Cardiac magnetic resonance imaging
Prabhu S, et al. published the following study in J Am Coll Cardiol, 2017.12 This multicenter, randomized clinical trial enrolled patients with persistent AF and idiopathic cardiomyopathy (left ventricular ejection fraction [LVEF]≦45%). After optimization of the rate control, the patients underwent cardiac magnetic resonance (CMR) imaging to assess the LVEF and late gadolinium enhancement, indicative of ventricular fibrosis, before randomization to either catheter ablation (CA) or ongoing medical rate control (MRC). A total of 301 patients were screened; 68 patients were randomized with 33 in each arm. The average AF burden post-CA was 1.6 ± 5.0% at 6 months. In the intention-to-treat analysis, the absolute LVEF improved by 18 ± 13% in the CA group as compared to 4.4 ± 13% in the MRC group (p < 0.0001) and normalized (LVEF ≧50%) in 58% versus 9% (p = 0.0002). In those undergoing CA, the absence of late gadolinium enhancement predicted greater improvements in the absolute LVEF (10.7%; p = 0.0069) and normalization at 6 months (73% vs. 29%; p = 0.0093).