7-day Holter Monitoring Research Articles

C-reactive protein for prediction of atrial fibrillation recurrence after catheter ablation

BackgroundInflammation plays an important role in the initiation and progression of atrial fibrillation (AF), but data about the relationship between subclinical inflammation and recurrence of AF after catheter ablation remains poorly studied. We aimed to assess whether plasma levels of C-reactive protein (CRP) are associated with long-term AF recurrence following catheter ablation.MethodsPrior to the intervention, plasma CRP concentrations were measured in patients who underwent first catheter ablation for AF. AF recurrence was evaluated after 12 months and defined as any AF episode longer than 30 s recorded on either 12-lead electrocardiogram, 24-h Holter or 7-day Holter monitoring. Multivariable adjusted Cox models were constructed to examine the association of CRP levels and AF recurrence.ResultsOf the 711 patients (mean age: 61 years, 25% women) included in this study, 247 patients (35%) experienced AF recurrence after ablation. Patients who were in the highest CRP quartile had a higher rate of recurrent AF compared to those who were in the lowest quartile (53.4 vs. 33.1% at 1 year of follow-up; P = 0.004). The adjusted hazard ratios (aHR) of recurrent AF across increasing quartiles of CRP were 1.0 (reference), 1.26 (95% confidence interval [CI], 0.86–1.84), 1.15 (95% CI, 0.78–1.70) and 1.60 (95% CI, 1.10–2.34) (P trend = 0.015). A similar effect was observed when CRP was analyzed as continuous variable (aHR per unit increase, 1.21; 95% CI, 1.05–1.39; P = 0.009). When a predefined CRP cut-off of 3 mg/l was applied, patients with CRP levels of 3 mg/l or above had a higher risk of AF recurrence than those with levels below (aHR, 1.44; 95% CI, 1.06–1.95; P = 0.019).ConclusionsIncreasing pre-interventional CRP levels are associated with a higher risk of AF recurrence in patients undergoing catheter ablation for AF.Trail registrationClinicalTrials.gov identifier, NCT03718364.

Atrial Fibrillation After Ischemic Stroke Detected by Chest Strap-Style 7-Day Holter Monitoring and the Risk Predictors: EDUCATE-ESUS.

Aim: This study aimed to investigate the diagnostic yield of 7-day Holter monitoring for detecting covert atrial fibrillation (AF) in patients with recent embolic stroke of undetermined source (ESUS) and to identify the pre-entry screening biomarkers that had significant associations with later detection of AF (clinicaltrials.gov. NCT02801708). Methods: A total of 206 patients who have recent ESUS without previously documented AF underwent Holter electrocardiography using a chest strap-style monitor. External validation of biomarkers predictive of AF was performed using 83 patients with ESUS who were implanted with insertable cardiac monitors. Results: The 7-day Holter monitoring started at a median of 13 days after the onset of stroke. AF was detected in 14 patients, and three of these showed a single AF episode lasting ＜2 min. The median time delay to the first documented AF was 50 h. Each of serum brain natriuretic peptide ≥ 66.0 pg/mL (adjusted odds ratio 5.23), atrial premature contractions (APCs) ≥ 345 beats (3.80), and APC short runs ≥ 13 (5.74) on 24-h Holter prior to the 7-day Holter showed a significant association with detection of AF, independent of age and physiological findings in this derivation cohort, and all of these showed a significant association in the validation cohort (adjusted odds ratio 6.59, 7.87, and 6.16, respectively). Conclusions: In recent ESUS patients, the detection rate of AF using the 7-day Holter monitoring was 6.8% (95% CI 4.1%–11.1%). Brain natriuretic peptide, APC count, and APC short runs in the standard clinical workup seemed to be predictors of covert AF.

The value of the ablation index in patients undergoing ablation for atrial fibrillation.

