Safety and performance of MR-conditional pacing systems with automated MRI mode at 1.5 and 3 Tesla

OBJECTIVES

To evaluate at 1.5 and 3 T MRI the safety and performance of trademarked ENO®, TEO®, or OTO® pacing systems with automated MRI Mode and the image quality of non-enhanced MR examinations.

METHODS

A total of 267 implanted patients underwent MRI examination (brain, cardiac, shoulder, cervical spine) at 1.5 (n = 126) or 3 T (n = 141). MRI-related device complications, lead electrical performances stability at 1-month post-MRI, proper functioning of the automated MRI mode and image quality were evaluated.

RESULTS

Freedom from MRI-related complications at 1 month post-MRI was 100% in both 1.5 and 3 T arms (both p < 0.0001). The stability of pacing capture threshold was respectively at 1.5 and 3 T (atrial:: 98.9% (p = 0.001) and 100% (p < 0.0001); ventricular: both 100% (p < 0001)). The stability of sensing was respectively at 1.5 and 3 T (atrial: 100% (p = 0.0001) and 96.9% (p = 0.01); ventricular: 100% (p < 0.0001) and 99.1% (p = 0.0001)). All devices switched automatically to the programmed asynchronous mode in the MRI environment and to initially programmed mode after the MRI exam. While all MR examinations were assessed as interpretable, artifacts deteriorated a subset of examinations including mostly cardiac and shoulder ones.

CONCLUSION

This study demonstrates the safety and electrical stability of ENO®, TEO®, or OTO® pacing systems at 1 month post-MRI at 1.5 and 3 T. Even if artifacts were noticed in a subset of examinations, overall interpretability was preserved.

CLINICAL RELEVANCE STATEMENT

ENO®, TEO®, and OTO® pacing systems switch to MR-mode when detecting magnetic field and switch back on conventional mode after MRI. Their safety and electrical stability at 1 month post MRI were shown at 1.5 and 3 T. Overall interpretability was preserved.

KEY POINTS

• Patients implanted with an MRI conditional cardiac pacemaker can be safely scanned under 1.5 or 3 Tesla MRI with preserved interpretability. • Electrical parameters of the MRI conditional pacing system remain stable after a 1.5 or 3 Tesla MRI scan. • The automated MRI mode enabled the automatic switch to asynchronous mode in the MRI environment and to initial settings after the MRI scan in all patients.

Creation of pacemaker remote monitoring networks between hospital and pharmacies during Covid-19 outbreak

INTRODUCTION

Remote Monitoring (RM) of Cardiac Implantable Electronic Devices (CIEDs) is proven to be safe and efficient. It has been adopted in our center since years. At the time of the recent Covid-19 outbreak, we introduced and tested a collaborative organizational model, through a new RM device (Totem), creating a network with the surrounding territory and limiting CIED patients' presence in hospital.

METHODS

We involved 4 neighbor pharmacies where Totem devices were installed; we called and informed 64 patients with Totem compatible pacemaker (PM) about the possibility to perform their PM follow-up (FU) in-pharmacy; 58 gave their consent and their data were inserted into our RM database.

RESULTS

During an 18-month FU period, a total of 70 RM transmissions have been received: one alert of high atrial burden triggering a pharmacological optimization, one alert of high ventricular impedance leading to a new ventricular lead implantation and four alerts of elective replacement indicator. Fulfilled questionnaires revealed complete patient satisfaction.

CONCLUSIONS

A collaborative network between our hospital and the surrounding territory to perform RM FUs of CIEDs during Covid-19 pandemic was feasible, leading to patient compliance and satisfaction and revealing important technical and clinical alerts.

Five waves of COVID-19 pandemic in Italy: results of a national survey evaluating the impact on activities related to arrhythmias, pacing, and electrophysiology promoted by AIAC (Italian Association of Arrhythmology and Cardiac Pacing)

BACKGROUND

The subsequent waves of the COVID-19 pandemic in Italy had a major impact on cardiac care.

METHODS

A survey to evaluate the dynamic changes in arrhythmia care during the first five waves of COVID-19 in Italy (first: March-May 2020; second: October 2020-January 2021; third: February-May 2021; fourth: June-October 2021; fifth: November 2021-February 2022) was launched.

