Symptomatic graft failure and impact on clinical outcome after coronary artery bypass grafting surgery: Results from the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease registry.

BACKGROUND: In contemporary coronary artery bypass graft (CABG) surgery, the association between symptomatic graft failure (GF) and long-term clinical outcome remains unclear. We sought to identify the clinical characteristics and outcomes of GF in symptomatic patients requiring cardiac catheterization within 1 year of CABG surgery.

METHODS: Using the Alberta Provincial Project for Outcomes Assessment in Coronary Heart Disease registry, 5,276 patients undergoing CABG surgery from September 2002 to August 2011 were identified. Clinical outcomes in patients with symptomatic GF were observed. Predictors of GF were analyzed at a graft level, whereas long-term survival was assessed at a patient level. A propensity score matching technique was used to adjust for baseline characteristics.

RESULTS: Of our CABG cohort, 5.3% (281 patients [285 arterial and 653 vein grafts]) required symptom based coronary angiography within 1 year of CABG surgery. Acute coronary syndrome was the most common presentation (64.4%). At angiography, 27.0% (77/285) of arterial and 34.5% (225/653) of vein grafts were occluded. Respectively, arterial and vein GFs were treated as follows: percutaneous coronary intervention 61.0% versus 41.8%, re-do CABG 9.1% versus 0%, and medically without intervention 29.9% versus 58.2%. A strong trend toward reduced patient survival was noted with "arterial graft failure" (arterial ± vein GF) compared to "vein graft failure only" (no arterial GF) (adjusted hazard ratio 2.2, 95% CI 0.98-5.0, P = .056).

CONCLUSION: Although the rate of cardiac catheterization within 1 year of CABG is infrequent, these patients exhibit high GF rates and commonly present with an acute coronary syndrome. In addition, "arterial graft failure" compared to "vein graft failure only" confers a higher risk of adverse long-term survival.