Study prematurely terminated by 23.09.2025 due to very slow patient recruitment.

The aim of this study is to investigate whether renal denervation can reduce arrhythmia burden in patients with recurrent, paroxysmal atrial fibrillation despite durable pulmonary vein isolation.

Pulmonary vein isolation is the treatment of choice in symptomatic patients with paroxysmal atrial fibrillation. Despite durable pulmonary vein isolation, 15% of patients continue to have episodes of atrial fibrillation because of triggers of atrial fibrillation localized outside the pulmonary veins. Additional ablation of these triggers is difficult because they often cannot be localized. The autonomous nervous system does influence these triggers and modulation of the autonomous nervous system with the goal to reduce sympathetic activity may be an alternative approach to suppress these extra-pulmonary vein triggers. Renal denervation does reduce sympathetic activity and is successfully used to treat drug-resistant arterial hypertension. The combination of pulmonary vein isolation with renal denervation has already been shown to be superior to pulmonary vein isolation alone in patients with paroxysmal atrial fibrillation regarding arrhythmia-free outcome. The investigators hypothesize that renal denervation can suppress atrial fibrillation in patients with recurrent episodes of paroxysmal atrial fibrillation despite durable isolation of the pulmonary veins.

The best way to assess atrial fibrillation burden is with an implantable cardiac monitor (ICM), which the investigators will use both before and after renal denervation, to gather detailed data on daily atrial fibrillation burden.

Inclusion Criteria:

• Informed Consent signed by the subject
• ≥ 18 years of age
• Recurrent, paroxysmal atrial fibrillation post repeat (≥2) pulmonary vein isolation
• Documentation of atrial fibrillation ≥3 months after the last atrial fibrillation ablation procedure by a 12-lead ECG or on a rhythm strip of ≥30 seconds duration
• Either an office systolic blood pressure ≥130 mmHg at the screening visit or antihypertensive drug therapy

Exclusion Criteria:

• Persistent or permanent atrial fibrillation post pulmonary vein isolation
• Left ventricular ejection fraction <40%
• Severe aortic or mitral valve stenosis
• Treatment with amiodaron within the last 3 months
• Mandatory treatment with class I or III antiarrhythmic drugs
• History of reflex syncope, syncope due to orthostatic hypotension or unclear syncope in the past 3 years.
• History of orthostatic hypotension
• Abnormal blood pressure fall during active standing, defined as a progressive and sustained fall in systolic blood pressure from baseline value ≥20 mmHg or diastolic blood pressure ≥10mmHg, or a decrease in systolic blood pressure to <90 mmHg.
• Prior renal denervation
• Renal artery stent or prior renal angioplasty
• Polycystic kidney disease, unilateral kidney, or history of renal transplant
• Estimated glomerular filtration rate (eGFR) < 50mL/min, using the CKD-EPI creatinine equation (Chronic Kidney Disease Epidemiology)
• Female of childbearing potential (age <50 years and last menstruation within the last 12 months), who did not undergo tubal ligation, ovariectomy or hysterectomy.
• Life expectancy <1 year
• Enrolment in interventional studies if the other study does not allow enrolment or if primary endpoint might be affected by study participation.
• Diabetes mellitus type I
• Aortic grafts

The following exclusion criteria will apply after the run-in phase of up to 3 months duration, prospectively in patients which receive a new ICM and retrospectively in patients which already have an ICM implanted:

- Episodes of atrial fibrillation on <6 days in the 3 months run-in phase.