Analysis of 14,196 Dutch cardiac bypass patients reveals that choosing between radial artery or right internal thoracic artery as the second arterial graft produces equivalent long-term survival outcomes over a decade of follow-up. However, important sex-specific complications emerged: radial artery grafts increased repeat revascularization rates in men and nearly quadrupled stroke risk in women (0.9% vs 0.2%). Both graft types caused more post-operative arrhythmias when using right thoracic arteries. This registry analysis represents one of the largest comparative studies of multi-arterial grafting strategies, offering crucial real-world evidence for cardiac surgeons. The findings challenge assumptions about optimal graft selection while highlighting previously underappreciated sex differences in surgical outcomes. For patients considering bypass surgery, this suggests graft choice should be individualized based on sex and risk factors rather than following universal protocols. However, as this preprint awaits peer review, these sex-specific risk patterns require validation through additional studies before definitively changing surgical practice guidelines.