限制性二尖瓣成型联合cabg治疗缺血性二尖瓣返流

1、限制性二尖瓣成型联合cabg治疗缺血性二尖瓣返流缺血性二尖瓣返流（ischemic mitral regurgitation, IMR）-CAD、心肌缺血/心肌梗塞引起的乳头肌功能不全、左心功能不全、瓣环扩大等造成的二尖瓣关闭不全。这类病人在进行心脏冠状动脉搭桥手术时常常需要考虑是否同时处理IMR。MVR 是治疗二尖瓣关闭不全的有效手段，但术后常需要长期或短期抗凝，出血或/和血栓栓塞的发生率可达2-7%/年（1），人工瓣膜本身还可能发生心内膜炎、瓣周漏、溶血等，严重影响病人的远期效果。 良好的二尖瓣成型技术-治疗IMR的有效手段，-完全避免与人工瓣相关的并发症-降低手术死亡率-提高患者生存质量

2、和远期效果。临床资料一般资料： 72 例 伴有中重度IMR（3-4+，3.50.6）的冠心病人接受了同时CABG+限制性二尖瓣成型男:女 = 59 : 13年龄 55-83 ( 67.25.7) 岁，70岁以上病人33例心电图: 陈旧性Q波心肌梗塞-66例TTE : 中-重度返流 (3+) 40 例重度返流 (4+) 32 例LVEDD 55-81 (64.211.5) mm,LAD 52-74(58.06.2)mmLVEF 45% 41例。同时合并三尖瓣中重度返流10例。CAG：双支病变7例，65例三支病变，同时合并LM狭窄 16例。 同时合并左心室壁瘤18例。手术前心功能 NYHA II级

3、15例、III和IV级分别为42例和15例合并疾病: 高血压病37例，糖尿病29例，心衰史41例，慢性心房纤颤10例，肾功能异常17例，脑中风史16例。5例严重左主干病变伴术前不稳定心绞痛主动脉内球囊反搏（IABP）1：1辅助下急诊手术。方 法常规放置Swan-Gaze导管，监测PA, PCWP术中（TEE）：评价二尖瓣功能状态、心脏功能和成型效果。72例均在全麻体外循环下经胸骨正中切口手术。开胸后先取左乳内动脉，同时取桡动脉和大隐静脉备用。常规 CPB。阻断主动脉，心肌保护采用经主动脉根部顺行灌注含血心肌保护液，结合经“桥”灌注。合并主动脉瓣病变者切开升主动脉，经冠状动脉开口直接冷灌。手术中

4、先处理室壁瘤，然后进行冠状动脉远端吻合，再经右房房间隔途径暴露和处理二尖瓣。手术中TEE观察二尖瓣膜成型效果。术中探查结合TEE见二尖瓣膜返流的原因 二尖瓣环扩大引起的IMR-Carpentie I型- 54例手术中探查结合TEE-二尖瓣返流原因 心腔明显扩大、乳头肌肉移位引起腱索乳头肌功能而导致二尖瓣返流-Carpentier IIIb -18例手术中用二尖瓣成型的测瓣器，根据二尖瓣前后叶交界间的距离和前叶的面积，测得所需成型环的大小，实际植入的二尖瓣成型环均比测量的小一到二号2-0 Ticron线不带垫片间断褥式缝合植入二尖瓣成型环，注水实验观察二尖瓣返流矫正情况。同时主动脉置换者在升主动

5、脉一次阻断下完成近端吻合，单纯二尖瓣成型者在升主动脉侧壁钳下完成近端吻合。主动脉开放前先开放乳内动脉桥，并左心排气主动脉开放后进行三尖瓣成型。 结 果72例均放置二尖瓣成型环（16例为C 型环，56例为0型全环）冠状动脉远端吻合人均3.41.3（3-6）个。应用左乳内动脉71例，21支静脉桥为序贯搭桥。同时行主动脉瓣置换9例，三尖瓣成型10例，室壁瘤线性切除6例，心内补片左室成型12例。主动脉阻断时间55-126 min，平均7822 min；CPB时间 78-170 min，平均12239 min。 手术中成型后TEE：二尖瓣无和微量反流28和35例，轻度返流6例，轻-中度返流3例，中-重度

