Omega-3 fatty acids in adipose tissue and risk of atrial fibrillation

BACKGROUND

The aim of the present study was to examine the relation between adipose tissue content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the risk of incident atrial fibrillation (AF).

METHODS

In this case-cohort study based on data from the Danish Diet, Cancer and Health cohort, a total of 5255 incident cases of AF was identified during 16.9 years of follow-up. Adipose tissue biopsies collected at baseline from all cases and from a randomly drawn subcohort of 3440 participants were determined by gas chromatography. Data were analysed using weighted Cox regression.

RESULTS

Data were available for 4741 incident cases of AF (2920 men and 1821 women). Participants in the highest vs. the lowest quintile of EPA experienced a 45% lower risk of AF (men HR 0.55 (95% CI 0.41-0.69); women HR 0.55 (0.41-0.72)). For DHA, no clear association was found in men, whereas in women, participants in the highest quintile of DHA in adipose tissue had a 30% lower risk of incident AF (HR 0.70 (0.54-0.91)) compared to participants in the lowest quintile.

CONCLUSIONS

A monotonous inverse association was found for the content of EPA in adipose tissue and risk of AF in both men and women. The content of DHA was inversely associated with the risk of AF in women, whereas no clear association was found for men.

Non-Persistence with Medication as a Mediator for the Social Inequality in Risk of Major Adverse Cardiovascular Events in Patients with Incident Acute Coronary Syndrome: A Nationwide Cohort Study

Aim

Low socioeconomic status is associated with higher risk of major adverse cardiovascular events (MACE) among patients with incident acute coronary syndrome (ACS). We examined whether non-persistence with antiplatelet and statin therapy mediated the income- and educational-related inequality in risk of MACE.

Methods

Using national registers, all Danish patients diagnosed with incident ACS from 2010 to 2017 were identified. The primary outcome (MACE) comprised all-cause death, cardiac death and cardiac readmission. Risk of MACE was handled by discrete time analyses using inverse probability of treatment weights. The mediator variable comprised non-persistence to a combined 2-dimensional measure of statin and antiplatelet treatment. The mediation analysis was evaluated by population average effects.

Results

The study population was 45,874 patients, of whom 16,958 (37.0%) were non-persistent with medication and 16,365 (35.7%) suffered MACE during the median follow-up of 3.5 years. Compared to patients with low income, the adjusted hazard ratio of MACE was lowered by 33% (HR: 0.67, 95% CI: 0.61–0.72) in men and by 34% (HR: 0.66, 95% CI: 0.61–0.72) in women with high income, respectively. Similar results were observed according to level of education. A socioeconomic difference in risk of non-persistence was found in men but not women and only in relation to income. The lower risk of non-persistence observed in high-income men mediated the lower risk of MACE by 12.6% (95% CI: 11.1–14.1%) compared with low-income men.

Conclusion

Non-persistence with medication mediated some of the income-related inequality in risk of MACE in men, but not women, with incident ACS.

Mortality and ventricular arrhythmia after acute myocarditis: a nationwide registry-based follow-up study

Objective

Incidence and severity of acute myocarditis vary significantly in previous reports and there is a lack of epidemiological studies on the short-term risks of mortality, heart failure and ventricular arrhythmias in patients with acute myocarditis. Therefore, study aims were to examine 90-day risks of mortality, heart failure (HF) and ventricular arrhythmias in patients with acute myocarditis in comparison to age-matched and sex-matched background population controls.

Methods

In this nationwide register-based follow-up study of patients hospitalised with myocarditis between 2002 and 2018 in Denmark, 90-day risks of all-cause mortality, HF, ventricular arrhythmias (ventricular tachycardia, ventricular fibrillation (VF)), cardiac arrest and implantable cardioverter-defibrillator (ICD) implantation were compared with age-matched and sex-matched controls from the background population (1:5 matching). Absolute risks standardised to the age, sex and comorbidity distribution of the entire study population were derived from multivariable Cox regression.

Results

A total of 2523 patients hospitalised with myocarditis were included. Median age was 48 years (Q1–Q3: 30–69) and 67.7% were men. Comorbidity burden was more pronounced among patients with myocarditis relative to controls. Standardised 90-day all-cause mortality risk was 4.9% for patients with acute myocarditis versus 0.3% for controls (p<0.001). Ninety-day standardised risks for other endpoints were 7.5% versus 0.1% for HF, 1.9% versus <0.1% for VF/VF/arrest risk and 1.6% versus <0.1% for ICD implantation (all p<0.001).

Conclusions

In this large nationwide register-based follow-up study, patients hospitalised with myocarditis had significantly higher 90-day risks of all-cause mortality, HF, ventricular arrhythmias, cardiac arrest and ICD implantation compared with background population controls.

