Regional Variations in Medical Device Diffusion

Despite established efficacy for cardiac implantable electrical devices (CIEDs), large differences in CIED implant rates have been documented across and within countries. The aim of this paper is to investigate the influence of socio‐economic, epidemiological and supply side factors on CIED implant rates across 57 Regions in 5 EU countries and to assess the feasibility of using administrative data for this purpose. A total of 1 330 098 hospitalizations for CIED procedures extracted from hospital discharge databases in Austria, England, Germany, Italy and Slovenia from 2008 to 2012 was used in the analysis. Higher levels of tertiary education among the labour force and percent of aged population are positively associated with implant rates of CIED. Regional per capita GDP and number of implanting centres appear to have no significant effect. Institutional factors are shown to be important for the diffusion of CIED. Wide variation in CIED implant rates across and within five EU countries is undeniable. However, regional factors play a limited part in explaining these differences with few exceptions. Administrative databases are a valuable source of data for investigating the diffusion of medical technologies, while the choice of appropriate modelling strategy is crucial in identifying the drivers for variation across countries. © 2017 The Authors. Health Economics published by John Wiley & Sons, Ltd

Five year trends (2008-2012) in cardiac implantable electrical device utilization in 5 European nations: a case study in cross-country comparisons using administrative databases

Aims Common methodologies for analysis of analogous data sets are needed for international comparisons of treatment and outcomes. This study tests using administrative hospital discharge (HD) databases in five European countries to investigate variation/trends in pacemaker (PM) and implantable cardioverter defibrillator (ICD) implant rates in terms of patient characteristics/management, device subtype, and initial implantation vs. replacement, and compares findings with existing literature and European Heart Rhythm Association (EHRA) reports. Methods and results HD databases from 2008 to 2012 in Austria, England, Germany, Italy and Slovenia were interrogated to extract admissions (without patient identification) associated with PM and ICD implants and replacements, using direct cross-referencing of procedure codes and common methodology to compare aggregate data. 1 338 199 records revealed 212 952 PM and 62 567 ICD procedures/year on average for a 204.4 million combined population, a crude implant rate of about 104/100 000 inhabitants for PMs and 30.6 for ICDs. The first implant/replacement rate ratios were 81/24 (PMs) and 25/7 (ICDs). Rates have increased, with cardiac resynchronization therapy (CRT) subtypes for both devices rising dramatically. Significant between- and within-country variation persists in lengths of stay and rates (Germany highest, Slovenia lowest). Adjusting for age lessened differences for PM rates, scarcely affected ICDs. Male/female ratios remained stable at 56/44% (PMs) and 79/21% (ICDs). About 90% of patients were discharged to home; 85-100% were inpatient admissions. Conclusion To aid in policymaking and track outcomes, HD administrative data provides a reliable, relatively cheap, methodology for tracking implant rates for PMs and ICDs across countries, as comparisons to EHRA data and the literature indicated

QRS pattern and improvement in right and left ventricular function after cardiac resynchronization therapy: a radionuclide study

Predicting response to cardiac resynchronization therapy (CRT) remains a challenge. We evaluated the role of baseline QRS pattern to predict response in terms of improvement in biventricular ejection fraction (EF)

Telecardiology and Remote Monitoring of Implanted Electrical Devices: The Potential for Fresh Clinical Care Perspectives

Telecardiology may help confront the growing burden of monitoring the reliability of implantable defibrillators/pacemakers. Herein, we suggest that the evolving capabilities of implanted devices to monitor patients’ status (heart rhythm, fluid overload, right ventricular pressure, oximetry, etc.) may imply a shift from strictly device-centered follow-up to perspectives centered on the patient (and patient-device interactions). Such approaches could provide improvements in health care delivery and clinical outcomes, especially in the field of heart failure. Major professional, policy, and ethical issues will have to be overcome to enable real-world implementation. This challenge may be relevant for the evolution of our health care systems

Electromechanical effects and optimization modalities of cardiac resynchronization therapy

