Oral Abstract session: Advanced echo techniques - New eyes on congenital heart disease: Thursday 4 December 2014, 08:30-10:00 * Location: Agora

Background: Adults with repaired tetralogy of Fallot (rTOF) are at increased risk for arrhythmic events. Objectives: To evaluate whether right ventricle (RV) and right atrial (RA) two-dimensional speckle tracking (2D strain) are associated with arrhythmic events in patients with rTOF. Methods: We studied 65 consecutive patients with rTOF (34 ± 10 years, 71% males) referred for routine echocardiographic evaluation. We obtained standard echocardiographic measurements that included right heart assessment: RV end-diastolic and systolic area (RVESA), RV fractional area change (RVFAC), tricuspide annular plane systolic excursion (TAPSE), Tei Index, tissue Doppler of the tricuspid ring, tricuspide and pulmonary valve evaluation, residual defects. RV and RA 2D strain was assessed in a 4-chamber view. Patients were divided into two groups: Group 1 (with previous documentation of arrhythmias) and Group 2 (without arrhythmias). Logistic regression analysis was used to assess the statistical association between the studied parameters and arrhythmic events. Results: There were 14 patients with arrhythmic events (8 supraventricular, 4 ventricular and 2 with both). Patients in Group 1 were older (44 ± 11 vs. 32 ± 9 years, p<0.001), had surgical repair at an older age (16 ± 13 vs. 9 ± 11 years, p=0.019) and had the echo examination later after repair (28 ± 11 vs. 23 ± 6 years, p=0.025). All the other measurements were similar between groups. RV strain correlated with all RV function parameters (RVFAC: r= - 0.35; RVESV: r=0.36; TAPSE: r= - 0.36; tricuspide S': r= - 0.30) and with RA strain (r= - 0.51). RA strain correlated also with tricuspide A' (r=0.31) and TAPSE (r=0.27). Patients in Group 1 had significantly reduced RV strain (-13.0 ± 6.3 vs. -16.9 ± 3.6%, p=0.043) and RA strain (33.0 ± 7.2 vs. 28.5 ± 9.2%, p=0.027). RV strain is an independent predictor for the presence of arrhythmic events (OR 1.26, 95% CI 1.04-1.52,p=0.018), adjusted for patient's age and time from repair. RA strain did not remain as an independent predictor after adjustment (OR 0.95, 95% CI 0.88-1.01, p=0.124). By ROC curve analysis, only RV strain predicted the presence of arrhythmias (AUC 0.765, 95% CI 0.594-0.936) with a cut-off value of < -11.2% (sensitivity 57% and specificity 94%). Conclusions: Compared with conventional echocardiographic parameters, 2D strain measurements of the right heart (particularly RV) are associated with the occurrence of arrhythmic events and RV 2D strain may be useful in risk stratification of patients with rTOF.