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New technologies advance treatment options for patients with arrhythmia disorders, HF
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The pace of technology and research on the treatment of arrhythmia disorders and HF continues to advance, giving patients access to new options that were not available even a short time ago.
Specifically, new developments in the use of remote monitoring for patients with implantable cardiac devices have advanced to the point that it is now documented that remote monitoring is associated with reduced rates of mortality and hospitalization, as well as lower health care costs. The Heart Rhythm Society recently issued a recommendation that remote monitoring be the standard of care for all patients with implantable cardiac devices.
“The data are now quite clear that remote monitoring improves outcomes and even reduces mortality,” Michael R. Gold, MD, PhD, FHRS, FACC, chief of cardiology and Michael E. Assey Professor at Medical University of South Carolina, Charleston, told Cardiology Today. “Although we don’t yet fully understand all the reasons for these findings, the consistency of data clearly indicate that remote monitoring is beneficial for patients and reduces health care costs.”
Progress has also been made in the field of imaging compatibility with implantable cardiac devices. Two recent studies demonstrated the safety and effectiveness of MRI-compatible implantable cardioverter defibrillators. In September, the technology assessed in one of those studies, the Evera MRI SureScan ICD system (Medtronic), became the first ICD system approved by the FDA with an indication for use with MRI scans.
Photo: Shawn Rocco/Duke Medicine; printed with permission.
“We are seeing important advancements in ICD technology,” Andrea M. Russo, MD, FACC, FHRS, professor of medicine at Cooper Medical School of Rowan University, director of cardiac electrophysiology and arrhythmia services, and director of the electrophysiology fellowship at Cooper University Hospital, Camden, New Jersey, said in an interview. “Many patients are getting devices at a younger age and will likely require an MRI scan sometime during their lifetime. Having a defibrillator and leads in place that are MRI-compatible is essential, so we can give patients the best diagnostic test that they might need in the future.”
Evidence for remote monitoring
In May, the HRS released an expert consensus statement giving a class I, level of evidence A recommendation to conducting remote monitoring and interrogation combined with at least one annual in-person evaluation instead of relying on in-person examinations only. It gave a similarly strong recommendation for offering all patients with implantable cardiac devices remote monitoring as part of standard follow-up management.
The panel also strongly recommended that remote monitoring be performed to check on lead function and battery conservation and also stated that it is useful for detecting and quantifying atrial fibrillation early. Further, the panel noted that there is adequate evidence to conclude that remote monitoring can help reduce inappropriate ICD shocks.
Trials “consistently show meaningful patient benefits from the early detection capabilities of automatic [remote monitoring],” writing group chair David Slotwiner, MD, FHRS, FACC, and colleagues wrote in the consensus statement. “Incorporation of [remote monitoring] into a follow-up practice, integrating this technology with a modified frequency of the conventional [in-person evaluation] ensures greater patient retention and improves adherence to scheduled evaluations.”
One such study of 262,564 patients (mean age, 71 years; 65% men) implanted with any St. Jude Medical cardiac device found that patients with remote monitoring had significantly higher survival rates than those without remote monitoring, regardless of device type (HR = 1.81; 95% CI, 1.77-1.86), and that the effect was especially pronounced in those with high adherence to remote monitoring (adjusted HR = 2.1; 95% CI, 2.04-2.16). For patients with pacemakers, those with high utilization of remote monitoring had a better survival rate than those with low or no utilization, and those with low utilization had a better survival rate than those with no utilization, Suneet Mittal, MD, FACC, FHRS, director of electrophysiology at the Valley Health System of New York and New Jersey, and colleagues reported.
In another study by Jonathan P. Piccini, MD, MHS, FACC, FAHA, FHRS, associate professor of medicine at Duke University Medical Center, and colleagues, among 92,566 patients aged 21 years or older (mean age, 72 years; 63% men) implanted with a pacemaker, ICD or CRT device included in the MarketScan Commercial and Medicare Supplemental claims databases, remote monitoring was associated with lower all-cause hospitalization costs per patient-year, shorter mean length of stay (5.3 days vs. 8.1 days; P < .001) and fewer hospitalization events per patient-year (adjusted HR for all = 0.82; 95% CI, 0.8-0.84).
