Mechanical effects of left ventricular midwall fibrosis in non-ischemic cardiomyopathy
Research output: Contribution to journal › Article › peer-review
- University of Birmingham
- The Christ Hospital Heart and Vascular Center, Cincinnati, OH, USA. firstname.lastname@example.org.
- Bakken Research Centre, Medtronic Inc, Maastricht, The Netherlands. email@example.com.
- Queen Elizabeth Hospital
BACKGROUND: Left ventricular (LV) mid-wall fibrosis (MWF), which occurs in about a quarter of patients with non-ischemic cardiomyopathy (NICM), is associated with high risk of pump failure. The mid LV wall is the site of circumferential myocardial fibers. We sought to determine the effect of MWF on LV myocardial mechanics.
METHODS: Patients with NICM (n = 116; age: 62.8 ± 13.2 years; 67% male) underwent late gadolinium enhancement cardiovascular magnetic resonance (CMR) and were categorized according to the presence (+) or absence (-) of MWF. Feature tracking (FT) CMR was used to assess myocardial deformation.
RESULTS: Despite a similar LVEF (24.3 vs. 27.5%, p = 0.20), patients with MWF (32 [24%]) had lower global circumferential strain (Ɛcc: -6.6% vs. -9.4 %, P = 0.004), but similar longitudinal (Ɛll: -7.6 % vs. -9.4 %, p = 0.053) and radial (Ɛrr: 14.6% vs. 17.8% p = 0.18) strain. Compared with - MWF, + MWF was associated with reduced LV systolic, circumferential strain rate (-0.38 ± 0.1 vs. -0.56 ± 0.3 s(-1), p = 0.005) and peak LV twist (4.65 vs. 6.31°, p = 0.004), as well as rigid LV body rotation (64 % vs. 28 %, P <0.001). In addition, +MWF was associated with reduced LV diastolic strain rates (DSRcc: 0.34 vs. 0.46 s(-1); DSRll: 0.38 vs. 0.50s(-1); DSRrr: -0.55 vs. -0.75 s(-1); all p <0.05).
CONCLUSIONS: MWF is associated with reduced LV global circumferential strain, strain rate and torsion. In addition, MWF is associated with rigid LV body rotation and reduced diastolic strain rates. These systolic and diastolic disturbances may be related to the increased risk of pump failure observed in patients with NICM and MWF.
|Journal||Journal of Cardiovascular Magnetic Resonance|
|Publication status||Published - 5 Jan 2016|
- Aged, Biomechanical Phenomena, Cardiomyopathies, Contrast Media, Diastole, England, Female, Fibrosis, Gadolinium DTPA, Heart Failure, Heart Ventricles, Humans, Magnetic Resonance Imaging, Cine, Male, Middle Aged, Myocardium, Predictive Value of Tests, Stress, Mechanical, Systole, Torsion, Mechanical, Ventricular Function, Left, Journal Article, Multicenter Study, Research Support, Non-U.S. Gov't