Coronary artery bypass grafting in young patients - a brazilian retrospective cohort study

ABSTRACT

BACKGROUND: The prevalence of early Coronary Artery Disease (CAD) (i.e., patients under 45 years) is increasing, which entails an equal rise in disability-adjusted life years due to disease burden. Risk factors in this population are not entirely elucidated. Hence, our objectives were to evaluate the clinical characteristics, risk factors, and outcomes in patients under 45 and over 45 years undergoing Coronary Artery Bypass Grafting (CABG). METHODS: We performed a retrospective-comparative cohort between patients under and over 45 years, who underwent CABG at Instituto Dante Pazzanese de Cardiologia, in São Paulo/Brazil, from 1999 to 2015. Patientsʼ characteristics were evaluated by Fisher Exact Test, and risk factors for in-hospital mortality were assessed by Stepwise Logistic Regression. Survival analysis was performed by Kaplan Meier and Log Rank Test. RESULTS: During the study timeframe, 8,889 patients underwent surgery and, out of those, 408 were young. The follow-up period ranged from 10 days to 257 months. Patients under 45 years were associated with higher rates of hypertriglyceridemia, current smoking, previous myocardial infarction and family history of coronary artery disease. Further, they presented higher rates of single vessel disease (11% versus 5.4%, p<0.001), with higher incidence of isolated occlusion of the left anterior descending artery (10.8% versus 5.1%, p<0.001). The younger group had a higher number of coronary artery bypass grafts (2.75±0.82 versus 2.6±0.88, p<0.001). Finally, they were also associated with lower in-hospital mortality (1.7% versus 5.1%, p=0.001). Survival estimates in 10 and 15 years among patients under 45 years were 91.7% and 87.7%, respectively, with an average lifespan of 237,21 months. CONCLUSION: Although hypertriglyceridemia, smoking and family history are well-recognized risk factors for CAD, they may play a more significant role in younger patients. Additionally, this study showed that CAD has a different clinical course in patients under 45 years, which urges the need to readdress how these patients are screened, evaluated and treated. To our knowledge, this is the first Brazilian study to assess this special population.