Value and benefits
Experts interviewed by Cardiology Today agreed that implantable cardiac devices should be equipped with remote monitoring and all patients should be encouraged to have the remote monitoring features on their devices activated.
“Remote monitoring allows early detection of arrhythmias, the most frequent of which is AF. When identified early, it allows initiation of anticoagulation to reduce stroke rates or treatment of the AF if it is symptomatic,” Gold, president-elect of the HRS, told Cardiology Today. “Remote monitoring can also be used to identify pending lead failures or problems with devices. Knowing about these problems right away is better than having a patient show up for a quarterly or semiannual check where it may only be discovered at that point. There are other features in devices that may help identify pending HF exacerbations.”
Gold also noted that having patients more engaged in their care with remote monitoring may be beneficial for his or her overall care.
To date, investigators have not been able to fully explain the mechanisms behind the benefits observed in studies of remote monitoring.
“The benefits appear to come through multiple different mechanisms,” Piccini said. “This is very much an active ongoing area of research. We have many hypotheses and hints, but this is something we continue to learn more and more about.”
One part of the explanation, Russo said, is that patients with remote monitoring are less likely to get inappropriate shocks than patients without remote monitoring.
“The most powerful and consistent data from all the studies show that we can reduce inappropriate shocks, and some studies also demonstrate reduced mortality. We can only speculate on reasons for improved outcomes, which may be related to earlier detection of either arrhythmias or inappropriate therapy, device diagnostics providing earlier notification of impedance changes or increased frequency of right ventricular pacing that may worsen HF, or just better overall adherence to follow-up,” she said. “Enhanced communication with the health care team in between office visits may expedite appropriate clinical interventions.”
According to Mittal, “Most of the value comes from the stored diagnostics, to be able to understand when someone may be in AF, for which you can initiate therapy; recognizing when patients may be pacing too much or too little; and understanding their HF parameters. It stands to reason that having that knowledge of that, being alerted to that and intervening in that is probably a large contributor to the value proposition.”
Fortunately, he said, “as the value of remote monitoring has become more obvious, there are more data and better formatting of the data being done by industry to make it easier, simpler and better to interpret.”
Underutilization of services
Despite the well-documented benefits of remote monitoring, a substantial percentage of patients with implantable cardiac devices do not use it. Increasing this proportion will take not only further advancements in the technology but changes in patient attitude and physician behavior, experts told Cardiology Today.
According to data from studies sponsored by Boston Scientific, “whether a patient is or is not enrolled in remote monitoring is largely dependent on the institution at which the device implantation is taking place, which suggests that it’s the local perceptions of the value of remote monitoring that are dictating whether patients are being enrolled or not,” Mittal said.
Patients with a device without wireless capability may find it cumbersome to transmit their data over an analog phone line, he said. “Many patients don’t have analog phone lines, and going to a cellular network might incur an out-of-pocket expense for them.”
More of a factor, Mittal said, is that “a lot of patients just don’t understand what the value is. Many continue to believe that if they come into the office every 3 months, they can accomplish the exact same thing and see their doctor. The onus is on us to try to teach patients what the value of daily remote monitoring is. Being in the office every 3 months does not equal being monitored daily for those 3 months.”
Including wireless capability on all devices will help, but the most important future developments will be “improvements in our understanding of how to optimally implement” remote monitoring, Piccini said.
Evidence for MRI-compatible ICDs
Another recent technological breakthrough is the advent of MRI-compatible ICDs. MRI-compatible pacemakers have existed for years, but MRI was generally considered off-limits for patients with ICDs.
New data reflect numerous advancements in this area. The Evera MRI study of Medtronic’s MRI-compatible ICD, conducted by Gold and colleagues, included 275 patients (mean age, 60 years; 76% men; 74% with primary prevention indication) with a de novo indication for an ICD. Patients were randomly assigned to a full-body MRI at 1.5 Tesla (T) or no MRI.
