ProRhythm, Inc. (PRI) was founded in 1997, under the name Transurgical, to develop High Intensity Focused Ultrasound (HIFU) for use in high-value medical applications. Transurgical changed its name to ProRhythm, Inc. on May 19, 2004.

Since its inception, PRI has developed a strong knowledge base and intellectual property position in HIFU. PRI has begun human clinical trials in Europe and the United States of its initial product, a system employing a minimally invasive HIFU ablation catheter to treat Atrial Fibrillation (“AF”)

ProRhythm's catheter-based system uses HIFU to treat AF in part by the electrical isolation of the pulmonary veins (PV) and ablation within the left atrium of the heart. PV involvement in AF is reported in greater than 95% of AF patients. Pulmonary Vein Isolation (PVI) has long been an essential component of all Cox-Maze surgical procedures, and in recent years in catheter-based ablation procedures that have successfully treated AF.

Focused ultrasound may have significant advantages as an energy source for catheter-based PVI applications. At this time, no other technology has been successful in consistently creating long, continuous lesions in a beating heart during a percutaneous ablation procedure for AF or other arrhythmias. Maintaining tissue contact across long sections of variable heart topography that is beating has been a challenge for most energy sources. PRI’s focused ultrasound, however, is intended to create circumferential therapeutic transmural lesions, isolating PVs, without the need for tissue contact and with minimal applications of energy that last about 1 minute. This should significantly reduce procedure times that routinely last 3-6 hours.

ProRhythm's AF ablation catheter focuses therapeutic ultrasound energy by use of a proprietary dual balloon design, which creates a parabolic gas-fluid interface that reflects and vectors concentrated ultrasound to create a circumferential lesion in the atrium, around the pulmonary vein. PRI has developed it’s HIFU catheter with a variety of balloon sizes to create lesions in a wide range of anatomy. This product portfolio is intended to achieve PVI in at least 95% of AF patients.

PRI has also developed a user-friendly system to control and monitor all aspects of the ablation process including the dual balloon inflation and deflation process and the ultrasound energy application (sonication).

The procedure utilizes the standard EP techniques for accessing the left atrium. Through a small puncture in the groin, a sheath is inserted through the femoral vein and inferior vena cava into the right atrium and then, transeptally into the left atrium. PRI’s catheter is then advanced through the sheath into the left atrium in order to reach and isolate the pulmonary veins.

PV isolation is common to more than 95% of all AF treatments. In certain AF conditions, additional lesions need to be created in the left atrium. PRI believes HIFU can be used to isolate the PVs and create the additional left atrial lesions, and that this approach has the ability for becoming the “gold standard” for treating the great majority of AF patients.

PRI believes that its high intensity focused ultrasound ablation system may have the following significant competitive advantages:

• Fast: Creates continuous circular lesions in the beating heart with minimal energy applications, each lasting about 1 minute, enabling shorter (1 – 2 hours vs. 3-6 hours), economically competitive procedure times.
  
• Safe: May not create damaging levels of energy in intervening or adjacent tissue, intending to minimize adverse side effects (thrombus, charring, phrenic nerve damage). Device design allows the energy to be focused in the left atrial muscle, away from the pulmonary vein, which could minimize the possibility of pulmonary vein stenosis, a serious complication widely associated with RF energy.
  
• Easy: Creates continuous, circumferential, and transmural lesions by transmitting focused energy through blood, and not requiring direct contact with the target tissue.

ProRhythm, Inc. is located in Ronkonkoma, New York in the heart of Long Island.

CAUTION: Investigational device. Limited by United States law to investigational use.