Assessment of left atrial volume by contrast enhanced magnetic resonance angiography.

Left atrial (LA) volume is associated with cardiovascular morbidity, particularly atrial fibrillation. Contrast‐enhanced magnetic resonance angiography (CE‐MRA) visualizes the LA, but the validity of LA volume measurements using this technique has not been evaluated. We performed CE‐MRA and cine magnetic resonance (MR) in 18 consecutive patients referred for CE‐MRA prior to atrial fibrillation ablation. The CE‐MRA LA volumes were compared to cine MR LA volumes at the maximal LA size and at LA end‐diastole using linear regression and limits of agreement analysis. The mean cine MR LA volume was 118 ± 39 mL at maximal LA size and 91 ± 38 mL at LA end‐diastole. Left atrial volume determined by CE‐MRA was 93 ± 38 mL. Although the CE‐MRA LA volume had a strong correlation with the maximal cine MR LA volume (R2 = 0.86, p < 0.001), the 95% limits of agreement were relatively wide (− 54 to 3 mL). The cine MR LA end‐diastolic and CE‐MRA LA volumes were more closely correlated (R2 = 0.98, p < 0.001) with narrow 95% ...