今日の臨床サポート 今日の臨床サポート

著者: 中谷 敏 社会福祉法人恩賜財団 大阪府済生会千里病院

監修: 伊藤浩 川崎医科大学総合内科学3教室

著者校正/監修レビュー済:2024/09/18
患者向け説明資料

改訂のポイント:
  1. 外科的手術が困難な場合の選択肢としてのMitraClipを追記した。

概要・推奨   

  1. 軽症の逆流は無症状である。高度となり血行動態に影響が出るほどになってくると、労作時息切れや動悸が出現する。心房細動が発症すると、自覚症状が顕著となる。
  1. 腱索断裂に伴う急性僧帽弁閉鎖不全症では、激しい左心不全症状が出現する。
  1. 聴診で収縮期雑音を聴取すれば、僧帽弁閉鎖不全症を考える(推奨度1)
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  1. 閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります
  1. 閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となり
  1. 閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契
  1. 閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となりま

病態・疫学・診察 

疾患情報(疫学・病態)  
  1. 僧帽弁は弁輪、弁尖、腱索、乳頭筋、その付着する左室からなる僧帽弁複合体がうまく機能することにより、スムーズな開閉を行っている。僧帽弁閉鎖不全症とは、僧帽弁複合体の一部に障害が起き、弁尖間の接合が阻害されることにより僧帽弁逆流が生じる状態である。
  1. 健常人でも、心エコー図検査で軽度の僧帽弁逆流を認めることはしばしばある。これらは放置してよい。
  1. 僧帽弁閉鎖不全症は、弁尖、腱索、乳頭筋の器質的異常のために生じる一次性僧帽弁閉鎖不全症と、左室や左房の拡大または機能不全によって生じる二次性僧帽弁閉鎖不全症に分けられる。リウマチ熱が激減した昨今、一次性僧帽弁閉鎖不全症で最も多い原因は、変性(粘液腫様変性)に基づく弁尖逸脱であろう。多くの腱索断裂も、変性に伴うものと思われる。
  1. 僧帽弁逸脱は、軽度のものも含めればまれな病態ではなく、1,000人中20~60人に認められるという。
  1. 高度の僧帽弁閉鎖不全症では左房容量負荷を生じ、左房容量負荷は肺静脈圧増加を介して肺高血圧を惹き起こし、肺うっ血や運動時息切れを生じることになる。
    また、肺高血圧は、右心系への圧負荷によって右心系を拡大せしめる。拡大した右心室、右心房は、三尖弁輪拡大や右室内tetheringによって三尖弁逆流を起こす(<図表>)。高度の三尖弁逆流は上・下大静脈拡張を生じ、肝腫大、下腿浮腫を来す。
  1. 左房拡大は心房細動を惹き起こし、さらに、左房拡大に伴う弁輪拡大は弁尖接合を浅くして僧帽弁逆流量を増加させる。増加した逆流は、再び左房容量負荷となって弁輪を拡大させ、悪循環に入る。
  1. 病初期では、左室駆出率は正常またはそれ以上に保たれるが、左室拡大が顕著になり代償機転が破綻するにつれ、次第に駆出率が低下してくる。
問診・診察のポイント  
  1. 軽症の逆流は無症状である。高度となり血行動態的に影響が出るほどになってくると、労作時息切れや動悸が出現する。心房細動が発症すると、自覚症状が顕著となる。

これより先の閲覧には個人契約のトライアルまたはお申込みが必要です。

最新のエビデンスに基づいた二次文献データベース「今日の臨床サポート」。
常時アップデートされており、最新のエビデンスを各分野のエキスパートが豊富な図表や処方・検査例を交えて分かりやすく解説。日常臨床で遭遇するほぼ全ての症状・疾患から薬剤・検査情報まで瞬時に検索可能です。

