The role of the autonomous nervous system in atrial fibrillation progression. Data from the RACE V study

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): We acknowledge the support from the Netherlands Cardiovascular Research Initiative: an initiative with support of the Dutch Heart Foundation, CVON 2014-9: Reappraisal of Atrial Fibrillation: interaction between hyperCoagulability, Electrical remodelling, and Vascular destabilisation in the progression of AF (RACE V). Unrestricted grant support from Medtronic Trading NL B.V.

Background

Atrial fibrillation (AF) progression is associated with adverse outcome.

The autonomic nervous system plays a yet unsettled role in initiation and progression of AF.

Purpose

To assess in patients with paroxysmal selfterminating AF differences in phenotype and AF progression depending on the role of the autonomic nervous system in triggering AF episodes.

Methods

Patients with paroxysmal AF included in the Reappraisal of AF: Interaction Between HyperCoagulability, Electrical Remodelling, and Vascular Destabilisation in the Progression of AF (RACE V) study were analysed. Patients were extensively phenotyped at baseline and received continuous rhythm monitoring with an implantable loop recorder (ILR).To adequately define the role of the autonomic nervous system in triggering AF only patients with at least 3 selfterminating AF episodes were included. ILR data were used to assess whether AF was mainly vagally induced (>80% of episodes starting during night time) or mainly adrenergically induced (>80% starting during daytime), and to assess the development of AF progression. If a patient could not be identified as either vagal or adrenergic, they were classified as mixed AF. Primary outcome were differences in AF progression between the three groups. AF progression was defined as (1) progression to persistent or permanent AF, or (2) progression of PAF with >3% burden increase. Follow-up was 2.2 (1.6-2.8) years.

Results

278 patients were included, median was age 66 (59-71) years, 117 (42%) were women (Table 1). Patients with vagally or adrenergically induced AF had less comorbidities compared to mixed AF patients (median 2 versus 2 versus 3, respectively, p=0.012). In the mixed group, compared to either the vagal or adrenergic group the estimated glomerular filtration rate was slightly worse (median 78 versus 84 versus 82 mL/min*1.73m2 in the mixed versus vagal and adrenergic group, respectively, p=0.018), diabetes was more common (12% versus 5% versus 0%, respectively, p=0.031). Obesity was most often present in the vagal group (38% versus 12% versus 27%, in the vagal versus adrenergic versus mixed group, respectively p=0.028). Progression rates in the vagal versus adrenergic versus mixed groups were 5% versus 5% versus 24%, respectively (p=0.013 vagal versus mixed and p=0.008 adrenergic versus mixed group, respectively)(Figure).

Conclusion

Important differences exist between AF patients depending on their autonomic nervous system associated triggering mechanisms. Patients with either vagally or adrenergically induced AF have less comorbidities as compared to those with a mixed initiation type of AF and showed lower AF progression rates.

Adherence to mobile health for intermittent rhythm monitoring to detect recurrences after emergency department visit for recent-onset atrial fibrillation: a subanalysis of the RACE 7 ACWAS trial

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Netherlands Organization for Health Research and Development–Health Care Efficiency Research Program

Introduction

In the Rate Control versus Electrical Cardioversion Trial 7–Acute Cardioversion versus Wait and See (RACE 7 ACWAS) trial an early cardioversion approach was compared to a delayed cardioversion approach for patients with recent-onset symptomatic atrial fibrillation (AF), followed by a four-week monitoring period using mobile health (mHealth).

Purpose

To evaluate the adherence and motivation to a four-week mHealth prescription to daily intermittent rhythm monitoring for recurrences after emergency department visit in patients with recent-onset AF. In addition, we studied predictors of mHealth adherence and motivation and evaluated whether recurrences during this four-week period influenced adherence and motivation patterns.

Methods

After the index visit, patients were asked to use an electrocardiographic-based telemetric device to record one minute heart rate and rhythm recordings three times daily and in case of symptoms during a period of four weeks. For patients who collected recordings for more than four weeks, data was censored at four weeks. Adherence and patient motivation based on the number of monitoring days and full monitoring days were evaluated. A p-value of <0.05 was considered statistically significant.

Results

335 patients (58% men; median age 67±11 years) used the telemetric device and were included in the current analysis. The median overall adherence of all patients was 83.3% (IQR 29.9%). The median number of monitoring days was 27 (5), whereas the median number of full monitoring days was 16 (14). Age and the index episode being a recurrent paroxysm of AF rather than a first presentation were identified as independent predictors of adherence (odds ratio (OR) 1.037 (95%CI 1.015-1.060), p=0.001 and OR 1.863 (95%CI 1.190-2.916), p=0.007, respectively). Age (OR 1.031 (95%CI 1.009-1.053), p=0.005) and the use of antiarrhythmic drugs (OR 1.800 (95%CI 1.047-3.093), p=0.033) were identified as independent predictors of motivation. Patients with recurrences had significantly higher median adherence (87.7% vs 81.5%, p=0.028) and more full monitoring days (18 (14) days vs 15 (13) days, p=0.024), and were more likely to perform additional recordings (78.8% vs 49.2%, p=<0.001) compared to patients without recurrences.