Data on the results of ablation for atrial fibrillation (AF) in Poland are scarce. The aim of the study was to compare the efficacy of ablation index (AI)-guided pulmonary vein isolation (PVI) with that of conventional contact force-based PVI. Consecutive patients undergoing PVI for the first time were included in the study. A nonrandomized retrospective comparison was made between patients ablated with contact force before AI was introduced (non -AI group) and patients ablated with the use of AI (AI group). The AI threshold for the anterior wall / roof of left veins was 500 and 380 elsewhere. The maximal interlesion distance was 6 mm. The follow -up included outpatient visits and 7-day Holter monitoring 6 and 12 months after ablation. A total of 275 patients were included in the analysis: 133 in the AI group and 142 in the non--AI group. The duration of AF ablation was slightly longer in the AI group, but the fluoroscopy time and the radiofrequency ablation time were shorter in the same group. During the 12-month follow -up period, 25.8% and 40.6% of patients from the AI and non -AI groups, respectively, experienced recurrences (P = 0.02). The log -rank test with an extended follow -up period of up to 18 months confirmed the difference between the AI and non -AI groups, both in the whole group and in the paroxysmal AF and nonparoxysmal AF subgroups (P = 0.001, P = 0.04, and P = 0.006, respectively). The AI -based protocol provides a significant advantage over traditional contact force-based radiofrequency ablation in nonselected patients undergoing PVI.

Continuous electrocardiography for detecting atrial fibrillation beyond 1 year after stroke in primary care

Background and purposeThe diagnostic benefit of using continuous ECG (cECG) for poststroke atrial fibrillation (AF) screening in a primary care setting is unclear. We aimed to assess the diagnostic yield...

Thoracoscopic Left Atrial Appendage Excision Plus Ablation for Atrial Fibrillation to Prevent Stroke

Atrial fibrillation (AF) patients with a previous stroke are often at a high risk of recurrent stroke and bleeding. Anticoagulation therapy in such patients is a challenging dilemma. Thoracoscopic left atrial appendage excision (LAAE) plus AF ablation is an interventional approach offered to some AF patients. We hypothesized that this approach may be suitable as a secondary stroke prevention strategy for these high-risk patients. Between January 2013 and December 2016, a total of 44 patients (26 male; mean age 65.0 ± 9.1 years) with nonvalvular AF and a previous stroke or systemic thromboembolic event were enrolled. The patients underwent thoracoscopic LAAE plus AF ablation by experienced operators and were followed up for 2 years (at 1, 3, 6, 9, and 12 months postoperatively and every 6 months thereafter). Thromboembolic and major bleeding events were recorded. Cerebral computed tomography or magnetic resonance imaging and 7-day Holter monitoring were performed annually. Mean CHA2DS2-VASc and HAS-BLED scores were 4.2 ± 1.2 and 3.3 ± 0.7, respectively. All patients discontinued oral anticoagulation therapy after the surgical intervention. One patient suffered a periprocedural transient ischemic attack, and another was diagnosed with a new ischemic stroke at 491 days after surgery. The annual rate of total thromboembolism was 2.05%. No deaths or major bleeding events were observed postoperatively. The rate of successful AF ablation with no AF recurrence was 76.3%. Transthoracoscopic LAAE plus AF ablation may be a promising approach for this high-risk population. Thromboembolism event in this secondary prevention cohort was low, even without oral anticoagulation treatment.

P1816 Cerebral microembolism in low-risk patients with paroxysmal atrial fibrillation before and after pulmonary vein isolationCerebral microembolism in low-risk patients with paroxysmal atrial fibrillation

Abstract BACKGROUND Invasive treatment of atrial fibrillation (AF) becomes more suitable and effective therapy. There are no consistent data describing the occurrence of potential neurological complications in low-risk patients with paroxysmal AF. AIM to determine the occurrence, consequences and risk factors for brain white matter hiperintensities (WMH) assessed in magnetic resonance imaging (MRI) in low-risk patients before and after pulmonary vein isolation (PVI) treatment. METHODS Eighty patients with symptomatic paroxysmal AF (median age: 58 years (IQR 50-63), K/M: 30/50), CHA2DS2-Vasc ≤ 3 (CHA2DS2-Vasc: 2 (IQR 1-2.5)) were included in the study. Before and after a minimum of 6-month period after PVI-RF treatment (med. 9,9 months, IQR 7.6-11.8 months) a clinical evaluation with brain MRI and Mini Mental State Examination (MMSE) test were determined. Severity of brain WMH in MRI was assessed in the Fazekas scale (pic 1). The efficacy of PVI-RF treatment analyzed in a 7-day Holter monitoring was confirmed in 43 (53.8%) patients. RESULTS Baseline WMH lesions were found in 55 (68.8%) patients. Patients with baseline WMH lesion obtained similar results in the MMSE test, compared to patients with a normal brain image in the MRI study. There was a statistically significant more frequent occurrence of cerebral WMH lesions among older patients, with a higher CHA2DS2-Vasc score, with left atrial (LA) dilatation and dysfunction. Factors affecting the severity of the WMH were: the co-occurrence of the patent foramen ovale (PFO) and coronary artery disease (CAD). After PVI-RF treatment there were no significant changes in the presence and severity of WMH lesions. Similarly, there were no significant changes in the cognitive abilities assessed with MMSE test compared to the pre-procedural evaluation. There were also similar factors predisposing to brain WMH changes: older age, higher CHA2DS2-Vasc score and higher BMI. In turn, the degree of the brain WMH severity after observation period was dependent on age, higher CHA2DS2-Vasc score, presence of PFO and CAD and the initial LA function. CONCLUSIONS Cerebral microembolism assessed in MRI is often found in low-risk patients with paroxysmal AF, and its presence and severity are associated with LA dilatation and dysfunction, age and higher CHA2DS2-Vasc score. Additional factors affecting the severity of WMH lesions are: the co-occurrence of PFO and CAD. PVI-RF procedure and its efficacy does not influence on MRI lesions. In the population of relatively young AF patients with no significant cardiovascular disease burden, cerebral microembolism is not related to cognitive impairment. Abstract P1816 Figure. pic 1