RESULTS

A total of 127 physicians from arrhythmia centers (34% of Italian centers) took part in the survey. As compared to 2019, a reduction in 40% of elective pacemaker (PM), defibrillators (ICD), and cardiac resynchronization devices (CRT) implantations, with a 70% reduction for ablations, was reported during the first wave, with a progressive and gradual return to pre-pandemic volumes, generally during the third-fourth waves, slower for ablations. For emergency procedures (PM, ICD, CRT, and ablations), recovery from the initial 10% decline occurred in most cases during the second wave, with some variability. However, acute care for atrial fibrillation, electrical cardioversions, and evaluations for syncope showed a prolonged reduction of activity. The number of patients with devices which started remote monitoring increased by 40% during the first wave, but then the adoption of remote monitoring declined.

CONCLUSIONS

The dramatic and profound derangement in arrhythmia management that characterized the first wave of the COVID-19 pandemic was followed by a progressive return to the volume of activities of the pre-pandemic periods, even if with different temporal dynamics and some heterogeneity. Remote monitoring was largely implemented during the first wave, but full implementation is needed.

Impact of COVID-19 Pandemic on Remote Monitoring of Cardiac Implantable Electronic Devices in Italy: Results of a Survey Promoted by AIAC (Italian Association of Arrhythmology and Cardiac Pacing)

The COVID-19 pandemic has had a profound impact on the organisation of health care in Italy, with an acceleration in the development of telemedicine. To assess the impact of the COVID-19 pandemic on the spread of remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) in Italy, a survey addressed to cardiologists operating in all Italian CIED-implanting centres was launched. A total of 127 cardiologists from 116 Italian arrhythmia centres took part in the survey, 41.0% of all 283 CIED-implanting centres operating in Italy in 2019. All participating centres declared to use RM of CIEDs. COVID-19 pandemic resulted in an increase in the use of RM in 83 (71.6%) participating centres. In a temporal perspective, an increase in the median number of patients per centre followed up by RM was found from 2012 to 2017, followed by an exponential increase from 2017 to 2020. In 36 participating centres (31.0%) a telehealth visits service was activated as a replacement for in-person outpatient visits (in patients with or without CIED) during the COVID-19 pandemic. COVID-19 pandemic has caused an acceleration in the use of RM of CIEDs and in the use of telemedicine in the clinical practice of cardiology.

Combining Home Monitoring temporal trends from implanted defibrillators and baseline patient risk profile to predict heart failure hospitalizations: results from the SELENE HF study

AIMS

We developed and validated an algorithm for prediction of heart failure (HF) hospitalizations using remote monitoring (RM) data transmitted by implanted defibrillators.

METHODS AND RESULTS

The SELENE HF study enrolled 918 patients (median age 69 years, 81% men, median ejection fraction 30%) with cardiac resynchronization therapy (44%), dual-chamber (38%), or single-chamber defibrillators with atrial diagnostics (18%). To develop a predictive algorithm, temporal trends of diurnal and nocturnal heart rates, ventricular extrasystoles, atrial tachyarrhythmia burden, heart rate variability, physical activity, and thoracic impedance obtained by daily automatic RM were combined with a baseline risk-stratifier (Seattle HF Model) into one index. The primary endpoint was the first post-implant adjudicated HF hospitalization. After a median follow-up of 22.5 months since enrolment, patients were randomly allocated to the algorithm derivation group (n = 457; 31 endpoints) or algorithm validation group (n = 461; 29 endpoints). In the derivation group, the index showed a C-statistics of 0.89 [95% confidence interval (CI): 0.83-0.95] with 2.73 odds ratio (CI 1.98-3.78) for first HF hospitalization per unitary increase of index value (P < 0.001). In the validation group, sensitivity of predicting primary endpoint was 65.5% (CI 45.7-82.1%), median alerting time 42 days (interquartile range 21-89), and false (or unexplained) alert rate 0.69 (CI 0.64-0.74) [or 0.63 (CI 0.58-0.68)] per patient-year. Without the baseline risk-stratifier, the sensitivity remained 65.5% and the false/unexplained alert rates increased by ≈10% to 0.76/0.71 per patient-year.

CONCLUSION

With the developed algorithm, two-thirds of first post-implant HF hospitalizations could be predicted timely with only 0.7 false alerts per patient-year.

