Subvalvular Papillary Muscles Displacement/Dysfunction in Patients with Late Systolic Mitral Valve Prolapse

• Project/Area Number: 24500562
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Medical systems
• Research Institution: University of Occupational and Environmental Health, Japan
• Principal Investigator: OTSUJI Yutaka 産業医科大学, 医学部, 教授 (30264427)
• Co-Investigator(Kenkyū-buntansha): TAKEUCHI Masaaki 産業医科大学, 医学部, 准教授 (30236434) ; YOSHITANI Hidetoshi 産業医科大学, 医学部, 助教 (30351894) ; HARUKI Nobuhiko 産業医科大学, 医学部, 助教 (70469394) ; KUWAKI Hiroshi 産業医科大学, 医学部, 修練指導医 (80623868) ; FUKUDA Shota 産業医科大学, 医学部, 助教 (00464610)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000); Fiscal Year 2014: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2013: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2012: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000)
• Keywords: mitral valve / papillary muscle / echocardiography / mitral valve prolapse / 心エコー図 / 僧帽弁逸脱

Outline of Final Research Achievements

Background： We hypothesized that impaired subvalvular geometric stability with papillary muscles (PMs) displacement and/or dysfunction is associated with late-systolic mitral valve prolapse (MVP).
Methods and results：In 15 controls, 10 patients with holo-systolic MVP, and 14 with late-systolic MVP, 1) distances between papillary muscles (PMs) base, PMs tip, and MV annulus and 2) MV coaptation height from its annulus were measured by echocardiography speckle tracking analysis. By multivariate analysis, systolic shift of MV coaptation toward LA was significantly correlated with systolic shift of PMs tip toward LA (r=0.80, p<0.0001), and systolic shift of PMs tip was significantly correlated with both systolic shift of PMs base toward LA (r=0.69, p<0.0001) and reduced PMs contraction(r=0.52, p=0.0007).
Conclusion：Late systolic MVP was associated with impaired stability in subvalvular geometry, including systolic shift of PMs toward LA and impaired PMs contraction.

Research Products

• [Journal Article] The unsaddled annulus biomechanical culprit in mitral vavle prolapse. (2013)
  • Author(s): Morten OJ, Hagege AA, Otsuji Y, Levine RA.
  • Journal Title: Circulation Volume: 127 Pages: 766-768
  • Peer Reviewed
• [Presentation] Echocardiography is an Adventure of Looking and Thinking (2015)
  • Author(s): 尾辻 豊
  • Organizer: 第26回日本心エコー図学会学術集会
  • Place of Presentation: 北九州国際会議場（福岡県北九州市）
  • Year and Date: 2015-03-27
  • Invited
• [Presentation] Insufficient Papillary Muscle Contraction is Involved in Late Systolic Mitral Valve Prolapse: Quantitative Echocardiographic Study with Speckle Tracking Analysis (2012)
  • Author(s): 桑木 恒、竹内正明、ＪＹ Ｊａｎｇ、ＢＪ Ｓｕｎ，岩瀧麻衣、大谷恭子、舩津順子、春木伸彦、芳谷英俊、ＪＫ Ｓｏｎｇ，ＲＡ Ｌｅｖｉｎｅ、尾辻 豊
  • Organizer: American Heart Association 2012
  • Place of Presentation: Down Town Convention Center(Los Angeles, USA)