Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5966049 | International Journal of Cardiology | 2015 | 7 Pages |
ObjectivePatients with repaired tetralogy of Fallot (ToF) have an increased long-term risk of cardiovascular morbidity and mortality. Risk stratification in this population is difficult. Initial evidence suggests that cardiopulmonary exercise testing (CPET) may be helpful to risk-stratify patients with repaired ToF.Methods and resultsWe studied 875 patients after surgical repair for ToF (358 females, age 25.5 ± 11.7 year, range 7-75 years) who underwent CPET between 1999 and 2009. During a mean follow-up of 4.1 ± 2.6 years after CPET, 30 patients (3.4%) died or had sustained ventricular tachycardia (VT). 225 patients (25.7%) had other cardiac related events (emergency admission, surgery, or catheter interventions). On multivariable Cox regression-analysis, %predicted peak oxygen uptake (VËO2 %) (p = 0.001), resting QRS duration (p = 0.030) and age (p < 0.001) emerged as independent predictors of mortality or sustained VT. Patients with a peak VËO2 â¤Â 65% of predicted and a resting QRS duration â¥Â 170 ms had a 11.4-fold risk of death or sustained VT.Ventilatory efficiency expressed as VËE/VËCO2 slope (p < 0.001), peak VËO2 % (p = .001), QRS duration (p = .001) and age (p = 0.046) independently predicted event free survival. VËE/VËCO2 slope â¥Â 31.0, peak VËO2 % â¤Â 65% and QRS duration â¥Â 170 ms were the cut-off points with best sensitivity and specificity to detect an unfavorable outcome.ConclusionsCPET is an important predictive tool that may assist in the risk stratification of patients with ToF. Subjects with a poor exercise capacity in addition to a prolonged QRS duration have a substantially increased risk for death or sustained ventricular tachycardia, as well as for cardiac-related hospitalizations.