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文献 

Messas E, Guerrero JL, Handschumacher MD, Chow CM, Sullivan S, Schwammenthal E, Levine RA.
Paradoxic decrease in ischemic mitral regurgitation with papillary muscle dysfunction: insights from three-dimensional and contrast echocardiography with strain rate measurement.
Circulation. 2001 Oct 16;104(16):1952-7. doi: 10.1161/hc4101.097112.
Abstract/Text BACKGROUND: Ischemic mitral regurgitation (MR) was first ascribed to papillary muscle (PM) contractile dysfunction. Current theories include apical leaflet tethering caused by left ventricular (LV) distortion, but PM dysfunction is still postulated and commonly diagnosed. PM contraction, however, parallels apical tethering, suggesting the hypothesis that PM contractile dysfunction can actually diminish MR due to ischemic distortion of the inferior base alone.
METHODS AND RESULTS: We therefore occluded the proximal circumflex circulation in 7 sheep while maintaining PM perfusion, confirmed by contrast echocardiography. By 3D echocardiography, we measured the tethering distance between the ischemic medial PM tip and anterior annulus and LV ejection volume to give MR (by subtracting flowmeter LV outflow). In 6 sheep without initial MR, inferior ischemia alone produced PM tip retraction with restricted leaflet closure and mild-to-moderate MR (regurgitant fraction, 25.2+/-2.8%). Adding PM ischemia consistently decreased MR and tethering distance (5.2+/-0.3 to 1.4+/-0.3 mL; +3.8+/-0.5 mm to -2.2+/-0.7 mm axially relative to baseline; P<0.001) as PM strain rate decreased from +0.78+/-0.07 per second (contraction) to -0.42+/-0.06 per second (elongation, P<0.001) and leaflet tenting decreased. In one sheep, prolapse and MR resolved with inferior ischemia and recurred with PM ischemia.
CONCLUSIONS: PM contractile dysfunction can paradoxically decrease MR from inferobasal ischemia by reducing leaflet tethering to improve coaptation. This emphasizes the role of geometric factors in ischemic MR mechanism and potential therapy.

PMID 11602500
日本循環器学会:2020年改訂版 弁膜症治療のガイドライン.
Ling LH, Enriquez-Sarano M, Seward JB, Orszulak TA, Schaff HV, Bailey KR, Tajik AJ, Frye RL.
Early surgery in patients with mitral regurgitation due to flail leaflets: a long-term outcome study.
Circulation. 1997 Sep 16;96(6):1819-25. doi: 10.1161/01.cir.96.6.1819.
Abstract/Text BACKGROUND: The optimal timing for surgery in patients with mitral regurgitation is disputed. Because of the frequency of left ventricular dysfunction, which is difficult to predict, early surgery has been recommended, but its potential benefits have not been demonstrated.
METHODS AND RESULTS: The outcomes of 221 patients (mean age, 65 +/- 13 years; 71% males) with flail leaflets diagnosed with two-dimensional echocardiography between 1980 and 1989 who were eligible for operation were analyzed. Group I comprised 63 patients who had early mitral valve surgery (within 1 month after diagnosis). Group II comprised 158 patients initially treated conservatively (80 of whom were operated on later). Group I patients were younger (P=.009), had more symptoms (P<.0001), and were more frequently in atrial fibrillation (P=.023) than group II patients. There was no difference in ejection fraction between the groups. The early surgery strategy was followed by an improved overall survival rate (P=.028) and a lower incidence of cardiovascular deaths (P=.025), congestive heart failure (P=.046), and new chronic atrial fibrillation (P=.032), as confirmed by multivariate analysis (adjusted risk ratios of 0.31, 0.18, 0.38, and 0.05, respectively; all P<.02).
CONCLUSIONS: In patients with mitral regurgitation due to flail leaflets, the strategy of early surgery versus conservative management is associated with an improved long-term survival rate, decreased cardiac mortality, and decreased morbidity after diagnosis. This outcome advantage suggests that early surgery is a reasonable treatment option to be considered in low-risk candidates with repairable valves and severe mitral regurgitation.

