In a recent paper [Carbon 127, 64 (2018)], Marta Saiz-Bretín et al. use non-equilibrium molecular dynamics to investigate the heat current due to the atomic lattice vibrations in graphene nanoribbons and nanorings under a thermal gradient. They consider a wide range of temperature, nanoribbon widths up to 6nm and the effect of moderate edge disorder. They find that narrow graphene nanorings can efficiently suppress lattice thermal conductivity at low temperatures (~100K), as compared to nanoribbons of the same width. Remarkably, rough edges do not appear to have a large impact on lattice energy transport through graphene nanorings while nanoribbons seem more affected by imperfections. Furthermore, they demonstrate that the effects of hydrogen-saturated edges can be neglected in these graphene nanostructures.