In vitro atrial septal ablation using high-intensity focused ultrasound

J Am Soc Echocardiogr. 2012 Apr;25(4):467-72. doi: 10.1016/j.echo.2011.12.010. Epub 2012 Jan 11.

Abstract

Background: High-intensity focused ultrasound (HIFU) has been applied clinically as a noninvasive therapeutic tool. Atrial septostomy is a palliative treatment for pulmonary artery hypertension. The purpose of this study was to assess the feasibility of atrial septal ablation in vitro using HIFU.

Methods: Fourteen sections of atrial septum from pig hearts were treated. Focused ultrasound energy was applied with an operating frequency of 5.25 MHz at the nominal focal point intensity of 4.0 kW/cm(2) for 0.4 sec in 1-sec intervals.

Results: Lesions were created with ultrasonic exposures ranging from 40 to 120 pulses. There were significant relationships between HIFU exposure time and lesion area on the exposed site (R(2) = 0.3389, P < .0001) and lesion volume (R(2) = 0.6161, P < .0001).

Conclusions: HIFU has the potential to create focal perforations without direct tissue contact. This method may prove useful for noninvasive atrial septostomy.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Echocardiography, Transesophageal
  • Familial Primary Pulmonary Hypertension
  • Feasibility Studies
  • Heart Septum / diagnostic imaging
  • Heart Septum / surgery*
  • High-Intensity Focused Ultrasound Ablation* / methods
  • Hypertension, Pulmonary / surgery
  • In Vitro Techniques
  • Swine
  • Ultrasonography, Interventional