• Acute treatment with elimination of AF episodes [ Time Frame: 12 months ] [ Designated as safety issue: No ]
  
• Death, stroke, and hospitalization for recurrence of AF [ Time Frame: within 12 months of treatment ] [ Designated as safety issue: Yes ]
  

• Acute treatment success [ Time Frame: 60 days ] [ Designated as safety issue: No ]
  

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia affecting an estimated 2.2 million persons in the United States (US). In addition to being debilitating, AF has been identified as a leading risk factor for stroke. AF is often associated with structural heart disease, but a substantial number of AF patients have little or no detectable structural heart disease. A patient with AF is up to 5 times more likely to have a stroke than the general population.

Recently, it has been demonstrated that for a significant portion of AF patients (80% - 95 %) the arrhythmia originates in one of the four pulmonary veins (PV's). Furthermore, it has been shown that isolation of this arrhythmia by ablation can, in the majority of patients (50-70%), eliminate or markedly reduce episodes of AF. Currently, there are a number of modalities being investigated to treat AF. They include radiofrequency, laser, thermal, cryo, microwave, and ultrasound ablation of targeted areas in the atrium and/or PVs.

Comparison(s): Clinical success of High Intensity Focused Ultrasound (HIFU) Ablation for Pulmonary Vein Isolation in the treatment of Atrial Fibrillation, compared to medical therapy with anti-arrhythmic drugs (AADs).