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123 Systematic review and meta-analysis comparing bilateral versus single internal thoracic artery grafts in patients with diabetes and obesity undergoing coronary artery bypass graft surgery
  1. Marcus Flather1,
  2. Maria Stefil2,
  3. Mario Gaudino3,
  4. Umberto Benedetto4,
  5. Alastair Gray5,
  6. Stephen Gerry6,
  7. Belinda Lees7,
  8. Lukasz Krzych8,
  9. Siven Seevanayagam9,
  10. David Taggart7
  1. 1University Of East Anglia
  2. 2Norwich Medical School, University of East Anglia, Norwich, UK
  3. 3Weill Cornell Medicine/NewYork-Presbyterian Hospital, New York, USA
  4. 4School of Clinical Sciences, University of Bristol and Bristol Royal Infirmary, Bristol, UK
  5. 5Health Economics Research Centre, University of Oxford, Oxford, UK,
  6. 6Centre for Statistics in Medicine, University of Oxford, Oxford, UK
  7. 7Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
  8. 8Department of Cardiac Surgery, Medical University of Silesia, Katowice, Poland
  9. 9Department of Cardiac Surgery, Austin Health and University of Melbourne, Melbourne, Australia


Background Obesity and diabetes put patients are at higher risk of mortality and other adverse outcomes following coronary artery bypass grafting (CABG) and are becoming more common. The use of bilateral internal thoracic arteries (BITA) can potentially offer survival benefit in higher risk patients compared to single internal thoracic artery (SITA) in patients undergoing CABG. Current evidence does not support the routine use of BITA and this approach is associated with a higher risk of sternal wound complications.

Methods We conducted a systematic review of the literature to identify observational studies and randomised controlled trials (RCT) comparing efficacy (mortality) and safety (sternal wound infection) of BITA and SITA in diabetic and obese patients.

Results Eighteen observational studies and one RCT (subgroup analysis) were identified comparing BITA and SITA in 19,589 patients with diabetes. In contrast there were just two observational studies and one RCT (subgroup analysis) comparing BITA and SITA in 6972 obese patients. Pooled analysis demonstrated significant mortality benefit of BITA compared to SITA in diabetic patients (risk ratio [RR] 0.79; 95% confidence interval [CI] 0.70, 0.90; Z=3.62, p=0.0003; I2=88%) (Figure 1b). Pooled analysis in obese patients found no significant difference in mortality rates between BITA and SITA (RR 0.73, 95% CI 0.47, 1.12; Z=1.43, p=0.15; I2=78%), although the overall effect was for a beneficial trend for BITA (Figure 1a). A significantly higher rate of sternal wound complications following BITA was observed in diabetic (RR 1.53, 95% CI 1.23, 1.90; Z=3.86, p=0.0001; I2=4%) and obese patients (RR 2.24, 95% CI 1.63, 3.07; Z=5.00, p<0.00001; I2=0%).

Abstract 123 Figure 1A Forest plot demonstrating effects of BITA grafting compared to SITA grafting on long-term all-cause mortality in diabetic patients
Abstract 123 Figure 1B Forest plot demonstrating effects of BITA grafting compared to SITA grafting on long-term all-cause mortality in obese patients

Conclusions In a pooled analysis, BITA is associated with better long-term survival in diabetic patients, but most of the supportive data comes from observational studies. The effects of BITA grafting in patients who are obese is uncertain due to low numbers of patients available for analysis. BITA is associated with higher rates of sternal wound complications than SITA in both diabetic and obese patients. Further studies are needed to understand the benefits and risks of multiple arterial grafting in patients with diabetes and/or obesity.

Conflict of Interest None

  • Coronary artery bypass graft
  • diabetes
  • obesity

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