Predictors of mid-term event-free survival in adults with corrected Tetralogy of Fallot

Background Patients who underwent corrective surgery for Tetralogy of Fallot (TOF) have increased long-term risk of cardiovascular morbidity and mortality. Yet limited information is available on how to evaluate risk in this population. Therefore the aim of this study was to assess the prognostic value of several demographic, clinical and exercise variables in these patients. Methods Between 2000 and 2003, 91 adults (age 26.2 ±7.8 years; 63 male, 28 female) who had corrective surgery for TOF during childhood, underwent a cardiopulmonary exercise test until exhaustion and echocardiography. During a follow-up of 7.3 ± 1.2 years (range 0.9 to 9.3 years), 2 patients died at an age of 17 and 41 years old, and 26 patients required at least 1 cardiac-related intervention (6 balloon dilatation, 7 EPU with ablation, 10 pulmonary valve replacement, 4 ICD-implantation, 1 pacemaker implantation) at a mean age of 28.9 ± 7.9 years. Cox proportional-hazards multiple regression analysis was used to assess the relation between baseline variables and event-free survival. Results At multivariate Cox analysis, NYHA-class (hazard ratio: 24.069, p=0.0006), right ventricular function (hazard ratio: 5.382, p=0.0019), age (hazard ratio: 1.168, p=0.0087), age at correction (hazard ratio: 0.761, p=0.0317), percentage of predicted peak oxygen uptake (peak VO2%) (hazard ratio: 0.945, p=0.0062), oxygen uptake efficiency slope (OUES) (hazard ratio: 1.002, p=0.0010), and ventilatory efficiency-slope (VE/VCO2-slope) (hazard ratio: 1.136, p=0.0476) were significantly related to the incidence of death/cardiac-related intervention during medium follow-up among demographic, clinical, echocardiographic and exercise variables. Conclusions Early corrective surgery and a well preserved right ventricular function as assessed by echocardiography are associated with a better outcome in adults with corrected TOF. Furthermore, cardiopulmonary exercise testing provides important prognostic information; peak VO2%, OUES and VE/VCO2-slope are independent predictors for mortality/need for cardiac-related intervention in patients with corrected Tetralogy of Fallot.status: publishe