Feasibility of in vivo transesophageal cardiac ablation using a phased ultrasound array

Jacob Robert Werner, Eun Joo Park, Hotaik Lee, David Francischelli, Nadine Barrie Smith

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Over 2.2 million Americans suffer from atrial fibrillation making it one of the most common arrhythmias. Cardiac ablation has shown a high rate of success in treating paroxysmal atrial fibrillation. Prevailing modalities for this treatment are catheter based radio-frequency ablation or surgery. However, there is measurable morbidity and significant costs and time associated with these invasive procedures. Due to these issues, developing a method that is less invasive to treat atrial fibrillation is needed. In the development of such a device, a transesophageal ultrasound applicator for cardiac ablation was designed, constructed and evaluated. A goal of this research was to create lesions in myocardial tissue using a phased array. Based on multiple factors from array simulations, transesophageal imaging devices and throat anatomy, a phased ultrasound transducer that can be inserted into the esophagus was designed and tested. In this research, a two-dimensional sparse phased array with the aperture size of 20.7 mm × 10.2 mm with flat tapered elements as a transesophageal ultrasound applicator was fabricated and evaluated with in vivo experiments. Five pigs were anesthetized; the array was passed through the esophagus and positioned over the heart. The array was operated for 8 ∼ 15 min at 1.6 MHz with the acoustic intensity of 150 ∼ 300 W/cm2 resulting in both single and multiple lesions on atrial and ventricular myocardium. The average size of lesions was 5.1 ± 2.1 mm in diameter and 7.8 ± 2.5 mm in length. Based on the experimental results, the array delivered sufficient power to the focal point to produce ablation while not grossly damaging nearby tissue outside the target area. These results demonstrate a potential application of the ultrasound applicator to transesophageal cardiac surgery in atrial fibrillation treatment.

Original languageEnglish (US)
Pages (from-to)752-760
Number of pages9
JournalUltrasound in Medicine and Biology
Volume36
Issue number5
DOIs
StatePublished - May 1 2010

Fingerprint

fibrillation
phased arrays
Atrial Fibrillation
ablation
lesions
esophagus
surgery
Esophagus
arrhythmia
myocardium
Equipment and Supplies
swine
throats
anatomy
Pharynx
Transducers
Radio
Research
Acoustics
Thoracic Surgery

All Science Journal Classification (ASJC) codes

  • Radiological and Ultrasound Technology
  • Biophysics
  • Radiology Nuclear Medicine and imaging

Cite this

Werner, Jacob Robert ; Park, Eun Joo ; Lee, Hotaik ; Francischelli, David ; Smith, Nadine Barrie. / Feasibility of in vivo transesophageal cardiac ablation using a phased ultrasound array. In: Ultrasound in Medicine and Biology. 2010 ; Vol. 36, No. 5. pp. 752-760.
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Feasibility of in vivo transesophageal cardiac ablation using a phased ultrasound array. / Werner, Jacob Robert; Park, Eun Joo; Lee, Hotaik; Francischelli, David; Smith, Nadine Barrie.

In: Ultrasound in Medicine and Biology, Vol. 36, No. 5, 01.05.2010, p. 752-760.

Research output: Contribution to journalArticle

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