
The Circadia pacemaker was one of the very few devices that had a lead-borne thermistor to measure cental venous temperature (CVT) as a sensor for rate-response.
A unique feature of this pacemaker was an iridium-oxide (IrOx)-coated button welded to the can. It was believed that this button would improve unipolar IEGM sensing and reduce unipolar pacing thresholds (it didn’t). Continue reading


One of the indicators of metabolic demand that has been used for controlling the rate of pacemakers is central venous blood temperature (CVT).









Transneuronix, Inc. was founded in 1995 and was based in Mount Arlington, New Jersey. It was acquired by Medtronic in 2005.
Transoma was the name that Data Sciences International of St Paul, MN adopted in 2003 when it re-fucused its animal telemetry implant business to develop an implantable wireless system to capture electrocardiogram data for diagnosing human cardiac arrhythmias, as well as to monitor the electrical activity of the heart and transmit data from the patient’s home to monitoring centers.
Sicel Technologies, Inc. was founded in 1999 and was based in Morrisville, NC. It ceased operations in 2010 after it declared bankruptcy.