Cryoballoon ablation for persistent atrial fibrillation in patients without left atrial fibrosis.

The role of cryoballoon (CB) pulmonary vein isolation (PVI) for patients with persistent atrial fibrillation (AF) is controversial, since long-term success can be poor. We performed left atrial voltage mapping before CB PVI and determined AF-free survival depending on the extent of low-voltage areas (LVAs). We consecutively enrolled 60 patients with persistent AF (average age, 60.6 ± 12.9 years; CHA2 DS 2 VASc score, 2.3 ± 1.6; and left atrial size 46.0 ± 5.2 mm) who were planned for CB PVI. Before ablation, we performed left atrial voltage mapping (Abbott EnSite Precision or Velocity). LVAs were defined if local bipolar signal amplitudes were less than 0.5 mV during sinus rhythm. Thirty-seven patients did not show significant LVAs (<10%), while 12 patients had LVAs between 10% and 30% and 11 patients showed substantial LVAs greater than 30% of the left atrial area. CB PVI could be successfully performed in all patients. A 7-day holter monitoring was obtained 3, 6, and 12 months after ablation. After a 12-month follow-up time, 83.8% of patients without LVAs (<10%) were free of atrial fibrillation, while 50.0% of patients with 10% to 30% LVAs and 9.1% of patients with LVAs more than 30% had stable sinus rhythm. The degree of atrial fibrosis correlated with the risk of AF recurrence. In patients with persistent AF undergoing CB PVI, the extent of left atrial LVAs predicts an AF-free survival. CB PVI seems to be a highly effective treatment for patients with persistent AF without atrial fibrosis.

Assessment of Myocardial Function in Kenyan Children With Severe, Acute Malnutrition

Mortality among African children hospitalized with severe malnutrition remains high, with sudden, unexpected deaths leading to speculation about potential cardiac causes. Malnutrition is considered high risk for cardiac failure, but evidence is limited. To investigate the role of cardiovascular dysfunction in African children with severe, acute malnutrition (SAM). A prospective, matched case-control study, the Cardiac Physiology in Malnutrition (CAPMAL) study, of 88 children with SAM (exposed) vs 22 severity-matched patients without SAM (unexposed) was conducted between March 7, 2011, and February 20, 2012; data analysis was performed from October 1, 2012, to March 1, 2016. Echocardiographic and electrocardiographic (ECG) recordings (including 7-day Holter monitoring) at admission, day 7, and day 28. Findings in children with (cases) and without (controls) SAM and in marasmus and kwashiorkor phenotypes were compared. Eighty-eight children (52 with marasmus and 36 with kwashiorkor) of the 418 admitted with SAM and 22 severity-matched controls were studied. A total of 63 children (57%) were boys; median age at admission was 19 months (range, 12-39 months). On admission, abnormalities more common in cases vs controls included severe hypokalemia (potassium <2.5 mEq/L) (18 of 81 [22%] vs 0%), hypoalbuminemia (albumin level <3.4 g/dL) (66 of 88 [75%] vs 4 of 22 [18%]), and hypothyroidism (free thyroxine level <0.70 ng/dL or thyrotropin level >4.2 mU/L) (18 of 74 [24%] vs 1 of 21 [5%]) and were associated with typical electrocardiographic changes (T-wave inversion: odds ratio, 7.3; 95% CI, 1.9-28.0; P = .001), which corrected as potassium levels improved. Fourteen children with SAM (16%) but no controls died. Myocardial mass was lower in cases on admission but not by day 7. Results of the Tei Index, a measure of global cardiac function, were within the reference range and similar in cases (median, 0.37; interquartile range [IQR], 0.26-0.45) and controls (median, 0.36; IQR, 0.28-0.42). Echocardiography detected no evidence of cardiac failure among children with SAM, including those receiving intravenous fluids to correct hypovolemia. Cardiac dysfunction was generally associated with comorbidity and typical of hypovolemia, with low cardiac index (median, 4.9 L/min/m2; IQR, 3.9-6.1 L/min/m2), high systemic vascular resistance index (median, 1333 dyne seconds/cm5/m2; IQR, 1133-1752 dyne seconds/cm5/m2), and with few differences between the marasmus and kwashiorkor manifestations of malnutrition. Seven-day continuous ECG Holter monitoring during the high-risk initial refeeding period demonstrated self-limiting significant ventricular arrhythmias in 33 of 55 cases (60%) and 6 of 18 controls (33%) (P = .049); none were temporally related to adverse events, including fatalities. There is little evidence that African children with SAM are at greater risk of cardiac dysfunction or clinically significant arrhythmias than those without SAM or that marasmus and kwashiorkor differed in cardiovascular profile. These findings should prompt a review of current guidelines.

