Intracardiac acoustic radiation force impulse imaging: a novel imaging method for intraprocedural evaluation of radiofrequency ablation lesions.


BACKGROUND: Arrhythmia recurrence after cardiac radiofrequency ablation (RFA) for atrial fibrillation has been linked to conduction through discontinuous lesion lines. Intraprocedural visualization and corrective ablation of lesion line discontinuities could decrease postprocedure atrial fibrillation recurrence. Intracardiac acoustic radiation force impulse (ARFI) imaging is a new imaging technique that visualizes RFA lesions by mapping the relative elasticity contrast between compliant-unablated and stiff RFA-treated myocardium. OBJECTIVE: To determine whether intraprocedure ARFI images can identify RFA-treated myocardium in vivo. METHODS: In 8 canines, an electroanatomical mapping-guided intracardiac echo catheter was used to acquire 2-dimensional ARFI images along right atrial ablation lines before and after RFA. ARFI images were acquired during diastole with the myocardium positioned at the ARFI focus (1.5 cm) and parallel to the intracardiac echo transducer for maximal and uniform energy delivery to the tissue. Three reviewers categorized each ARFI image as depicting no lesion, noncontiguous lesion, or contiguous lesion. For comparison, 3 separate reviewers confirmed RFA lesion presence and contiguity on the basis of functional conduction block at the imaging plane location on electroanatomical activation maps. RESULTS: Ten percent of ARFI images were discarded because of motion artifacts. Reviewers of the ARFI images detected RFA-treated sites with high sensitivity (95.7%) and specificity (91.5%). Reviewer identification of contiguous lesions had 75.3% specificity and 47.1% sensitivity. CONCLUSIONS: Intracardiac ARFI imaging was successful in identifying endocardial RFA treatment when specific imaging conditions were maintained. Further advances in ARFI imaging technology would facilitate a wider range of imaging opportunities for clinical lesion evaluation.





Published Version (Please cite this version)


Publication Info

Eyerly, Stephanie A, Tristram D Bahnson, Jason I Koontz, David P Bradway, Douglas M Dumont, Gregg E Trahey and Patrick D Wolf (2012). Intracardiac acoustic radiation force impulse imaging: a novel imaging method for intraprocedural evaluation of radiofrequency ablation lesions. Heart Rhythm, 9(11). pp. 1855–1862. 10.1016/j.hrthm.2012.07.003 Retrieved from

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.



Tristram Dan Bahnson

Professor of Medicine

Jason Koontz

Associate Professor of Medicine

David Bradway

Research Scientist, Senior

David P. Bradway is a research scientist in the Biomedical Engineering Department at Duke University. He earned his Ph.D. in biomedical engineering in 2013 from Duke. Afterward, he was a guest postdoc at the Technical University of Denmark (DTU), supported by a Whitaker International Program Scholarship. He has conducted research internships at the Cleveland Clinic Foundation, Volcano Corporation, and Siemens Healthcare, working on ultrasound research since 2002.


Patrick D. Wolf

Associate Professor of Biomedical Engineering

My research is primarily in the area of advanced instrumentation for diagnosis and treatment of electrophysiological problems. This research covers two primary organ systems: the heart and the brain.

One thrust of the cardiac-based work is centered on atrial fibrillation and in particular on very low energy atrial defibrillation strategies. The goal is to produce a device that can defibrillate the atria with a painless series of electrical impulses. A second area of interest is the study of the biophysics of radio frequency ablation of the heart. A third avenue of research in the cardiac area is the development of new instruments and techniques for tracking interventional devices within the body without the use of ionizing radiation. These devices primarily rely on ultrasound technology. There is a strong collaborative effort in this area with the Duke Ultrasound group in the Department of Biomedical Engineering. The long term goal of this work is to develop technology to deliver image-guided therapy to target tissues in the heart and other organs.

In neuroengineering, we are currently developing a "brainchip" that would telemeter information recorded directly from neurons in the brain to a remote device. This IC based technology is being developed for application in neuro-prosthetic or brain controlled devices. There is a close collaboration on this project between our lab and the laboratory of Dr. Miguel Nicolelis the Department of Neurobiology. We are also developing advanced neural recoding systems to use on unrestrained, untethered animals as they learn to perform certain tasks.

Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.