Change in the use of remote monitoring of cardiac implantable electronic devices in Italian clinical practice over a 5-year period: results of two surveys promoted by the AIAC (Italian Association of Arrhythmology and Cardiac Pacing)

AIMS

The aim of this study was to evaluate the use of remote monitoring in Italian clinical practice and its trend over the last 5 years.

METHODS

In 2012 and 2017, two surveys were conducted. Both were open to all Italian implanting centres and consisted of 25 questions on the characteristics of the centre, their actual use of remote monitoring, applied organizational models and administrative and legal aspects.

RESULTS

The questionnaires were completed by 132 and 108 centres in 2012 and 2017, respectively (30.6 and 24.7% of all Italian implanting centres). In 2017, significantly fewer centres followed up fewer than 200 patients by remote monitoring than in 2012, while more followed up more than 500 patients (all P < 0.005). In most of the centres (77.6%) that responded to both surveys, the number of patients remotely monitored significantly increased from 2012 to 2017.In both surveys, remote monitoring was usually managed by physicians and nurses. Over the period, primary review of transmissions by physicians declined, while it was increasingly performed by nurses; the involvement of technicians rose, while that of manufacturers' technical personnel decreased. The percentage of centres in which transmissions were submitted to the physician only in critical cases rose (from 28.3 to 64.3%; P < 0.001). In 86.7% of centres, the lack of a reimbursement system was deemed the main barrier to implementing remote monitoring.

CONCLUSION

In the last 5 years, the number of patients followed up by remote monitoring has increased markedly. In most Italian centres, remote monitoring has increasingly been managed through a primary nursing model. The lack of a specific reimbursement system is perceived as the main barrier to implementing remote monitoring .

P2592Combining home monitoring temporal trends and baseline patient risk profile for predicting impending heart failure hospitalizations. Results from the SELENE HF (BIO.Detect HF IV) study

Background/Introduction

The lack of a validated method to efficiently combine information provided by Remote Monitoring (RM) of implantable defibrillators (ICD) and patient clinical profile has limited the use of RM in the prevention of worsening heart failure episodes.

Purpose

Our objective was to develop and validate an index combining RM temporal trends and a baseline risk score for predicting the first HF hospitalization after device implantation.

Methods

We prospectively enrolled 918 patients (81% male, median age 69, interquartile interval [QI], 61/76; Seattle Heart Failure Score [SHFS], 0.17, QI, −0.40/0.75) with indication to ICD (56%), or ICD with cardiac resynchronization therapy (44%). The Home Monitoring (HM) system was activated in all patients after implant to collect several technical and HF-related variables daily. Investigators were blinded to HM reports, and only received automatic alerts for critical technical issues. The primary endpoint was the first adjudicated HF hospitalization. The cohort was a posteriori 1:1 randomized in derivation and validation groups stratified by device type and primary endpoint occurrence. The SHFS was used for baseline risk assessment.

Results

During a median follow-up of 23 months (QI, 14/36), 62 first HF hospitalizations were adjudicated. In the derivation group, the index was constructed by combining the SHFS and temporal trends of 24-hour and rest mean heart rates, ventricular ectopic beat frequency, arrhythmic atrial burden, heart rate variability, physical exercise, and thoracic impedance. Variable selection was based on an automatic stepwise procedure, after applying appropriate transformations in variable-specific time frames to maximize the area under the receiver operating characteristics curve (AUC). The resulting index was associated to an AUC of 0.88 and an Odds Ratio of 2.72 (confidence interval [CI] 1.97–3.75, p<0.001) for index unitary increase. In the index validation test, first HF hospitalizations were predicted with a sensitivity of 73.3% (CI, 54.1%-87.7%), a median alerting time of 55 days (QI, 20/68), false alert rate of 0.75 (CI, 0.70–0.81) patient-year, and 95.1% false-alert-free days.

Conclusion

HM temporal trends of selected variables and the SHFS may be combined to timely and efficiently predict the first HF hospitalization after implant, with less than 1 expected per-patient false alert per year.

