COON RAPIDS, Minn.
Ernest Kramer, of Champlin, has been seeing Randall Stark, M.D., a cardiologist at Metropolitan Heart and Vascular Institute at Mercy Hospital, for three years because of a slow heart rate. He knew a pacemaker was in his future.
What he didn't know was that the one he would receive is one-tenth the size of a standard pacemaker. "It’s absolutely remarkable," Kramer said. "It's a third the size of a triple-A battery."
Two years ago, Kramer, who is 83, had a knee replacement. A year and a half later, an infection developed that was treated with antibiotics. Kramer has full use of his new knee, but the infection complicated the implantation of a traditional pacemaker.
Dr. Stark, concerned about the physical effects the slow heart rate was having on his patient, ordered tests. They showed that Kramer's heart rate was at risk of becoming dangerously slow.
Stephen Remole, M.D., a heart rhythm specialist and Dr. Stark's colleague at Mercy, implanted the Medtronic Micra™ Transcatheter Pacing System (TPS) into Kramer's heart on September 20.
The Micra TPS is an investigational device, not approved in the U.S., and is currently being evaluated in a clinical trial. Kramer is one of approximately 780 patients worldwide who will participate in the study. "My hope for Mr. Kramer is that he will enjoy the benefits of an activity-appropriate heart rate, with a lessor chance for lead infection. Because he has had an infected knee prosthesis from a knee replacement, he would be at extremely high risk for pacemaker lead infection if he had a standard pacemaker," said Dr. Remole. Unlike a standard pacemaker, the Micra TPS does not require a surgical incision in the chest and the creation of a "pocket" under the skin. The miniature device is placed into the heart through a catheter. Instead of connecting to the heart with wires, known as leads, the device attaches to the heart with small tines.
Preliminary study results released in June that showed the Micra TPS was successfully implanted in patients whose ages ranged from 74 to 83 years. There were no major complications, the device performed as expected and electrical values were within normal ranges, according to Medtronic.