PMID 9323067
Tribouilloy CM, Enriquez-Sarano M, Schaff HV, Orszulak TA, Bailey KR, Tajik AJ, Frye RL.
Impact of preoperative symptoms on survival after surgical correction of organic mitral regurgitation: rationale for optimizing surgical indications.
Circulation. 1999 Jan 26;99(3):400-5. doi: 10.1161/01.cir.99.3.400.
Abstract/Text BACKGROUND: Surgical correction of mitral regurgitation in patients with no or mild symptoms remains controversial, particularly because the impact of preoperative symptoms on postoperative outcome is unknown.
METHODS AND RESULTS: The long-term outcome of 478 patients with organic mitral regurgitation (199 in NYHA functional class I/II and 279 in class III/IV before surgery) operated on between 1984 and 1991 was analyzed. In patients in NYHA class I/II before surgery compared with those in class III/IV, postoperative long-term survival was higher (at 10 years, 76+/-5% versus 48+/-4%, P<0.0001), with lower operative mortality (0.5% versus 5.4%, P=0.003) and better late survival (P<0.0001). Comparison of observed and expected survival showed identical curves in patients in class I/II before surgery (P=0.18), whereas excess mortality was observed in patients in class III/IV before surgery (P<0.0001). Excess mortality associated with severe symptoms was also confirmed in all subgroups (all P<0.003) and in multivariate analysis (P=0.0036; adjusted hazard ratio [95% CI], 1.81 [1.21 to 2.70]).
CONCLUSIONS: In patients with organic mitral regurgitation, preoperative functional class III/IV symptoms are associated with excess short- and long-term postoperative mortality independently of all baseline characteristics. These data should lead to consideration of surgical correction of severe organic mitral regurgitation when no or minimal symptoms are present in patients at low operative risk, especially if repair is feasible.

PMID 9918527
Enriquez-Sarano M, Schaff HV, Orszulak TA, Tajik AJ, Bailey KR, Frye RL.
Valve repair improves the outcome of surgery for mitral regurgitation. A multivariate analysis.
Circulation. 1995 Feb 15;91(4):1022-8. doi: 10.1161/01.cir.91.4.1022.
Abstract/Text BACKGROUND: Mitral valve repair has been suggested as providing a better postoperative outcome than valve replacement for mitral regurgitation, but this impression has been obscured by differences in baseline characteristics and has not been confirmed in multivariate analyses.
METHODS AND RESULTS: The outcomes in 195 patients with valve repair and 214 with replacement for organic mitral regurgitation were compared using multivariate analysis. All patients had preoperative echocardiographic assessment of left ventricular function. Before surgery, patients with valve repair were less symptomatic than those with replacement (42% in New York Heart Association functional class I or II versus 24%, respectively; P = .001), had less atrial fibrillation (41% versus 53%; P = .017), and had a better ejection fraction (63 +/- 9% versus 60 +/- 12%, P = .016). After valve repair, compared with valve replacement, overall survival at 10 years was 68 +/- 6% versus 52 +/- 4% (P = .0004), overall operative mortality was 2.6% versus 10.3% (P = .002), operative mortality in patients under age 75 was 1.3% versus 5.7% (P = .036), and late survival (in operative survivors) at 10 years was 69 +/- 6% versus 58 +/- 5% (P = .018). Late survival after valve repair was not different from expected survival. After surgery, ejection fraction decreased significantly in both groups but was higher after valve repair (P = .001). Multivariate analysis indicated an independent beneficial effect of valve repair on overall survival (hazard ratio, 0.39; P = .00001), operative mortality (odds ratio, 0.27; P = .026), late survival (hazard ratio, 0.44; P = .001), and postoperative ejection fraction (P = .001).
CONCLUSIONS: Valve repair significantly improves postoperative outcome in patients with mitral regurgitation and should be the preferred mode of surgical correction. The low operative mortality is an incentive for early surgery before ventricular dysfunction occurs.