6、返流1例（再次CPB下行二尖瓣置换，原位保留全部二尖瓣装置植入27#生物瓣）。手术后共18例带IABP回ICU，IABP支持15-112小时。15例在手术后72小时内拔除IABP。 手术后并发症二次开胸止血2例；新发房颤22例（20例药物治疗后转成窦性心律）9例病人拔除气管插管后因低氧血症需无创呼吸机辅助 ，1例需再次气管插管呼吸机辅助；肾功能损害加重行 CRRT 4 例；脑中风1例；下肢切口感染2例 围手术期死亡3例：低心排合并多脏器功能衰竭2例，手术后急性肾功能衰竭伴肺部严重感染1例，分别在术后3、7和14天死亡，手术死亡率4.2%68例（转成二尖瓣置换1例除外）康复出院。 随 访手术后随

7、访6-60个月（平均 22.8月）， 随访满6月的66例（死亡2例，心源性死亡1例） 6-12月的66例（死亡2例，非心源性死亡） 12月的56例（累计心源性死亡3例） 24月的40例（累计心源性死亡5例）。患者心功能改善，心绞痛均消失。手术后3、6、12、24月，分别经胸超声心动图检查（表1），手术后IMR均得到明显改善，左房和左室舒张末期内径明显缩小，随访期间无二次手术。表1 二尖瓣成型手术前后超声检查结果 术前 术终 术后2周 3月 6月 12 月 24月 P value病人总数 72 71* 71 71 66 56 40 累计死亡数 - - 3 3 5 7 8 生存率% 96 96 9

8、2 88 80二尖瓣反流程度3.30.6 0.40.4 0.40.4 0.50.6 0.50.6 0.70.7 0.70.6 0.01EF% 5014 - 5415 5317 5414 5418 5515 0.01LVEDD 6411 - 5710 5511 569 5712 5514 0.01LA 586 - 535 497 506 486 497 0.01*1例转成二尖瓣置换除外讨 论一、手术指征： 与单纯搭桥相比，同时搭桥和心脏瓣膜手术明显增加手术死亡率2，但如果不处理已经存在的明显IMR，又明显降低远期生存率。 因此手术中决定是否处理IMR明显影响手术效果。 术中TEE评价IMR时，应

9、保证心脏良好的前后负荷，否则可能低估IMR的程度，影响手术方案2。 虽然 Seipelt5等的262例病人结果显示搭桥同时二尖瓣成型置换虽不影响手术后早期效果，但缺血性二尖瓣病变组手术死亡率明显高于非缺血组（19.5% vs 6.7%, P=0.002）。Bonacchi等6分析了180例伴LV功能减退和IMR病人，结果显示，对轻-中度IMR，单纯搭桥手术后生存率满意，IMR也得到明显改善，但远期无事件生存率低于同时MVP病人，提示即使轻-中度IMR，也应该积极处理。下壁MI-IMR的重要危险因素本组56%有明确陈旧性下壁Q波心肌梗塞，主要是因为下壁心梗后的心室重构，严重影响二尖瓣装置的几何形

10、状，导致后乳头肌向外侧移位，腱索牵拉过紧影响二尖瓣的关闭，产生IMR。Kumanohoso7分析了103例心肌梗塞病人，61例前壁，42例下壁心梗，虽然下壁MI对LV功能影响小于前壁MI，但下壁心梗病人IMR的发生率38%（16/42）和返流程度（返流面积）（10.1%+7.5%）均明显高于前壁心梗(10%)（6/61，P.0001)，（4.4%7.0%, P=.0002）。作者体会/经验冠心病人伴轻-中度IMR，如果左房和左室大小正常，左室功能也正常，可以仅行冠状动脉搭桥但对中度和中度以上的IMR者，伴心室功能已经减退，特别是心脏已经明显扩大者，需要积极处理；对有陈旧性下壁Q波心梗，左室功能

