Implantation of cardiac electronic devices in active COVID-19 patients: Results from an international survey

BACKGROUND

Cardiac implantable electronic device (CIED) implantation rates as well as the clinical and procedural characteristics and outcomes in patients with known active coronavirus disease 2019 (COVID-19) are unknown.

OBJECTIVE

The purpose of this study was to gather information regarding CIED procedures during active COVID-19, performed with personal protective equipment, based on an international survey.

METHODS

Fifty-three centers from 13 countries across 4 continents provided information on 166 patients with known active COVID-19 who underwent a CIED procedure.

RESULTS

The CIED procedure rate in 133,655 hospitalized COVID-19 patients ranged from 0 to 16.2 per 1000 patients (P <.001). Most devices were implanted due to high-degree/complete atrioventricular block (112 [67.5%]) or sick sinus syndrome (31 [18.7%]). Of the 166 patients in the study survey, the 30-day complication rate was 13.9% and the 180-day mortality rate was 9.6%. One patient had a fatal outcome as a direct result of the procedure. Differences in patient and procedural characteristics and outcomes were found between Europe and North America. An older population (76.6 vs 66 years; P <.001) with a nonsignificant higher complication rate (16.5% vs 7.7%; P = .2) was observed in Europe vs North America, whereas higher rates of critically ill patients (33.3% vs 3.3%; P <.001) and mortality (26.9% vs 5%; P = .002) were observed in North America vs Europe.

CONCLUSION

CIED procedure rates during known active COVID-19 disease varied greatly, from 0 to 16.2 per 1000 hospitalized COVID-19 patients worldwide. Patients with active COVID-19 infection who underwent CIED implantation had high complication and mortality rates. Operators should take these risks into consideration before proceeding with CIED implantation in active COVID-19 patients.

Performance evaluation of implantable cardioverter-defibrillators with SmartShock technology in patients with inherited arrhythmogenic diseases

BACKGROUND

Patients with inherited arrhythmogenic diseases (IADs) are often prescribed preventative implantable cardioverter-defibrillators (ICDs) to manage their increased sudden cardiac arrest risk. However, it has been suggested that ICDs in IAD patients may come with additional risk. We aimed to leverage the PainFree SmartShock Technology dataset to compare inappropriate therapies, appropriate therapies, mortality, and complications in patients with and without IAD.

METHODS

This retrospective analysis included extracted, physician-adjudicated, arrhythmic episodes from ICD devices. The incidence of arrhythmic events was estimated with the Kaplan-Meier method using the log-rank test. Cox proportional hazards regression was used to estimate hazard ratios (HRs) with their 95% confidence intervals (CIs).

RESULTS

Of the 1699 ICD patients, 77 patients (4.5%) had IAD. Incidence of inappropriate shock was similar in both patients with (3.2% at 24 months) and without (3.8% at 24 months) IAD (HR: 0.80, CI: 0.19-3.30, p = 0.76). In a multivariable analysis IAD was not significantly associated with reduced mortality (HR: 0.64, CI: 0.08-4.80, p = 0.66). The rates of complications were numerically lower in patients with IAD vs without (8.8% vs 9.6% at 24 months respectively), but not statistically significant (HR: 0.83, CI: 0.20-3.38, p = 0.79).

CONCLUSIONS

IAD patients showed a very low annual rate of inappropriate therapy. This suggests that newer algorithms, such as the SST algorithm, are equally good at identifying and treating life-threatening arrhythmias in patients regardless of whether they have IAD.

OUP accepted manuscript

Aims

We aimed to investigate the association of clinically overt and silent brain lesions with cognitive function in atrial fibrillation (AF) patients.

