclusion of 69 patients with a follow up of <18 months, the study group comprised 144 patients (119 RH, 25 non-RH). Patients were studied clinically and by echo-Doppler cardiography preoperatively, within 2 months and 6-8 months after surgery, and yearly afterwards. Preoperative assessment included age, gender, body surface area (BSA), type of aortic valve lesion and additional valve disease, left and right ventricular outflow tract (LVOT, RVOT) dimensions, and left ventricular (LV) size, function and mass. Postoperatively, patients were studied for presence and severity of autograft regurgitation, mitral regurgitation, LV size, function and mass, and incidence and timing of reoperation. RESULTS: On average, RH patients were older and had higher BSA, more aortic regurgitation than stenosis, more additional mitral valve disease (mostly regurgitation), larger LV size and poorer LV function. Mitral valve repair was performed in 24% of RH patients versus 0% of non-RH patients. Postoperatively, differences in LV size, function and mass remained present, but diminished during follow up. The autograft reoperation incidence was 22% (26/119) in RH patients versus 8% (2/25) in non-RH patients (p = NS). Preoperative predictors for reoperation in the RH group were severe concomitant mitral regurgitation (MR), followed by male gender and large indexed LVOT (all p<0.001 by discriminant analysis). CONCLUSION: Marked differences were present in patient characteristics between rheumatic and nonrheumatic patients who underwent the Ross operation. Rheumatic patients had a higher incidence of autograft reoperation. Severe concomitant MR was the most important predictor for reoperation in rheumatic patients.     

核素心室造影对保留二尖瓣的二尖瓣替换术临床疗效的初步评价

目的：评价保留二尖瓣的二尖瓣替换术临床效果。方法：采用平衡法核素心室造影，对１３例二尖瓣病变患者术前术后进行心功能测定。测定参数：左心室射血分数、局部射血分数、右心室射血分数及舒张末期与收缩末期的径线缩短率。结果：保留二尖瓣组（ｎ＝７）左心室射血分数术前术后无明显变化，左心室侧壁、下壁心尖部局部射血分数明显改善。不保留二尖瓣组（ｎ＝６），左心室射血分数于术前术后无明显变化，仅左心室侧壁局部射血分数改善。结论：保留二尖瓣的二尖瓣替换术对术后心功能的改善具有良好的效果，核素心室造影对评价手术疗效是一种有价值的无创性方法。     

二尖瓣置换加Cox手术对心房颤动转复、心电活动及心功能的影响

目的探讨二尖瓣置换加迷宫手术（ＭＶＲ－ＭＰ）对二尖瓣病变伴心房颤动（房颤）患者的心律转复作用及对心电活动和心功能的影响。方法应用心电图、动态心电图、运动负荷心电图及超声心动图观察２８例ＭＶＲ－ＭＰ患者手术前后心电活动、心功能及运动耐量变化,并与９８例单纯二尖瓣置换术（ＭＶＲ）患者的相应指标比较。术前两组均为二尖瓣病变伴长期房颤患者。结果在随访中ＭＶＲ－ＭＰ组和ＭＶＲ组恢复并维持窦性心律分别为９２．９％和２．０％（Ｐ＜０．０１）;ＭＶＲ－ＭＰ组心律转复后Ｐ波矮小、时限较长,动态及运动心电图未见严重心律失常;两组手术后心功能改善级别分别为２．３７±０．６９和１．４３±０．６７（Ｐ＜０．０１）,所能完成的做功量分别为１０．６７±１．５６和５．２８±０．５９ＭＥＴｓ（Ｐ＜０．０１）,左室射血分数分别为（６５．０±９．２）％及（５１．４±１０．４）％（Ｐ＜０．０１）。结论ＭＶＲ－ＭＰ可使二尖瓣病变伴长期房颤患者恢复窦性心律,可显著提高运动耐量、改善心功能。     

Percutaneous Transvenous Mitral Commissurotomy for Post-Surgical Mitral Restenosis: Acute Outcome and Analysis of Factors Influencing Results

The present study examined the utility of percutaneous transvenous mitral commissurotomy (PTMC) for post-surgical mitral restenosis (Group I, n = 71 patients), and the factors influencing the outcome of the procedure. The results of PTMC were also compared with a group of patients (Group II, n = 70 patients), who underwent PTMC for de novo mitral stenosis. Both the groups were matched for age, pre-procedure mitral valve area and echocardiographic score. PTMC was successful in 60 patients (85%) in group I and in 68 patients (97%) in group II (p < 0.05). However, the final mitral valve area achieved was similar between the two groups (1.8 +/- 0.3 vs. 1.9 +/- 0.2 sq.cm, p = NS). Patients in group I had significantly greater mitral valve calcification (0.6 +/- 0.8 vs. 0.3 +/- 0.6, p < 0.05). Multiple regression analysis of results in patients with post-surgical restenosis revealed that only basal mean pulmonary artery pressure and basal cardiac index correlated significantly with increase in valve area. Mitral valve leaflet mobility, thickness and subvalvular deformity did not correlate significantly with the increase in mitral valve area. CONCLUSION: PTMC is a safe procedure for post-surgical mitral restenosis with negligible complication, with a higher success and significantly lower complication rate than that reported for repeat surgical commissurotomy. Although patients with surgical restenosis had a greater degree of calcification of mitral valve leaflets; only basal mean pulmonary artery pressure and cardiac index significantly influenced the increase in mitral valve area. Increased fibrosis of mitral leaflet following surgery probably adversely influences the results of PTMC for post-surgical mitral restenosis.     

