Abstract
Aim: To investigate the relations between myocardial mechanics and the extent of hypertrophy, replacement fibrosis and interstitial fibrosis in hypertrophic cardiomyopathy (HCM), using CMR imaging. Methods: 45 consecutive patients with HCM and 15 control subjects were included. CMR with late gadolinium enhancement (LGE) imaging was performed to evaluate biventricular function, LV mass index and presence/extent of LGE, expression of replacement fibrosis. Myocardial T1 relaxation, a surrogate of interstitial fibrosis, was measured from LookLocker sequence. Feature-tracking analysis was applied to cine images to assess systolic and diastolic global LV circumferential strain (CS) and strain rate (CSr). Results: Peak systolic CS and CSr were significantly higher among HCM patients compared to control subjects (-25±8 vs. -22±3; p=0.015 and -1.66±0.61 vs. -1.33±0.27; p=0.007, respectively). The ratio of peak CSr during early filling to peak systolic CSr was significantly lower among HCM patients (0.88±0.25 vs. 1.11±0.17; p=0.002). At multivariate linear regression analysis, LV mass index (=-0.56; p<0.001) and %LV LGE (=0.33; p=0.005) were significantly and independently related to peak systolic CS; LV mass index (=-0.51; p<0.001) and %LV LGE (=0.30; p=0.023) were significantly and independently related to peak systolic CSr; %LV LGE (=0.31; p=0.021) and T1 ratio (=-0.37; p=0.006) were significantly and independently related to the ratio of peak CSr during early filling to peak systolic CSr. Conclusions: LV systolic mechanics are enhanced and LV diastolic mechanics are impaired in HCM. Hypertrophy and replacement fibrosis influences LV systolic mechanics while replacement and interstitial fibrosis influence LV diastolic mechanics
Original language | English |
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Journal | Heart Lung and Circulation |
Volume | 25 |
Issue number | Supplement 2 |
Publication status | Published or Issued - Aug 2016 |
Event | Cardiac Society of Australia and New Zealand ASM 2016 - Adelaide Convention Centre, Adelaide, Australia Duration: 4 Aug 2016 → 7 Aug 2016 |
Keywords
- Cardiac magnetic resonance
- Feature-tracking
- Hypertrophic cardiomyopathy
- Late gadolinium enhancement
- Strain
- T1 measurement
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging
- Cardiology and Cardiovascular Medicine