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We appreciate the thoughtful response of Dr Odell [1Odell J.A. Coronary artery bypass grafting after previous stenting is associated with compromised long-term efficacy (letter).Ann Thorac Surg. 2008; 86: 1052Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar] to our article [2Rao C. Stanbridge R.L. Chikwe J. et al.Does previous percutaneous coronary stenting compromise the long-term efficacy of subsequent coronary artery bypass surgery? A microsimulation study.Ann Thorac Surg. 2008; 85: 501-507Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar]. Odell highlights a case report [3Tovar E.A. Blau N. Borsari A. Landa D.W. Packer J.M. Severe deformity of a Palmaz-Schatz stent after normal surgical manipulation.Ann Thorac Surg. 1997; 63: 220-221Abstract Full Text Full Text PDF PubMed Scopus (7) Google Scholar] and an animal study [4Tovar E.A. Borsari A. Effects of surgical manipulation on coronary stents: should surgical strategy be altered?.Ann Thorac Surg. 1997; 63: 37-40Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar], suggesting that deformation of intracoronary stents may occur intraoperatively from routine manipulation of the heart. Although neither study was identified by our review of the literature, this putative mechanism fits well within the paradigm we propose to explain the increased mortality and morbidity observed in patients with prior intracoronary stents who subsequently undergo elective coronary artery bypass grafting [5Thielmann M. Leyh R. Massoudy P. et al.Prognostic significance of multiple previous percutaneous coronary interventions in patients undergoing elective coronary artery bypass surgery.Circulation. 2006; 114: I441-I447PubMed Google Scholar, 6Thielmann M. Neuhauser M. Knipp S. et al.Prognostic impact of previous percutaneous coronary intervention in patients with diabetes mellitus and triple-vessel disease undergoing coronary artery bypass surgery.J Thorac Cardiovasc Surg. 2007; 134: 470-476Abstract Full Text Full Text PDF PubMed Scopus (48) Google Scholar]. Within this paradigm, we divide the possible mechanisms into three types (Table 1). First, intrinsic pathophysiology consists of the factors that predispose patients to coronary artery bypass surgery after previous stenting. Second, acquired pathophysiology represents the direct results of prior coronary artery stenting. Finally, we list potential technical sequelae resulting from previous coronary stents. It is not possible from available data to determine which of these mechanisms are primarily responsible for the adverse outcomes we have outlined. Therefore, we have designed a prospective exploratory study (ie, the Surgery After Stenting [SAS] trial) to specifically identify the dominant processes to better inform selection of initial revascularization strategy in patients that are likely to need eventual coronary artery bypass surgery.Table 1Proposed Mechanisms of Adverse Outcomes After Elective Coronary Artery Bypass Surgery in Patients With Prior Intracoronary StentsClassificationVariableIntrinsic pathophysiologyMore aggressive coronary artery diseaseGreater age and comorbidityAcquired pathophysiologyPeri-procedural infarctionLocal inflammatory responseProlonged endothelial dysfunctionα-adrenergic upregulationCoagulopathy from adjunctive anti-platelet therapyPostoperative acute stent thrombosisTechnical sequelaeGrafting more distallyPoor target quality after “stent-ectomy”Inadvertent compression occlusion of stentsCompetitive flow through patent stents Open table in a new tab Coronary Artery Bypass Grafting After Previous Stenting is Associated With Compromised Long-Term EfficacyThe Annals of Thoracic SurgeryVol. 86Issue 3PreviewThe article by Rao and colleagues [1] is another supporting argument that coronary artery bypass grafting is the better option for management of coronary artery disease. I have a poor understanding of the statistical model myself, but I do understand the hypotheses that have been proposed that may play a role. The authors mention that in-stent stenosis is associated with a higher risk of early venous graft failure: the grafts are performed more distally, the discontinuation of antiplatelet medication may result in an in-stent stenosis, and there may be pathophysiologic changes associated with an intravascular foreign body. Full-Text PDF