The Association Between Atrial Fibrillation Burden and Quality of Life: A Substudy of the SHAM-PVI Trial

The SHAM-PVI (A Randomized Sham-Controlled Study of Pulmonary Vein Isolation in Symptomatic Atrial Fibrillation) trial demonstrated that pulmonary vein isolation (PVI) reduces atrial fibrillation (AF) burden and enhances quality of life (QoL). However, the relationship between QoL improvements and actual reductions in AF burden remains insufficiently studied, particularly with regard to the potential influence of the placebo effect.

This study sought to investigate the relationship between AF burden and patient-reported QoL outcomes in the context of a sham-controlled, double-blind trial comparing PVI to a sham procedure.

This is a secondary analysis of the SHAM-PVI trial involving 126 patients with symptomatic paroxysmal or persistent AF. Participants were randomized to cryoballoon PVI or a sham procedure, with AF burden measured continuously via an implantable loop recorder. QoL was assessed using the Atrial Fibrillation Effect on Quality-of-Life (AFEQT), Mayo AF-Specific Symptom Inventory (MAFSI), and 36-Item Short Form Health Survey (SF-36) instruments. Associations between AF burden and QoL were analyzed using regression models, including interaction terms for treatment group.

Reduction in geometric mean AF burden was statistically significantly associated with improvements in overall AFEQT score (estimate 0.971; 95% CI: 0.962 to 0.981; P < 0.0001), MAFSI symptom severity and frequency, and multiple SF-36 subdomains. The relationship between the geometric mean AF burden and QoL outcomes was constant between the 2 groups. Symptom-specific analysis highlighted stronger associations between AF burden and palpitations, dizziness, shortness of breath, tiredness, unable to exercise, and weakness.

In this secondary analysis of the SHAM-PVI trial, there was a statistically significant relationship observed between AF burden reduction and QoL improvements. The study provides robust evidence for the use of AF burden as a marker of success and further reinforces that PVI exhibits no placebo effect.