Introduction: Much attention is paid to right ventricular dysfunction after repair of Tetralogy of Fallot (TOF), yet left ventricular dysfunction has also been shown to be a risk factor for heart failure, arrhythmia, and sudden cardiac death. Vorticity derived by 4D Flow cardiac magnetic resonance (CMR) has been shown to be a more sensitive marker of left ventricular diastolic dysfunction than standard echocardiographic indices in patients with pulmonary hypertension and COPD. In this controlled study, we aimed to compare LV diastolic vorticity in patients with repaired TOF with echocardiographic markers.
Hypothesis: 4D flow derived vorticity will be a more sensitive marker of LV diastolic dysfunction than standard echocardiographic indices in patients with repaired TOF.
Methods: Patients with repaired TOF (n = 9) and healthy controls (n = 10) underwent comprehensive CMR and echocardiographic evaluation. 4D flow vorticity was measured in segmented LV cavity throughout the cardiac cycle. Peak E and A vorticity were compared with echocardiographic counterparts.
Results: Patients with repaired TOF were found to have significantly decreased LV E vorticity (5365 vs 8040 1/s, p=0.008) when compared to controls. There was a marginal statistically significant difference in echocardiographic derived E (94 vs 70 cm/sec, p=0.035) and E/A (2.3 vs 1.4, p=0.023). There was no difference seen in E/e’ (7.3 vs 6.1, p=0.378). No correlations were seen between LV vorticity and standard echocardiographic indices.
Conclusions: 4D flow derived vorticity appears to be a more sensitive marker of LV diastolic dysfunction than echocardiographic indices. Furthermore, the vorticity is independent of standard echocardiographic measures. Given the risk factors associated with LV dysfunction in repaired TOF, decreased vorticity could be an important marker of LV diastolic dysfunction in the evaluation of these patients.