Objective To estimate the heritability of myocardial blood flow (MBF) and coronary flow reserve (CFR) measured with positron emission tomography (PET).
Design Cross-sectional twin study.
Setting General clinical research centre of a university hospital at Atlanta, USA.
Patients A sample of 180 middle-aged (mean±SD 55±2.9 years) male twins, including 107 monozygotic and 73 dizygotic twins.
Main outcome measures All twins underwent imaging of MBF with PET 13NH3 at rest and after adenosine stress during a single imaging session. Structural equation modelling was used to estimate the heritability of MBF at rest and during adenosine stress, as well as of CFR.
Results The basal MBF (mean±SD) was 0.69±0.20 ml/min/g, and the MBF during adenosine stress was 1.70±0.49 ml/min/g; the CFR was 2.62±0.99. There was substantial heritability for MBF both at rest (0.48, 95% CI 0.29 to 0.64) and during adenosine stress (0.51, 95% CI 0.29 to 0.68), as well as CFR (0.48, 95% CI 0.26 to 0.65).
Conclusions For the first time, a substantial genetic contribution to the interindividual variation in MBF and CFR measured with PET in middle-aged men has been demonstrated. The data suggest that a fruitful direction for future work would be the identification of genetic variants for early atherosclerotic stages assessed by PET imaging.
- Coronary flow reserve
- myocardial blood flow
- positron emission tomography
- twin study
Statistics from Altmetric.com
Funding This study was supported by K24HL077506, R01 HL68630 and R01 AG026255 from the National Institutes of Health, and by grants 0245115N, 0725513B and 09SDG2140117 from the American Heart Association and MO1-RR00039 from the Emory University General Clinical Research Center. The funding sources had no involvement in the design, analysis and interpretation of the data presented in this paper.
Competing interests None.
Patient consent Obtained.
Ethics approval This study was conducted with the approval of the institutional review board at Emory University.
Provenance and peer review Not commissioned; externally peer reviewed.