HRS Doesn’t Miss a Beat with Cutting-edge Trials

The Heart Rhythm Society focused on the latest developments in electrophysiology and the management of patients with rhythm disorders and heart failure at its 2015 meeting on May 13-16 in Boston. The event included 12 late-breaking clinical trials.

Remote monitoring leads to cost savings, fewer hospitalizations

Patients who had remote monitoring in their implantable electronic cardiac devices had lower all-cause hospitalization costs and recurrent hospitalizations compared with patients without remote monitoring capabilities, according to a large, retrospective, cohort study.

After adjusting for patients’ age, sex and geographic location, there was an 18 percent reduction in all-cause hospitalization associated with the use of remote monitoring. The benefit was consistent across all devices from all manufacturers, including patients with pacemakers who did not have high-voltage devices.

Researchers also found that remote monitoring was associated with a $3,700 reduction in costs per patient year. They estimated that for every 100,000 patient-years, the use of remote monitoring was associated with 9,810 fewer hospitalizations, 119,000 fewer days in the hospital and more than $370,000 savings in hospital costs.

“We learned that in routine clinical practice in this nationwide sample, we saw that remote monitoring was associated with improved clinical outcomes,” says presenter Jonathan P. Piccini, MD, of Duke University Medical Center in Durham, N.C. “And those improved clinical outcomes were associated with significant decreases in healthcare expenditures for all-cause hospitalization.”

The researchers analyzed remote monitoring use in adult patients who received pacemakers, implantable cardioverter-defibrillators (ICDs) or cardiac resynchronization therapy (CRT) devices in the U.S. between April 1, 2008 and March 31, 2013. Of the 92,566 patients who met the inclusion criteria, 34,259 had remote monitoring and 58,307 did not have remote monitoring; 59 percent of patients received pacemakers, 30 percent ICDs and 11 percent CRT devices. Remote monitoring was used in 29 percent of the pacemakers, 49 percent of the ICDs and 51 percent of the CRT devices.

Among patients who were hospitalized, the mean length of stay was 5.3 days in the remote monitoring group and 8.1 days in the group that did not have remote monitoring. The difference was statistically significant.

The magnitude of the lower risk of hospitalization was greater in ICD recipients and patients with CRT devices compared with those who received pacemakers.

There was a 43 percent reduction in all-cause hospitalization costs in ICD recipients and a 45 percent cost reduction in CRT device recipients, which Piccini says was associated with an $11,000 reduction in healthcare expenditures per year.

In patients with a prior diagnosis of heart failure, use of remote monitoring was associated with a 31 percent reduction in costs and a statistically significant decrease in length of hospital stay of 2.5 days.

No adverse outcomes in patients with ICD system undergoing MRIs

Patients with the Iforia ProMRI implantable cardiac device (ICD) system had no adverse outcomes related to the device and no significant changes to pacing or sensing parameters after undergoing a thoracic spine or cardiac MRI, according to a multicenter, nonrandomized trial.

All episodes of life-threatening ventricular arrhythmias were appropriately detected and treated. The MRI had no impact on the ICD’s main function of detecting and treating arrhythmias.

Researcher Khaled Awad, MD, presented results of the study during a late-breaking clinical trials session at Heart Rhythm 2015. Biotronik, the device’s manufacturer, funded the study.

No ICD systems currently have an FDA labeling indicating they are safe for use in MRIs, according to  Awad, of the University of Alabama at Birmingham. Patients with ICDs typically do not undergo an MRI because of potential adverse outcomes, including interactions between the ICD system and the electromagnetic fields generated by the MRI machine. However, some pacemakers are designed to work with MRIs, although the successful interaction between ICDs and MRIs is unknown. Biotronik, which funded the study, initiated the trials to investigate the safety and efficacy of ICD platforms in MRIs.

Of the 170 patients who were provisionally enrolled at 39 centers in the U.S., 154 met the eligibility criteria. All but six patients underwent a cardiac or thoracic MRI with a standard 1.5T scanner.

“The design of the protocol was aimed at stressing the device and the whole system as much as possible and increasing the magnitude of the magnetic fields to probably the highest levels that you could encounter in a clinical scan,” Awad says.

The researchers found there were 43 adverse events, but most were not serious and none were related to the ICD or MRI. The most common events were incidental MRI findings and heart failure exacerbation.

Baroreflex activation therapy improves quality of life in heart failure patients

A novel approach known as baroreflex activation therapy (BAT) led to a 30 percent improvement in New York Heart Association (NYHA) classification and an increase in quality of life among patients with heart failure and reduced ejection fraction who had failed previous therapies.

There was also a mean 60 to 70 meter increase six-minute hall walk and a mean 12-point increase in the quality of life score on the Minnesota Living with Heart Failure questionnaire.

“A [change] of 12 points is enormous,” says researcher Michael Zile, MD, of the Medical University of South Carolina in Charleston, S.C. “For most pharmacologic therapies that are used in reduced ejection fraction heart failure, we have a decrease of five points. In the original CRT [cardiac resynchronization therapy] studies, it was a decrease of 10 points. This is clearly even larger than that, and that’s on top of pre-existing therapies.”