New onset anxiety and depression in patients with an implantable cardioverter defibrillator during 24 months of follow-up (data from the national DEFIB-WOMEN study)

OBJECTIVE

To examine the cumulative incidence of and covariates' association with new onset anxiety and depression in implantable cardioverter defibrillator (ICD) patients during 24 months of follow-up in patients without depression and anxiety at implant.

METHODS

Patients (n = 1040; 155 (14.9%) women; mean age: 64.2 ± 10.6) with a first-time ICD enrolled in the national, multi-center prospective observational DEFIB-WOMEN study comprised the study cohort. We obtained information on demographic and clinical data from the Danish Pacemaker and ICD Register.

RESULTS

During 24 months of follow-up, 138 (14.5%) patients developed new onset anxiety and 109 (11.3%) new onset depression. Age ≥ 60 [HR:0.60;95%CI:0.40-0.90] and an anxiety score between 3 and 4 [HR:2.85; 95%CI:1.71-4.75] and 5-7 [HR:5.97; 95%CI:3.77-9.45] on the Hospital Anxiety and Depression Scale (HADS) were associated with different hazards of new onset anxiety during follow-up. Age ≥ 60 [HR:0.62;95%CI:0.42-0.93] and a HADS depression score between 3 and 4 [HR:2.99;95%CI:1.80-4.95] and 5-7 [HR:6.45; 95%CI:4.12-10.10] were associated with different hazards of new onset depression.

CONCLUSION

During 24 months of follow-up, respectively 14.5% and 11.3% of patients developed new onset anxiety and depression, suggesting that screening patients at several timepoints, and in particular those with even minimally elevated HADS scores at baseline, may be warranted to identify patients at risk for poor health outcomes.

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.

Long-term follow-up of abandoned transvenous defibrillator leads: a nationwide cohort study

AIMS

Commonly, a dysfunctional defibrillator lead is abandoned and a new lead is implanted. Long-term follow-up data on abandoned leads are sparse. We aimed to investigate the incidence and reasons for extraction of abandoned defibrillator leads in a nationwide cohort and to describe extraction procedure-related complications.

METHODS AND RESULTS

All abandoned transvenous defibrillator leads were identified in the Danish Pacemaker and ICD Register from 1991 to 2019. The event-free survival of abandoned defibrillator leads was studied, and medical records of patients with interventions on abandoned defibrillator leads were audited for procedure-related data. We identified 740 abandoned defibrillator leads. Meantime from implantation to abandonment was 7.2 ± 3.8 years with mean patient age at abandonment of 66.5 ± 13.7 years. During a mean follow-up after abandonment of 4.4 ± 3.1 years, 65 (8.8%) abandoned defibrillator leads were extracted. Most frequent reason for extraction was infection (pocket and systemic) in 41 (63%) patients. Procedural outcome after lead extraction was clinical success in 63 (97%) patients. Minor complications occurred in 3 (5%) patients, and major complications in 1 (2%) patient. No patient died from complication to the procedure during 30-day follow-up after extraction.

CONCLUSION

More than 90% of abandoned defibrillator leads do not need to be extracted during long-term follow-up. The most common indication for extraction is infection. Abandoned defibrillator leads can be extracted with high clinical success rate and low risk of major complications at high-volume centres.

Anxiety and depression symptoms in Danish patients with an implantable cardioverter-defibrillator: prevalence and association with indication and sex up to 2 years of follow-up (data from the national DEFIB-WOMEN study)

AIMS

To investigate (i) the prevalence of anxiety and depression and (ii) the association between indication for implantable cardioverter-defibrillator (ICD) implantation and sex in relation to anxiety and depression up to 24 months' follow-up.

METHODS AND RESULTS

Patients with a first-time ICD, participating in the national, multi-centre, prospective DEFIB-WOMEN study (n = 1496; 18% women) completed the Hospital Anxiety and Depression Scale at baseline, 3, 6, 12, and 24 months. Data were analysed using linear mixed modelling for longitudinal data. Patients with a secondary prophylactic indication (SPI) had higher mean anxiety scores than patients with a primary prophylactic indication (PPI) at baseline, 3, and 12 months and higher mean depression scores at all-time points, except at 24 months. Women had higher mean anxiety scores as compared to men at all-time points; however, only higher mean depression scores at baseline. Overall, women with SPI had higher anxiety and depression symptom scores than men with SPI. Symptoms decreased over time in both women and men. From baseline to follow-up, the prevalence of anxiety (score ≥8) was highest in patients with SPI (13.3-20.2%) as compared to patients with PPI (range 10.0-14.7%). The prevalence of depression was stable over the follow-up period in both groups (range 8.5-11.1%).

CONCLUSION

Patients with a SPI reported higher anxiety and depression scores as compared to patients with PPI. Women reported higher anxiety scores than men, but only higher depression scores at baseline. Women with SPI reported the highest anxiety and depression scores overall.

