Alert Tones Are Frequently Inaudible among Patients with Implantable Cardioverter-Defibrillators

Implantable Cardiovascular Devices: Current and Emerging Technologies for Remote Heart Failure Monitoring

Heart failure remains a substantial socioeconomic burden to our health care system. With the aging of the population, the incidence is expected to rise in the ensuing years. Standard heart failure management strategies have failed to reduce hospitalizations and mortality. In patients with heart failure, remote hemodynamic monitoring with implantable devices provides essential data, which can be used in unison with standard patient management to reduce heart failure hospitalizations. This review will chronicle the important clinical trials of various implantable devices and describe the emerging technologies in remote heart failure management. Cardiovascular implantable electronic devices, namely implanted cardioverter-defibrillator and cardiac resynchronization therapy devices with defibrillator, have evolved beyond sole resynchronization and currently can deliver real-time cardiac hemodynamics. Clinical data regarding hemodynamic monitoring with implanted cardioverter-defibrillator and cardiac resynchronization therapy devices with defibrillator have not consistently demonstrated a reduction in heart failure or mortality benefit. However, there is promise in the future with the application of multiparameter diagnostic algorithms with these devices. The most efficacious implantable device has been the pulmonary artery pressure sensor, CardioMEMS. This device has been proven to be safe and shown to reduce heart failure hospitalizations. Moreover, multiple newly developed devices are currently under investigation after successful first-in-man studies.

The AngelMed Guardian® System in the Detection of Coronary Artery Occlusion: Current Perspectives

Total ischemic time, which specifies the time from the onset of chest pain to initiation of reperfusion during percutaneous coronary intervention, consists of two intervals: symptom to door time and door to balloon time. A door to balloon time of 90 mins or less has become a quality-of-care metric in the management of ST elevation myocardial infarction (STEMI). While national efforts made by the American College of Cardiology (ACC) and American Heart Association (AHA) have curtailed in-hospital door to balloon time over the years, a reduction in pre-hospital symptoms to door time presents a challenge in modern interventional Cardiology. Early and complete revascularization has been associated with improved clinical outcomes in MI and strategies that may help reduce symptom to door time, and thus the total ischemic time, are crucial. Rapidly evolving ST-segment changes commonly develop prior to ischemia-related symptom onset, and are detectable even in patients with clinically unrecognized silent MIs. Therefore, a highly intelligent ischemia detection system that alerts patients of ST segment deviation may allow for rapid identification of acute coronary occlusion. The AngelMed Guardian^® System is a cardiac activity monitoring and alerting system designed for rapid identification of intracardiac ST-segment changes among patients at a high risk for recurrent ACS events. This article reviews the clinical studies evaluating the design, safety and efficacy of the AngelMed Guardian System and discusses the clinical implications of the device.

Investigation of the Utility of the Audible Alert in Recent Generation Medtronic Implantable Cardioverter Defibrillators

BACKGROUND

Medtronic implantable cardioverter defibrillators (ICDs; Medtronic Inc., Mounds View, MN, USA) are equipped with Patient Alert™, a feature in which the ICD generator emits a series of audible tones to notify patients of possible system malfunction. A prior study of this issue revealed that only 50% of patients with older Medtronic devices were able to hear alerts. More recently, Medtronic has incorporated modifications to the alert. Therefore, we studied how frequently alert tones emitted by the current generation of Medtronic ICDs are audible by patients.

METHODS

A series of patients were evaluated in an outpatient ICD clinic. Alert tones were demonstrated using a device programmer in a quiet room and in the presence of low-level background noise. Patients reported whether they heard the tones, and they completed questionnaires regarding the tones.

RESULTS

The total sample size was 100 patients, 81 male, who ranged from 29 years to 94 years of age (mean age 72.1 ± 11.8). Among the study subjects, 46% were older than 75 years, 41% were between 55 years and 75 years, and 13% were younger than 55 years. In the absence of background noise, 94% of patients were able to hear both alerts, 1% heard only one alert, and 5% heard neither. In the presence of background noise, 88% of patients heard both the alerts, 7% heard only one alert, and 5% heard neither alerts.

CONCLUSIONS

Our results demonstrate that alert tones in recent generation Medtronic ICDs have improved audibility, compared to prior published data, among a large outpatient ICD population.

Remote monitoring of heart failure patients

"The Teledactyl (Tele, far; Dactyl, finger--from the Greek) is a future instrument by which it will be possible for us to 'feel at a distance.' This idea is not at all impossible, for the instrument can be built today with means available right now. It is simply the well known telautograph, translated into radio terms, with additional refinements. The doctor of the future, by means of this instrument, will be able to feel his patient, as it were, at a distance...The doctor manipulates his controls, which are then manipulated at the patient's room in exactly the same manner. The doctor sees what is going on in the patient's room by means of a television screen." -Hugo Gernsback, Science and Invention Magazine, February 1925 Heart failure continues to be a major burden on our health care system. As the number of patients with heart failure increases, the cost of hospitalization alone is contributing significantly to the overall cost of this disease. Readmission rate and hospital length of stay are emerging as quality markers of heart failure care along with reimbursement policies that force hospitals to optimize these outcomes. Apart from maintaining quality assurance, the disease process of heart failure per-se requires demanding and close attention to vitals, diet, and medication compliance to prevent acute decompensation episodes. Remote patient monitoring is morphing into a key disease management strategy to optimize care for heart failure. Innovative implantable technologies to monitor intracardiac hemodynamics also are evolving, which potentially could offer better and substantial parameters to monitor.

