RESUMO
INTRODUCTION: Serum gamma-glutamyl transferase activity (GGT) seems to predict cardiovascular events in different populations. However, no data exist on patients with congenital heart disease (CHD). METHODS: Observational, analytic, prospective cohort study design involving CHD patients and a control population to determine the effect of GGT levels on survival. RESULTS: A total of 589 CHD patients (58% males, 29 ± 14 years old) and 2745 matched control patients were followed up. A total of 69 (12%) CHD patients had a major acute cardiovascular event (MACE) during the follow-up time (6.1 [0.7-10.4] years). Patients with CHD and a GGT >60 U/L were significantly older, more hypertensive and dyslipidemic, had a worse NYHA functional class and a greater anatomical complexity than CHD patients with a GGT ≤60 U/L. The binary logistic regression analysis showed that age, a great CHD anatomical complexity, and having atrial fibrillation/flutter were the predictive factors of higher GGT levels (>60 U/L). The Kaplan-Meier analysis showed that patients with CHD and a GGT concentration above 60 UL showed the lowest probability of survival compared to that of CHD with GGT ≤60 U/L and controls irrespective of their GGT concentrations (p < .001). Similarly, the multivariable Cox regression analysis found an independent association between higher GGT levels (>60 U/L) and a worse prognosis (HR 2.44 [1.34-4.44], p = .003) among patients with CHD. CONCLUSION: Patients with CHD showed significant higher GGT levels than patients in the control group having those with higher GGT concentrations (>60 U/L) the worst survival.