Socioeconomic inequality in oral anticoagulation therapy initiation in patients with atrial fibrillation with high risk of stroke: a register-based observational study

OBJECTIVE

The study aimed to examine the association between socioeconomic factors (SEFs) and oral anticoagulation (OAC) therapy and whether it was influenced by changing guidelines. We hypothesised that inequities in initiation of OAC reduced over time as more detailed and explicit clinical guidelines were issued.

DESIGN

Register-based observational study.

SETTINGS

All Danish patients with an incident hospital diagnosis of atrial fibrillation (AF), aged ≥30 years old and with high risk of stroke from 1 May 1999 to 2 October 2015 were included. Absolute risk differences (RD) (95% CI) were used to measure the association.

PARTICIPANTS

154 448 patients (mean age 78.2 years, men 47.3%).

EXPOSURE

Education, family income and cohabiting status were the SEFs used as exposure.

OUTCOME

A prescription of OAC within -30 to +90 days of baseline (incident AF).

RESULTS

During 2002-2007, the crude RD of initiation of OAC for men with high education was 14.9% (12.8 to 16.9). Inequality reduced when new guidelines were published, and in 2013-2016 the crude RD was 5.6% (3.5 to 7.7). After adjusting for age, the RD substantially reduced. The same pattern was seen for cohabiting status, while inequality was smaller and more constant for income.

CONCLUSION

Patients with low income, low education and living alone were associated with lower chance of being initiated with OAC. For education and cohabiting status, the crude difference reduced around 2011, when more detailed clinical guidelines were implemented in Denmark. Our results indicate that new guidelines might reduce inequality in OAC initiation and that new, high-cost drugs increase inequality.

Lower perception of pharmacological treatment increases risk of non-adherence to medication

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): The Danish Heart Foundation

Background

A large proportion of patients fail to reach optimal adherence to medication following incident ischemic heart disease (IHD) despite amble evidence of the beneficial effect of medication. Non-adherence to medication increases risk of disease-related adverse outcomes but none has explored how perception about pharmacological treatment detail on non-adherence using register-based follow-up data.

Purpose

To investigate the association between patients’ perception of pharmacological treatment and risk of non-initiation and non-adherence to medication in a population with incident IHD.

Methods

This cohort study followed 871 patients until 365 days after incident IHD. The study combined patient-reported survey data on perception about pharmacological treatment (categorised by ‘To a high level’, ‘To some level’, and ‘To a lesser level’) with register-based data on reimbursed prescription of cardiovascular medication (antithrombotics, statins, ACE-inhibitors/angiotensin receptor blockers, and β-blockers). Non-initiation was defined as no pick-up of medication in the first 180 days following incident IHD and analysed by Poisson regression. Two different measures evaluated non-adherence in patients initiating treatment: 1) proportion of days covered (PDC) analysed by Poisson regression, and 2) risk of discontinuation analysed by Cox proportional hazard regression. All analyses were adjusted for confounding variables (age, sex, ethnicity, income, educational level, civil status, occupation, charlson comorbidity index, supportive relatives, and individual consultation in medication) identified by directed acyclic graph and obtained from national registers and the survey. Item non-response was handled by multiple imputation and item consistency was evaluated by McDonalds omega.

Results

Lower perceptions about pharmacological treatment was associated with increased risk of non-initiation and non-adherence to medication irrespectively of drug class and adherence measure in the multiple adjusted analyses (please see figure illustrating results on antithrombotics). A dose-response relationship was observed both at 180- and 365-days of follow-up, but the steepest decline in adherence differed when comparing the two adherence measures (results not shown). Moderate internal consistency was found for the summed measure of perception (McDonalds omega = 0.67).

Conclusion

Lower perception of pharmacological treatment was associated with subsequent non-initiation and non-adherence to medication, irrespectively of measurement method and drug class.

Abstract Figure. Figre: Multiple adjusted analyses

Driving following defibrillator implantation: a nationwide register-linked survey study

AIMS

Patients are restricted from driving following implantable cardioverter defibrillator (ICD) implantation or shock. We sought to investigate how many patients are aware of, and adhere to, the driving restrictions, and what proportion experience an ICD shock or other cardiac symptoms while driving.

METHODS AND RESULTS

We performed a nationwide survey of all living Danish residents 18 years or older who received a first-time ICD between 2013 and 2016 (n = 3913) and linked their responses with nationwide registers. Of 2741 respondents (47% primary prevention, 83% male, median age 67 years), 2513 (92%) held a valid driver's license at ICD implantation, 175 (7%) of whom had a license for professional driving. Many drivers were unaware of driving restrictions: primary prevention 58%; secondary prevention 36%; post-appropriate shock 28%; professional drivers 55%. Almost all (94%) resumed non-professional driving after ICD implantation, more than one-third during the restricted period; 35% resumed professional driving. During a median follow-up of 2.3 years, 5 (0.2%) reported receiving an ICD shock while driving, one of which resulted in a traffic accident. The estimated risk of harm was 0.0002% per person-year.