Methods and results

We enrolled 1227 AF patients in a prospective, multicentre cohort study (Swiss-AF). Patients underwent standardized brain magnetic resonance imaging (MRI) at baseline and after 2 years. We quantified new small non-cortical infarcts (SNCIs) and large non-cortical or cortical infarcts (LNCCIs), white matter lesions (WML), and microbleeds (Mb). Clinically, silent infarcts were defined as new SNCI/LNCCI on follow-up MRI in patients without a clinical stroke or transient ischaemic attack (TIA) during follow-up. Cognition was assessed using validated tests. The mean age was 71 years, 26.1% were females, and 89.9% were anticoagulated. Twenty-eight patients (2.3%) experienced a stroke/TIA during 2 years of follow-up. Of the 68 (5.5%) patients with ≥1 SNCI/LNCCI, 60 (88.2%) were anticoagulated at baseline and 58 (85.3%) had a silent infarct. Patients with brain infarcts had a larger decline in cognition [median (interquartile range)] changes in Cognitive Construct score [−0.12 (−0.22; −0.07)] than patients without new brain infarcts [0.07 (−0.09; 0.25)]. New WML or Mb were not associated with cognitive decline.

Conclusion

In a contemporary cohort of AF patients, 5.5% had a new brain infarct on MRI after 2 years. The majority of these infarcts was clinically silent and occurred in anticoagulated patients. Clinically, overt and silent brain infarcts had a similar impact on cognitive decline.

Clinical Trial Registration

ClinicalTrials.gov Identifier: NCT02105844, https://clinicaltrials.gov/ct2/show/NCT02105844

Long-term outcome of catheter ablation for atrial fibrillation in patients with severe left atrial enlargement and reduced left ventricular ejection fraction

AIMS

Data regarding the efficacy of catheter ablation in heart failure patients with severely dilated left atrium and reduced left ventricular ejection fraction (LVEF) are scanty. We sought to assess the efficacy of catheter ablation in patients with reduced LVEF and severe left atrial (LA) enlargement, and to compare it to those patients with preserved left ventricular function and equally dilated left atrium.

METHODS AND RESULTS

Three patient groups with paroxysmal or persistent atrial fibrillation (AF) undergoing a first pulmonary vein isolation (PVI) were considered: Group 1 included patients with normal or mildly abnormal LA volume (≤41 mL/m2) and normal LVEF; Group 2 included patients with severe LA enlargement (>48 mL/m2) and normal LVEF; and Group 3 included patients with severe LA enlargement and reduced LVEF. Time to event analysis was used to investigate AF recurrences. The study cohort includes 439 patients; Group 3 had a higher prevalence of cardiovascular risk factors. LA enlargement was associated with a two-fold in risk of AF recurrence, on the contrary only a smaller non-significant increase of 30% was shown with the further addition of LVEF reduction.

CONCLUSIONS

The long-term outcome of patients with severe LA dilatation and reduced LVEF is comparable to those with severe LA enlargement but preserved LVEF. Long-term efficacy of PVI is certainly affected by the enlargement of the left atrium, but less so by the addition of a reduced LVEF. CA remains the best strategy for rhythm control both in paroxysmal and persistent AF in this subgroup of patients.

Lead fixation mechanism impacts outcome of transvenous lead extraction: Data from the European Lead Extraction ConTRolled Registry

AIMS

The aims of this study is to characterize the transvenous lead extraction (TLE) population with active (A) compared with passive fixation (PFix) leads and to compare the safety, efficacy, and ease of extracting active fixation (AFix) compared with PFix right atrial (RA) and right ventricular (RV) leads.

METHODS AND RESULTS

The European Lead Extraction ConTRolled Registry (ELECTRa) was analysed. Patients were divided into three groups; those with only AFix, only PFix, and combined Fix leads. Three outcomes were defined. Difficult extraction, complete radiological, and clinical success. Multivariate model was used to analyse the independent effect of Fix mechanism on these outcomes. The study included 2815 patients, 1456 (51.7%) with only AFix leads, 982 (34.9%) with only PFix leads, and 377 (13.4%) with combined Fix leads. Patients with AFix leads were younger with shorter lead dwelling time. Infection was the leading cause for TLE among the combined Fix group with lowest rates among AFix group. No difference in complications rates was noted between patients with only AFix vs. PFix leads. Overall, there were 1689 RA (1046 AFix and 643 PFix) and 2617 RV leads (1441 AFix and 1176 PFix). Multivariate model demonstrated that PFix is independently associated with more difficult extraction for both RA and RV leads, lower radiological success in the RA but has no effect on clinical success.

