Karen Gomes Ordovas MD, Presenter: Nothing to Disclose

Marcus Carlsson MD, PhD, Abstract Co-Author: Nothing to Disclose

Katy Lease MD, Abstract Co-Author: Nothing to Disclose

Elyse Foster MD, Abstract Co-Author: Research grant, Boston Scientific Corporation Research grant, Evalve, Inc

Alison Meadows MD, Abstract Co-Author: Nothing to Disclose

Alastair Martin, Abstract Co-Author: Research Consultant, Medtronic, Inc Research Consultant, SurgiVision, Inc Research grant, SurgiVision, Inc Research grant, Koninklijke Philips Electronics NV

Michael D. Hope MD, Abstract Co-Author: Nothing to Disclose

Loi Do, Abstract Co-Author: Nothing to Disclose

Charles Bernard Higgins MD, Abstract Co-Author: Nothing to Disclose

Maythem Saeed DVM, PhD, Abstract Co-Author: Nothing to Disclose

To determine if magnetic resonance (MR) can detect early left ventricular (LV) dysfunction in patients with pulmonary regurgitation after repair of tetralogy of Fallot (ToF) and preserved or mildly reduced left ventricular ejection fraction (LVEF).

Nineteen patients (mean age 33 years ± 13; 7 males) were prospectively recruited for this study. Ten healthy volunteers (mean age 32 years ± 4; 5 males) were the controls. Short axis cine MR images were acquired for ventricular volumetric analysis. Velocity-encoded cine sequence was performed for measurement of pulmonary regurgitant fraction (PRF). Tagging MR images were acquired in the short axis plane at the basilar, midventricular and apical levels for calculation of myocardial strain. Mid wall eularian circumferential strain, peak rotation, and time to peak rotation were calculated for the entire cardiac cycle. Mean values were compared between the groups using the T test. Statistical significance was set at p-value < 0.05.

Patients had mild to severe PRF (mean = 36% ± 17) and 16 persons had right ventricular dysfunction (mean right ventricular ejection fraction = 44% ± 9). The mean LVEF was 57% ± 7. Patients had decreased LV circumferential strain at the basilar (-15.5% vs -18.0%; p<0.001) and apical (-14.1% vs -17.3%; p<0.01) levels and decreased peak rotation at the basilar level (2.4° vs 4.3°; p<0.001). In addition, patients had delayed LV peak rotation in the basal (6.8 vs 4.2; p<0.01) and midventricular (8.6 vs 4.9; p<0.01) slices, resulting in a shorter diastolic phase.

MR imaging can detect early LV dysfunction in patients with preserved or mildly reduced LVEF after repair of ToF. The abnormal rotation at the basilar level with preserved rotation at the remaining ventricular regions indicates that negative ventricular-ventricular interaction resulting in intraventricular dyssynchrony likely plays a central role in early LV dysfunction in these patients.

LV dysfunction is a strong predictor of mortality after repair of ToF. MR can detect early LV dysfunction and is a promising technique for predicting global left ventricular dysfunction.

Ordovas, K, Carlsson, M, Lease, K, Foster, E, Meadows, A, Martin, A, Hope, M, Do, L, Higgins, C, Saeed, M, Tagging MRI for Early Detection of Regional LV Dysfunction after Repair of Tetralogy of Fallot.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9003438.html