11、明显减退病人的IMR处理应更加积极，以提高手术后远期的无事件生存率。对存在多种手术危险因素的中度IMR病人，单纯搭桥可能降低手术死亡率8,需要综合考虑，决定是否同时处理IMR。冠状动脉靶血管的条件也是影响手术指征的重要因素对手术前左心室EF60岁，两组的远期生存率无明显差异。本组1例病人关胸前TEE显示成型效果不满意，再次CPB下瓣膜置换，未增加术后并发症。限制性二尖瓣成型 Bolling 最早提出采用限制性二尖瓣成型治疗终末期心肌病伴重度二尖瓣反流，取得了较好的早期效果3但关于缺血性心脏病伴中重度二尖瓣反流的病人行冠状动脉搭桥和限制性二尖瓣成型的报道不多本组二尖瓣环扩大引起的IMR即所谓Ca

12、rpentie I型IMR（本组54例），以及因心腔明显扩大，乳头肌肉移位引起腱索乳头肌功能而导致二尖瓣返流（Carpentier IIIb型）（本组18例）病人，在搭桥同时均植入二尖瓣成型环，效果满意。我们手术中在成型环植入前，先在左右纤维三角处各缝一针褥式缝合，再根据两纤维三角之间的距离和二尖瓣前瓣叶的大小测得成型环大小，实际上采用的成型环比测得的小一到二个号，达到限制性二尖瓣成型。Geidel也强调Downsizing 二尖瓣成型可以提高远期效果12。本组男性病人多采用28#30#的成型环，女性病人多采用26-28#的成型环，平均随访22.8月，中期临床效果满意。Bax11等报告51例中

13、-重度IMR伴左室功能减退的冠状动脉搭桥病人，手术中采用比正常小两号的成型环，手术死亡率5.6%，手术后左房左室均明显缩小，随访两年生存率84% 。二尖瓣成型环的选择对称成型环：“O”型和“C”型，虽然在IMR主要是后瓣环扩大，理论上采用“C型环”将后瓣环缩小即能纠正IMR，但二尖瓣的前后径扩大也是导致前后瓣叶不能满意对合的重要原因，因此，“O型”环可以保证更满意的远期效果。二尖瓣非对称成型环（ETlogix）用于治疗IMR，解剖上更加符合生理，临床应用的近期效果十分满意，远期效果还需要时间证实。“”型环能更好的维持二尖瓣环前后径距离IMR的治疗有二尖瓣成型和二尖瓣置换。从发病机制来看，IMR

14、主要是因为瓣环明显扩大或瓣下装置（腱索、乳头肌）异常，而瓣叶常常无明显异常病变。Reece等14报告110 IMR中，54例病人搭桥+二尖瓣成型，56例搭桥+换瓣（保留瓣下装置），但手术死亡率有明显差异（1.9% vs 10.7%），提示即使瓣膜置换病人均保留瓣下装置，瓣膜修复仍有明显优势。二尖瓣成型可明显改善左室功能和几何形状，成型组的远期生存率明显高于换瓣组6。所以对IMR病人应尽可能争取行瓣膜成 Intraoperative TEEPre-ImplantPost-ImplantKang等8分析了107例中重度IMR病人，50例成型，57例仅搭桥，成型组手术死亡率12%，明显高于单纯搭桥组

15、(2%),但五年生存率相似（88%5% versus 87%6%），多元回归分析显示：高龄、心功能差、房颤是手术死亡的独立预测因素(P0.05)。在重度IMR病人，成型后所有病人IMR均明显改善，而单纯搭桥组仅67%病人的IMR得到改善(P0.001)。但在中度IMR病人，两组IMR改善率相似(75% versus 67%, P=NS)，提示二尖瓣成型可以有效改善IMR，但对合并有高龄、房颤等手术高危因素的中度IMR病人，搭桥同时二尖瓣成型可增加手术死亡率。 年龄是影响手术效果的重要因素之一15，高龄病人手术后易发生肺部并发症，本组手术后8例病人拔除气管插管后因低氧血症需无创呼吸机辅助，其中6

