In recent years defects in ICD leads have caused recalls and provoked broad concerns among health care professionals and patients alike about the safety and reliability of ICDs and other implanted cardiac devices. Now a key player in these events proposes that a computer software program can better monitor ICD leads and provide earlier warnings of possible malfunctions.
In a paper published in Circulation: Cardiovascular Quality and Outcomes, Robert Hauser and colleagues report on their evaluation of DELTA (Data Extraction and Longitudinal Trend Analysis), a commercially available automated surveillance tool, in simulated analyses of lead survival in a population of 1,035 patients with the recalled Sprint Fidelis lead and 1,675 patients with the Quattro lead. Lead failures occurred in 8.1% of the Fidelis leads and 1.4% of the Quattro leads during the study. A simulated analysis of the entire cohort “triggered a sustained alert” for the Fidelis lead 13 months after device approval and a full 2 years before the leads were pulled from the market. A second, propensity-matched analysis triggered an alert 22 months after approval and more than one year before withdrawal from the market.
“The software works,” said Hauser, in an AHA press release. “Looking at ICD patients implanted years ago, we showed that the automated program detects medical device problems faster than current approaches.”
“The results of this multicenter study suggest that an active automated surveillance system could have identified this cardiovascular device problem substantially sooner than was achieved through existing postmarket surveillance methods,” the authors wrote. An earlier alert of the Fidelis problem “could have spared thousands of patients the consequences of receiving a device prone to failure, including the risks and costs of lead replacement.”
Here is the press release from the AHA:
Computer software monitoring detects ICD malfunctions sooner
- A computer software monitoring program provides early warning signs that an implantable cardioverter-defibrillator (ICD) might malfunction.
- Using the software during the testing and approval process for devices could decrease the risks of patients receiving defective ICDs.
DALLAS, March 6, 2012 ― A software monitoring program that tracks implantable cardioverter-defibrillator (ICD) function could detect problems with the devices earlier than current monitoring processes, according to new research in Circulation: Cardiovascular Quality and Outcomes, an American Heart Association journal.
ICDs monitor heart rhythms and deliver electric shocks to restore normal rhythm when life-threatening, irregular heartbeats occur. But the surgically implanted devices can malfunction, particularly in the leads, or wires, that connect them to the heart, causing injury or death.
Device manufacturers track repeated malfunctions and issue recalls if they’re widespread. However, often by the time of the recall, thousands of the devices have been implanted in patients worldwide.
“Current monitoring approaches aimed at reducing harm from malfunctioning medical devices rely largely on voluntary reporting of adverse events by manufacturers, possibly leading to missed warning signs and delayed responses to the problems, such as late recalls,” said Robert G. Hauser, M.D., lead study author and senior consulting cardiologist at the Minneapolis Heart Institute at Abbott Northwestern Hospital in Minneapolis, Minn. “We looked at whether using an automated software program to monitor large databases of ICD patients might help us detect potential device-related problems earlier.”
Hauser and colleagues used a commercially available software surveillance program to compare data from about 1,000 patients with recalled leads to about 1,600 patients implanted with ICD leads still on the market. Patients in both databases had their ICDs implanted between 2001 and 2008.
Using the surveillance software, researchers simulated what occurred years earlier. The software detected problems with the recalled leads at least a year before the company had recalled them.
“The software works,” Hauser said. “Looking at ICD patients implanted years ago, we showed that the automated program detects medical device problems faster than current approaches. Pinpointing the malfunction a year earlier in this case could have spared thousands of patients the health risks, costs and inconvenience of receiving a device prone to failure.”
Monitoring newly approved devices could help identify potential problems before the ICDs are introduced on a large scale, he said.
The next step, according to Hauser, is to apply the software to large populations of newly implanted ICD patients, in order to reduce gaps in warning sign detection and action.
Co-authors are Andrew S. Mugglin, Ph.D.; Paul A. Friedman, M.D.; Daniel B. Kramer, M.D.; Linda M. Kallinen, B.S.; Deepa M. McGriff, B.S.; David L. Hayes, M.D. Author disclosures are on the manuscript.
The Minneapolis Heart Institute Foundation and the Abbott Northwestern Hospital Foundation funded the research.