CONCLUSION

Mechanism of Fix impact the ease of TLE of RA and RV leads and rates of complete radiological success in the RA but not clinical success. These findings should be considered during implantation and TLE procedures.

Right ventricular outflow tract electroanatomical abnormalities in asymptomatic and high-risk symptomatic patients with Brugada syndrome: Evidence for a new risk stratification tool?

INTRODUCTION

Microstructural abnormalities at the epicardium of the right ventricular outflow tract (RVOT) may provide the arrhythmia substrate in Brugada syndrome (BrS). Endocardial unipolar electroanatomical mapping allows the identification of epicardial abnormalities. We evaluated the clinical implications of an abnormal endocardial substrate as perceived by high-density electroanatomical mapping (HDEAM) in patients with BrS.

METHODS

Fourteen high-risk BrS patients with aborted sudden cardiac death (SCD) (12 males, mean age: 41.9 ± 11.8 years) underwent combined endocardial-epicardial HDEAM of the right ventricle/RVOT, while 40 asymptomatic patients (33 males, mean age: 42 ± 10.7 years) underwent endocardial HDEAM. Based on combined endocardial-epicardial procedures, endocardial HDEAM was considered abnormal in the presence of low voltage areas (LVAs) more than 1 cm² with bipolar signals less than 1 mV and unipolar signals less than 5.3 mV. Programmed ventricular stimulation (PVS) was performed in all patients.

RESULTS

The endocardial unipolar LVAs were colocalized with epicardial bipolar LVAs (p = .0027). Patients with aborted SCD exhibited significantly wider endocardial unipolar (p < .01) and bipolar LVAs (p < .01) compared with asymptomatic individuals. A substrate size of unipolar LVAs more than 14.5 cm² (area under the curve [AUC]: 0.92, p < .001] and bipolar LVAs more than 3.68 cm² (AUC: 0.82, p = .001) distinguished symptomatic from asymptomatic patients. Patients with ventricular fibrillation inducibility (23/54) demonstrated broader endocardial unipolar (p < .001) and bipolar LVAs (p < .001) than noninducible patients. The presence of unipolar LVAs more than 13.5 cm² (AUC: 0.95, p < .001) and bipolar LVAs more than 2.97 cm² (AUC: 0.78, p < .001) predicted a positive PVS.

CONCLUSION

Extensive endocardial electroanatomical abnormalities identify high-risk patients with BrS. Endocardial HDEAM may allow risk stratification of asymptomatic patients referred for PVS.

Filamin C missense variant associated with severe right atrial disease and skeletal myopathy

INTRODUCTION

Filamin C (FLNC) gene variants associated with atrial cardiomyopathies have not been reported so far. The aim of this study was to assess the genetics of two siblings presenting with recurrent right atrial arrhythmias, severe right atrial dilatation, and skeletal myopathy.

METHODS

A family with subjects affected by recurrent atrial arrhythmias and skeletal myopathy was extensively evaluated by the means of electrocardiographic recordings, magnetic resonance, intracardiac high-density mapping, and genetic testing.

RESULTS

Two siblings with right atrial arrhythmias and severe right atrial disease were found to be heterozygous carriers of the variant FLNC-c.925G>A p.(Glu309Lys), previously reported as a variant of uncertain significance. Despite the presence of a severe dilatation of the right atrium in both patients, one presented with skeletal muscle myopathy and an atrial arrhythmia refractory to pharmacological and invasive treatment, while the other one did not have any myopathy, and rhythm control was easily achieved by drugs.

CONCLUSION

Filamin C missense variant c.925G>A p.(Glu309Lys) is associated with the severe right atrial disease. Considering cosegregation with the disease (PP1 supporting), this variant should be classified as likely pathogenic.

