[Re-operative Cardiac Surgery in Patients with Patent In Situ Coronary Artery Bypass Grafts].

Background: Re-operative cardiac surgery after prior coronary artery bypass grafting( CABG), using in situ graft is a challenge. Technical difficulties regarding this procedure include risks of graft injury and myocardial protection. The conventional strategy involves re-sternotomy, dissection, and temporary occlusion of the in situ graft to prevent cardioplegia washout. However, the problem with this procedure is that injury to the in situ graft can result in catastrophic complications.

Methods: We reviewed 25 redo cases of patients who had prior CABG with patent in situ grafts. The in situ grafts were dissected and clamped in 18 (group C) patients, whereas in 7 (group U) patients, the in situ grafts were not dissected or clamped. All patients underwent re-sternotomy, aortic cross clamping and cardiac arrest with cardioplegia. Besides, myocardial protection was obtained using moderate hypothermia and systemic potassium injection in group U.

Results: There were no injuries to the in situ grafts in either group. The peak creatine kinase-MB values were not significantly different between the two groups. Postoperative ejection fraction was preserved in both groups.

Conclusions: The simplified approach of no-clamping technique yielded safety and effectiveness for myocardial protection in redo cases for patients with prior CABG in the presence of patent in situ grafts.