Complications of surgery and re-hospitalization Some surgical complications and medical problems have resulted in hospitalization following CABG. In an early study, 23% of CABG patients were re-hospitalized in the first 6 months following surgery. Cardiac problems were responsible for 32% of these hospitalizations, complications of surgery (including cardiac complications) for 14%, gastrointestinal difficulties for 9%, and a wide variety of problems in other organ systems for 45% of hospitalizations (Jenkins et al 1983). More recently, 33% of CABG patients were re-hospitalized in the first 2 years after surgery, with the most common reasons for re-admission being acute myocardial infarction, arrhythmia or angina (Geissler and Aggestrup 2002). Risk factors for re-hospitalization include: length of stay in intensive care; severe non-cardiac complications; duration and severity of pre-operative cardiac symptoms; intra-aortic balloon insertion; pre-operative resting angina; female gender; age; diabetes; and surgical procedure (patients with left internal mammary artery graft or multiple arterial grafts are less likely to be re-hospitalized) (Jenkins et al 1983; Stanton et al 1985; Fasken et al 2001; Damgaard et al 2005). Thus, a significant number of patients are re-hospitalized following CABG, although this high rate of readmission may reflect a greater likelihood that physicians will hospitalize patients if there is a recent history of cardiac surgery. Psychological functioning The reported rates of psychological difficulties following CABG vary widely (Tienari et al 1982; Raja et al 2004). Studies assessing anxiety levels of CABG patients have generally shown that anxiety levels are raised prior to surgery but drop rapidly post-surgery (Jenkins et al 1983; Gardner and Worwood 1997; Boudrez and Backer 2001). One study found that the anxiety of CABG patients pre-operatively was more severe than the reference population of general medical and surgical patients, although anxiety levels significantly improved post-surgery. It has been suggested that such rises in anxiety levels may reflect anticipation of the forthcoming procedure (Jenkins et al 1983). However, some patients appear to suffer severe anxiety for extended periods of time after surgery, which is often associated with substantial depression (Gardner and Worwood 1997). Research indicates that a number of CABG patients are depressed immediately following surgery, with a return to pre- operative levels at discharge. One study found that 50% of patients were significantly depressed 8 days post-surgery, Outcomes of coronary bypass surgery but this declined substantially with time to 24% 8 weeks post- surgery, and 22% at 12 months (Timberlake et al 1997). There are a number of reported reasons for depression following CABG. First, the post-operative period involves substantial discomfort and pain, with patients being isolated from family, friends, and the familiarity of home, which may produce depression (Timberlake et al 1997). Second, pre- operative mood appears to contribute to the prediction of depressive symptoms post-surgery (Jenkins et al 1983; Timberlake et al 1997; Boudrez and Backer 2001). Early studies found that patients with an inability to cope with stressful events, or those with neurotic personality traits, could be identified pre-surgery and were more likely to have poor psychological outcomes following surgery (Magni et al 1987; Timberlake et al 1997). Pre-operative depression scores were shown to account for 34% of the variation in depressed mood post-operatively (Magni et al 1987). More recently, pre- operative levels of depression were shown to be the best predictors of depression at 8 days, 8 weeks and 12 months post-surgery (Timberlake et al 1997). These results emphasize the value of examining patients’ levels of anxiety and depression prior to surgery. Third, there is increasing recognition that CABG may be a risk factor for subtle cognitive decline or psychological abnormalities (Raja et al 2004; Phillips- Bute et al 2006). Neurological complications following CABG include: stroke (5%–6% of patients); and ophthalmologic abnormalities such as retinal infarction, retinal embolization and reduction in visual acuity (13%– 29% of patients) (Van Dijk et al 2002). Cognitive decline may present as short-term memory loss, psychomotor slowing, or executive dysfunction. Proposed mechanisms include surgical-related trauma, microembolization, genetic susceptibility (eg, apolipoprotein E4 allele), other vascular or ischemic changes, and temperature during surgery. Thus the etiology for cognitive decline is most likely multifactorial and includes a synergistic effect of microemboli, hypo-perfusion, and other variables associated with major surgery. Non-pharmacologic (eg, emboli reduction, temperature, or glucose management) and strategies to prevent post-CABG cognitive deficits are currently under investigation (Raja et al 2004). Therefore, studies have shown that a significant proportion of CABG patients experience psychological difficulties post surgery, and there appears to be a range of possible reasons for these difficulties. Vascular Health and Risk Management 2006:2(4) 481