Background and aims Heart failure is a major health care problem, with high morbidity and mortality rates. In recent years, cardiac resynchronization therapy (CRT) has become an established additive treatment for patients with advanced heart failure, left ventricular (LV) dysfunction, and wide QRS complex. CRT is a stimulation technique based on right ventricular (RV) and LV pacing, usually in synchrony, delivered by a pacemaker or a cardioverter-defibrillator. Significant improvements in heart failure symptoms, hospitalization rates and mortality have been documented after initiation of CRT treatment. However, to date, 20% to 30% of patients do not respond to CRT (non responders), and improved management strategies are important. This thesis explores the acute and long-term electromechanical effects of CRT at rest and during stress, and investigates novel methods for CRT optimization. Study I Twenty-one heart failure patients, responders to CRT, were assessed by low-dose dobutamine stress echocardiography, clinical evaluation and analysis of brain natriuretic peptide at two times: during active CRT ( on ) and after withholding of CRT for two weeks ( off ). Clinical, neurohormonal and echocardiographic results were compared between on and off conditions. This short-term cessation of CRT was associated with a deterioration of LV performance and a slight clinical impairment. Conclusion: The beneficial effects of CRT on LV systolic and diastolic function, observed at rest, were sustained during dobutamine stress, and this was mainly owing to maintained improvement in inter- and intraventricular synchrony. Study II Twenty-two heart failure patients with idiopathic dilated cardiomyopathy (without any evidence of significant coronary artery disease at previous angiography), who had successfully responded to CRT, underwent echocardiographic assessment of left anterior descending coronary artery (LAD) flow and intraventricular dyssynchrony during different pacing modes. Changes in LAD flow variables were correlated with simultaneous variations in intraventricular dyssynchrony. The mean coronary flow velocity increased by comparison with intrinsic conduction during simultaneous biventricular pacing (p = 0.0063) and biventricular pacing with LV preactivation (p < 0.0001), and was higher in the latter programming mode (p = 0.027). Conclusion: In patients with idiopathic dilated cardiomyopathy, simultaneous biventricular pacing and biventricular pacing with LV preactivation increase LAD flow, and this is associated with a reduction in intraventricular dyssynchrony. Study III Long-term variations in atrioventricular (AV) and interventricular (VV) delays were prospectively investigated in 37 heart failure patients subjected to echo-guided CRT optimization. All patients underwent CRT optimization within 48 hours of implantation and again after 6 months. Additionally, optimization at 12 months was performed in the first 14 patients enrolled. Conclusion: Echocardiographic optimization of AV and VV delays is associated with broad intraindividual variability. A new assessment of optimized VV delays during long-term follow-up reveals nonconcordance with previous values and provides a further increase in forward stroke volume. Study IV Twenty-four CRT patients were assessed both by echocardiography and by an automated intracardiac electrogram (IEGM) method with regard to optimal AV and VV delays. In addition, the acute impact of exercise CRT optimization on hemodynamic variables was investigated. Significant rest-to-exercise changes in optimal VV delay, but not in AV delay, were observed. Reassessment of optimal device programming during ongoing exercise resulted in an improvement in LV dyssynchrony and hemodynamic parameters, giving an additional benefit to that provided by optimization performed at rest. Conclusion: The IEGM method seems to be a promising alternative to the standard echocardiographic approach, both at rest and during exercise. Study V Twelve heart failure patients were evaluated for acute changes in multiple vector intracardiac impedance (ICZ) signals during implantation of a CRT device operating in different pacing modes. Bipolar (Z1) and quadripolar (Z2) impedance signals, recorded in the RV and between the LV and RV, respectively, were analyzed with respect to amplitude and systolic slope, and correlated with noninvasive hemodynamic and echocardiographic variables. The Z1 and Z2 variables correlated positively with all noninvasive hemodynamic variables and LV and RV ejection fractions, and inversely with LV and RV volumes. The Z2 systolic slope correlated with the interventricular conduction delay (r = 0.33, p < 0.05). Conclusion: Multiple vector ICZ measurement may be a feasible tool for hemodynamic assessment in patients treated with biventricular pacing. Summary In heart failure patients, CRT has been shown to improve symptoms, exercise capacity and survival. Our findings suggest that in long-term responders, the benefits of CRT on LV synchrony and function that are observed at rest are sustained during pharmacological stress, thereby providing a link between pathophysiological mechanisms and clinical evidence of improved exercise capacity. The finding of increased LAD flow during biventricular pacing highlights a possible additional mechanism responsible for the beneficial effects of CRT. CRT optimization has been shown to provide acute hemodynamic benefits. The dynamic changes in optimal AV and VV delays during long-term follow-up and from rest to exercise suggest that reevaluations of CRT programming may be useful. Novel automated device-based algorithms seem to be a feasible alternative to echocardiography for CRT optimization. Furthermore, multiple vector ICZ measurement may be a promising tool for hemodynamic assessment and optimization in CRT patients

Cardiovascular Imaging Applications in Clinical Management of Patients Treated with Cardiac Resynchronization Therapy

Cardiovascular imaging techniques, including echocardiography, nuclear cardiology, multi-slice computed tomography, and cardiac magnetic resonance, have wide applications in cardiac resynchronization therapy (CRT). Our aim was to provide an update of cardiovascular imaging applications before, during, and after implantation of a CRT device. Before CRT implantation, cardiovascular imaging techniques may integrate current clinical and electrocardiographic selection criteria in the identification of patients who may most likely benefit from CRT. Assessment of myocardial viability by ultrasound, nuclear cardiology, or cardiac magnetic resonance may guide optimal left ventricular (LV) lead positioning and help to predict LV function improvement by CRT. During implantation, echocardiographic techniques may guide in the identification of the best site of LV pacing. After CRT implantation, cardiovascular imaging plays an important role in the assessment of CRT response, which can be defined according to LV reverse remodeling, function and dyssynchrony indices. Furthermore, imaging techniques may be used for CRT programming optimization during follow-up, especially in patients who turn out to be non-responders. However, in the clinical settings, the use of proposed functional indices for different imaging techniques is still debated, due to their suboptimal feasibility and reproducibility. Moreover, identifying CRT responders before implantation and turning non-responders into responders at follow-up remain challenging issues

Implant rates of cardiac implantable electrical devices in Europe: A systematic literature review

Background: In recent years, indications for cardiac implantable electrical devices (CIEDs) have broadened; however, budget constraints can significantly impact patient access to these life-saving health technologies. Objective: To perform a systematic literature review on the implant rates of pacemakers, cardioverter-defibrillators, and cardiac resynchronization therapy devices in Europe over the last decade to provide insight into the possible reasons for differences across regions or countries. Methods: Four electronic databases were searched to find studies describing CIED implant rates in Europe. Fifty-eight studies were included. Results: An overview showed a recent rise in CIED implants, with large geographic differences. The ratio between the regions with the highest and lowest implant rates within the same country ranged between 1.3 and 3.4 for pacemakers and between 1.7 and 44.0 for defibrillators. The ratio between the countries with the highest and lowest implant rates ranged between 2.3 and 87.5 for pacemakers, between 3.1 and 1548.0 for defibrillators, and between 4.1 and 221.0 for resynchronization therapy devices. Implant rate variability appears to be influenced by health care, economic, demographic, and cultural factors. Conclusion: Publications on CIED implant rates in Europe show a wide variability within and across countries, the determinants of which are only partially investigated. Policy making should improve regarding equity of access to better care