CONCLUSION

In this nationwide study, many ICD patients were unaware of driving restrictions, and more than one third resumed driving during a driving restriction period. However, the rate of reported ICD shocks while driving was very low.

Socioeconomic differences in outcomes after hospital admission for atrial fibrillation or flutter

AIMS

To examine socioeconomic differences in care and outcomes in a 1-year period beginning 30 days after hospital discharge for first-time atrial fibrillation or flutter (AF) hospitalization.

METHODS AND RESULTS

This nationwide register-based follow-up cohort study investigated AF 30-day discharge survivors in Denmark during 2005-2014 and examined associations between patient's socioeconomic status (SES) and selected outcomes during a 1-year follow-up period beginning 30 days post-discharge after first-time hospitalization for AF. Patient SES was defined in four groups (lowest, second lowest, second highest, and highest) according to each patient's equivalized income. SES of the included 150 544 patients was: 27.7% lowest (n = 41 648), 28.1% second lowest (n = 42 321), 23.7% second highest (n = 35 656), and 20.5% highest (n = 30 919). Patients of lowest SES were older and more often women. Within 1-year follow-up, patients of lowest SES were less often rehospitalized or seen in outpatient clinics due to AF, or treated with cardioversion or ablation and were slightly more often diagnosed with stroke and heart failure (HF) and significantly more likely to die (16.1% vs. 14.9%, 11.3% and 8.1%). Hazard ratios for all-cause mortality were 0.64 (95% confidence interval 0.61-0.68) for highest vs. lowest SES, adjusted for CHA2DS2-VASc score, chronic obstructive pulmonary disease, rate- and rhythm-controlling drugs, and cohabitation status.

CONCLUSION

In 30-day survivors of first-time hospitalization due to AF, lowest SES is associated with increased 1-year all-cause and cardiovascular mortality and fewer cardioversions, ablations, readmissions, and outpatient contacts due to AF. Our findings indicate a need for socially differentiated rehabilitation following hospital discharge for first-time AF.

Discontinuation of oral anticoagulation and risk of stroke and death after ablation for typical atrial flutter: A nation-wide Danish cohort study

INTRODUCTION

Oral anticoagulation (OAC) is indicated for patients with atrial fibrillation (AF) and atrial flutter (AFL) with a CHA₂DS₂-VASc score ≥ 2 for men and ≥3 for women. This is regardless of successful catheter ablation for their arrhythmia. Studies have mainly focused on AF, and little is known regarding use of OAC in AFL patients following catheter ablation.

PURPOSE

To describe discontinuation of OAC in a national cohort of patients who have undergone first-time cavo-tricuspid isthmus ablation (CTIA) for AFL.

METHODS

We identified patients undergoing first-time CTIA during the period 2010-2016 using the Danish National Ablation Registry. Information on comorbidities and OAC use were gathered using the Danish National Patient Registry and the Danish National Prescription Registry. Patients were followed until March 1st, 2018.

RESULTS

We identified 2409 consecutive patients. Median age was 66 (IQR 58-72) years, and 1952 (81%) were men. During mean follow-up of 4 ± 1.7 years, 723 (30%) patients discontinued OAC. Patients discontinuing OAC were younger, had less comorbidity, and a lower CHA₂DS₂-VASc score. During follow-up, 252 (10%) patients died, and 112 (5%) patients had a stroke. Incidence of both these events increased with increasing age and CHA₂DS₂-VASc score. In adjusted analysis, we observed higher mortality (p < 0.0001) in patients discontinuing OAC, while stroke rate was not significantly higher (p = 0.21).

CONCLUSION

In this national cohort of patients who have undergone first-time CTIA, patients discontinuing OAC treatment were younger and had less comorbidities. Patients remain at elevated risk of death and stroke/TIA, increasing with their age and CHA₂DS₂-VASc score.

Temporal Incidence of Appropriate and Inappropriate Therapy and Mortality in Secondary Prevention ICD Patients by Cardiac Diagnosis

OBJECTIVES

This study sought to estimate the temporal development in rates and incidences of appropriate and inappropriate implantable cardioverter-defibrillator (ICD) therapy and shocks by cardiac diagnosis in a real-world population of patients with secondary prevention ICDs.

BACKGROUND

Data on cardiac diagnoses and temporal development of ICD therapies in patients with secondary prevention ICDs are limited.

METHODS

Patients (N = 4,587) with a secondary prevention ICD were identified from the Danish Pacemaker and ICD Register (January 1, 2007, to December 31, 2016) and linked to nationwide administrative registers. The outcome of appropriate and inappropriate ICD therapy and all-cause mortality were analyzed by annual event rates, cumulative incidence plots, and Cox regression models.