Acknowledgement/Funding

BIOTRONIK SE & Co. KG, Berlin, Germany

Atrioventricular Interval Extension Is Highly Efficient in Preventing Unnecessary Right Ventricular Pacing in Sinus Node Disease: A Randomized Cross-Over Study Versus Dual- to Atrial Single-Chamber Mode Switch

OBJECTIVES

This study sought to compare the Intrinsic Rhythm Support (IRSplus) and Ventricular Pace Suppress (VpS) in terms of right ventricular pacing percentage (VP %), mean atrioventricular interval (MAVI), atrial fibrillation, and cardiac volumes.

BACKGROUND

Modern pacemakers are provided with algorithms for reducing unnecessary ventricular pacing. These may be classified as: periodic search for intrinsic atrioventricular (AV) conduction prolonging the AV delay accordingly; or DDD-ADI mode switch. The IRSplus and VpS algorithms belong to the former and latter classes, respectively.

METHODS

Patients with sick sinus dysfunction without evidence of II/III degree AV block were 1:1 randomized to 6-month periods of either IRSplus or VpS, and then crossed over. Subsequent follow-ups were at the 12th month after randomization for device data retrieving, and at the 18th month with the same device programming for echocardiographic assessment.

RESULTS

A total of 230 patients (62% males, median age 75 years [interquartile range: 69 to 79 years]) were enrolled. At a linear mixed-model analysis with order of treatment and investigational sites as nested random effects, differences in VP% and MAVI reached statistical significance: VP% was 1% (0% to 11%) during IRSplus and 3% (0% to 26%) during VpS (p = 0.029); MAVI was 225 ms (198 to 253 ms) during IRSplus and 214 ms (188 to 240 ms) during VpS (p = 0.014). No differences were observed in atrial fibrillation burden and incidence, ejection fraction, and cardiac volumes.

CONCLUSIONS

Both IRSplus and VpS algorithms ensured VP% ≤3% in most patients with sinus node dysfunction and preserved AV conduction. The IRSplus was slightly more efficient in reducing VP% at the expense of a small MAVI increase, with statistical but clinically insignificant differences. (Ventricular Pace Suppression Versus Intrinsic Rhythm Support Study; NCT01528657).

[Remote monitoring of implantable cardiac devices: health technology assessment ]

Clinical follow-up of patients with cardiac implantable electronic devices is challenging because of the increasing technical complexity of devices and clinical complexity of patients. Remote monitoring (RM) offers the opportunity to optimize clinic workflow and to improve device monitoring and patient management by reducing in-hospital visits, physician and nurse time required for patient follow-up, and hospital and social costs. Continuous RM may lead to early detection of device malfunctions and clinical events, such as arrhythmias and heart failure. Early reaction may improve patient outcome. RM is easy to use and patients show a high level of acceptance and satisfaction. Implementing RM in daily practice may require changes in clinical workflow. Primary nursing-based models have demonstrated the best results. In spite of a favorable cost-benefit ratio, RM reimbursement still represents an issue in several European countries, including Italy, which limits widespread RM utilization. The fee-for-service payment approach, the global budget for device patient follow-up and/or integrated care packages for heart failure management represent the keys to introduce reimbursement and to improve patient care, while reducing healthcare costs.

Cardiac pacing in patients with neurally mediated syncope and documented asystole: effectiveness analysis from the Third International Study on Syncope of Uncertain Etiology (ISSUE-3) Registry

AIMS

The randomized, double-blind Third International Study on Syncope of Uncertain Etiology (ISSUE-3) showed that dual-chamber permanent pacing was effective in reducing the recurrence of syncope in patients ≥ 40 years with severe asystolic, probably neurally mediated syncope (NMS), documented by implantable loop recorder (ILR). Analysis in ISSUE-3 was performed according to the intention-to-treat principle. In the present study, we performed an on-treatment analysis, which included additionally those non-randomized patients followed up in the ISSUE registry to evaluate in a better manner the effectiveness of cardiac pacing therapy.

METHODS AND RESULTS

Initially, 504 patients received an ILR, 162 (32%) patients had a diagnosis consistent with NMS within a mean observation period of 15 ± 11 months: 99 (19%) patients had documentation of syncope with ≥ 3 s asystole or ≥ 6 s asystole without syncope. Sixty patients affected by asystolic NMS received cardiac pacing therapy and 86 (33 asystolic and 53 non-asystolic NMS) were untreated; 16 patients were lost to follow-up. Paced and unpaced groups had similar clinical characteristics. During subsequent follow-up, syncope recurred in 10 paced (17%) and in 40 non-paced (46%) patients. At 21 months, the estimated product-limit syncope recurrence rates were 27% [95% confidence interval (CI) 15-47] and 54% (95% CI 43-67), respectively (P = 0.01). With cardiac pacing, the risk of recurrence was reduced by 57% (hazard ratio = 0.43, 95% CI = 0.2-0.8). Complications of pacemaker therapy were haemothorax at implantation in one patient and lead dislodgement that required correction in two patients.