Abstract 17313: Myocardial Remodeling in Atrial Fibrillation is Not Associated With Supraventricular or Ventricular Ectopic Activity: Results From a Cardiac Imaging Study

Background: Myocardial remodeling in atrial fibrillation (AF) is a continuum of structural, hemodynamic, and electrophysical changes that often coexist in a complex pathophysiological interplay. Purpose: The aim of this study was to evaluate whether cardiac magnetic resonance imaging (CMR) derived myocardial strain, by tracking subtle alterations in myocardial function, was associated with premature atrial (PAC) and ventricular (PVC) complexes, detected by 7-day Holter-monitoring. Methods: A total of 95 patients (mean age 63±8.5 years, 52% male) with a history of paroxysmal (51%) or persistent AF (49%) underwent CMR and 7-day Holter-monitoring during sinus rhythm. Left atrial measures, including volume, ejection fraction, peak systolic longitudinal, radial and circumferential strain were assessed using cine CMR feature tracking by commercially available software (Circle, Calgary, Canada). Holter-monitoring was used to determine heart rate and rhythm, including the presence of PACs and PVCs. The associations between strain variables and Holter-variables were examined using multivariable linear regression, adjusted for age, sex, and AF type. Results: Left atrial end-diastolic volume was significantly increased, particularly in patients with persistent AF, when compared with healthy controls (persistent AF 132±32 ml vs. healthy 77±14 ml). Similarly, left atrial ejection fraction was significantly reduced in persistent AF as compared with normal reference values (48±10 ml vs. 54±10 ml). There were no significant associations between CMR strain parameters and average PACs per hour, average PVCs per hour, average PACs per sinus beats per hour or average PVCs per sinus beats per hour. These associations remained unaltered after adjusting for age, sex, and AF type. Finally, no significant interactions with AF type were found. Conclusions: Despite significant myocardial remodeling in left atrium shown by increased end-diastolic volume and decreased left atrial ejection fraction, there was no correlation with increased ectopic activity as assessed by 7-day ambulatory Holter monitoring. Image

On the Beat Detection Performance in Long-Term ECG Monitoring Scenarios.

Despite the wide literature on R-wave detection algorithms for ECG Holter recordings, the long-term monitoring applications are bringing new requirements, and it is not clear that the existing methods can be straightforwardly used in those scenarios. Our aim in this work was twofold: First, we scrutinized the scope and limitations of existing methods for Holter monitoring when moving to long-term monitoring; Second, we proposed and benchmarked a beat detection method with adequate accuracy and usefulness in long-term scenarios. A longitudinal study was made with the most widely used waveform analysis algorithms, which allowed us to tune the free parameters of the required blocks, and a transversal study analyzed how these parameters change when moving to different databases. With all the above, the extension to long-term monitoring in a database of 7-day Holter monitoring was proposed and analyzed, by using an optimized simultaneous-multilead processing. We considered both own and public databases. In this new scenario, the noise-avoid mechanisms are more important due to the amount of noise that exists in these recordings, moreover, the computational efficiency is a key parameter in order to export the algorithm to the clinical practice. The method based on a Polling function outperformed the others in terms of accuracy and computational efficiency, yielding 99.48% sensitivity, 99.54% specificity, 99.69% positive predictive value, 99.46% accuracy, and 0.85% error for MIT-BIH arrhythmia database. We conclude that the method can be used in long-term Holter monitoring systems.

