Feature | July 15, 2011| Dave Fornell

Intra-Cardiac Echo Aids EP Ablations, Structural Heart Procedures

Users say ICE offers more versatile imaging than TEE and will play a key role in transcatheter valve replacements

Catheter-based intra-cardiac echocardiography (ICE) is an imaging modality similar to intra-vascular ultrasound (IVUS). It allows imaging inside the heart to visualize cardiac structures and blood flow using Doppler imaging. The standard-of-care for this type of imaging is usually transesophageal echo (TEE), but ICE proponents say the intra-cardiac modality has several advantages.

The image quality is comparable to TEE, but the real advantage is the cardiologist controls the catheter instead of a sonographer, eliminating a second operator, explains Jay Lee, medical director of electophysiology (EP) at Hoag Heart and Vascular Institute, Newport Beach, Calif. He said ICE also provides more versatility than the limited view provided by TEE, because the catheter can be maneuvered to see more inside the heart and the aortic root. Unlike TEE, ICE does not require general anesthesia.

ICE has applications for structural heart imaging of the left atrial appendage (LAA), to aid in septal defect closures and visualizing the fossa ovalis, and plays a role in transcatheter valve replacement. It also is used in EP procedures for ablation catheter guidance.

EP Guidance
Lee primarily uses ICE for transcatheter EP ablations to treat atrial fibrillation (aFib), ventricular tachycardias and the pulmonary vein. In EP transcatheter ablation procedures, ICE confirms the exact location of the catheter tip to aid with more accurate ablations. ICE also can  help with safety monitoring of the pericardial space for tamponade or pericardial effusion caused in rare cases by either the transeptal puncture or the ablation, Lee said.

“It’s a wonderful tool to help us guide our procedures more accurately,” Lee said. “We also have found some new areas for ICE in the EP lab…I find it very useful with access and safety. We also find it useful for treating ventricular tachycardias.”
Hoag uses the Carto EP mapping system, which is compatible with Siemens’ ICE system. GE, Boston Scientific and St. Jude also offer ICE systems.

“It’s very practical when we are performing aFib catheterizations, because it offers real-time imaging of the heart,” Lee said.
He uses a transeptal puncture to feed the imaging catheter into the atrium he is ablating. Lee says a transeptal puncture is safer than other entry options, and used the ICE catheter to visualize exactly where the transeptal puncture is made.
The ICE system is used to create a map of the pulmonary artery and the atriums, and can help create a 3-D map of the ventricular anatomy, including details of the papillary muscles.  

ICE Catheters
Single element rotational (also referred to as radial) imaging catheters offer a similar view as IVUS and are good for close-up, near-field imaging, Lee said. Phased array ICE catheters allow side-fire, wedge-shaped images that are similar to conventional ultrasound imaging. Lee said phased array catheters offer better far-field imaging.

From his experience, Lee said rotational imaging offers about 2 cm field-of-view (FOV) of clear imaging (Boston Scientific says its system images up to 14 cm), which is good for the septum and the fossa ovalis. But due to the limited FOV, he said most EP labs will find phased array systems more useful, with vendors claiming imaging depths of up to 30 cm.

Boston Scientific’s Ultra ICE system uses radial ICE imaging, which is not steerable and is limited to 2-D imaging. The Siemens, GE and St. Jude systems are steerable and offer 2-D, color and spectral Doppler capabilities.

These catheters cost a couple thousand dollars each, which has led to resistance to widespread adoption, Lee said.

The Future of ICE
Lee said ICE works in tandem with EP mapping systems now, but further integration in the future will lead to more procedural accuracy. Mapping systems can import computed tomography (CT) images to use as a map of the heart, but the image is not in real time. Lee expects future systems to allow registration of the echo image with the mapping system for live imaging.

ICE is expected to become increasingly important to better guide an increasing number of transcatheter ablation procedures. Once transcatheter aortic and mitral valve heart valve replacement and LAA occlusion devices gain U.S. Food and Drug Administration (FDA) clearance, ICE is expected to see increased use for the accurate deployment of these devices.   

Related Content

iRhythm Technologies, ZIO continuous cardiac monitoring service, myZIO app, irregular heartbeat symptoms, reporting

Image courtesy of iRhythm Technologies

Technology | ECG Monitoring Services| November 19, 2015
iRhythm Technologies Inc. announced the launch of new patient engagement tools to enhance the diagnosis of cardiac...
wearable Holter monitors, iRhythm, ziopatch, zio patch

iRhythm Technologies Zio Patch was among the first of a new generation of simplified, wearable Holter monitors designed to increase ease of use and patient compliance to increase detection of arrhythmias that may lead to stroke.

Feature | Holter Monitoring Systems| November 16, 2015 | Judy Lenane, RN, MHA
One-third of ischemic strokes are classified as cryptogenic.
Medtronic, Micra TPS, Global Clinical Trial, results

Image courtesy of Medtronic

News | Pacemakers| November 11, 2015
 Medtronic plc announced that the Medtronic Micra Transcatheter Pacing System (TPS) was successfully implanted in...
LivaNova, Platinum, ICD, CRT-D, launch, Europe and Japan

Image courtesy of LivaNova PLC

News | Implantable Cardioverter Defibrillators (ICD)| November 04, 2015
LivaNova PLC, formerly Sorin Group, launched Platinum, a new range of implantable cardiac defibrillators (ICDs) and...
StopAfib.org, atrial fibrillation, AF-related stroke, patient engagement materials

Infographic courtesy of StopAfib.org

News | Stroke| November 03, 2015
In recognition of World Stroke Day, the patient-focused organization StopAfib.org launched a diverse set of materials...
News | Heart Failure| November 02, 2015
Medical device developer Cardionomic Inc. announced that it has received $20 million in Series A financing. Investors...
Boston Scientific, CE Mark, MRI conditional labeling, CRT-Ds, ICDs

X4 CRT-D system image courtesy of Boston Scientific

News | EP Lab| October 30, 2015
Boston Scientific Corp. has received CE Mark on magnetic resonance imaging (MRI) conditional labeling for the current...
Stereotaxis, Niobe remote magnetic navigation system, respiratory compensation, cardiac ablation
Technology | Robotic Systems| October 28, 2015
Stereotaxis Inc. announced the worldwide launch of Respiratory Compensation, a new software feature of the company’s...
Praxbind, Pradaxa reversal agent, FDA approval, emergency situations
Technology | Antiplatelet and Anticoagulation Therapies| October 19, 2015
The U.S. Food and Drug Administration (FDA) granted accelerated approval to Praxbind (idarucizumab) for use in patients...
AtriCure, definitive merger agreement, nContact Inc., atrial fibrillation solutions, cardiac ablation
News | Ablation Systems| October 14, 2015
AtriCure Inc. announced it has entered into a definitive merger agreement under which AtriCure has agreed to acquire...
Overlay Init