Conclusion

Patients with recent-onset AF showed good adherence and motivation to a four-week mHealth prescription to monitor for AF recurrences after an emergency department visit for recent-onset AF. Adherence and motivation were high during the entire monitoring period, indicating that intermittent rhythm monitoring using mHealth is feasible for 1 month. Whether comparable mHealth adherence and motivation can be achieved in real world clinical scenarios outside a randomized study, warrants further observational studies.

Mobile app-based symptom-rhythm correlation assessment in patients with persistent atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

In patients with persistent atrial fibrillation (AF) it is difficult to determine the association between patient self-reported symptoms and the underlying heart rhythm (symptom-rhythm correlation [SRC]). No standardized strategy to assess SRC in AF patients is available.

Purpose

We assessed for the first time SRC in persistent AF patients using a mobile health approach of simultaneous photoplethysmography (PPG)-based rhythm monitoring and active interrogation of patient-reported symptoms, which provides a novel approach to systematically assess SRC in persistent AF.

Methods

Consecutive persistent AF patients planned for electrical cardioversion (ECV) used a mobile app to record a 60-second PPG and report symptoms once daily and in case of symptoms for four weeks prior and three weeks after ECV. Within each patient, SRC was quantified by the SRC-index defined as the sum of symptomatic AF recordings and asymptomatic non-AF recordings divided by the sum of all recordings.

Results

Of 88 patients (33% female, age 68±9 years) included, 78% reported any symptoms during recordings. The overall SRC-index was 0.61 (0.44-0.79). The study population was divided into SRC-index tertiles: low (<0.47), medium (0.47-0.73) and high (≥0.73). Patients within the low (vs high) SRC-index tertile had more often heart failure and diabetes mellitus (both 24.1% vs 6.9%). Extrasystoles occurred in 19% of all symptomatic non-AF PPG recordings. Within each patient, PPG recordings with the highest (vs lowest) tertile of pulse rates conferred an increased risk for symptomatic AF recordings (odds ratio [OR] 1.26, 95% coincidence interval [CI] 1.04-1.52) and symptomatic non-AF recordings (OR 2.93, 95% CI 2.16-3.97). Pulse variability was not associated with reported symptoms.

Conclusion

In persistent AF patients, simultaneous mobile app-based symptom and rhythm monitoring revealed a relatively low overall SRC, suggesting that the majority of patients experienced symptoms irrespective of AF. Extrasystoles can explain a minority of symptomatic non-AF PPG recordings. Pulse rate, but not pulse variability, is the main determinant of reported symptoms during AF and non-AF PPG recordings. Further studies are required to test whether mobile app-based SRC assessment can be implemented in current workflows and integrated into a personalized symptom and rhythm control AF management approach.

Advanced vascular aging in patients with paroxysmal atrial fibrillation - Data from RACE V

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Dutch Heart Foundation, Medtronic

Background

The incidence of atrial fibrillation (AF) increases exponentially with age. To which extend vascular aging is part of this process is unknown. Pulse wave velocity and carotid intima-media thickness are established markers for vascular aging and have been combined in a vascular aging index as published before(1).

Purpose

We aim to investigate if vascular age exceeds chronological age in our cohort with paroxysmal AF and if yes to which extend.

Methods

In this substudy from RACE V we included 295 patients with paroxysmal AF in which carotid-femoral pulse wave velocity (cfPWV) and carotid intima-media thickness (IMT) were measured. To calculate vascular aging we used a logarithmic formula derived from the Malmö-Cancer-and-Diet study which yields a vascular age index derived from cfPWV, cIMT and chronological age. This vascular aging index (VAI) is a strong predictor of cardiovascular events. (1). All patients underwent cardiac echocardiography and had a native cardiac CT scan in which fat around the heart and coronary calcium were quantified. In 121 patients Agatston scores from the ascending aortic artery were also measured.

Results

Patients in this study had a mean chronological age of 63.8 ± 10.1 years and a vascular age of 71.4 ± 11.7 years. Vascular age was on average 9.3 ± 10.2 years higher than chronological age. Vascular age correlated significantly with markers for diastolic dysfunction, vascular calcification in the coronary arteries as well as the aorta and the amount of epicardial and pericardial fat (table 1).

Conclusions

In patients with PAF vascular age was on average 9.3 years higher than chronological age in our cohort. Advanced vascular age is represented by vascular and myocardial remodeling related to fibrosis, calcification and fat accumulation. The results suggest that in patients with AF enhanced inflammation is leading to fibrosis and calcification. Whether AF is a marker, a mechanism or both in advanced vascular aging warrants further study.