Ambulatory electrocardiographic evaluation of the occurrence of arrhythmias in healthy Salukis.

OBJECTIVE To determine the frequency and complexity of ventricular arrhythmias in a group of healthy Salukis evaluated by means of continuous Holter monitoring for 7 days. DESIGN Prospective case series. ANIMALS 25 healthy Salukis > 18 months old. PROCEDURES In all dogs, a history was obtained and a physical examination and transthoracic echocardiography were performed to verify the absence of structural cardiac disease. Dogs then underwent Holter monitoring for 7 days. Data recorded included heart rate parameters and the occurrence of conduction disturbances, ventricular premature complexes, ventricular couplets, ventricular triplets, ventricular bigeminy, ventricular trigeminy, and ventricular tachycardia. RESULTS 25 dogs (13 sexually intact females, 2 spayed females, and 10 sexually intact males) were enrolled in the study. All 25 dogs had at least one 24-hour period during which ventricular premature complexes were detected. Median number of ventricular premature complexes during any 24-hour period in all dogs was 2 (interquartile [25th to 75th percentile] range, 0 to 4). There were no significant differences between males and females in regard to median number of ventricular premature complexes per 24-hour period or recorded heart rate parameters. CONCLUSIONS AND CLINICAL RELEVANCE For Salukis in the study population, 7-day Holter monitoring revealed infrequent ventricular arrhythmias. These findings suggested that detection of a ventricular arrhythmia in a healthy Saluki may be an indication for further diagnostic evaluation.

The impact of supraventricular ectopic complexes in different age groups and risk of recurrent atrial fibrillation after antiarrhythmic medication or catheter ablation.

Supraventricular ectopic complexes (SVEC) are known risk factors of recurrent atrial fibrillation (AF). However, the impact of SVEC in different age groups is unknown. We aimed to investigate the risk of AF recurrence with higher SVEC burden in patients ±57years, respectively, after treatment with antiarrhythmic medication (AAD) or catheter ablation (CA). In total, 260 patients with LVEF >40% and age ≤70 years were randomized to AAD (N=132) or CA (N=128) as first-line treatment for paroxysmal AF. All patients underwent 7-day Holter monitoring at baseline, and after 3, 6, 12, 18 and 24months and were categorized according to median age ±57years. We used multivariate Cox regression analyses and we defined high SVEC burden at 3months of follow-up as the upper 75th percentile >195SVEC/day. AF recurrence was defined as AF ≥1min, AF-related cardioversion or hospitalization. Age >57years were significantly associated with higher AF recurrence rate after CA (58% vs 36%, p=0.02). After CA, we observed a higher SVEC burden during follow-up in patients >57years which was not observed in the younger age group treated with CA (p=0.006). High SVEC burden at 3months after CA was associated with AF recurrence in older patients but not in younger patients (>57years: HR 3.4 [1.4-7.9], p=0.005). We did not find any age-related differences after AAD. We found that younger and older patients respond differently to CA and that SVEC burden was only associated with AF recurrence in older patients.

Effectiveness and safety of simultaneous hybrid thoracoscopic endocardial catheter ablation of atrial fibrillation in obese and non-obese patients.

We evaluated the safety and effectiveness of the hybrid thoracoscopic endocardial epicardial ablation technique for the treatment of atrial fibrillation (AF) in obese versus non-obese patients. Between January 2010 and January 2015, a cohort of 61 patients were retrospectively identified to undergo ablation of AF as a stand-alone procedure using a thoracoscopic, hybrid epicardial-endocardial technique. All patients underwent continuous 7-day Holter monitoring at 3, 6 months, 1 year and yearly thereafter. A total of 40% of the obese cohort had persistent or long-standing AF, compared to 54.9% of the non-obese cohort. There were no deaths or conversion to cardiopulmonary bypass required. At 3-year follow-up, 60% of the obese group were in sinus rhythm (SR) with no episode of AF, atrial flutter or atrial tachycardia lasting 30 s off anti-arrhythmic drugs. This was compared to 70.6% in the non-obese group, with no significant difference between the groups (P=0.468). For success rates on anti-arrhythmic drugs, this was 80% in the obese group compared to 86% in the non-obese group at 3-year follow-up (P=0.637). No patient died and no thromboembolic/bleeding events or procedure-related complications occurred during the follow-up. In a retrospective cohort with approximately half with persistent or long-standing AF, thoracoscopic hybrid epicardial endocardial ablation proved to be equally effective and safe in obese versus non-obese patients. Current preliminary findings require further validation in multi-institutional prospective studies with larger sample sizes.