PMID 7850937
Mohty D, Orszulak TA, Schaff HV, Avierinos JF, Tajik JA, Enriquez-Sarano M.
Very long-term survival and durability of mitral valve repair for mitral valve prolapse.
Circulation. 2001 Sep 18;104(12 Suppl 1):I1-I7. doi: 10.1161/hc37t1.094903.
Abstract/Text BACKGROUND: Mitral regurgitation (MR) due to mitral valve prolapse (MVP) is often treatable by surgical repair. However, the very long-term (>10-year) durability of repair in both anterior leaflet prolapse (AL-MVP) and posterior leaflet prolapse (PL-MVP) is unknown.
METHODS AND RESULTS: In 917 patients (aged 65+/-13 years, 68% male), surgical correction of severe isolated MR due to MVP (679 repairs and 238 replacements [MVRs]) was performed between 1980 and 1995. Survival after repair was better than survival after MVR for both PL-MVP (at 15 years, 41+/-5% versus 31+/-6%, respectively; P=0.0003) and AL-MVP (at 14 years, 42+/-8% versus 31+/-5%, respectively; P=0.003). In multivariate analysis adjusting for predictors of survival, repair was independently associated with lower mortality in PL-MVP (adjusted risk ratio [RR] 0.61, 95% CI 0.44 to 0.85; P=0.0034) and in AL-MVP (adjusted RR 0.67, 95% CI 0.47 to 0.96; P=0.028). The reoperation rate was not different after repair or MVR overall (at 19 years, 20+/-5% for repair versus 23+/-5% for MVR; P=0.4) or separately in PL-MVP (P=0.3) or AL-MVP (P=0.3). However, the reoperation rate was higher after repair of AL-MVP than after repair of PL-MVP (at 15 years, 28+/-7% versus 11+/-3%, respectively; P=0.0006). From the 1980s to the 1990s, the RR of reoperation after repair of AL-MVP versus PL-MVP did not change (RR 2.5 versus 2.7, respectively; P=0.58), but the absolute rate of reoperation decreased similarly in PL-MVP and AL-MVP (at 10 years, from 10+/-3% to 5+/-2% and from 24+/-6% to 10+/-2%, respectively; P=0.04).
CONCLUSIONS: In severe MR due to MVP, mitral valve repair compared with MVR provides improved very long-term survival after surgery for both AL-MVP and PL-MVP. Reoperation is similarly required after repair or replacement but is more frequent after repair of AL-MVP. Recent improvement in long-term durability of repair suggests that it should be the preferred mode of surgical correction of MVP whether it affects anterior or posterior leaflets and is an additional incentive for early surgery of severe MR due to MVP.

PMID 11568020
Moss RR, Humphries KH, Gao M, Thompson CR, Abel JG, Fradet G, Munt BI.
Outcome of mitral valve repair or replacement: a comparison by propensity score analysis.
Circulation. 2003 Sep 9;108 Suppl 1:II90-7. doi: 10.1161/01.cir.0000089182.44963.bb.
Abstract/Text BACKGROUND: There are no randomized trials comparing outcomes after mitral valve (MV) repair and replacement. Propensity scoring is a powerful tool that has the potential to reduce selection bias in nonrandomized studies.
METHODS: From the BC Cardiac Registries, 2,060 patients presented for MV surgery, with or without CABG between 1991 and 2000. We then identified 322 MV repairs who were then matched by propensity score to an equal number of MV replacement patients. We compared survival and freedom from re-operation outcomes using Cox proportional hazards model analysis. Multivariable analysis was then used to compare outcomes in 358 MV repair patients with 352 MV replacement patients who had undergone chordal sparing surgery.
RESULTS: The comparison groups generated using propensity scores were well balanced with respect to all collected baseline risk factors. Median follow-up time was 3.4 years. Patients undergoing MV repair had significantly improved survival (RR 0.46; 95% CI, 0.28 to 0.75) but a trend toward more re-operations (RR 2.11; 95% CI, 1.00 to 4.47) compared with patients undergoing replacement. Mitral valve repair patients still had better survival (RR 0.52; 95% CI, 0.32 to 0.85) compared with MV replacement patients who had undergone chordal sparing surgery.
CONCLUSIONS: We used propensity score methods to reduce selection bias in a population-based cohort of patients undergoing MV repair/replacement. Repair was associated with better survival, but a trend to increased re-operation.