The impact of different fat depots in the body on the progression of atrial fibrillation - data from RACE V

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Dutch Heart Foundation, Medtronic

Background

Paroxysmal atrial fibrillation (PAF) progression is associated with cardiovascular complications and worse outcome. Obesity is independently associated with AF prevalence and progression. The association between different fat depots in the body with AF is unclear.

Aim

We aim to systematically investigate the association of different fat depots in the body with AF.

Methods

417 patients with PAF and continuous rhythm monitoring (implantable loop recorder or pacemaker) were included in the prospective RACE V study. In addition to extensive phenotyping at baseline including calculating BMI and measuring waist circumference (WC) epicardial and pericardial fat were measured on non-contrast enhanced cardiac CT scans by tracing the pericardium manually on every slice and afterwards fat automatically summed between -50 and -150 HU. Epicardial fat was defined as fat within the pericardium, pericardial fat as fat inside the pericardium and adjacent to the pericardium and thoracic fat as adjacent fat outside the pericardium. AF progression was defined as (1) progression to persistent or permanent AF, or (2) progression of PAF with >3% burden increase within 2.2years of follow-up. Multivariable logistic regression analysis was used to analyse the association of different fat pads with AF progression.

Results

Six percent of patients per year showed AF progression (51/417) after a median follow-up of 2.2 (1.6-2.8) years. Multivariate analysis identified WC (odds ratio [OR] 1.03, 95% confidence intervals [CI] 1.01-1.06, p=.014) to be associated with AF progression. Epicardial fat (OR 1.00, 95%CI .99-1.01, p=.407), pericardial fat (OR 1.00, 95%CI .99-1.01, p=.311), thoracic fat (OR 1.00, 95%CI .99-1.01, p=.372), and BMI (OR 1.03, 95%CI .97-1.10, p=.328) showed no relation with AF progression.

Conclusion

AF progression occurred in 6% per year in patients with PAF. In contrast to epicardial, pericardial and thoracic fat measured in a semiautomatic way, WC was the only fat depot associated with AF progression. Whether a more different assessment of obesity and epicardial fat may demonstrate an association with AF progression warrants further study.

Atrial fibrillation detected at screening is not a benign condition - a comparison of clinical outcomes in screen-detected vs. hospital-detected atrial fibrillation

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Dutch Heart Foundation

Background

Screening for atrial fibrillation (AF) improves detection of AF. However, it is unknown whether AF detected at screening carries risks similar to clinically detected AF, and if it should be treated similarly.

Purpose

We aimed to compare clinical outcomes in individuals with screen-detected vs. hospital-detected incident AF.

Methods

We studied 8265 individuals (mean age 49 ± 13 years, 50% women) without prevalent AF from the population-based PREVEND (Prevention of Renal and Vascular End-Stage Disease) cohort study. By design, 70% of PREVEND participants had urinary albumin concentration ≥10 mg/l. AF was considered screen-detected when first detected on a 12-lead electrocardiogram (ECG) during one of the PREVEND study visits, and hospital-detected when first detected on a hospital ECG. Using Cox regression models with screen-detected and hospital-detected AF as time-varying covariates, we studied the association of screen-detected vs. hospital-detected AF with mortality, incident heart failure (HF), and incident cardiovascular (CV) events.

Results

During a mean follow-up of 9.7 years, 265 participants (3.2%) developed incident AF (mean age 62 ± 9 years, 30% women, 65% hypertension, 23% obesity, 9% diabetes, 15% history of myocardial infarction, 3% history of stroke, 2% prevalent HF). Of all incident AF cases, 60 (23%) were screen-detected and 205 (77%) hospital-detected. Baseline characteristics were generally comparable between participants with screen-detected and hospital-detected AF. A larger proportion of incident AF was screen-detected in men (26%) compared to women (15%). In univariabe analysis, both screen-detected and hospital-detected AF were strongly associated with death, incident HF, and incident CV events. After multivariable adjustment, hospital-detected AF was significantly associated with death (HR 2.95, 95% CI 2.18-4.00), incident HF (HR 3.98, 95% CI 2.49-6.34), and incident CV events (HR 1.92, 95% CI 1.21-3.06). Screen-detected AF was significantly associated with death (HR 2.21, 95% CI 1.09-4.47) and incident HF (HR 4.90, 95% CI 2.28-10.57), but not with incident CV events (HR 1.12, 95% CI 0.46-2.71).

Conclusions

In a population-based cohort enriched for microalbuminuria, almost a quarter of incident AF cases was first detected through ECG screening. Compared to hospital-detected AF, screen-detected AF was similarly associated with adverse outcomes. Although randomised trials are needed, this study highlights that AF screening may help decrease the general burden of CV disease.