ORIGINAL ARTICLE
Repeated revascularization in patients with prior coronary bypass grafting: feasibility and outcome

Native vessel (nv) atherosclerosis progression and bypass grafts (bg) degeneration limit the long-term outcome in patients with coronary bypass grafting (CABG).
The study aimed to assess mechanisms of angina recurrence, feasibility and the long-term outcome in patients undergoing percutaneous revascularization (PCI).
Material and methods: We studied 215 consecutive patients (80.9% men, mean age 62.8±8.1 y, range 40-82 y) with angina recurrence 92.9±48.8 months after CABG who underwent repeated coronary angiography. In patients referred for PCI, periprocedural troponin I (TnI) and MB fraction of creatine kinase (CK-MB) were evaluated.
Results: In 186 patients we identified the reason for symptom recurrence: bg insufficiency in 38.6%, nv atherosclerosis progression in 23.3%, and both in 24.7%. PCI was attempted in 123 (66.1%) patients, and 5 (2.7%) were referred for CABG. PCI of bg was performed in 27.6% of patients, nv – in 61.0%, and both nv and bg in 11.4% (mean 1.4 lesions/patient). PCI was successful in 118 (95.9%) patients. During the periprocedural period there was 1 non fatal myocardial infarction (MI), and 1 intracranial hemorrhage following tissue plasminogen activator (tPA) administration. In the long term follow-up (FU) (mean 23.9±10.6 months, range 6–41 months), major cardiac events (MACE) occurred in 35 (29.7%) patients, including 5 (4.2%) deaths, 12 (10.2%) MIs, and 25 (21.2%) re-PCI. MACEs occurred in a higher proportion of patients after bg PCI than nv PCI (59% vs. 38%; p=0.014), and bg or nv PCI in the left anterior descending (LAD) artery territory as compared to other localizations (p=0.05). Both diagnosis of acute coronary syndrome at the time of PCI and postprocedural TnI, CK-MB increase significantly correlated with restenosis and MI in FU.
Conclusions: Bg atherosclerosis is the leading cause of angina recurrence in patients with prior CABG; in 50% of patients there is also nv atherosclerosis progression. PCI is feasible in 2/3 of patients with angina recurrence after CABG. The bg and LAD territory PCI, and periprocedural TnI and CK-MB increase are related to higher cardiac event rate.