PMID 12970215
Enriquez-Sarano M, Freeman WK, Tribouilloy CM, Orszulak TA, Khandheria BK, Seward JB, Bailey KR, Tajik AJ.
Functional anatomy of mitral regurgitation: accuracy and outcome implications of transesophageal echocardiography.
J Am Coll Cardiol. 1999 Oct;34(4):1129-36. doi: 10.1016/s0735-1097(99)00314-9.
Abstract/Text OBJECTIVES: This study was performed to determine the accuracy and outcome implications of mitral regurgitant lesions assessed by echocardiography.
BACKGROUND: In patients with mitral regurgitation (MR), valve repair is a major incentive to early surgery and is decided on the basis of the anatomic mitral lesions. These lesions can be observed easily with transesophageal echocardiography (TEE), but the accuracy and implications for outcome and clinical decision-making of these observations are unknown.
METHODS: In 248 consecutive patients operated on for MR, the anatomic lesions diagnosed with TEE were compared with those observed by the surgeon and those seen on 216 transthoracic echocardiographic (TTE) studies, and their relationship to postoperative outcome was determined.
RESULTS: Compared with surgical diagnosis, the accuracy of TEE was high: 99% for cause and mechanism, presence of vegetations and prolapsed or flail segment, and 88% for ruptured chordae. Diagnostic accuracy was higher for TEE than TTE for all end points (p < 0.001), but the difference was of low magnitude (<10%) except for mediocre TTE imaging or flail leaflets (both p < 0.001). The type of mitral lesions identified by TEE (floppy valve, restricted motion, functional lesion) were determinants of valve repairability and postoperative outcome (operative mortality and long-term survival; all p < 0.001) independent of age, gender, ejection fraction and presence of coronary artery disease.
CONCLUSIONS: Transesophageal echocardiography provides a highly accurate anatomic assessment of all types of MR lesions and has incremental diagnostic value if TTE is inconclusive. The functional anatomy of MR defined by TEE is strongly and independently predictive of valve repairability and postoperative outcome. Therefore, the mitral lesions assessed by echocardiography represent essential information for clinical decision making, particularly for the indication of early surgery for MR.

PMID 10520802
Bonow RO, Carabello BA, Chatterjee K, de Leon AC Jr, Faxon DP, Freed MD, Gaasch WH, Lytle BW, Nishimura RA, O'Gara PT, O'Rourke RA, Otto CM, Shah PM, Shanewise JS; 2006 Writing Committee Members; American College of Cardiology/American Heart Association Task Force.
2008 Focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease): endorsed by the Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons.
Circulation. 2008 Oct 7;118(15):e523-661. doi: 10.1161/CIRCULATIONAHA.108.190748. Epub 2008 Sep 26.
Abstract/Text
PMID 18820172
Baumgartner H, Falk V, Bax JJ, De Bonis M, Hamm C, Holm PJ, Iung B, Lancellotti P, Lansac E, Rodriguez Muñoz D, Rosenhek R, Sjögren J, Tornos Mas P, Vahanian A, Walther T, Wendler O, Windecker S, Zamorano JL; ESC Scientific Document Group.
2017 ESC/EACTS Guidelines for the management of valvular heart disease.
Eur Heart J. 2017 Sep 21;38(36):2739-2791. doi: 10.1093/eurheartj/ehx391.
Abstract/Text
PMID 28886619
薬剤監修について:
オーダー内の薬剤用量は日本医科大学付属病院 薬剤部 部長 伊勢雄也 以下、渡邉裕次、井ノ口岳洋、梅田将光および日本医科大学多摩永山病院 副薬剤部長 林太祐による疑義照会のプロセスを実施、疑義照会の対象については著者の方による再確認を実施しております。
※薬剤中分類、用法、同効薬、診療報酬は、エルゼビアが独自に作成した薬剤情報であり、 著者により作成された情報ではありません。
尚、用法は添付文書より、同効薬は、薬剤師監修のもとで作成しております。
※同効薬・小児・妊娠および授乳中の注意事項等は、海外の情報も掲載しており、日本の医療事情に適応しない場合があります。
※薬剤情報の(適外/適内/⽤量内/⽤量外/㊜)等の表記は、エルゼビアジャパン編集部によって記載日時にレセプトチェックソフトなどで確認し作成しております。ただし、これらの記載は、実際の保険適応の査定において保険適応及び保険適応外と判断されることを保証するものではありません。また、検査薬、輸液、血液製剤、全身麻酔薬、抗癌剤等の薬剤は保険適応の記載の一部を割愛させていただいています。
(詳細はこちらを参照)
著者のCOI(Conflicts of Interest)開示:
中谷 敏 : 報酬額(エドワーズライフサイエンス(株))[2025年]
監修:伊藤浩 : 特に申告事項無し[2025年]

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僧帽弁閉鎖不全症(含む僧帽弁逸脱症)

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