Photoacoustic guidance of left atrium ablation Sophinese - - PowerPoint PPT Presentation

▶
photoacoustic guidance of left
SMART_READER_LITE
LIVE PREVIEW

Photoacoustic guidance of left atrium ablation Sophinese - - PowerPoint PPT Presentation

Jun 19, 2023 472 likes •576 views

Photoacoustic guidance of left atrium ablation Sophinese Iskander-Rizk* 1 , Pieter Kruizinga 1,2 , Antonius FW van der Steen 1,2 and Gijs van Soest 1 1 Biomedical Engineering Department, Thorax center-Erasmus MC, The Netherlands 2 ImPhys, Faculty

slide-1
SLIDE 1

Photoacoustic guidance of left atrium ablation

Sophinese Iskander-Rizk*1, Pieter Kruizinga1,2, Antonius FW van der Steen1,2 and Gijs van Soest1

1Biomedical Engineering Department, Thorax center-Erasmus MC, The Netherlands 2ImPhys, Faculty of Applied sciences, Delft University of Technology, The Netherlands

slide-2
SLIDE 2

RF ablation: a treatment for atrial fibrillation

Atrial Fibrillation:

  • Most common sustained

tachyarrhythmia.

  • Affects 1% of the population
  • ~30% incidence among ischemic heart

patients (4500 new patients/y in NL) Treatment

  • Catheter based RF ablation of ectopic

foci/ conductive substrate

  • L. M. Haegeli, H. Calkins, Catheter ablation of atrial fibrillation: an update, European heart journal, June 2014
slide-3
SLIDE 3

Technology for catheter based ablation

  • Visualization and guidance

− Accurate navigation − Mapping of ectopic foci

Ablation feedback and evaluation

  • Lesion assessment
  • Conductivity assessment
  • Complication prevention
  • J. Kautzner, P. Peichl, The role of imaging to support

catheter ablation of atrial fibrillation, Cor et Vasa 2012

√

~

X X

~

Over ablation Thrombus formation microbbubles Under ablation Gaps, transmurality

√

~ ~

  • Intracardiac echography (ICE)
  • Catheter sensors & tracking systems
  • Late Gadolinium enhancement (LGE) MRI

Several approaches… yet

  • Indirect lesion assessment
  • Repeat interventions: 30-40%
  • Fluoroscopy
  • Electro-anatomical mapping

X √ M`. Njeim et al., Multimodality Imaging for Guiding EP Ablation Procedures JACC: Cardiovascular Imaging Jul 2016,

slide-4
SLIDE 4

How can optics provide a solution?

Photoacoustic imaging

ICE RF catheter with optical fiber

slide-5
SLIDE 5

Photoacoustic imaging

Laser source Ultrasound Transducer array

λ?

slide-6
SLIDE 6

Optimal wavelength for lesion imaging

1- PA spectroscopy on fresh tissue 2- PA spectroscopy on ablated tissue Tissue samples = 14, 23 lesions Transmission mode PA spectroscopy

  • Fresh porcine left atrial wall
  • Sweep 410nm-1000nm in 2 nm steps
  • L12-3v 192 ch. linear array; 7.8 MHz
  • Verasonics Vantage 256

light in sound out

slide-7
SLIDE 7

Spectroscopic lesion characteristics

1: lesion site 3: control site

Pre-ablation Post-ablation

slide-8
SLIDE 8

Spectroscopic features can be used for imaging

Ratio of images at 𝜇1 = 790 nm and 𝜇2 = 930 nm

2 mm 2 mm

Pre-ablation

Post ablation

slide-9
SLIDE 9

Lesion detection: single vs. dual wavelength

Criteria on dual wavelength images

  • 𝑻𝟐 𝒒𝒑𝒕𝒖,𝜇1

𝑻𝟐 𝒒𝒑𝒕𝒖,𝜇2

> threshold → post = TP

  • 𝑻𝟐 𝒒𝒔𝒇,𝜇1

𝑻𝟐 𝒒𝒔𝒇,𝜇2

> threshold → pre = FP Criteria on single wavelength images

  • 𝑻𝟐 𝒒𝒑𝒕𝒖

𝑻𝟐 𝑞𝑠𝑓 > threshold → lesion = TP

  • 𝑻𝟑 𝒒𝒑𝒕𝒖

𝑻𝟑 𝑞𝑠𝑓 > threshold → control = FP

1: lesion site 2,3: control sites

slide-10
SLIDE 10

Conclusion

  • Photoacoustic imaging identifies RF ablation lesions reliably.
  • Photoacoustic imaging is a promising technology for catheter based

ablation for atrial fibrillation

Funding

Acknowledgment Frits Mastik ,Robert Beurskens Geert Springeling, Klazina Kooiman Hans Bosch, Jason Voorneveld, Jovana Janjic, Ayla Hoogendoorn, Min Wu Hendrik Vos, Maaike te Lintel Hekkert, Mirjam Visscher and Alex Brouwer.