Occurrence and risk factors for reintervention after coronary artery bypass grafting.

BACKGROUND: Reintervention after coronary artery bypass grafting (CABG) is common. We sought to determine its occurrence and identify patient characteristics and operative techniques that influence the need or bias for reintervention. METHODS AND
RESULTS: From 1971 to 1998, 48,758 patients underwent primary isolated CABG, and 1000 patients per year were actively followed-up every 5 years (n =26,927). A multivariable time-related analysis was performed to model freedom from first coronary reintervention (either reoperation or percutaneous coronary intervention) and identify patient and operative characteristics associated with first reintervention. A total of 3997 patients underwent coronary reintervention, percutaneous in 1638 and reoperation in 2359. Freedom from reintervention was 99%, 96%, 88%, 73%, 60%, and 46% at 1, 5, 10, 15, 20, and 25 years, respectively. Risk of reintervention (hazard function) demonstrated a short, rapidly declining early phase followed by a longer, slow-rising late phase. Patient variables increasing the likelihood of coronary reintervention included younger age (P<0.0001), higher triglycerides (P=0.002), lower high-density lipoprotein (P=0.006), diabetes mellitus (P<0.0001), and more extensive coronary artery disease (P=0.0005). Increasing extent of arterial grafting performed at primary operation decreased the likelihood of coronary reintervention (P<0.0001).
CONCLUSIONS: Reintervention after primary CABG is common. Risk factors for arteriosclerosis and type of bypass conduit influence the need or bias for repeat coronary therapy. Aggressive post-CABG risk factor reduction and extensive arterial grafting at primary operation should decrease coronary reinterventions.