RESULTS

During a mean follow-up of 3.6 ± 2.4 years, 1,362 patients (30%) experienced appropriate ICD therapy (16.8% shocks), and 350 patients (7.6%) experienced inappropriate ICD therapy (4.6% shocks). From 2007 to 2016, there was a significant temporal reduction in both appropriate and inappropriate ICD therapy from 28.2 (95% confidence interval [CI]: 21.6 to 37.0) to 7.9 (95% CI: 6.8 to 9.1) and 10.0 (95% CI: 6.4 to 15.5) to 1.0 (95% CI: 0.7 to 1.5) per 100 person-years (p for trends <0.001). Multivariate Cox regression analyses showed that arrhythmogenic right ventricular cardiomyopathy was associated with the highest probability of appropriate ICD therapy (hazard ratio: 2.45; 95% CI: 1.77 to 3.39; p < 0.0001), whereas patients with hypertrophic cardiomyopathy had the lowest probability (hazard ratio: 0.62; 95% CI: 0.42 to 0.93; p = 0.0196) when compared to patients with ischemic heart disease.

CONCLUSIONS

In this nationwide real-life cohort of patients with secondary prevention ICDs, we observed a significant temporal decline in delivered appropriate and inappropriate shocks and ICD therapies in the last decade. A large proportion of patients still experienced ICD therapy but with significant differences by cardiac diagnosis.

Cardiac vagal tone as a novel screening tool to recognize asymptomatic cardiovascular autonomic neuropathy: Aspects of utility in type 1 diabetes

AIMS

To test the performance of the cardiac vagal tone (CVT) derived from a 5-minute ECG recording compared with the standardized cardiovascular autonomic reflex tests (CARTs).

METHODS

Cross-sectional study included 56 well-phenotyped adults with type 1 diabetes (19-71 years, 2-54 years disease-duration). Autonomic testing included: standardized CARTs obtained with the VAGUS™, CVT, and indices of heart rate variability (HRV) obtained at 24- and 120-hour, and electrochemical skin conductance assessed with SUDOSCAN®. ROC AUC and cut-off values were calculated for CVT to recognize CAN based on ≥ 2 (established CAN, n = 7) or 1 (borderline CAN, n = 9) abnormal CARTs and compared to HRV indices and electrochemical skin conductance.

RESULTS

Established CAN: The cut-off CVT value of 3.2LVS showed 67% sensitivity and 87% specificity (p = 0.01). Indices of HRV at either 24-hour (AUC > 0.90) and 120-hour (AUC > 0.88) performed better than CVT. Borderline CAN: The cut-off CVT value of 5.2LVS indicated 88% sensitivity and 63% specificity (p = 0.07). CVT performed better than HRV indices (AUC < 0.72). Electrochemical skin conductance (AUC:0.63-0.72) had lower sensitivity and specificity compared with CVT.

CONCLUSIONS

Implementation of CVT with a clinically applicable cut-off value may be considered a quicker and accessible screening tool which could ultimately decrease the number of unrecognized CAN and initiate earlier prevention initiatives.

Genome-wide association study of patients with atrioventricular nodal reentry tachycardia

Background

Supraventricular tachycardias (SVTs) originate from the atria or the area close to the AV node. AV nodal reentry tachycardia (AVNRT) is one of the tachyarrhytmias comprising the group of SVTs. The typical patient is female, young at disease onset, with a structurally normal heart. At present we do not know the etiology of AVNRT. We therefore hypothesized that AVNRT might be caused by changes in the DNA.

Methods

DNA from purified blood was obtained from patients with AVNRT verified by an invasive electrophysiological study. Patients were recruited from five ablation centers in Denmark and individuals from the general population of Denmark (the BEFUS cohort) served as controls. DNA was subjected to chip genotyping, imputation and analyses in a genome-wide association study (GWAS) setup.

Results

A GWAS on 1,143 AVNRT patients and 3,004 controls revealed one locus close to the gene MYH6 to reach genome-wide significance for association with AVNRT (P=4.8x10–8). MYH6 encodes the α-isoform of the protein myosin heavy chain important for the contractile units of the heart, the sarcomeres. The gene is predominantly expressed in the atria. Additional subthreshold loci located close to other plausible arrhythmia genes were identified.

Conclusion

We report the first genetic locus to be associated with AVNRT close to the sarcomere gene MYH6. This is, to our knowledge, the first gene ever associated with AVNRT.

Manhattan plot

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): Rigshospitalets Forskningspulje - 3 years PhD salary

863Leadless endocardial pacing improves symptoms in patients with failed conventional CRT implant in long term follow up

Funding Acknowledgements

EBR Systems, Inc

OnBehalf

WiSE-CRT and LV-SELECT study and POST-M REGISTRY

Background

The WiSE-CRT (Wireless stimulation endocardial) system has advantages over conventional epicardial CRT. Whenever conventional CRT failed to implant or failed to echocardiographic response, the WiSE-CRT was implanted as part of the WiSE CRT study (N = 13), as part of the LV-SELECT study (N = 35) or as part of the POST-M REGISTRY (N = 117) over the last 8 years. All these studies have reported high rates of clinical and echocardiographic response compared to conventional CRT.