Synergistic antiarrhythmic effect of inward rectifier current inhibition and pulmonary vein isolation in a 3D computer model for atrial fibrillation

AIMS

Recent clinical studies showed that antiarrhythmic drug (AAD) treatment and pulmonary vein isolation (PVI) synergistically reduce atrial fibrillation (AF) recurrences after initially successful ablation. Among newly developed atrial-selective AADs, inhibitors of the G-protein-gated acetylcholine-activated inward rectifier current (IKACh) were shown to effectively suppress AF in an experimental model but have not yet been evaluated clinically. We tested in silico whether inhibition of inward rectifier current or its combination with PVI reduces AF inducibility.

METHODS AND RESULTS

We simulated the effect of inward rectifier current blockade (IK blockade), PVI, and their combination on AF inducibility in a detailed three-dimensional model of the human atria with different degrees of fibrosis. IK blockade was simulated with a 30% reduction of its conductivity. Atrial fibrillation was initiated using incremental pacing applied at 20 different locations, in both atria. IK blockade effectively prevented AF induction in simulations without fibrosis as did PVI in simulations without fibrosis and with moderate fibrosis. Both interventions lost their efficacy in severe fibrosis. The combination of IK blockade and PVI prevented AF in simulations without fibrosis, with moderate fibrosis, and even with severe fibrosis. The combined therapy strongly decreased the number of fibrillation waves, due to a synergistic reduction of wavefront generation rate while the wavefront lifespan remained unchanged.

CONCLUSION

Newly developed blockers of atrial-specific inward rectifier currents, such as IKAch, might prevent AF occurrences and when combined with PVI effectively supress AF recurrences in human.

EHRA expert consensus statement and practical guide on optimal implantation technique for conventional pacemakers and implantable cardioverter-defibrillators: endorsed by the Heart Rhythm Society (HRS), the Asia Pacific Heart Rhythm Society (APHRS), and the Latin-American Heart Rhythm Society (LAHRS)

With the global increase in device implantations, there is a growing need to train physicians to implant pacemakers and implantable cardioverter-defibrillators. Although there are international recommendations for device indications and programming, there is no consensus to date regarding implantation technique. This document is founded on a systematic literature search and review, and on consensus from an international task force. It aims to fill the gap by setting standards for device implantation.

Reconstruction of three-dimensional biventricular activation based on the 12-lead electrocardiogram via patient-specific modelling

Aims

Non-invasive imaging of electrical activation requires high-density body surface potential mapping. The nine electrodes of the 12-lead electrocardiogram (ECG) are insufficient for a reliable reconstruction with standard inverse methods. Patient-specific modelling may offer an alternative route to physiologically constraint the reconstruction. The aim of the study was to assess the feasibility of reconstructing the fully 3D electrical activation map of the ventricles from the 12-lead ECG and cardiovascular magnetic resonance (CMR).

Methods and results

Ventricular activation was estimated by iteratively optimizing the parameters (conduction velocity and sites of earliest activation) of a patient-specific model to fit the simulated to the recorded ECG. Chest and cardiac anatomy of 11 patients (QRS duration 126–180 ms, documented scar in two) were segmented from CMR images. Scar presence was assessed by magnetic resonance (MR) contrast enhancement. Activation sequences were modelled with a physiologically based propagation model and ECGs with lead field theory. Validation was performed by comparing reconstructed activation maps with those acquired by invasive electroanatomical mapping of coronary sinus/veins (CS) and right ventricular (RV) and left ventricular (LV) endocardium. The QRS complex was correctly reproduced by the model (Pearson’s correlation r = 0.923). Reconstructions accurately located the earliest and latest activated LV regions (median barycentre distance 8.2 mm, IQR 8.8 mm). Correlation of simulated with recorded activation time was very good at LV endocardium (r = 0.83) and good at CS (r = 0.68) and RV endocardium (r = 0.58).

