Background: The natural history of coronary artery disease (CAD) after vascular surgery is poorly defined. The aim of this study was to determine the temporal change of coronary artery lesions requiring revascularization with a percutaneous coronary intervention (PCI) after elective vascular surgery and to determine the utility of preoperative biomarkers on predicting those patients at risk for new coronary lesions. Methods: The Coronary Artery Revascularization Prophylaxis Trial tested the long-term survival benefit of coronary artery revascularization before elective vascular surgery. Among randomized patients who subsequently required PCI after surgery, the stenosis of the culprit lesion from the follow-up angiogram was compared with the preoperative vessel stenosis at the identical site on the baseline angiogram. Results: A total of 30 patients underwent PCI for progressive symptoms at a median of 11.5 (interquartiles: 4.5-18.5) months postsurgery. Of 30 patients, 16 (53%) had nonobstructive CAD preoperatively (group 1) with a stenosis that increased from 17 ± 6% to 91 ± 2% (P < 0.01) and 14 (47%) had severe CAD at the culprit site preoperatively (group 2), with a stenosis that increased 89 ± 2% (P = 0.15). The only biomarker that was an identifier of early coronary artery lesion formation in group 1 compared with group 2 patients was a higher baseline homocysteine level (14.6 ± 1.4 vs. 10.6 ± 0.7 mg/dL; P = 0.02). Conclusions: Culprit coronary artery lesions requiring PCI after an elective vascular operation often arise from in-stent restenosis. Therapies that either stabilize existing plaques or prevent restenosis, particularly among patients with elevated homocysteine levels, have the greatest promise for improving postoperative outcomes.