REOPERATIVE CORONARY-ARTERY BYPASS-SURGERY - IMPROVED PRESERVATION OFMYOCARDIAL-FUNCTION WITH RETROGRADE CARDIOPLEGIA

Background. Cardiac-related mortality remains high for reoperative cor onary artery bypass graft surgery (rCABG) compared with first-time sur gery (fCABG). Retrograde cardioplegia (RC) has been suggested but not proven to improve the results for rCABG. Methods and Results. We there fore reviewed the records of 240 consecutive patients who had undergon e rCABG at our institution since 1988. The interval to reoperation was 9.1+/-4.2 years (mean+/-SD), with a range from 0.2 to 18 years. Only 46% of grafts were patent at the time of rCABG. The incision to cardio pulmonary bypass (CPB), incision to cross-clamp (XCL), and XCL per gra ft time intervals were significantly prolonged compared with 100 conse cutive fCABG patients operated on during the same time period. Blood u tilization was also significantly increased in rCABG compared with fCA BG patients. Overall operative mortality was 5.8% and 0% for rCABG and fCABG patients, respectively (P<.05). High-risk criteria (emergency s urgery, angina at rest requiring intravenous nitroglycerin or intra-ao rtic balloon pump [IABP] support [urgent surgery], recent [<21 days] m yocardial infarction, or ejection fraction <30%) were noted in 136 rCA BG patients (57%) and 28 fCABG patients (28%) (P<.001). Profound posto perative myocardial dysfunction (postoperative IABP dependence) occurr ed in only one of 104 low-risk patients (1%), compared with 14 of 136 high-risk patients (10%) (P<.005). Operative mortality was noted in 13 high-risk patients (9.5%) compared with one low-risk patient (1%) (P< .005). RC was used in 80 patients without complication. Postoperative IABP dependence developed in only 2 of 53 high-risk/RC patients (3.8%) compared with 12 of 83 high-risk/non-RC patients (14.5%) (P<.05). At follow-up, rCABG and fCABG patients enjoyed similar symptomatic improv ement. Conclusions. We conclude that retrograde cardioplegia, possibly by minimizing the increased ischemia associated with rCABG, improves the results of rCABG, specifically in regard to preventing profound my ocardial dysfunction in high-risk patients.