16、例为70岁以上病人。故手术后加强肺部并发症的防止，对高龄病人更为重要。手术后低心排仍是主要的死亡原因（本组两例），对有明显低心排表现，及早应用主动脉内球囊反搏，帮助稳定血液动力学。本组对手术前LVEF 70 in 33.ECG: old MI with q wave in 56.TTE : Moderate-severe (3+) 40 Severe (4+) 32 LVEDD 55-81 (64.211.5) mm, LAD 52-74(58.06.2)mm LVEF 45% 41Morderate-severe TVR in 10CAG：double-vessel disease in 7

17、, triple-vessel in 65, severe LM disease in 16 LV aneurysm in 18NYHA: class in 15, class III in 42 and class IV in 15. Co morbidity: high blood pressure 37 diabetes mellitus 29 history of heart failure 41 history of stroke 16 chronic AF 10 renal dysfunction 17Emergency op in 5 severe LM disease with

18、 unstable angina with IABPMethods Swan-Gaze monitored PA and PCWP TEE assessed LV function , degree of MR and effect of MVPMidline sternotomy was preferred, IMA and GSV were harvested, RA was used selectivelyCPB with intermittent antegrade cardioplegia combined with “graft” perfusion. Direct CA orif

19、ice perfusion was performed if AI was present Ventricular aneurysm was first disposed, then distal anastomosis was performed, the right atrium was opened and MVR was performed through a transseptal approach. Intraoperative exploration and TEE identified the mechanisms of MR. TEE evaluated the effect

20、 of MVP. Annular dilatation (Carpentie I) in 54Exploration and TEE identify the mechanisms of MR Cardiac chamber dilatation /transposition and dysfunction of chordae tendineae /papillary muscle (Carpentier type IIIb) in 18 MVP ring size was determined by standard measurement of the intertrigonal dis

21、tance and anterior leaflet height. Restrictive annuloplasty was performed with an undersized semirigid ring (downsizing 1-2 sizes). The rings were anchored using multiple (1416) deep U-shaped stitches of 2-0 Ticron without mattress. Precise evaluation of preserved valve symmetry and proper leaflet c

22、oaptation was obtained by ventricular filling with saline solution. other concomitant procedures and proximal CABG anastomosis were performed.Results All had Mitral annuloplasty ring (“C” type in 16 and “O” type in 56). Average number of graft was 3.41.3(range, 3-6). Concomitant procedures AVR 9 , T

23、VP 10 linear repair of LV aneurysm 6 SVR (patch endoaneurysmorrhaphy) 12Mean CPB time 12239 min (range, 78-170) mean X-clamp 7822 min (range, 55- 126).Intraoperative TEE: no residual MR in 28, minimal 35 1+ in 6, 12+ in 3 2+-3+ MR in 1 (who received a 27# MVP with entire preservation of subvalvular

24、apparatus in situ)18 cases needed IABP support when entered ICU, IABP time was 15 -112h, 15 cases were supported less than 72h.Post-op complications Re-operation for bleeding in 3 casesAF in 22 cases, 20 converted to SR by medicationre-intubation in 1, non-invasive breathing machine was used in 9, t

25、emporary dialysis in 4stroke in 1 and wound infection of lower extremities in 2Perioperative mortality was 4.2% (3 patients): LCOS with multi-organ failure in 2 patients, acute renal failure with severe pulmonary infection in 1. 68 cases (except MVR in 1 case) discharged. Follow-up The follow-up tim

26、e was 6-60 months (mean, 22.8). The follow-up transthoracic UCG (3,6,12,24 months post-op) showed that the IMRs were rectified satisfactory with an improved cardiac function (Table 1). All patients were free of angina pectoris and re-operation for recurrent MR . Table 1. Follow-up outcomes and pre-

27、/post-op UCG Pre- post- 2w post- 6m 12m 24m P N 72 71* 71 71 66 56 40 N of death - - 3 3 5 7 8 Survival(%) 96 96 92 88 80IMR 3.30.6 0.40.4 0.40.4 0.50.6 0.50.6 0.70.7 0.70.6 0.01EF% 4514 - 5415 5317 5414 5418 5515 0.01LVEDD 6411 - 5710 5511 569 5712 5514 0.01LA 586 - 535 497 506 486 497 0.01*1 case

