Ischemic mitral regurgitation (IMR) affects 1.6 to 2.8 million Americans and increases mortality even when mild. There is a strong graded relationship between the severity of IMR and reduced survival. Valve incompetence in IMR occurs due to a variable combination of leaflet tethering and annular dilation. Mitral valve (MV) repair with undersized annuloplasty rings has become the preferred treatment;however, while annuloplasty effectively addresses annular dilatation, it does not improve and may exacerbate leaflet tethering. MV repair is associated with a 30% recurrence rate of significant IMR (e2+) within 6 months after surgery. This high recurrence rate significantly limits the efficacy of MV repair for IMR. It is likely that a standardized and reliably efficacious surgical therapeutic approach to IMR will not be achievable until the confounding phenomena of recurrent mitral regurgitation can be better understood and subsequently neutralized. A patient-specific approach to treatment, guided by preoperative imaging-based risk stratification for recurrent IMR, is apt to be the best means for achieving this important goal. It is the intent of the proposed project to develop such a tool for risk stratification. The central hypothesis of this proposal is that the degree of pre-repair mitral leaflet tethering determines the degree of recurrent mitral regurgitation after ring annuloplasty for IMR. We further hypothesize that leaflet tethering can be effectively quantified preoperatively by echocardiography and that three-dimensional echocardiography (3DE) is superior to standard two-dimensional echocardiography (2DE) for predicting the degree of recurrent IMR. The proposed study seeks to develop echocardiographic techniques to predict, preoperatively, the degree of recurrent IMR that can be expected for an individual patient within the first year after surgery. The anticipated results of the proposed study will allow surgeons to determine which IMR patients are best treated with standard MV repair (i.e. ring annuloplasty) and which are better served by valve replacement. Such an approach will limit recurrent IMR and simultaneously maximize the number of patients who realize the benefits of MV repair. Both results will improve clinical outcomes. We propose to enroll 378 patients at three high-volume cardiac surgical centers over a 5 year period. Intraoperative 2DE and 3DE parameters will be correlated with the degree of recurrent IMR at 6 and 12 months after surgery.

Public Health Relevance

This study seeks to develop echocardiographic-based analytic tool to predict, preoperatively, the degree of recurrent IMR after mitral valve repair surgery. The results of this study will allow surgeons to identify patients who are likely to fail mitral valve repair and who would be better served by valve replacement. This approach will limit recurrent IMR and simultaneously maximize the number of patients who realize the benefits of mitral valve repair.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL103723-04
Application #
8676903
Study Section
Bioengineering, Technology and Surgical Sciences Study Section (BTSS)
Program Officer
Evans, Frank
Project Start
2011-06-06
Project End
2015-05-31
Budget Start
2014-06-01
Budget End
2015-05-31
Support Year
4
Fiscal Year
2014
Total Cost
Indirect Cost
Name
University of Pennsylvania
Department
Surgery
Type
Schools of Medicine
DUNS #
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Contijoch, Francisco; Witschey, Walter R T; Rogers, Kelly et al. (2016) Impact of end-diastolic and end-systolic phase selection in the volumetric evaluation of cardiac MRI. J Magn Reson Imaging 43:585-93
Bouma, Wobbe; Lai, Eric K; Levack, Melissa M et al. (2016) Preoperative Three-Dimensional Valve Analysis Predicts Recurrent Ischemic Mitral Regurgitation After Mitral Annuloplasty. Ann Thorac Surg 101:567-75; discussion 575
Wijdh-den Hamer, Inez J; Bouma, Wobbe; Lai, Eric K et al. (2016) The value of preoperative 3-dimensional over 2-dimensional valve analysis in predicting recurrent ischemic mitral regurgitation after mitral annuloplasty. J Thorac Cardiovasc Surg 152:847-59
Contijoch, Francisco; Rogers, Kelly; Rears, Hannah et al. (2016) Quantification of Left Ventricular Function With Premature Ventricular Complexes Reveals Variable Hemodynamics. Circ Arrhythm Electrophysiol 9:e003520
Contijoch, Francisco J; Witschey, Walter R T; McGarvey, Jeremy et al. (2016) Slice-by-Slice Pressure-Volume Loop Analysis Demonstrates Native Differences in Regional Cardiac Contractility and Response to Inotropic Agents. Ann Thorac Surg 102:796-802
Lee, Chung-Hao; Carruthers, Christopher A; Ayoub, Salma et al. (2015) Quantification and simulation of layer-specific mitral valve interstitial cells deformation under physiological loading. J Theor Biol 373:26-39
Pouch, Alison M; Tian, Sijie; Takabe, Manabu et al. (2015) Segmentation of the Aortic Valve Apparatus in 3D Echocardiographic Images: Deformable Modeling of a Branching Medial Structure. Stat Atlases Comput Models Heart 8896:196-203
McGarvey, Jeremy R; Kondo, Norihiro; Witschey, Walter R T et al. (2015) Injectable microsphere gel progressively improves global ventricular function, regional contractile strain, and mitral regurgitation after myocardial infarction. Ann Thorac Surg 99:597-603
Contijoch, Francisco; Witschey, Walter R T; Rogers, Kelly et al. (2015) User-initialized active contour segmentation and golden-angle real-time cardiovascular magnetic resonance enable accurate assessment of LV function in patients with sinus rhythm and arrhythmias. J Cardiovasc Magn Reson 17:37
Altmayer, Stephan P L; Teeuwen, Laurens A; Gorman, Robert C et al. (2015) RV mass measurement at end-systole: Improved accuracy, Reproducibility, and reduced segmentation time. J Magn Reson Imaging 42:1291-6

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