Off-pump coronary revascularization of the circumflex system: Comparison between sequential and nonsequential arterial grafts

Background: Sequential grafting increases the availability of arterial grafts. This study aims to determine the safety and efficacy of sequential grafting of the circumflex coronary distribution performed off-pump. Methods: Between 2000 and 2003, 136 patients undergoing off-pump sequential arterial grafting of the circumflex territory were compared to 278 patients who received nonsequential grafts to the same area. Results: The grafts/patient ratio was higher in the sequential than the nonsequential group (3.2 ± .4 and 2.3 ± .2, respectively, P < .0001). Radial artery conduits and T-grafts were used more often in the sequential group; conversely, bilateral internal thoracic artery configurations were more frequent in the nonsequential groups (P < .0001). There were 1.2 sequential anastomoses per patient. Early mortality (2.2% versus 2.5%), myocardial infarction (2.2% versus 1.1%) and stroke (.7% versus none) rates were comparable. Use of sequentials or other operative confounders had no independent effect on the occurrence of early adverse events (stepwise logistic regression). At 3.5 years, survival was 95.9% and 84.2% in the sequential and nonsequential groups, respectively (P = .231, log-rank). Despite comparable incidence of major adverse cardiac events (MACE) (6.6% versus 8.6%, P = .470) and similar 3.5-year freedom from MACE (88.7% for both groups, P = .682), Cox regression analysis identified sequential grafting as an independent predictor of MACE (P < .0001, HR 19.9), increasing this risk by 20-fold. Conclusions: Off-pump sequential grafting of the circumflex system may be safely performed. The use of sequentials, however, had an independent effect on increased mid-term MACE. The distribution of events suggests culpability of surgical factors and may reflect a learning curve.