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Aims The aim of this study was to evaluate the possible value of dobutamine stress cardiac magnetic resonance imaging (CMR) to predict adverse outcome in Tetralogy of Fallot (TOF) patients. Methods and results In previous prospective multicentre studies, TOF patients underwent low-dose dobutamine stress CMR (7.5 µg/kg/min). Subsequently, during regular-care patient follow-up, patients were assessed for reaching the composite endpoint (cardiac death, arrhythmia-related hospitalization, or cardioversion/ablation, VO2 max ≤65% of predicted). A normal stress response was defined as a decrease in end-systolic volume (ESV) and increase in ejection fraction. The relative parameter change during stress was calculated as relative parameter change = [(parameterstress − parameterrest)/parameterrest] * 100. The predictive value of dobutamine stress CMR for the composite endpoint was determined using time-to-event analyses (Kaplan–Meier) and Cox proportional hazard analysis. We studied 100 patients [67 (67%) male, median age at baseline CMR 17.8 years (interquartile range 13.5–34.0), age at TOF repair 0.9 years (0.6–2.1)]. After a median follow-up of 8.6 years (6.7–14.1), 10 patients reached the composite endpoint. An abnormal stress response (30% vs. 4.4%, P  = 0.021) was more frequently observed in composite endpoint patients. Also in endpoint patients, the relative decrease in right ventricular ESV decreased less during stress compared with the patients without an endpoint (−17 ± 15 vs. −26 ± 13 %, P  = 0.045). Multivariable analyses identified an abnormal stress response (hazard ratio 10.4; 95% confidence interval 2.5–43.7; P  = 0.001) as predictor for the composite endpoint. Conclusion An abnormal ventricular response to dobutamine stress is associated with adverse outcome in patients with repaired TOF. [ABSTRACT FROM AUTHOR]

Aims To evaluate the additional value of dobutamine stress testing in patients with repaired tetralogy of Fallot (TOF) by relating stress imaging parameters at baseline to relevant parameters of clinical condition and right ventricular (RV) size during a serial follow-up. Methods and results We prospectively included 27 patients (14 ± 4 years at baseline), who were studied twice with a 5-year interval. Patients underwent cardiovascular magnetic resonance imaging to assess RV systolic and diastolic function at rest and during dobutamine stress. Normal response to dobutamine was defined as a decrease in RV end-systolic volume, and a increase in RV ejection fraction (EF) during stress. Exercise testing and electrocardiography were performed to determine peak oxygen uptake (peak VO2), QRS duration, and QT interval corrected for heart rate (QTc) interval. RV volumes, QRS duration, and QTc interval increased significantly from baseline to follow-up; peak VO2 tended to decrease (95 ± 20–89 ± 14%, P = 0.086). Response to dobutamine was normal in 26 of 27 patients and remained stable during the follow-up [relative increase in RVEF during stress: +25 ± 9% (baseline) vs. +27 ± 10% (follow-up)]. A smaller relative increase in RVEF during stress at baseline related to a larger relative decrease in peak VO2 during the follow-up (r = 0.59, P = 0.004). No significant associations were found with the relative increase in QRS duration, QTc interval, or RV end-diastolic volume during a 5-year follow-up. Conclusion In a young TOF population, response to dobutamine stress was normal and remained stable during the 5-year follow-up. A smaller increase in RVEF during stress at baseline was predictive for a larger decrease in peak VO2 during the 5-year follow-up. [ABSTRACT FROM PUBLISHER]