Objectives

The purpose of this analysis was to determine the safety and clinical response in the largest available number of implanted patients (pts) with long term follow up of 2 years and the first, second and third generation of WiSE-CRT devices.

Method

All pts undergoing a WiSE-CRT implantation as part of the WiSE CRT study (N = 13), as part of the LV-SELECT study (N = 35) or as part of the POST-M REGISTRY (N = 117) were analysed (N = 165). Pts were followed-up for 24 months and considered CRT responders if an improvement in NYHA ≥ 1 class from baseline (pre-implant) was achieved.

Results

In total, 165 pts were implanted, demographics include: 68.2 ± 9.6 year’s old, 81.8% male, 49.7% with history of AFib and 54.5% non-ischaemic aetiology. The mean intrinsic QRS duration was 165.0 ± 32.3 msec (28 pts pace-maker dependent). 161 pts had the system successfully implanted with no major complications, 3 (1.8%) pts developed a pericardial effusion and 1 (0.6%) electrode was lost during implantation and recovered surgically. During the 24-month follow-up period, 20 (12.1%) pts died from any cause, 4 (2.4%) pts developed TIA or Stroke and 15 (9.1%) pts had pocket or transmitter infection. There was a significant improvement in NYHA functional class in 63.6% pts and an average improvement of -26.1 (-45.1, -7.1) msec in QRS duration.

Conclusion

Despite a history of failed conventional CRT implantation, pts undergoing CRT upgrades with a WiSE-CRT have a high success rate and a complication rate similar to previously described. In addition endocardial LV pacing led to symptomatic improvements in 64% of patients reaching the 24 month of follow up.

Abstract Figure 1: Forest Plot NYHA Responder Rat

P536Reverse remodeling after cardiac resynchronization therapy is associated with improvement of contractile asymmetry in the area of left ventricular lead position

Background

One third of patients receiving cardiac resynchronization therapy (CRT) do not respond to the treatment, possibly due to suboptimal lead position and persistent dyssynchronous left ventricular (LV) contraction.

Purpose

To assess the influence of LV lead position on improvement of contractile asymmetry and its significance for LV reverse remodeling after CRT.

Methods

Patients with heart failure and left bundle branch block undergoing CRT implantation were studied retrospectively. Assessment of mechanical delay within the LV was assessed using a recently developed index of contractile asymmetry (ICA). ICA was calculated as standard deviation of differences in systolic strain rate in the opposing LV walls derived from curved anatomical M-mode plots. LV was divided into 12 equally sized 30-degree sectors. Spline interpolation was used to estimate ICA in six opposing sector pairs permitting quantification of regional contractile asymmetry in the entire LV. Position of LV lead tip was assessed by thoracic computed tomography (CT). Response to CRT was defined as a reduction of LV end-systolic volume (ESV) ≥15% after 6 months.

Results

Study population (n= 26) consisted of 65.4% males, 68 ± 10 years, ischemic etiology in 42.3%, LV ejection fraction 24.1 ± 5.8%, QRS duration 171 ± 22 ms. CRT response was present in 18 (69.2%) patients. Pre-implantation ICA in the LV sector containing LV lead was 0.75 ± 0.24 s-1 in responders vs. 0.46 ± 0.16 s-1 in non-responders (p = 0.003). Reduction of ICA in the LV sector with LV lead was directly correlated with reduction of LV ESV after CRT (r = 0.46, p = 0.02) (Figure 1). ICA reduction in the LV sector with LV lead was -0.24 ± 0.28 s-1 in responders and -0.05 ± 0.16 s-1 in non-responders (p = 0.03). Meanwhile, reduction of ICA in the LV sectors located 60 degrees clockwise and 60 degrees counterclockwise away from the LV sector with LV lead (remote LV sectors) did not differ significantly between responders and non-responders: -0.12 ± 0.15 s-1 vs. -0.06 ± 0.1 s-1 (p = 0.28). Likewise, no significant correlation between reduction of ICA in remote LV sectors and LV ESV reduction was observed (p = 0.11).

Conclusion

Pre-implantation contractile asymmetry in the LV lead target area is associated with a positive response to CRT. Simultaneously, the degree of LV reverse remodeling after CRT seems to correlate with the magnitude of improvement of contractile asymmetry specifically in the region of LV lead location.

