Heart failure & cardiomyopathies
Microstructural and Microvascular Phenotype of Sarcomere Mutation Carriers and Overt Hypertrophic Cardiomyopathy
Authors' conclusion
Microstructural alteration and MVD occur in overt HCM and are different in G+ and G- patients. Both also occur in the absence of hypertrophy in sarcomeric mutation carriers, in whom changes are associated with electrocardiographic abnormalities.
Study context
- Population
- Sarcomere mutation carriers and patients with overt hypertrophic cardiomyopathy (HCM), assessed by 12-lead ECG, quantitative perfusion CMR and cardiac diffusion tensor imaging101 with overt HCM
- Participants
- 206 carriers
- Exposure
- Overt HCM and subclinical HCM vs matched healthy volunteers
- G+LVH+n = 51
- G-LVH+n = 50
- G+LVH-n = 77
- Healthy volunteersn = 28reference
- Outcome
- Myocardial microstructure (diffusion tensor imaging) and MVD (perfusion CMR)
Methodological detailsmulticentre
- Multicentre
Main finding
As reported in the abstract
- Overt HCM vs healthy volunteers: lower fractional anisotropy, higher mean diffusivity and higher second eigenvector angle
- all P<0.001
- Overt HCM vs healthy volunteers: lower stress myocardial blood flow and myocardial perfusion reserve
- both P<0.001
- G-LVH+ similar to G+LVH+ but elevated second eigenvector angle (adjusted for LV hypertrophy and fibrosis)
- P<0.001
- G+LVH- vs healthy volunteers: altered microstructure, to a lesser extent (all diffusion tensor imaging parameters)
- P<0.001
- G+LVH- vs healthy volunteers: reduced stress myocardial blood flow
- P=0.015
Observational data: associations, not effects.
Further findings
| Outcome | G+LVH+ | G-LVH+ | G+LVH- | Healthy volunteers | OR | P value | |
|---|---|---|---|---|---|---|---|
| Perfusion defects in overt HCM, G+ vs G- | P = 0.001 | ||||||
| Microstructure and MVD, G+LVH- vs healthy volunteersPerfusion defects | Not reported in the abstract | Not reported in the abstract | 28% | 0 events | P = 0.002 | G+LVH+, G-LVH+: not reported in the abstract | |
| Microstructure and MVD, G+LVH- vs healthy volunteersReduced stress myocardial blood flow | P = 0.015 | ||||||
| Association with abnormal ECGSubclinical · fractional anisotropy · adjusted for fibrosis and LV hypertrophy | 4.0 | P = 0.001 | |||||
| Association with abnormal ECGSubclinical · myocardial perfusion reserve · adjusted for fibrosis and LV hypertrophy | 2.2 | P = 0.049 |
- Microstructure and microvascular disease (MVD), G+LVH- vs healthy volunteers — Altered microstructure, to a lesser extent (all diffusion tensor imaging parameters)
- P<0.001
- Perfusion defects in overt HCM, G+ vs G-: G+ 100%
- Perfusion defects in overt HCM, G+ vs G-: G- 82%
Microstructure, G-LVH+ vs G+LVH+
- G-LVH+ similar to G+LVH+ but with elevated second eigenvector angle
- P < 0.001
- After adjustment for LV hypertrophy and fibrosis
Parts of this Brief are withheld: the automatic checks could not confirm them against the abstract.
Original publication
Microstructural and Microvascular Phenotype of Sarcomere Mutation Carriers and Overt Hypertrophic Cardiomyopathy. Circulation. Published 18 July 2023. doi:10.
Summarised from the published abstract; every number is checked against it