UCSF Medical Center doctors implant new cardiac defibrillator to diagnose arrhythmias

Doctors at UCSF Medical Center implanted a new cardiac defibrillator that uses a single-lead to sense vital changes in the heart rhythm on March 14, 2013, becoming one of the first heart centers in Northern California to perform this procedure.

“The implantation procedure is very straightforward and identical to that of a standard single lead device, but allows us to monitor rhythm changes in both the atrial and ventricular chambers without the need for two leads”

"The implantation procedure is very straightforward and identical to that of a standard single lead device, but allows us to monitor rhythm changes in both the atrial and ventricular chambers without the need for two leads," said Dr. Zian H. Tseng, a cardiac electrophysiologist and an associate professor in the UCSF Division of Cardiology, who implanted the first device at UCSF Medical Center.

Single-chamber implantable cardioverter defibrillator (ICDs) are sophisticated electronic devices that use a thin flexible wire, known as a lead, to monitor the normal activity of the heart, and deliver a life-saving electrical shock when the heart rate becomes dangerously fast or stops altogether.

The Food and Drug Administration granted final approval for the BIOTRONIK DX System in late February 2013, and the device was implanted at the UCSF Heart & Vascular Center as a new option for gaining important and useful atrial signal information without needing to implant multiple leads.

"This new technology improves the defibrillator's ability to diagnose arrhythmias, which is critical to prevent painful inappropriate shocks," said Dr. Byron Lee, a cardiac electrophysiologist and an associate professor in the Division of Cardiology at UCSF Medical Center.

ICDs are very useful in preventing sudden cardiac death in patients with ventricular tachycardia - a fast heart rate - or for diagnosing atrial fibrillation, which is a quivering or irregular heartbeat. Approximately 70,000 people are implanted with ICDs each year. Traditional standard single-chamber ICDs come with limitations. The devices are designed only to sense changes in ventricular rhythm and are unable to sense atrial arrhythmias, such as atrial fibrillation, correctly. This can result in an increased risk of an inappropriate shock or a stroke if AF is not detected.

The DX System expands the diagnostic capabilities of a standard single-chamber ICD with a single-lead. In addition to featuring sophisticated sensors that allow for atrial monitoring and enhanced arrhythmia diagnosis, the system uses an innovative floating atrial dipole. This allows physicians, for the first-time in an ICD, to capture atrial-sensing capabilities with only one lead.

When combined with the Lumax 740 VR-T DX device, the system provides robust and reliable atrial signals. Additionally, the technology helps discriminate supraventricular tachycardias (SVTs), AF and atrial flutter to reduce the risk of inappropriate shocks.

The DX System also integrates with BIOTRONIK Home Monitoring®, allowing physicians to remotely follow their DX patients' clinical and device statuses daily—at anytime, anywhere in the world.

The cellular-based system has demonstrated the ability to detect clinically relevant events, including silent, asymptomatic arrhythmias, and device related issues, allowing for earlier medical intervention.