All patients met the primary safety endpoint of greater than 90% freedom from MRI-related complications 30 days after the scan and sustained tachyarrhythmia occurring during MRI. Most patients met the primary efficacy endpoints: All patients from the MRI group demonstrated a 0.5-V or less increase in ventricular pacing capture threshold vs. 98.2% of controls (P for noninferiority < .0001), whereas 99.3% of the MRI group and 98.8% of controls had a 50% or less decrease in R-wave amplitude (P for noninferiority = .0001).
Based on results of that study, published in the Journal of the American College of Cardiology and presented at the HRS Scientific Sessions in May, the FDA in September approved the Evera MRI system, the agency’s first approval of an MRI-compatible ICD.
In the ProMRI study, researchers found that another MRI-compatible system, Iforia ProMRI (Biotronik), was safe and effective in 170 patients (mean age, 60 years; 77% men; 22% with ICD indication for secondary prevention) undergoing a cardiac or thoracic spine MRI at 1.5 T.
The rate of freedom from serious adverse device events was 100% (P < .001), whereas freedom from ventricular capture threshold increase greater than 0.5 V at 1 month was 100% (P < .001) and freedom from decrease in R-wave sensing was 99.3% (P < .001), according to findings published in Heart Rhythm and presented at the HRS Scientific Sessions. The one patient who did not meet the endpoint did not undergo an MRI because of claustrophobia, researchers reported.
New standard of care
These advances can be helpful to patients because, currently, most radiology suites will not perform MRI scans on those with ICDs, although many can be programmed to almost eliminate the risk for MRI-related complications, experts said.
“Obviously, with time, all devices will be MRI-compatible,” Mittal said. “The issue of MRI compatibility has been a little less acute because we now know from large-center studies that, in a pinch, modern defibrillators and pacemakers can be placed in an MRI environment with little risk to the patient or the devices. Having said that, it will be good to have MRI-approved products because when it comes to protocols in radiology suites, it does help quite a bit. When you look at the universe of patients who undergo an MRI, those with an implantable cardiac device is still a vanishingly small number.”
Eventually, MRI-compatible devices will become the standard of care, Gold said.
“Early on, this will be limited to certain devices from certain companies, so there may be other reasons why not all patients will get them, but certainly in the not-too-distant future, MR compatibility will be ubiquitous and it will become the standard,” he said. “For instance, in Japan, where multiple MR-compatible devices have been approved, greater than 80% of all new ICDs are MR devices.”
Whether all patients who get an ICD should get an MRI-compatible device “is a very hard question to answer because the landscape is changing very quickly,” Piccini said. “It’s important to keep in mind because there are some patients who absolutely cannot have these studies, including patients with abandoned leads and, some would advocate, patients who are completely dependent on their device because they have no underlying rhythm.”
However, he said he anticipates that “in a very short time, all devices will be MRI-conditional, either because they’ve gone through clinical studies prospectively or because an increasing amount of evidence will likely bear out that as long as it is performed under the right conditions, it can be done safely.”
As an example of the latter, results of the MagnaSafe registry of 1,000 patients with pacemakers and 500 patients with ICDs, presented at the 2014 American Heart Association Scientific Sessions, indicated that even standard devices can withstand MRI scans, provided that they are programmed correctly and patients are screened appropriately.
Researchers reported no deaths, lead failures or loss of pacemaker capture during the study, and no clinically significant changes in battery voltage, lead threshold, P-wave amplitude, R-wave amplitude or high-voltage impedance. One ICD failed because of a protocol error and six patients experienced AF during the scan, although only one was new-onset AF, which resolved within 48 hours, they found.
Developments abound
Technological development continues, and there are several new systems that are attracting attention.
