Purpose
Magnetic Resonance Angiography (MRA) is routinely used in patients with atrial fibrillation (AF) candidates to catheter ablation (CA) to delineate left atrial (LA) dilation as predictors of AF recurrence,
pulmonary veins (PVs) anatomy to leading CA and left atrial appendage (LAA) morphology that is involved to silent ischemia.
Our purpose was to compare MRA to a 3D ECG-gated sequence.
Methods and Materials
MRA and Steady State Free Precession Whole Heart (SSFP-WH) were performed in thirty-one consecutive patients,
23 (74.2%) men,
mean age 56.4±11 years.
The study was performed using a 1.5 T (Tesla) MR.
The breath-hold,
no ECG-gated (Electrocardiogram-gated) MRA was performed using 0,15 ml/kg paramagnetic contrast agent.
SSFP-WH imaging was acquired in four-chamber orientations,
free-breathing,
prospectively ECG-gated synchronized with atrial diastole.
Results
LA volume calculated with SSFP-WH (average volume: 109.25 ml; range: 41.43-174 ml; SD±93.7 ml) was larger than MRA (average volume: 88.41 ml; range: 23.76-154.46 ml; SD±35.4 ml) according to the correlation: SSFP-WH volume=MRA volume+24 ml (R=0.97).
The double-blind analysis of PVs anatomy for MRA showed a concordance of 100% and of 54.84% between SSFP-WH and MRA.
The LAA Morphology analysis for MRA showed a concordance of 100% and of 50% between SSFP-WH and MRA.
Conclusion
Left atrial maximum volume (LAMV) has already been confirmed as the most reliable predictor of AF recurrences after AF transcatheter ablation1 and this is the reason why its exact quantification is still now a theme of crucial importance.
To date LAMV is routinely assessed by MRA and at the same time furnish precious information also on the morphology of auricle and PVs.
Unfortunately,
MRA,
in not synchronized with the diastole phase,
and thus targeted at the maximum atrium volume,
yields LA volume values consists about...
References
1 D’Ascenzo F, Corleto A,
Biondi-Zoccai G,
Anselmino M,
Ferraris F,
di Biase L,
Natale A,
Hunter RJ,
Schilling RJ,
Miyazaki S,
Tada H,
Aonuma K,
Yenn-Jiang L,
Tao H,
Ma C,
Packer D,
Hammill S,
Gaita F.
Which are the most reliable predictors of recurrence of atrial fibrillation after transcatheter ablation?: a meta-analysis.
Int J Cardiol.
2013 Sep 1;167(5):1984-9.
2 Patel A,
Fatemi O,
Norton P,
West J,
Helms A,
Kramer C,
Ferguson J: Cardiac cycle dependent left atrial dynamics: implications for catheter ablation...
