Table 2. Efficacy Outcomesa.
| No. (%) | Risk difference (95% CI)b | Hazard ratio (95% CI)c | P valued | ||
|---|---|---|---|---|---|
| MRI-guided (N = 407) | PVI only (N = 408) | ||||
| Primary outcome | |||||
| Atrial arrhythmia recurrence or repeat ablatione | 175 (43.0) | 188 (46.1) | −0.016 (−0.078 to 0.048) | 0.95 (0.77 to 1.17) | .63 |
| Components of the primary outcome (atrial arrhythmia types)f | |||||
| Atrial fibrillation | 129 (31.7) | 147 (36.0) | −0.029 (−0.089 to 0.036) | 0.90 (0.71 to 1.14) | .37 |
| Atrial flutter | 33 (8.1) | 26 (6.4) | 0.021 (−0.020 to 0.064) | 1.30 (0.78 to 2.17) | .32 |
| Atrial tachycardia | 7 (1.7) | 6 (1.5) | 0.003 (−0.018 to 0.024) | 1.18 (0.40 to 3.50) | .77 |
| Secondary outcomes | |||||
| Atrial arrhythmia recurrence, repeat ablation, or new atrial arrhythmia medicatione,g | 183 (45.0) | 196 (48.0) | −0.016 (−0.080 to 0.048) | 0.95 (0.78 to 1.16) | .62 |
| Repeat ablationh | 57 (14.0) | 72 (17.6) | −0.028 (−0.070 to 0.013) | 0.80 (0.56 to 1.12) | .20 |
| Post hoc outcome | |||||
| Atrial arrhythmia recurrence, repeat ablation, new atrial arrhythmia medication or cardioversione,g | 187 (45.9) | 198 (48.5) | −0.013 (−0.076 to 0.052) | 0.96 (0.79 to 1.17) | .69 |
Abbreviations: MRI, magnetic resonance imaging, PVI, pulmonary vein isolation.
Outcomes were evaluated in randomized patients who remained in follow-up after the 90-day blanking period.
Calculated as the difference in risk of the outcome in the MRI-guided group vs the PVI-guided group by day 275 after the start of the blanking period (95% CIs are percentile CIs from 2000 bootstrap samples).
Computed using Cox regression with baseline hazards stratified by baseline fibrosis (<20% vs ≥20%).
Computed from the log-rank test stratified by baseline fibrosis (<20% vs ≥20%).
The analysis evaluates the listed events as a composite outcome, with the first occurrence of any of the listed events counted as the composite event for the analysis.
Indicates atrial arrhythmia type for atrial arrhythmia recurrences designating the primary outcome.
Only new initiations of atrial arrhythmia medications are included in the atrial arrhythmia medication component of this composite outcome.
Repeat ablation is counted as an outcome even if there was an atrial arrhythmia recurrence, cardioversion, or start of atrial arrhythmia medications prior to the repeat ablation date.