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SPHERE Per-AF trial outcomes1

Study purpose and design

SPHERE Per-AF was a randomized controlled trial (RCT) comparing the Affera™ mapping and ablation system with Sphere-9™ catheter to the CARTO®* navigation and mapping system with THERMOCOOL SMARTTOUCH®* SF (STSF) catheter for the treatment of drug-refractory patients with persistent atrial fibrillation. All 420 primary analysis patients received PVI and additional linear lesions were permitted in order to treat documented macro reentrant tachycardias.

Key findings

1.4% primary safety events†
vs. 1% primary safety events
in STSF procedures

73.8% primary effectiveness‡
vs. 65.8% primary effectiveness
with STSF

† For a full list of safety events, review the Sphere-AF manuscript.
‡ Primary effectiveness endpoint definition: The primary effectiveness endpoint was acute procedure failure, repeat ablation at any time, or after three months: recurrence of AF/AFL/AT, cardioversion, or new/re-initiated/increased AAD usage.

Less recurrence through 12 months

Patients treated with the Sphere-9™ catheter observed less recurrence of AF, AT, and AFL throughout the 12-month follow-up period as seen in the Kaplan-Meier curve.

Kaplan Meier curve showing the recurrence of AF, AT, and AFL throughout 12 months after an ablation procedure

Procedural characteristic superiority over STSF

  • 25.1 minutes less → superior skin-to-skin procedural time
  • 26.8 minutes less → superior time between first and last application
  • 28.6 minutes less → superior energy application time
See full summary

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Sphere-360™ (First-in-human) 12-month outcomes

Study purpose and design

This was a prospective, single-arm, multicenter clinical series of the Sphere-360™ conformable single-shot pulsed field ablation catheter for pulmonary vein isolation to treat AF. The study included symptomatic drug refractory PAF patients (n = 85) and evaluated safety, efficacy, and durability.

Key findings

Freedom from AF/AT/AFL

  • 81.8% full cohort
  • 100% PULSE3 optimized waveform subgroup
    • 16 patients treated with the PULSE3 optimized and most recent pulse configuration have completed 12-month follow-up.

PV durability

Lesion durability demonstrated by invasive remapping 75 days post-ablation

  • 99% — per PV (n =100)
  • 96% — per patient (n = 26)

35 patients were treated with the PULSE3 optimized and most recent pulse configuration; 26 subjects completed the optional remapping procedure.

  

Chart showing durability per pulmonary vein (PV) and per patient

Safety outcomes§

0

primary adverse events

  • 0 Esophageal events
  • 0 PV stenosis
  • 0 Phrenic nerve injury
  • 0 Cardiac tamponade
  • 0 Stroke
  • 0 Death

Procedural data§

  • 56 minutes average procedure time
  • ≤ 10 minutes PV transpired time
  • < 6 minutes fluoroscopy time
    • 4 patients treated with zero fluoro

§ See manuscript for full listing of safety events and procedural characteristics.

See manuscript

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Medtronic Affera™ development journey

2014

  • Affera, Inc. started

2015

  • First RF animal study with multiple catheter designs

2017

  • Sphere-9™ catheter design complete

2018

  • First-in-human RF case — world’s first successful large tip focal RF ablation

2019

  • First-in-human PF case — world’s first successful large tip focal PF ablation

2020

  • Sphere-9™ RF/PF AFib study begins and leads to CE Mark in 2023

2021

  • SPHERE Per-AF IDE trial begins and completes enrollment in 2022
  • First-in-human use of Sphere-360™

2022

  • Medtronic acquires Affera, Inc.

2023

  • First commercial case — European limited market release of the Affera™ mapping and ablation system

2024

  • SPHERE Per-AF IDE trial results published

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Affera™ preclinical publications

• Expandable Lattice Electrode Ablation Catheter; Barkagan, et al. 2019.

• Novel Irrigated Temperature-Controlled Lattice Ablation Catheter for Ventricular Ablation; Shapira-Daniels, et al. 2019.

• Feasibility, safety, and durability of porcine atrial ablation using a lattice-tip temperature-controlled radiofrequency ablation catheter; Koruth, et al. 2020.

• Focal Pulsed Field Ablation for Pulmonary Vein Isolation and Linear Atrial Lesions; Koruth, et al. 2020.

• Pulsed-Field Ablation in Ventricular Myocardium Using a Focal Catheter; Yavin, et al. 2021.

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®* Third-party brands are trademarks of their respective owners. All other brands are trademarks of a Medtronic company.

1. Anter E, Mansour M, Nair DG, et al. Dual-energy lattice-tip ablation system for persistent atrial fibrillation: a randomized trial. Nat Med. 2024.

CE mark 0123