Follow-up arteriograms carried out between one and six years (mean follow-up period two years) in 80 cases of aorto-coronary bypass graft procedures showed a good correlation between the quality of the clinical results obtained -- as detailed in the first part of this article -- and a larger proportion of patent grafts: 82% of 130 grafts had remained patent, and 94% of patients have all or some of their grafts patent. Late occlusion of the grafts is rare, and does not appear to be influenced by abnormalities of the graft found at early follow-up, these abnormalities being fairly stable. These follow-up have especially shown the good correlation between the quality of the clinical results and the functional status of the coronary network in the long term, a function not only of the permeability of the grafts which have been carried out, but also of the complete or incomplete correction of the lesions of the three coronary trunks. Such a complete procedure which was carried out or could have been carried out in only 30% of the total patients, was then successful in 94% undergoing it. The clinical results should therefore lead us to carry out operations which remove the lesions as completely as possible.