28、converted to MVR was excludedDiscussionIndications for IMR:CABG Combined with valvular procedure had a higher mortality; but CABG alone came out with a lower long-term survival rate.IMR effected surgical outcomes. Preload and afterload conditions influenced the severity of MR presented on TEE. Seipe

29、lt et al. reported on a retrospective analysis of 262 patients who received either CABG and MVP or CABG alone, the former had a higher motality (19.5% vs 6.7%, P=0.002). Bonacchi et al. analyzed 180 patients with IMR and LV dysfunction, in mild-moderate IMR group, CABG brought a low mortality and a

30、low IMR grade, but long-term survival rate without cardiac event was lower than those received combined CABG and annuloplasty, which indicated that even mild-moderate IMR should be rectified aggressively. Posterior MI -an important risk factor of IMRIn this study, 56% cases had posterior MI with q w

31、ave. The mechanisms: LV remodeling after posterior MI had a more severe negative impact on the geometry of mitral apparatus, especially on the posterior papillary muscles and chorda tendineae which were dragged laterally, any forms of mis-coaptation of MV might lead to the presence of regurgitation.

32、 Kumanohosos report about 103 MI patients (61 anterior MI and 42 posterior MI ) indicated that posterior MI had a less impact on LV function but a higher impact on IMR (rate: 38%, 16/42 Vs 10%, 6/61, P.0001; degree: 10.17.5% Vs 4.47.0%, P=0.0002) Kang: 107 3-4+ IMR.severe IMR was attenuated dramatic

33、ally by CABG combined with MVP, only 67% in CABG alone (P0.001); but to moderate IMR, the rate was similar (75% Vs 67%, P=NS).-Only 4+ IMR need MVPOur experiencesCAD patient with a normal LV chamber and function who has a mild-moderate IMR-CABG Moderate-severe IMR with decreased LV function, especia

34、lly with dilated cardiac chambers, CABG+ annuloplastyModerate-severe IMR with an old posterior q wave MI and with a severe decreased LV function, CABG+ MVP or MVR must be performedFor high risk patient with moderate IMR, CABG alone had a lower motality, an overall evaluation-Balance the risk and ben

35、ifits. The condition of target vessels is an important factorFor CAD patients with low LVEF (30%), revascularization was preferred aggressively if patients had good target vessels, but if diffused coronary was present, revascularization should be performed cautiously. Operative experiences: importan

36、t in choosing operative approach For aged cases, MVR was a good alternative if MVP was not reliable. In this study, 1 patient was converted to MVR since TEE showed that the annuloplasty was unsatisfactory. Thouranis reported that combined procedures increased operative risks, but in 60 years group,

37、long-term survival rate was of no difference between MVP and MVR groups.Restrictive annuloplasty Bolling - frist introduced for end-stage cardiomyopathy with severe MR- with a good short-term results. The reports about the treatment of ischemic cardiomyopathy by CABG combined with restrictive MVP ar

38、e scare.In this study, IMR was divided 2 groups : annular dilatation (Carpentier type I in 54 cases); dilatation of cardiac chamber, displacement of papillary muscles and dysfunction of chordae tendineaes (Carpentier type IIIb in 18 cases). Annuloplasty ring was applied in each case.MVP ring - downs

39、izing by 1 to 2 ring sizes.In this study, 28#-30# rings for men and 26#-28# for female. The mean follow-up 22.8 months with good mid-term resultsBax analyzed 51 cases undergoing CABG and restrictive annuloplasty with stringent downsizing of the mitral annulus (by 2 sizes). Early operative mortality

40、was 5.6%, left atrium and LV dimension reduced dramatically; during 2-year follow-up, only 1 patient needed re-operation for recurrent MR; 2-year survival rate was 84%.Alternative of MVP ringSymmetrical ring-“O” and “C type: Although annular dilatation is mainly caused by posterior annular dilatation and “C” type ring would rectify the IMR through diminishing posterior annulus, increased A-P distance is also one of the important risk factors that lead to the failure of leaflets coaptation, so “O” type may guarantee be