Abstract Figure 1

Leadless left ventricular endocardial pacing in nonresponders to conventional cardiac resynchronization therapy

BACKGROUND

Endocardial pacing may be beneficial in patients who fail to improve following conventional epicardial cardiac resynchronization therapy (CRT). The potential to pace anywhere inside the left ventricle thus avoiding myocardial scar and targeting the latest activating segments may be particularly important. The WiSE-CRT system (EBR systems, Sunnyvale, CA) reliably produces wireless, endocardial left ventricular (LV) pacing. The purpose of this analysis was to determine whether this system improved symptoms or led to LV remodeling in patients who were nonresponders to conventional CRT.

METHOD

An international, multicenter registry of patients who were nonresponders to conventional CRT and underwent implantation with the WiSE-CRT system was collected.

RESULTS

Twenty-two patients were included; 20 patients underwent successful implantation with confirmation of endocardial biventricular pacing and in 2 patients, there was a failure of electrode capture. Eighteen patients proceeded to 6-month follow-up; endocardial pacing resulted in a significant reduction in QRS duration compared with intrinsic QRS duration (26.6 ± 24.4 ms; P = .002) and improvement in left ventricular ejection fraction (LVEF) (4.7 ± 7.9%; P = .021). The mean reduction in left ventricular end-diastolic volume was 8.3 ± 42.3 cm³ (P = .458) and left ventricular end-systolic volume (LVESV) was 13.1 ± 44.3 cm³ (P = .271), which were statistically nonsignificant. Overall, 55.6% of patients had improvement in their clinical composite score and 66.7% had a reduction in LVESV ≥15% and/or absolute improvement in LVEF ≥5%.

CONCLUSION

Nonresponders to conventional CRT have few remaining treatment options. We have shown in this high-risk patient group that the WiSE-CRT system results in improvement in their clinical composite scores and leads to LV remodeling.

Influence of socioeconomic status on the referral process to cardiac rehabilitation following acute coronary syndrome: a cross-sectional study

OBJECTIVE

To evaluate the association between socioeconomic status (SES) and referral to cardiac rehabilitation (CR) after incident acute coronary syndrome (ACS) by dividing the referral process into three phases: (1) informed about CR, (2) willingness to participate in CR, (3) and assigned CR setting.

DESIGN

Cross-sectional study.

SETTING

Department of Cardiology at a Danish University Hospital from 1 January 2011 to 31 December 2014.

PARTICIPANTS

A total of 1229 patients assessed for CR during hospitalisation with ACS were prospectively registered in the Rehab-North Register from 2011 to 2014. SES was assessed using data from national registers, concerning: personal income, occupational status, educational level and civil status. Patients were excluded if one of the following criteria was fulfilled: (1) missing data on SES, or (2) acceptable reason for not informing patients about CR (treatment with coronary artery bypass grafting, transfer to another hospital, still under treatment or death).

MAIN OUTCOME MEASURES

Outcomes were defined by dividing the referral process into three phases: (1) informed about CR, (2) willingness to participate, and (3) assigned CR setting (in-hospital/community centre) after ACS.

RESULTS

A total of 854 (69.5 %) patients were referred to CR. After adjustment for age, gender, ACS diagnosis (ST-elevated myocardial infarction, non-ST-elevated myocardial infarction, unstable angina pectoris) and comorbidity, high income had the strongest association of referral to CR in all three phases (informed about CR: OR 2.17, 95% CI 1.01 to 4.64; willingness to participate in CR: OR 1.55, 95% CI 1.02 to 2.35; assigned in-hospital CR: OR 1.47, 95% CI 0.91 to 2.36). Educational level showed similar tendencies, however not statistically significant. The results did not vary according to gender.

CONCLUSION

This is the first study to investigate the referral process to CR using a three-phase structure. It suggests income and education to influence all phases in the referral process to CR after ACS.

Real-world experience of leadless left ventricular endocardial cardiac resynchronization therapy: A multicenter international registry of the WiSE-CRT pacing system

Background

Biventricular endocardial pacing (BiV ENDO) is a therapy for heart failure patients who cannot receive transvenous epicardial cardiac resynchronization therapy (CRT) or have not responded adequately to CRT. BiV ENDO CRT can be delivered by a new wireless LV ENDO pacing system (WiSE-CRT system; EBR Systems, Sunnyvale, CA), without the requirement for lifelong anticoagulation.

Objective

The purpose of this study was to assess the safety and efficacy of the WiSE-CRT system during real-world clinical use in an international registry.

Methods

Data were prospectively collected from 14 centers implanting the WiSE-CRT system as part of the WiCS-LV Post Market Surveillance Registry. (ClinicalTrials.gov Identifier: NCT02610673).

Results

Ninety patients from 14 European centers underwent implantation with the WiSE-CRT system. Patients were predominantly male, age 68.2 ± 10.5 years, left ventricular ejection fraction 30.6% ± 8.9%, mean QRS duration 180.7 ± 27.0 ms, and 40% with ischemic etiology. Successful implantation and delivery of BiV ENDO pacing was achieved in 94.4% of patients. Acute (<24 hours), 1- to 30-day, and 1- to 6-month complications rates were 4.4%, 18.8%, and 6.7%, respectively. Five deaths (5.6%) occurred within 6 months (3 procedure related). Seventy percent of patients had improvement in heart failure symptoms.

