Both Appropriate and Inappropriate ICD Shocks Prompt Substantial Use of Healthcare Resources

Implantable cardioverter-defibrillator (ICD) shocks—whether they’re appropriate or inappropriate—often result in emergency department visits, hospitalizations, tests, and invasive procedures, indicating that efforts to reduce shocks could lead to significant cost savings.

Nearly half (46%) of shock events identified in a retrospective study were associated with some form of healthcare use in the week that followed, including hospitalization in 14% of cases and outpatient care in 32%, Mintu Turakhia, MD (VA Palo Alto Health Care System, Palo Alto, CA), and colleagues report in a paper published online February 14, 2017, ahead of print in Circulation: Cardiovascular Quality and Outcomes.

Of note, cardiac catheterization was used in 79% and 51% of patients with appropriate and inappropriate shocks, respectively, but only 6.5% and 5.0% ultimately underwent PCI.

Turakhia told TCTMD that the study was not designed to look at the appropriateness of the care received by patients or its effect on outcomes, pointing out that “the care may very well have been reasonable in the majority of situations.”

But, he added, “one wonders about the high rate of catheterization relative to percutaneous coronary intervention, [which] was also seen in inappropriate shocks, where one generally would not suspect ischemia or an acute coronary syndrome as a cause. I can’t use this as a template to say this is how you should or shouldn’t care for these patients, but many of these patients—I think it is safe to say—would never have received all of that healthcare if they never got the inappropriate shock.”

The more important message, Turakhia said, is that clinicians need to be more proactive about ensuring that the programming of devices is kept up to date.

“The newer implanted devices typically have out-of-the-box settings that reflect contemporary practice, but it’s really making sure we reprogram patients with existing devices when the evidence changes during the course of their device implant period,” he said. “We’ve spent the last 10-plus years thinking about making sure that the right patients are getting the ICDs. Now that we have trials like MADIT-RIT and data like this, we need to shift our efforts to focus on the quality of the ICD programming [so it’s] both personalized and evidence-based.”

Resource Use Similar for Appropriate, Inappropriate Shocks

Although ICDs improve survival in patients at risk for sudden death, shocks have been associated with higher long-term risks of morbidity and mortality. Recent studies—including the MADIT-RIT trial—have shown that device programming to reduce shocks improves the outlook of patients. However, healthcare resource use related to shocks has not been examined in detail in prior studies.

For this analysis, the investigators linked ICD remote monitoring data with information on Medicare supplemental claims from 10,266 patients implanted with ICDs or cardiac resynchronization therapy-defibrillator devices between 2008 and 2010. The study focused on 963 patients (9.4%) who had 1,885 shock events (56% appropriate, 38% inappropriate, and 6% indeterminate).

Patients with a shock-related hospitalization within 7 days of the event often underwent diagnostic or invasive procedures. Aside from cardiac catheterizations, patients also underwent ECGs (85%), chest x-rays (76%), echocardiography (59%), electrophysiology studies or ablation (34%), stress testing (16%), and lead revision (11%).

Healthcare use also was prevalent among patients who were not admitted and included device interrogations (76%), ECGs (73%), ambulance transportation (61%), emergency room visits (46%), and chest X-rays (41%).

Across all shock events, mean and median expenditures were $5,887 and $901, respectively, with no significant differences between appropriate and inappropriate shocks.

‘More Reasoned Approach’ Needed

Commenting for TCTMD, Peter Kowey, MD (Lankenau Heart Institute, Wynnewood, PA), said that “this is an issue that is extremely important in our community because more people are getting defibrillators and an irreducible number of them, no matter what you do, are going to get shocked.”

He noted that in addition to the economic impact of shocks demonstrated by the study, the events are tied to psychological and physical consequences, as well.

Like Turakhia, he pointed out that the analysis cannot show whether the measures taken after a shock were appropriate or inappropriate. “It’s just that we’re concerned because of the volume and some of the data that look like there’s really not much that happens that’s different after all the testing that gets done,” he explained. “That’s the thing that makes you think that perhaps there’s some procedures that are being done unnecessarily.”

That can have important economic implications “that we need to pay some attention to,” Kowey said. “Doctors have to be much more careful about discriminating appropriate versus inappropriate device therapy and then [use] a much more reasoned approach to evaluating the patients, rather than just sort of plunging headlong into invasive procedures or more aggressive evaluations.”

In an accompanying editorial, Ryan Borne, MD, and Pamela Peterson, MD (University of Colorado Anschutz Medical Campus, Aurora, CO), say that the study indicates areas of potential overuse of care but also underuse, citing the fact that more than half of shocks were not associated with any healthcare use in the first week.

“Thus, there is a need and an opportunity to improve health for patients receiving ICD shocks and to increase value,” they write. “As technology advances, understanding the downstream use of healthcare and the effects of that healthcare on outcomes is an important aspect of providing high-value quality care.”