Background: Hypertension (HTN) and atrial fibrillation (AF) commonly co-exist. An improvement in control of HTN in a subset of patients undergoing AF ablation was previously demonstrated by our group. In the present study, we aimed to assess whether left atrial (LA) size based on transthoracic echocardiography may predict the patients who demonstratebetter HTN improvement after ganglionated plexus ablation (GPA) in addition to pulmonary vein isolation (PVI). Methods: This was a retrospective chart review of patients with AF and HTN who underwent GPA+PVI. Patients were divided into 2 groupsbased on LA size: Patients with normal LA size and patients with LA enlargement. Systolic blood pressure (SBP) levelswere compared at baseline, and 3, 6, and 12 months post-ablation. The primary endpoints of the study weremean systolic blood pressure change compared between groups from baseline to 12-months, as well as the absolute difference in systolic blood pressure at 12 months follow-up.Medical therapy for HTN was also assessed before the procedure, and at 12 months post-procedure. Results: 53 patients (37 with LA enlargement, 16 with normal LA size) met inclusion criteria. At 12 months follow-up, SBP was 136.46 ± 22.38 mmHg in patients with LA enlargementand 118.25 ± 9.81 mmHg in patients with normal LA size (estimated difference of 19.04 ± 6.98 mmHg, p = 0.01). Patients with normal LA size were on significantly fewer anti-hypertensive agents at 12 months (2.33 ± 1.49 vs. 1.44 ± 1.21, p < 0.05). Conclusions: In patients undergoing PVI+GP ablation, normal LA size may predict HTN improvement at 12 months post-procedure. Normal LA size may identify hypertensive AF patients for whom autonomic modulation could be an effective therapy.