The researchers randomized patients to receive BAT plus optimal medical and device therapy or optimal medical and device therapy alone. Patients had left ventricular ejection fraction less than 35 percent and a diminished six-minute hall walk of between 120 and 400 meters. They were also all NYHA Class III. 

“These are patients who have symptoms with activities of daily living in which their activity level is markedly diminished and impacted by the presence of the heart failure,” Zile says.

Of the patients, 95 received CRT and 45 did not receive CRT. The benefit of BAT was larger in patients who had not undergone CRT compared with patients who had CRT, according to Zile.

“We don’t mean to suggest that CRT patients aren’t responsive,” he says. “We are just noting the fact that the no-CRT group seemed to have a more pronounced impact.”

BAT consisted of a 2 mm electrode surgically implanted on the carotid sinus and connected to a surgically implanted subcutaneous power unit. The device was implanted before patients left the hospital. They then returned at two- to six-week intervals to have the therapy increased in strength until they reach a maximum threshold for the therapy, according to Zile.

“This particular therapy is different from all other neuromodulatory therapies because it sends an afferent signal from the carotid sinus to the brain, in which there’s an integrated response from the brain back down to the body,” Zile says. “There’s an integrated effect of a reduction in sympathetic tone and an increase in parasympathetic tone, which means it targets all neuromodulatory abnormalities within this clinical syndrome of heart failure.”

The FDA recently approved the initiation of a large, prospective, randomized trial to confirm the results of this study.

“This represents a therapy which can be applied to those patients in which you’ve exhausted all other therapies,” Zile says. “And it can be applied to those patients who are not candidates for CRT. It will fit into a unique position of therapy for this group of symptomatic patients.”

Safety and efficacy of VGLB procedure similar to RF ablation

Preliminary results of a randomized trial found the HeartLight visually-guided laser balloon (VGLB) system was as safe and effective as irrigated radiofrequency ablation in patients with paroxysmal atrial fibrillation (PAF).

The study randomized 353 patients at 21 sites in the U.S. At 12 months, 61.1 percent of patients in the VGLB group and 61.7 percent of patients in the radiofrequency ablation group met the primary efficacy endpoint of freedom from AF at 12 months. Primary adverse events were found in 11.8 percent of patients in the VGLB group and 14.5 percent of patients in the radiofrequency ablation group. After excluding cardioversions, the clinical primary adverse event rates were 5.3 percent and 6.4 percent, respectively.

The mean procedure time was 236 minutes with VGLB and 193 minutes with radiofrequency ablation, while the mean ablation time was 173.8 minutes and 151.2 minutes, respectively. Single procedure success was found in 61.1 percent of patients in each group.

The operators were experienced with radiofrequency ablation, but they did not have much experience with VGLB. Before the study, only 23 percent of operators had performed more than five VGLB procedures and 7 percent had performed more than 10 such procedures. None of the operators had performed more than 100 VGLB procedures.

“With experience, you have improvements in efficacy and improvements in safety,” says presenter Vivek Y. Reddy, MD, of Mount Sinai School of Medicine in New York. “In fact, one study suggests it’s after you do 100 procedures that your success rate really starts to increase into the 80-85 percent success rate.

"Will that happen with the laser balloon? I would guess yes. Of course, we need more data to really prove that.”

The HeartLight VGLB system (CardioFocus) is an investigational device and is not FDA-approved. CardioFocus funded the trial.

Early Micra TPS analysis shows 100% success in implantation

All 140 patients analyzed and enrolled in a single-arm, multicenter trial had successful implants with the Micra Transcatheter Pacing System (TPS), a miniaturized leadless pacemaker that is not yet approved in the U.S.

After a mean follow-up of 1.9 months, all but one of the patients were alive and remained in the study. The one death was unrelated to the procedure. Serious adverse events occurred in 5.7 percent of patients, and two patients required hospitalization.

There were no unforeseen events, no device telemetry issues, no dislodgements, no infections and no reoperations.

“I’ve been involved in pacing now for 30 years, and I’ve never seen such results,” says researcher Philippe Ritter, MD, of Hopital Haut-Leveque in Pessac, France, adding that this study was the first in-human experience of a miniaturized leadless pacemaker.

This analysis was the first of three prespecified analyses and occurred after the first 60 patients passed their three-month follow-up.

The mean implant time was 37 minutes. During the implant, 59 percent of the procedures were successful after one deployment, 81 percent were successful within two deployments and 96 percent were successful within four deployments.

The Micra TPS’s volume is 93 percent less than a conventional system, while its mass is 10 times less. The battery service life of the Micra TPS (Medtronic) is 9.6 years compared with 10.3 years for a conventional system.

Two other analyses are scheduled: the primary objective analysis will occur after the first 300 patients passed their three-month follow-up, while a long-term performance analysis is planned for after the first 700 patients are followed for 12 months.