Middle-term results of hybrid atrial fibrillation ablation using AtriCure system

IntroductionLong-term results of catheter ablation (CA) for persistent and long-standing persistent atrial fibrillation (AF) are disappointing. The hybrid approach is currently one of options for overcoming the limitations of CA. AimTo evaluate the safety and medium-term efficacy of the hybrid approach in patients with persistent and long-standing persistent AF. MethodsAll patients underwent epicardial thoracoscopic radiofrequency (RF) pulmonary vein (PV) isolation using the AtriCure clamp followed by left atrial (LA) linear lesions (using a linear pen), Marshall ligament disruption, and LA appendage exclusion using an Atriclip. All patients underwent an electrophysiological study (EPS) and RF CA 2–3 months after the initial surgery to eliminate recurrent conductions from/to the PVs or across the linear lesions, and to eliminate all spontaneous and inducible atrial arrhythmias. 7-Day ECG Holter monitoring was performed every 3 months during the first year and every 6 months afterwards to evaluate possible recurrent arrhythmias. ResultsSeventy patients (49 male, median 63.5 years) took part in the study. EPS was performed 87 days (median) after the thoracoscopic surgery. Seventy-six percent of patients were in normal sinus rhythm (SR) at the start of the EPS, 7% had typical atrial flutter, 11% had atrial tachycardia, and 6% were in AF. After completion of the hybrid approach, all PVs were isolated, while a complete conduction block across the linear lines was achieved in 88.6% of patients. Twelve months after the procedure, 77.1% of patients had a stable SR without any anti-arrhythmic medication or re-ablation. If we included those on anti-arrhythmic drugs and re-ablation procedures, SR was achieved in 96.5% of patients during follow-up (936±432 days). ConclusionThe sequential hybrid approach is probably the most effective and relatively safe invasive treatment for persistent and long-term persistent AF with very low medium- to long-term recurrences. Introduction of the hybrid approach to clinical practice requires extensive cooperation between cardiologic and cardiothoracic teams.

Antiarrhythmic medication is superior to catheter ablation in suppressing supraventricular ectopic complexes in patients with atrial fibrillation

BackgroundSupraventricular ectopic complexes (SVEC) originating in the pulmonary veins are known triggers of atrial fibrillation (AF) which led to the development of pulmonary vein isolation for AF. However, the long-term prevalence of SVEC after catheter ablation (CA) as compared to antiarrhythmic medication (AAD) is unknown. Our aims were to compare the prevalence of SVEC after AAD and CA and to estimate the association between baseline SVEC burden and AF burden during 24months of follow-up. MethodsPatients with paroxysmal AF (N=260) enrolled in the MANTRA PAF trial were treated with AAD (N=132) or CA (N=128). At baseline and 3, 6, 12, 18 and 24months follow-up patients underwent 7-day Holter monitoring to assess SVEC and AF burden. We compared SVEC burden between treatments with Wilcoxon sum rank test. ResultsPatients treated with AAD had significantly lower daily SVEC burden during follow-up as compared to CA (AAD: 19 [6–58] versus CA: 39 [14–125], p=0.003). SVEC burden increased post-procedurally followed by a decrease after CA whereas after AAD SVEC burden decreased and stabilized after 3months of follow-up. Patients with low SVEC burden had low AF burden after both treatments albeit this was more pronounced after CA at 24months of follow-up. ConclusionAAD was superior to CA in suppressing SVEC burden after treatment of paroxysmal AF. After CA SVEC burden increased immediately post-procedural followed by a decrease whereas after AAD an early decrease was observed. Lower SVEC burden was highly associated with lower AF burden during follow-up especially after CA.

Cost-Effectiveness and Clinical Effectiveness of the Risk Factor Management Clinic in Atrial Fibrillation: The CENT Study.

