Cardiac event recorders help doctors and nurses monitor a heart’s electrical activity outside of the care setting. And as these recorders have become more common, they’ve also started getting smaller.
A new, implantable monitoring device is helping improve cardiac and stroke care by detecting potential problems before an event occurs.
It is a loop recorder that’s implanted into the patient’s chest wall. It is used in patients who may have irregular heartbeats, or who have had fainting episodes. The device is less than half the size of its predecessors, and that is making a notable difference in both frequency of use and effectiveness, says Dr. Thomas Williams, a board-certified electrophysiologist with Centennial Heart at Summit, a part of TriStar Summit Medical Center in Hermitage, Tenn.
“The unit we placed before looked like a thumb drive in terms of thickness and overall size,” Dr. Williams says. “It required a surgical procedure to insert, because a pocket had to be formed under the skin and then sewn up once the device was placed. The new device’s size is more like half a stick of Dentyne gum, and about that thick. We are able to inject it through a small incision into the muscle layer below the skin. That means no general anesthesia, so it’s much easier on the patient. .”
In addition to being much smaller, the device has a greatly extended operating life. It can continuously monitor a patient’s heart for up to three years. That means someone can be diagnosed following an episode or series of episodes, and then leave the device in place if they wish. Ongoing monitoring is done through the manufacturer’s Carelink® Network, so medical staff is alerted if and when the patient’s cardiac condition changes. That is a huge benefit when dealing with irregular heartbeats, or AFib, says Dr. Williams.
“AFib is one of the most common and undertreated heart rhythm disorders in America,” he says. “When left untreated, AFib increases the chance of stroke and heart failure. General monitors are left on for 24 or 48 hours, and event monitors can be left on for three or four weeks, but then those have to come off. This stays in place, so if a slow or fast heartbeat is detected, or the patient has losses of consciousness, there is data for the physicians to examine.”
Dr. Williams and his team have been able to diagnose AFib in several patients, but also identify individuals who have had a cryptogenic stroke, or a stroke that did not involve any vascular issues in the head — and had no symptoms before or after the event.
“We found that a significant number of these patients were having abnormal heart rhythms, which increased their risk of stroke from blood clots forming in the heart,” Dr. Williams says. “Because they had been asymptomatic, they were not getting preventative treatment for stroke, which would involve taking aspirin and perhaps Plavix, or Coumadin or another blood thinner. By having the information from the device, we can step in and begin those treatments.”
What’s more, he says, even patients who have had this type of stroke can have their likelihood of a second event greatly reduced by the device. That has led to some serious bonding between patient and technology.
“Many people want it left in even after all our questions have been answered in terms of what is going on with them,” Dr. Williams says. “They want that device in ‘just in case,’ and so we can leave it there until the battery runs out – in about three years.”