CONCLUSION

Permanent cardiac pacing is effective in reducing recurrence of syncope in patients ≥ 40 years with severe asystolic possible NMS with a few complications. The study shows that 61% of patients with a diagnosis of NMS made by ILR received a pacemaker but 5.1 ILRs had to be implanted to find one patient who finally had a pacemaker implanted.

Baseline heart rate variability predicts clinical events in heart failure patients implanted with cardiac resynchronization therapy: validation by means of related complexity index

BACKGROUND

Studies on the physiology of the cardiovascular system suggest that generation of the heart rate (HR) signal is governed by nonlinear dynamics. Linear and nonlinear indices of HR variability (HRV) have been shown to predict outcome in heart failure (HF). Aim of the present study is to assess if a HR-related complexity predicts adverse clinical and cardiovascular events at 1 year in patients implanted with cardiac resynchronization therapy (CRT).

METHODS

In sixty patients implanted with CRT (Renewal), 24-hour HR data were retrieved at patient discharge and 1-year follow-up. A set of linear indices of HRV were considered: mean HR, standard deviation of normal beat to normal beat (SDANN), and HR footprint. Two novel nonlinear indices were calculated by means of a specific algorithm (OntoSpace): HR-complexity (HR-Co) and HR-entropy (HR-En). Predictors of adverse clinical outcome (functional class deterioration or major hospitalizations for cardiovascular causes or all-cause mortality) and of HRV recovery were sought by means of multivariate analysis.

RESULTS

HR-Co and HR-En were found to be highly correlated with the other traditional indices of HRV. Lower baseline values of COMPLEXITY WERE ASSOCIATED WITH ADVERSE CLINICAL OUTCOMES (HAZARD RATIO [HR] 0.71; 95% CONFIDENCE INTERVAL [CI] 0.54-0.95; P < 0.02).

CONCLUSION

Complexity and entropy indices, calculated from 24-hour normal beat to normal beat (RR) intervals well represent patient's autonomic function. In this limited set of data, HF patients with lower baseline complexity-related indices, representing a more compromised autonomic function, present worse clinical outcome at 1-year follow-up.

Atrial tachyarrhythmia burden modelling by some electrophysiological parameters in pacemaker-recipient patients with Brady–Tachy syndrome

AIMS

(1) To correlate atrial tachyarrhythmia (AT) burden of pacemaker-recipient Brady-Tachy syndrome (BTS) patients with a number of diagnostics-derived parameters after 1 month of DDD pacing; (2) to asses whether the activation of atrial overdrive or conventional rate-responsive pacing may affect relevant variables and their correlation.

METHODS AND RESULTS

After 1 month of DDD pacing, rate-responsive function or persistent atrial overdrive was randomly activated for 3 months, in 92 BTS patients. Some pacemaker diagnostics parameters collected at 1- and 4-month follow-ups were included in multiple linear regression models, whose dependent variable was the Log transformation of AT burden and compared. With 1-month data, the only variables significantly correlating with Log AT burden were average (with a regression coefficient estimate of -0.07, P=0.02) and standard deviation (0.10, P=0.007) of atrial rate, mean premature atrial contraction (PAC) coupling interval (CI) (-0.005, P=0.001), frequency of PACs with CI<500 ms (1.30, P<10(-6)). Atrial pacing percentage (APP) and ventricular pacing percentage (VPP), PACs with CI>500 ms did not significantly correlate. Four-month data largely confirmed these results, except that in DDDR atrial rate average and standard deviation no longer correlated. Overdrive significantly increased APP and reduced PACs with CI>500 ms.

CONCLUSION

AT burden showed significant dependence in DDD and during overdrive on atrial rate average and standard deviation. Highly premature PACs always significantly correlated with AT burden. Though increasing APP, which unexpectedly never correlated, overdrive could only reduce less premature PACs.