Atrial fibrillation (AF) imposes a substantial cost burden on the healthcare system. Weight and risk factor management (RFM) reduces AF burden and improves the outcomes of AF ablation. This study sought to evaluate the cost and clinical effectiveness of integrating RFM into the overall management of AF. Of 1,415 consecutive patients with symptomatic AF, 825 patients had body mass index≥27 kg/m2. After screening for exclusion criteria, the final cohort comprised 355 patients: 208 patients who opted for RFM and 147 control subjects and were followed by 3 to 6 monthly clinic review, 7-day Holter monitoring, and AF Symptom Score. A decisionanalytical model calculated the incremental cost-effectiveness ratios of cost per unit of global well-being gained and unit of AF burden reduced. There were no differences in baseline characteristics or follow-up duration (p= NS). Arrhythmia-free survival was better in the RFM compared with control subjects (Kaplan-Meier: 79% vs. 44%; p< 0.001). At follow-up, RFM group had less unplanned specialist visits (0.19 ± 0.40 vs. 1.94 ± 2.00; p< 0.001), hospitalizations (0.74 ± 1.3 vs. 1.05± 1.60; p= 0.03), cardioversions (0.89 ± 1.50 vs. 1.51 ± 2.30; p= 0.002), emergency presentations (0.18 ± 0.50 vs. 0.76 ± 1.20; p< 0.001), and ablation procedures (0.60 ± 0.69 vs. 0.72 ± 0.86; p= 0.03). Antihypertensive (0.53±0.70 vs. 0.78 ± 0.60; p=0.04) and antiarrhythmic (0.26 ± 0.50 vs. 0.91 ± 0.60; p= 0.003) use declined in RFM. The RFM group had an increase of 0.1930 quality-adjusted life years and a cost saving of $12,094 (incremental cost-effectiveness ratios of $62,653 saved per quality-adjusted life years gained). A structured physician-directed RFM program is clinically effective and cost saving.

Lone Atrial Fibrillation Is Associated With Impaired Left Ventricular Energetics That Persists Despite Successful Catheter Ablation.

Lone atrial fibrillation (AF) may reflect a subclinical cardiomyopathy that persists after sinus rhythm (SR) restoration, providing a substrate for AF recurrence. To test this hypothesis, we investigated the effect of restoring SR by catheter ablation on left ventricular (LV) function and energetics in patients with AF but no significant comorbidities. Fifty-three patients with symptomatic paroxysmal or persistent AF and without significant valvular disease, uncontrolled hypertension, coronary artery disease, uncontrolled thyroid disease, systemic inflammatory disease, diabetes mellitus, or obstructive sleep apnea (ie, lone AF) undergoing ablation and 25 matched control subjects in SR were investigated. Magnetic resonance imaging quantified LV ejection fraction (LVEF), peak systolic circumferential strain (PSCS), and left atrial volumes and function, whereas phosphorus-31 magnetic resonance spectroscopy evaluated ventricular energetics (ratio of phosphocreatine to ATP). AF burden was determined before and after ablation by 7-day Holter monitoring; intermittent ECG event monitoring was also undertaken after ablation to investigate for asymptomatic AF recurrence. Before ablation, both LV function and energetics were significantly impaired in patients compared with control subjects (LVEF, 61% [interquartile range (IQR), 52%-65%] versus 71% [IQR, 69%-73%], P<0.001; PSCS, -15% [IQR, -11 to -18%] versus -18% [IQR, -17% to -19%], P=0.002; ratio of phosphocreatine to ATP, 1.81±0.35 versus 2.05±0.29, P=0.004). As expected, patients also had dilated and impaired left atria compared with control subjects (all P<0.001). Early after ablation (1-4 days), LVEF and PSCS improved in patients recovering SR from AF (LVEF, 7.0±10%, P=0.005; PSCS, -3.5±4.3%, P=0.001) but were unchanged in those in SR during both assessments (both P=NS). At 6 to 9 months after ablation, AF burden reduced significantly (from 54% [IQR, 1.5%-100%] to 0% [IQR 0%-0.1%]; P<0.001). However, LVEF and PSCS did not improve further (both P=NS) and remained impaired compared with control subjects (P<0.001 and P=0.003, respectively). Similarly, there was no significant improvement in atrial function from before ablation (P=NS), and this remained lower than in control subjects (P<0.001). The ratio of phosphocreatine to ATP was unaffected by heart rhythm during assessment and AF burden before ablation (both P=NS). It was unchanged after ablation (P=0.57), remaining lower than in control subjects regardless of both recovery of SR and freedom from recurrent AF (P=0.006 and P=0.002, respectively). Patients with lone AF have impaired myocardial energetics and subtle LV dysfunction, which do not normalize after ablation. These findings suggest that AF may be the consequence (rather than the cause) of an occult cardiomyopathy, which persists despite a significant reduction in AF burden after ablation.

