In patients with persistent atrial fibrillation (AF), standard treatment with pulmonary vein isolation (PVI) ablation has shown similar results to more extensive ablation in other areas of the center. The outcomes of the randomized, controlled SUPPRESS-AF trial were presented at this yr’s ESC Congress 2024 in London, UK (30 August – 2 September).
In our multicenter study, the addition of further ablation targeting low-voltage areas that trigger arrhythmias didn’t reduce AF reoccurrence at 1 yr in your complete cohort but showed promising ends in the vital subgroup with advanced left atrial enlargement, which affects roughly half of patients with persistent AF.
Dr. Masaharu Masuda, lead creator, Kansai Rosai Hospital, Hyogo, Japan
He adds: “The outcomes of this study are more likely to change practice, shifting the emphasis to shorter and simpler pulmonary vein ablation without adding one other ablation presently. Further research into simpler methods and patient selection is awaited to extend the efficacy of additional ablations.”
In AF, the electrical signals in the center that regulate blood pumping from the upper chambers to the lower chambers are chaotic. This could cause blood to pool within the upper chambers and form blood clots that may travel to the brain and cause an ischemic stroke.
When medications fail to treat arrhythmias, catheter ablation is used to create scar tissue within the upper left atrium of the center, thereby stopping interfering electrical signals, often from the pulmonary veins, that would cause the abnormal rhythm.
During pulmonary vein isolation (PVI) ablation, catheters inserted into the center deliver radiofrequency energy that destroys the vein tissue causing atrial fibrillation.
Nevertheless, AF reoccurrence after PVI stays high. In patients with persistent AF, there isn’t any established ablation strategy apart from PVI. Nevertheless, low-voltage area ablation (LVA)—through which areas of low bipolar voltage triggering arrhythmias are targeted—is often performed, although its efficacy is unknown.
To learn more, the SUPPRESS-AF trial enrolled 1,347 patients with persistent AF undergoing first-time ablation at eight cardiology centers in Japan. Of those, 343 (25.5%) patients (mean age 74 years; 49% women) had left atrial LVA (involving ≥ 5 cm² of left atrial surface area) and were randomized 1:1 to receive conventional PVI alone (control group; 171 patients) or the addition of LVA ablation after PVI (170 patients).
After ablation, arrhythmia reoccurrence was detected by 24-hour continuous ECG monitoring at 6 and 12 months after ablation and by twice-daily home ECG recordings for 1 yr.
For the first endpoint of reoccurrence of atrial fibrillation and atrial tachycardia (abnormal heart rhythm) without antiarrhythmic drugs after one yr, there was no significant difference between the groups: 61% of patients who underwent additional left coronary artery ablation and 50% of patients who received standard treatment didn’t experience a reoccurrence.
Similarly, the liberty from reoccurrence of atrial fibrillation/atrial fibrillation with antiarrhythmic drugs didn’t differ between the 2 groups (left ventricular ablation in 63% of patients versus 55% of normal patients).
Nevertheless, in a subgroup of patients with left atrial enlargement (diameter ≥45 mm) — when considered one of the center’s upper chambers (the left atrium) becomes larger than normal attributable to aspects reminiscent of hypertension or heart valve problems — low-voltage regional ablation reduced the reoccurrence of atrial fibrillation by 40%.
There was no difference in the speed of significant complications reminiscent of stroke, which was very low in each groups (1.7% vs 1.8%).
“Directed ablation of diseased myocardium is often performed, but our results show that routine addition of PVI isn’t really useful,” Dr. Masuda said. “This ablation should only be performed in cases of advanced atrial remodeling. A vital next step will likely be to try to know how this procedure could be improved in patients with persistent AF.”