Clinical outcomes in patients with implantable cardioverter defibrillators and Sprint Fidelis leads

OBJECTIVE

The performances of implantable cardioverter defibrillators and leads are important issues for healthcare providers and patients. In 2007 Sprint Fidelis leads were found to be associated with an increased failure rate and so the purpose of the study was to evaluate long-term mortality and clinical outcomes in patients implanted with Sprint Fidelis leads compared with Sprint Quattro leads.

DESIGN, SETTING, PATIENTS

508 patients with Sprint Fidelis leads and 468 with Sprint Quattro leads were prospectively followed in 12 Italian cardiology centres.

MAIN OUTCOME MEASURES

Information on hospitalisations and other clinical events were collected during scheduled and unscheduled hospital visits. Deaths were identified from medical records or via phone contacts with patients' family members or through the National Office of Vital Statistics.

RESULTS

Over a mean follow-up of 27±18 months 141 deaths occurred in the overall population. No death was observed in patients with diagnosed failing lead. Kaplan-Meier patient survival differed between the two lead groups (80±2% in Fidelis leads vs 70±4% in the Sprint Quattro leads at 4 years, p=0.002). Multivariate analyses showed that mortality was neither associated with lead type nor with diagnosed failed lead. The annual rate of lead failure was 1.8% patient-year for Fidelis leads and 0.2% for the Sprint Quattro leads.

CONCLUSIONS

In our multicentre research, the clinical outcomes of patients with Fidelis leads differed from those of patients with Sprint Quattro leads. Nevertheless, neither mortality nor the combined endpoint of mortality and heart failure hospitalisations was associated with the lead type. http://clinicaltrials.gov/ct2/show/NCT01007474.

Remote monitoring reduces healthcare use and improves quality of care in heart failure patients with implantable defibrillators: the evolution of management strategies of heart failure patients with implantable defibrillators (EVOLVO) study

BACKGROUND

Heart failure patients with implantable cardioverter-defibrillators (ICDs) or an ICD for resynchronization therapy often visit the hospital for unscheduled examinations, placing a great burden on healthcare providers. We hypothesized that Internet-based remote interrogation systems could reduce emergency healthcare visits.

METHODS AND RESULTS

This multicenter randomized trial involving 200 patients compared remote monitoring with standard patient management consisting of scheduled visits and patient response to audible ICD alerts. The primary end point was the rate of emergency department or urgent in-office visits for heart failure, arrhythmias, or ICD-related events. Over 16 months, such visits were 35% less frequent in the remote arm (75 versus 117; incidence density, 0.59 versus 0.93 events per year; P=0.005). A 21% difference was observed in the rates of total healthcare visits for heart failure, arrhythmias, or ICD-related events (4.40 versus 5.74 events per year; P<0.001). The time from an ICD alert condition to review of the data was reduced from 24.8 days in the standard arm to 1.4 days in the remote arm (P<0.001). The patients' clinical status, as measured by the Clinical Composite Score, was similar in the 2 groups, whereas a more favorable change in quality of life (Minnesota Living With Heart Failure Questionnaire) was observed from the baseline to the 16th month in the remote arm (P=0.026).

CONCLUSIONS

Remote monitoring reduces emergency department/urgent in-office visits and, in general, total healthcare use in patients with ICD or defibrillators for resynchronization therapy. Compared with standard follow-up through in-office visits and audible ICD alerts, remote monitoring results in increased efficiency for healthcare providers and improved quality of care for patients.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00873899.

“This is your heart speaking. Call 911.”

Early warning for heart attacks could save many lives. We conducted three studies to design and evaluate multimodal alarms and patient training for an implanted heart attack detector. An implanted device provided vibrotactile alarms subcutaneously, and a pager-like device provided auditory and visual alarms. Temporal alarm patterns connoted an urgent emergency alarm (“Call 911”) and a less urgent alarm (“See your doctor”). In the third, clinical, study, most patients (94%) correctly responded to the alarms at 1, 3, and 6 months after device implantation. Subcutaneous vibrotactile alarms show great potential for use in critical medical applications.

ISHNE/EHRA expert consensus on remote monitoring of cardiovascular implantable electronic devices (CIEDs)

We are in the midst of a rapidly evolving era of technology-assisted medicine. The field of telemedicine provides the opportunity for highly individualized medical management in a way that has never been possible before. Evolving medical technologies using cardiac implantable devices with capabilities for remote monitoring permit evaluation of multiple parameters of cardiovascular physiology and risk, including cardiac rhythm, device function, blood pressure values, the presence of myocardial ischaemia, and the degree of compensation of congestive heart failure. Cardiac risk, device status, and response to therapies can now be assessed with these electronic systems of detection and reporting. This document reflects the extensive experience from investigators and innovators around the world who are shaping the evolution of this rapidly expanding field, focusing in particular on implantable pacemakers, implantable cardioverter defibrillators, devices for cardiac resynchronization therapy (both with and without defibrillation properties), loop recorders, and hemodynamic monitoring devices. This document covers the basic methodologies, guidelines for their use, experience with existing applications, and the legal and reimbursement aspects associated with their use. To adequately cover this important emerging topic, the International Society for Holter and Noninvasive Electrocardiology and the European Heart Rhythm Association combined their expertise in this field. We hope that the development of this field can contribute to improve care of our cardiovascular patients.