Natriuretic peptides for the detection of paroxysmal atrial fibrillation

Background and purposeSilent atrial fibrillation (AF) and tachycardia (AT) are considered precursors of ischaemic stroke. Therefore, detection of paroxysmal atrial rhythm disorders is highly relevant, but is clinically challenging. We...

Impact of CARDIOrespiratory FITness on Arrhythmia Recurrence in Obese Individuals With Atrial Fibrillation: The CARDIO-FIT Study

BackgroundObesity begets atrial fibrillation (AF). Although cardiorespiratory fitness is protective against incident AF in obese individuals, its effect on AF recurrence or the benefit of cardiorespiratory fitness gain is unknown. ObjectivesThis study sought to evaluate the role of cardiorespiratory fitness and the incremental benefit of cardiorespiratory fitness improvement on rhythm control in obese individuals with AF. MethodsOf 1,415 consecutive patients with AF, 825 had a body mass index ≥27 kg/m2 and were offered risk factor management and participation in a tailored exercise program. After exclusions, 308 patients were included in the analysis. Patients underwent exercise stress testing to determine peak metabolic equivalents (METs). To determine a dose response, cardiorespiratory fitness was categorized as: low (<85%), adequate (86% to 100%), and high (>100%). Impact of cardiorespiratory fitness gain was ascertained by the objective gain in fitness at final follow-up (≥2 METs vs. <2 METs). AF rhythm control was determined using 7-day Holter monitoring and AF severity scale questionnaire. ResultsThere were no differences in baseline characteristics or follow-up duration between the groups defined by cardiorespiratory fitness. Arrhythmia-free survival with and without rhythm control strategies was greatest in patients with high cardiorespiratory fitness compared to adequate or low cardiorespiratory fitness (p < 0.001 for both). AF burden and symptom severity decreased significantly in the group with cardiorespiratory fitness gain ≥2 METs as compared to <2 METs group (p < 0.001 for all). Arrhythmia-free survival with and without rhythm control strategies was greatest in those with METs gain ≥2 compared to those with METs gain <2 in cardiorespiratory fitness (p < 0.001 for both). ConclusionsCardiorespiratory fitness predicts arrhythmia recurrence in obese individuals with symptomatic AF. Improvement in cardiorespiratory fitness augments the beneficial effects of weight loss. (Evaluating the Impact of a Weight Loss on the Burden of Atrial Fibrillation [AF] in Obese Patients; ACTRN12614001123639)

A minimal or maximal ablation strategy to achieve pulmonary vein isolation for paroxysmal atrial fibrillation: a prospective multi-centre randomized controlled trial (the Minimax study)

Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation of atrial fibrillation (AF). The intervenous ridge (IVR) may be incorporated into ablation strategies to achieve PVI; however, randomized trials are lacking. We performed a randomized multi-centre international study to compare the outcomes of (i) circumferential antral PVI (CPVI) alone (minimal) vs. (ii) CPVI with IVR ablation to achieve individual PVI (maximal). Two hundred and thirty-four patients with paroxysmal AF underwent CPVI and were randomized to a minimal or maximal ablation strategy. The primary outcome of recurrent atrial arrhythmia was assessed with 7-day Holter monitoring at 6 and 12 months. PVI was achieved in all patients. Radiofrequency ablation time was longer in the maximal group (46.6 ± 14.6 vs. 41.5 ± 13.1 min; P < 0.01), with no significant differences in procedural or fluoroscopy times. At mean follow-up of 17 ± 8 months, there was no difference in freedom from AF after a single procedure between a minimal (70%) and maximal ablation strategy (62%; P = 0.25). In the minimal group, ablation was required on the IVR to achieve electrical isolation in 44%, and was associated with a significant reduction in freedom from AF (57%) compared with the minimal group without IVR ablation (80%; P < 0.01). There was no statistically significant difference in freedom from AF between a minimal and maximal ablation strategy. Despite attempts to achieve PVI with antral ablation, IVR ablation is commonly required. Patients in whom antral isolation can be achieved without IVR ablation have higher long-term freedom from AF (the Minimax study; ACTRN12610000863033).