Aspekte der Mitralklappenrekonstruktion bei der chirurgischen Therapie der Mitralklappeninsuffizienz

Mitral valve repair (MVR) is the golden standard for the surgical treatment of mitral valve regurgitation and is superior to mitral valve replacement in terms of perioperative and long-term morbidity and mortality. However, the underlying disease has a significant impact on the functional long-term result of the repair. To evaluate the results of MVR, patients have to be divided by the underlying disease, degenerative mitral valve regurgitation, rheumatic mitral valve regurgitation, ischemic mitral valve regurgitation, and mitral valve regurgitation due to advanced cardiomyopathy. The best functional result for MVR can be achieved for degenerative mitral valve regurgitation (10-year freedom from reoperation for recurrent mitral regurgitation up to 94%) followed by patients with rheumatic mitral valve regurgitation (10-year freedom from reoperation for recurrent mitral regurgitation up to 82%). The progress in the underlying disease of the mitral valve is responsible for recurrent mitral valve regurgitation in these patients. For both underlying disease the 10-year survival rate is > 75%. For patients with ischemic mitral valve regurgitation the functional and survival rates are worse with a 5-year survival rate < 60% and recurrent mitral valve regurgitation > MI (mitral valve insufficiency) II degrees in 28% of patients within 6 months. However, ischemic mitral valve regurgitation is not a disease of the valve, it is a disease of the myocardium; thus, the myocardium is the key factor influencing the functional results of MVR and not pathologic changes in the mitral valve per se. There are no long-term results on patients operated on MI in conjunction with advanced cardiomyopathy; however, the initial mid-term results are encouraging with improved survival.Besides the underlying disease the timing of surgery is of utmost importance for the long-term survival; patients with preoperative NYHA functional class III/IV have a significantly worse short-term and long-term outcome compared to patients operated on for significant mitral valve regurgitation who have only minor or even no symptoms (NYHA class I/II). However, the compliance to undergo complex open-heart surgery via a median sternotomy in asymptomatic patients is very low. Minimally invasive endoscopic mitral valve repair may be an option to increase compliance in these patients, which will result in improved long-term survival with a normal life expectancy.     

保留瓣下结构的二尖瓣替换术

作者报告１９９０年３月～１９９３年５月行保留二尖瓣瓣下结构的二尖瓣替换术９例（其中保留全部瓣下结构４例，保留后瓣及腱索、乳头肌５例）的治疗体会，并对其适应证、禁忌证和术中注意事项进行了讨论。     

二尖瓣置换术中保留后瓣及瓣下结构对左心功能的影响

目的评价保留二尖瓣后瓣及瓣下结构对二尖瓣瓣膜置换患者左心功能的影响。方法64例二尖瓣置换患者随机分为两组,保留二尖瓣后瓣及瓣下结构组（MVRP组）34例,全瓣膜切除瓣膜置换组（MVRC组）30例;术前、术后15d和术后3个月分别应用彩色超声多普勒监测MVRP组、MVRC两组左心功能指标。结果MVRP组左心室舒张末期内径、收缩末期内径、左室功能较MVRC组改善显著（P〈0．05）。结论二尖瓣置换术中保留后瓣及瓣下结构有利于改善瓣膜置换术后左心室功能。     

Functional anatomy of the normal mitral apparatus: a transthoracic,two-dimensional echocardiographic study

BACKGROUND AND AIM OF THE STUDY: Normal mitral valve function relies on integrity of the leaflets, annulus, subvalvular apparatus, and the left ventricle. Echocardiography has contributed significantly to the understanding of normal and abnormal mitral valve function. Thus, plausible pathophysiologic mechanisms have been proposed for various etiologies of mitral regurgitation, based on echocardiographic measurement of a limited number of parameters. This study provides quantitative echocardiographic assessment of various components of the mitral valve-left ventricular (LV) complex. METHODS: Mitral annulus, leaflets, papillary muscles and basal LV posterior wall length were measured at end-systole and end-diastole in 10 adults (7 females, 3 males; mean age 61 +/- 15 years) with structurally and functionally normal hearts. In addition, LV size and function and left atrial and aortic root sizes were measured. RESULTS: Mitral valve competence in these normal hearts was achieved by systolic reduction in LV volume, diameter and length of 66%, 31% and 18%, respectively. The LV posterior wall (from mitral annulus to origin of the posteromedial papillary muscle) was shortened by 32%. The mitral annulus likewise showed a reduction in diameter of 6% in anteroposterior and 13% in mediolateral planes. Anterior mitral valve leaflet apposed with posterior leaflet by 23% in length in systole, whereas the papillary muscle shortened by 34%. The interpapillary muscle distance decreased by 51% in systole. CONCLUSION: These data provide echocardiographic reference values for various components of the mitral valve-LV complex in normal adults. Further studies are needed to identify the relative significance of each of these components in the pathogenesis of mitral regurgitation of various etiologies.