Conclusion

BiV ENDO pacing with the WiSE-CRT system seems to be technically feasible, with a high success rate. Three procedural deaths occurred during the study. Procedural complications mandate adequate operator training and implantation at centers with immediately available cardiothoracic and vascular surgical support.

Socioeconomic position and risk of atrial fibrillation: a nationwide Danish cohort study

AIM

To examine the association between socioeconomic position and the risk of atrial fibrillation (AF) in different stages of life in a population of Danish citizens.

METHODS

Register-based study. We followed all individuals turning 35, 50, 65 or 80 years from 1 January 1996 to 31 December 2005 until AF, death, emigration or the end of study period (31 December 2015). Exposure was education and income. We used Cox regression for the HRs (95% CI) and the pseudo-observation method for the adjusted risk difference (RD) (%).

RESULTS

A total of 2 173 857 participants were enrolled and 151 340 incident cases of AF occurred over a median of 13.6 years of follow-up. Adjusted HR (95% CI) of incident AF for the youngest age group with the highest education (ref lowest) was 0.62 (0.50 to 0.77) (women) and 0.85 (0.76 to 0.96) (men). The associations attenuated with increasing age, that is, HRs for the oldest age group were 1.04 (0.97 to 1.10) and 0.98 (0.96 to 1.04), respectively. The corresponding adjusted RDs (%) were: -0.28 (-0.43 to -0.14), -0.18 (-0.36 to -0.01), 3.04 (-0.55 to 6.64) and -0.74 (-3.38 to 2.49), respectively. Similar but weaker associations were found for income.

CONCLUSION

Higher level of education and income was associated with a lower risk of being diagnosed with AF in young individuals but the association decreased with increasing age and was almost absent for the oldest age cohort. However, since AF is relatively rare in the youngest the RDs were low.

5968Adherence to driving restrictions among patients with an implantable cardioverter defibrillator: insights from a nationwide register-linked survey study

Background

Patients with an implantable cardioverter defibrillator (ICD) are restricted from driving following initial implantation or ICD shock. It is unclear how many patients are aware of, and adhere to, these restrictions.

Purpose

To investigate knowledge of, and adherence to, private and professional driving restrictions in a nationwide cohort of ICD patients.

Methods

A questionnaire was distributed to all living Danish residents ≥18 years who received a first-time ICD between 2013 and 2016 (n=3,913). During this period, Danish guidelines recommended 1 week driving restriction following ICD implantation for primary prevention, and 3 months following either ICD implantation for secondary prevention or appropriate ICD shock, and permanent restriction of professional driving and driving of large vehicles (>3.5 metric tons). Questionnaires were linked with relevant nationwide registries. Logistic regression was applied to identify factors associated with non-adherence.

Results

Of 2,741 questionnaire respondents, 92% (n=2,513) held a valid private driver's license at time of ICD implantation (85% male; 46% primary prevention indication; median age: 67 years (IQR: 59–73)). Of these, 7% (n=175) were actively using a professional driver's license for truck driving (n=73), bus driving (n=45), taxi driving (n=22), large vehicle driving for private use (n=54), or other purposes (n=32) (multiple purposes allowed).

Only 42% of primary prevention patients, 63% of secondary prevention patients, and 72% of patients who experienced an appropriate ICD shock, recalled being informed of any driving restrictions. Only 45% of professional drivers recalled being informed about specific professional driving restrictions (Figure). Most patients (93%, n=2,344) resumed private driving after ICD implantation, more than 30% during the driving restriction period: 34% of primary prevention patients resumed driving within 1 week, 43% of secondary prevention patients resumed driving within 3 months, and 30% of patients who experienced an appropriate ICD shock resumed driving within 3 months. Professional driving was resumed by 35%. Patients who resumed driving within the restricted periods were less likely to report having received information about driving restrictions (all p<0.001) (Figure).

In a multiple logistic regression model, non-adherence was predicted by reporting non-receipt of information about driving restrictions (OR: 3.34, CI: 2.27–4.03), as well as male sex (OR: 1.53, CI: 1.17–2.01), age ≥60 years (OR: 1.20, CI: 1.02–1.64), receipt of a secondary prevention ICD (OR: 2.2, CI: 1.80–2.62), and being the only driver in the household (OR: 1.29, CI: 1.05–1.57).

Conclusion

In this nationwide survey study, many ICD patients were unaware of the driving restrictions, and many ICD patients, including professional drivers, resumed driving within the restricted periods. More focus on communicating driving restrictions might improve adherence.

Acknowledgement/Funding

Danish Heart Foundation, Arvid Nilsson Foundation, Fraenkels Mindefond