One, according to Piccini, is a wireless left ventricular endocardial pacing system for patients with HF. An ultrasound-based wireless cardiac stimulation system (WiCS-LV, EBR Systems), it includes a 9-mm leadless pacing electrode activated by a submuscular ultrasonic transmitter synchronized to a right ventricular pacing pulse of a standard pacemaker or ICD. In the SELECT-LV pilot study, patients who underwent the implant had a reduction in mean QRS and a seven-point increase in ejection fraction, although there were some safety issues, according to findings presented at the HRS Scientific Sessions.
“Developing alternative means of ventricular pacing and other technologies to improve response rates are really important,” Piccini said.
He also cited numerous recent advances in ablation technology, including electroporation, use of laser balloons and new iterations of ablation catheters with contact force sensors.
Gold agreed that ablation technology has progressed impressively. “We continue to make advances in therapies for AF with contact force catheters that appear to have more durable lesions for pulmonary vein isolations,” he said. “Cryoballoons are become much more commonly used for pulmonary vein isolation for paroxysmal AF. It is a simpler, quicker procedure which should reduce complication rates.”
Another helpful technology, Russo said, is an implantable wireless device with remote monitoring for patients with HF (CardioMEMS HF System, CardioMEMS).
“A lot of these patients won’t have implantable devices that can also assess volume status or measure thoracic impedance,” she said. “For patients with HF that don’t have an ICD or pacemaker in place, wireless pulmonary artery pressure monitoring technology reduces rehospitalization from decompensated HF, hopefully reducing the cost. This may be particularly useful for patients who have HF with preserved ejection fraction, as medical therapy to reduce hospitalization is currently limited in this group.”
Although new innovations will continue to change the shape of how patients with arrhythmia disorders and HF are cared for, improving and integrating current innovations is just as important, Piccini said. “With any new advance in care or any new clinical study that shows us there may be a better way to deliver care, that’s always just the very first step,” he said. “While there are some new technologies coming down the road, what’s even more important than that is taking care of the interventions we already have with us.” – by Erik Swain
- References:
- Awad K, et al. Heart Rhythm. 2015;doi:10.1016/j.hrthm.2015.06.002.
- Gold MR, et al. J Am Coll Cardiol. 2015;doi:10.1016/j.jacc.2015.04.047.
- Piccini JP, et al. Abstract LBCT01-01. Presented at: Heart Rhythm Society Annual Scientific Sessions; May 13-16, 2015; Boston.
- Russo RJ, et al. CS.04: Trials and Cardiovascular Registries. Presented at: American Heart Association Scientific Sessions; Nov. 15-19, 2014; Chicago.
- Slotwiner D, et al. Heart Rhythm. 2015;doi:10.1016/j.hrthm.2015.05.008.
- Varma N, et al. J Am Coll Cardiol. 2015;doi:10.1016/j.jacc.2015.04.033.
- For more information:
- Michael R. Gold, MD, PhD, FHRS, FACC, can be reached at 25 Courtenay Drive, Charleston, SC 29425; email: goldmr@musc.edu.
- Suneet Mittal, MD, FACC, FHRS, can be reached at 223 N. Van Dien Ave., Ridgewood, NJ 07450; email: mittsu@valleyhealth.edu.
- Jonathan P. Piccini, MD, MHS, FACC, FAHA, FHRS, can be reached at jonathan.piccini@duke.edu.
- Andrea M. Russo, MD, FACC, FHRS, can be reached at Cooper University Hospital, Dorrance Building, 4th Floor, 1 Cooper Plaza, Camden, NJ 08103; email: russo-andrea@cooperhealth.edu.
Disclosures: Gold reports consulting for Boston Scientific, Medtronic and St. Jude Medical. Mittal reports consulting for Boston Scientific, Medtronic, Sorin and St. Jude Medical. Piccini reports receiving research grants from Boston Scientific, Johnson & Johnson and St. Jude Medical and consulting for Medtronic and Spectranetics. Russo reports receiving research grants from Boston Scientific and Medtronic; consulting for Boston Scientific; and receiving speaking honoraria from Boston Scientific, Medtronic and St. Jude Medical.