A substudy of BARI, Study of Economics and Quality of Life (SEQOL), was initially funded by the Robert Wood Johnson Foundation to assess the impact of a specific revascularization on quality of life, functional and economic (hospital and physician charges) outcomes in patients randomized to BARI, and to examine factors other than treatments that affect these outcomes. Beginning in July 1997, support for SEQOL was assumed by the NHLBI under grant R01HL58324. The grant, ending in June 2002, extends the follow-up of the randomized SEQOL substudy cohort (752 subjects surviving as of May 1, 1996) to ten years to study the long-term determinants of cost and quality of life and to develop a model to project the impact of technologic changes on outcomes and cost of CABG and PTCA.