Conclusion

Non-invasive assessment of biventricular 3D activation using the 12-lead ECG and MR imaging is feasible. Potential applications include patient-specific modelling and pre-/per-procedural evaluation of ventricular activation.

Impact of contact force sensing technology on outcome of catheter ablation of idiopathic pre-mature ventricular contractions originating from the outflow tracts

AIMS

Catheter ablation of frequent idiopathic pre-mature ventricular contractions (PVC) is increasingly performed. While potential benefits of contact force (CF)-sensing technology for atrial fibrillation ablation have been assessed in several studies, the impact of CF-sensing on ventricular arrhythmia ablation remains unknown. This study aimed to compare outcomes of idiopathic outflow tract PVC ablation when using standard ablation catheters as opposed to CF-sensing catheters.

METHODS AND RESULTS

In a retrospective multi-centre study, unselected patients undergoing catheter ablation of idiopathic outflow tract PVCs between 2013 and 2016 were enrolled. All procedures were performed using irrigated-tip ablation catheters and a 3D electro-anatomical mapping system. Sustained ablation success was defined as a  ≥80% reduction of pre-procedural PVC burden determined by 24 h Holter ECG during follow-up. Overall, 218 patients were enrolled (median age 52 years, 51% males). Baseline and procedural data were similar in the standard ablation (24%) and the CF-sensing group (76%). Overall, the median PVC burden decreased from 21% (IQR 10-30%) before ablation to 0.2% (IQR 0-3.0%) after a median follow-up of 2.3 months (IQR 1.4-3.9 months). The rates of both acute (91% vs. 91%, P = 0.94) and sustained success (79% vs. 74%, P = 0.44) were similar in the standard ablation and the CF-sensing groups. No differences were observed in subgroups according to arrhythmia origin from the RVOT (65%) or LVOT (35%). Complications were rare (1.8%) and evenly distributed between the two groups.

CONCLUSION

The use of CF-sensing technology is not associated with increased success rate nor decreased complication rate in idiopathic outflow tract PVC ablation.

Automatic reconstruction of the left atrium activation from sparse intracardiac contact recordings by inverse estimate of fibre structure and anisotropic conduction in a patient-specific model

AIMS

Electric conduction in the atria is direction-dependent, being faster in fibre direction, and possibly heterogeneous due to structural remodelling. Intracardiac recordings of atrial activation may convey such information, but only with high-quality data. The aim of this study was to apply a patient-specific approach to enable such assessment even when data are scarce, noisy, and incomplete.

METHODS AND RESULTS

Contact intracardiac recordings in the left atrium from nine patients who underwent ablation therapy were collected before pulmonary veins isolation and retrospectively included in the study. The Personalized Inverse Eikonal Model from cardiac Electro-Anatomical Maps (PIEMAP), previously developed, has been used to reconstruct the conductivity tensor from sparse recordings of the activation. Regional fibre direction and conduction velocity were estimated from the fitted conductivity tensor and extensively cross-validated by clustered and sparse data removal. Electrical conductivity was successfully reconstructed in all patients. Cross-validation with respect to the measurements was excellent in seven patients (Pearson correlation r > 0.93) and modest in two patients (r = 0.62 and r = 0.74). Bland-Altman analysis showed a neglectable bias with respect to the measurements and the limit-of-agreement at -22.2 and 23.0 ms. Conduction velocity in the fibre direction was 82 ± 25 cm/s, whereas cross-fibre velocity was 46 ± 7 cm/s. Anisotropic ratio was 1.91±0.16. No significant inter-patient variability was observed. Personalized Inverse Eikonal model from cardiac Electro-Anatomical Maps correctly predicted activation times in late regions in all patients (r = 0.88) and was robust to a sparser dataset (r = 0.95).

CONCLUSION

Personalized Inverse Eikonal model from cardiac Electro-Anatomical Maps offers a novel approach to extrapolate the activation in unmapped regions and to assess conduction properties of the atria. It could be seamlessly integrated into existing electro-anatomic mapping systems. Personalized Inverse Eikonal model from cardiac Electro-Anatomical Maps also enables personalization of cardiac electrophysiology models.

