In patients with atrial fibrillation (AFib) and left ventricular systolic dysfunction (LVSD), catheter ablation was associated with substantial improvement in LVEF regardless of late gadolinium enhancement (LGE) status, while 12-month LVEF and normalization rates were lower in patients with LGE present, according to results from the CAMERA-MRI II trial published June 8 in JACC: Clinical Electrophysiology.

Louise Segan, MBBS, MPH, PhD, et al., included 80 patients who underwent catheter ablation – half were LGE positive and the other half were LGE negative. Investigators evaluated change in LVEF, LVEF normalization, AFib burden, functional capacity and heart failure hospitalization at 12 months post procedure.

Both patients with and without LGE saw substantial improvement in LVEF (LGE positive: ΔLVEF +20.3±11.0%; LGE negative: +21.7±11.8%; p=0.578 for between-group difference in change) as well as improvements in biomarkers, functional status and quality of life.

At 12 months, unadjusted LVEF was lower in patients with LGE (49.1±11.3% vs. 54.5±9.0%; p=0.019) and rates of LVEF normalization were also less in the LGE-positive group (LVEF ≥50% in 52% vs. 82% in LGE negative; p=0.004). The authors note that after adjustment "LGE status was not independently associated with 12-month LVEF (p=0.849)." Other outcomes like arrhythmia-free survival and AFib burden reduction were similar between groups.

Segan and colleagues also found an association between higher LGE burden (>20%) and attenuated LVEF recovery. "LGE largely functions as a marker of underlying myocardial substrate, rather than an independent determinant of postablation recovery," they write. "However, fibrosis burden appeared to modulate the magnitude and trajectory of reverse remodeling, particularly at higher scar burden (i.e., >20%), supporting a graded, rather than binary, association between myocardial substrate and recovery."