TY - JOUR
T1 - Topographic mapping of left ventricular regional contractile injury in ischemic mitral regurgitation
AU - Lancaster, Timothy S.
AU - Kar, Julia
AU - Cupps, Brian P.
AU - Henn, Matthew C.
AU - Kulshrestha, Kevin
AU - Koerner, Danielle J.
AU - Pasque, Michael K.
N1 - Funding Information:
Supported in part by funding from the National Institutes of Health grants HL064869, HL069967, HL112804, and T32 HL007776.
Publisher Copyright:
© 2016 The American Association for Thoracic Surgery
PY - 2017/7
Y1 - 2017/7
N2 - Objective Restrictive leaflet tethering resulting from regional left ventricular (LV) contractile injury causes ischemic mitral regurgitation (MR). We hypothesized that 3-dimensional LV topographic mapping by MRI-based multiparametric strain analysis could characterize the regional contractile injury patterns that differentiate ischemic coronary artery disease patients who have ischemic MR from those who do not. Methods Magnetic resonance imaging-based multiparametric strain data were calculated for 15,300 LV grid points in 100 normal volunteers. Strain parameters from ischemic MR (n = 10) and ischemic no-MR (n = 36) patients were then normalized to this normal human strain database with z score quantification of standard deviation from the normal mean. Mean multiparametric strain z scores were calculated for 18 LV subregions (basilar/mid/apical levels; 6 LV regions). Mean strain z scores for papillary muscle-related (basilar/mid levels of anterolateral, posterolateral, and posterior) and nonpapillary muscle-related (all other) subregions were compared between ischemic MR and ischemic no-MR groups. Results Across all patients, contractile injury was greater in the papillary muscle-related regions compared with the nonpapillary regions (P =.007). In the papillary regions, contractile injury was greater in the ischemic MR group compared with the no-MR group (z scores, 1.91 ± 1.13 vs 1.20 ± 1.01, respectively; P <.001). Strain values in the nonpapillary muscle-related subregions were not different between the 2 groups (1.31 ± 1.04 vs 1.20 ± 1.03; P =.301). Conclusions Multiparametric strain analysis demonstrated severe normalized contractile injury in the papillary muscle-related LV subregions in patients with ischemic MR. The mean degree of normalized injury approached 2 standard deviations and was significantly worse than the levels seen in ischemic no-MR patients.
AB - Objective Restrictive leaflet tethering resulting from regional left ventricular (LV) contractile injury causes ischemic mitral regurgitation (MR). We hypothesized that 3-dimensional LV topographic mapping by MRI-based multiparametric strain analysis could characterize the regional contractile injury patterns that differentiate ischemic coronary artery disease patients who have ischemic MR from those who do not. Methods Magnetic resonance imaging-based multiparametric strain data were calculated for 15,300 LV grid points in 100 normal volunteers. Strain parameters from ischemic MR (n = 10) and ischemic no-MR (n = 36) patients were then normalized to this normal human strain database with z score quantification of standard deviation from the normal mean. Mean multiparametric strain z scores were calculated for 18 LV subregions (basilar/mid/apical levels; 6 LV regions). Mean strain z scores for papillary muscle-related (basilar/mid levels of anterolateral, posterolateral, and posterior) and nonpapillary muscle-related (all other) subregions were compared between ischemic MR and ischemic no-MR groups. Results Across all patients, contractile injury was greater in the papillary muscle-related regions compared with the nonpapillary regions (P =.007). In the papillary regions, contractile injury was greater in the ischemic MR group compared with the no-MR group (z scores, 1.91 ± 1.13 vs 1.20 ± 1.01, respectively; P <.001). Strain values in the nonpapillary muscle-related subregions were not different between the 2 groups (1.31 ± 1.04 vs 1.20 ± 1.03; P =.301). Conclusions Multiparametric strain analysis demonstrated severe normalized contractile injury in the papillary muscle-related LV subregions in patients with ischemic MR. The mean degree of normalized injury approached 2 standard deviations and was significantly worse than the levels seen in ischemic no-MR patients.
KW - ischemic mitral regurgitation
KW - myocardial mechanics
KW - regional contractile injury
KW - strain mapping
UR - http://www.scopus.com/inward/record.url?scp=85009815596&partnerID=8YFLogxK
U2 - 10.1016/j.jtcvs.2016.11.055
DO - 10.1016/j.jtcvs.2016.11.055
M3 - Article
C2 - 28109612
AN - SCOPUS:85009815596
SN - 0022-5223
VL - 154
SP - 149-158.e1
JO - Journal of Thoracic and Cardiovascular Surgery
JF - Journal of Thoracic and Cardiovascular Surgery
IS - 1
ER -