Optimized implementation of cardiac resynchronization therapy: a call for action for referral and optimization of care

Cardiac resynchronization therapy (CRT) is one of the most effective therapies for heart failure with reduced ejection fraction and leads to improved quality of life, reductions in heart failure hospitalization rates and all-cause mortality. Nevertheless, up to two-thirds of eligible patients are not referred for CRT. Furthermore, post-implantation follow-up is often fragmented and suboptimal, hampering the potential maximal treatment effect. This joint position statement from three European Society of Cardiology Associations, Heart Failure Association (HFA), European Heart Rhythm Association (EHRA) and European Association of Cardiovascular Imaging (EACVI), focuses on optimized implementation of CRT. We offer theoretical and practical strategies to achieve more comprehensive CRT referral and post-procedural care by focusing on four actionable domains: (i) overcoming CRT under-utilization, (ii) better understanding of pre-implant characteristics, (iii) abandoning the term 'non-response' and replacing this by the concept of disease modification, and (iv) implementing a dedicated post-implant CRT care pathway.

Patient voluntarily delays call to emergency medical system for ST-elevation myocardial infarction during COVID-19 pandemic

BACKGROUND

An increase in the time from the symptoms onset to first medical contact and to primary percutaneous coronary intervention (pPCI) has been observed in countries with high-incidence of COVID-19 cases. We aimed to verify if there was any change in the patient delay and in the EMS response times up to the pPCI for STEMI patients in Swiss Ticino Canton.

METHODS

We assessed STEMI management including time from symptoms onset to EMS call, time of EMS response, time to pPCI in Swiss Canton Ticino. Data were retrieved from the Acute-Coronary-Syndrome-Ticino-Registry. We considered the patients included in the registry from March to May 2020 (pandemic period) and then from June to August 2020 (post-pandemic period) in whom a pPCI was performed. We compared these patients to those undergoing a pPCI in the same months in the year 2016-2019.

RESULTS

During the pandemic period, the time from symptoms onset to pPCI significantly increased compared to non-pandemic periods. This was due to a significant prolongation of the time from symptoms onset to EMS call, that nearly tripled. In contrast, after the pandemic period, there was a significantly shorter time from symptom onset to EMS call compared to non-pandemic years, whereas all other times remained unchanged.

CONCLUSION

Patients delay the call to EMS despite symptoms of myocardial infarction during the COVID-19 pandemic also in a region with a relatively low incidence of COVID-19.

Leadless left ventricular endocardial pacing for CRT upgrades in previously failed and high-risk patients in comparison with coronary sinus CRT upgrades

AIMS

Cardiac resynchronization therapy (CRT) upgrades may be less likely to improve following intervention. Leadless left ventricular (LV) endocardial pacing has been used for patients with previously failed CRT or high-risk upgrades. We compared procedural and long-term outcomes in patients undergoing coronary sinus (CS) CRT upgrades with high-risk and previously failed CRT upgrades undergoing LV endocardial upgrades.

METHOD AND RESULTS

Prospective consecutive CS upgrades between 2015 and 2019 were compared with those undergoing WiSE-CRT implantation. Cardiac resynchronization therapy response at 6 months was defined as improvement in clinical composite score (CCS) and a reduction in LV end-systolic volume (LVESV) ≥15%. A total of 225 patients were analysed; 121 CS and 104 endocardial upgrades. Patients receiving WiSE-CRT tended to have more comorbidities and were more likely to have previous cardiac surgery (30.9% vs. 16.5%; P = 0.012), hypertension (59.2% vs. 34.7%; P < 0.001), chronic obstructive airways disease (19.4% vs. 9.9%; P = 0.046), and chronic kidney disease (46.4% vs. 21.5%; P < 0.01) but similar LV ejection fraction (30.0 ± 8.3% vs. 29.5 ± 8.6%; P = 0.678). WiSE-CRT upgrades were successful in 97.1% with procedure-related mortality in 1.9%. Coronary sinus upgrades were successful in 97.5% of cases with a 2.5% rate of CS dissection and 5.6% lead malfunction/displacement. At 6 months, 91 WiSE-CRT upgrades and 107 CS upgrades had similar improvements in CCS (76.3% vs. 68.5%; P = 0.210) and reduction in LVESV ≥15% (54.2% vs. 56.3%; P = 0.835).

CONCLUSION

Despite prior failed upgrades and high-risk patients with more comorbidities, WiSE-CRT upgrades had high rates of procedural success and similar improvements in CCS and LV remodelling with CS upgrades.

Swiss National Registry on Catheter Ablation Procedures: Changing Trends over the Last 20 Years

The Swiss Ablation Registry provides a national database for electrophysiologic studies and catheter ablations. We analyzed the database to provide an in-depth look at changing trends over the last 20 years. During the study period a total of 78622 catheter ablations (age 61.0 ± 1.2 years; 63.7% male) were performed in 29 centers. The number of ablations increased by approximately ten-fold in 20 years. Ablation for atrial fibrillation (AF) was the main driver behind this increase, with more than hundred-fold (39.7% of all ablations in 2019). Atrioventricular-nodal-reentrant-tachycardia (AVNRT) and accessory pathways, being the main indications for ablation in 2000 (44.1%/25.1%, respectively), made up of only a small proportion (15.2%/3.5%,) respectively in 2019. Fluoroscopy, ablation, and procedure durations were reduced for all ablations over time. The highest repeat ablations were performed for ventricular tachycardia and AF (24.4%/24.3%). The majority of ablations (63.0%) are currently performed in private hospitals and non-university public hospitals whereas university hospitals had dominated (82.4%) at the turn of the century. A pronounced increase in the number of catheter ablations in Switzerland was accompanied by a marked decrease in fluoroscopy, ablation, and procedure durations. We observed a shift toward more complex procedures in older patients with comorbidities.

The cost of non-response to cardiac resynchronization therapy: characterizing heart failure events following cardiac resynchronization therapy

AIMS

The aim of this study is to quantify healthcare resource utilization among non-responders to cardiac resynchronization therapy (CRT-NR) by heart failure (HF) events and influence of comorbidities.

METHODS AND RESULTS

The ADVANCE CRT registry (2013-2015) prospectively identified responders/CRT-NRs 6 months post-implant using the clinical composite score. Heart failure event rates and associated cost, both overall and separated for inpatient hospitalizations, office visits, emergency room visits, and observational stays, were quantified. Costs of events were imputed from payments for similar real-world encounters in subjects with CRT-D/P devices in the MarketScan™ commercial and Medicare Supplemental insurance claims databases. Effects of patient demographics and comorbidities on event rates and cost were evaluated. Of 879 US patients (age 69 ± 11 years, 29% female, ischaemic disease 52%), 310 (35%) were CRT-NR. Among CRT-NRs vs. responders, more patients developed HF (41% vs. 11%, P < 0.001), HF event rate was higher (67.0 ± 21.7 vs. 11.4 ± 3.7/100 pt-year, P < 0.001), and HF readmission within 30 days was more common [hazard ratio 7.06, 95% confidence interval (2.1-43.7)]. Inpatient hospitalization was the most common and most expensive event type in CRT-NR. Comorbid HF was increased by diabetes, hypertension, and pulmonary disorders. Over 2 years, compared to CRT responders, each CRT-NR resulted in excess cost of $6388 ($3859-$10 483) to Medicare (P = 0.015) or $10 197 ($6161-$17 394) to private insurances (P = 0.014).

CONCLUSION

Healthcare expenditures associated with contemporary CRT non-response management are among the highest for any HF patient group. This illustrates an unmet need for interventions to improve HF outcomes and reduce costs among some CRT recipients.