In persistent atrial fibrillation (AF), localized extra-pulmonary vein sources may contribute to arrhythmia recurrences after pulmonary vein isolation. This in-silico study proposes a high-density ...sequential mapping strategy to localize such sources.
Catheter repositioning was guided by repetitive conduction patterns, moving against the prevailing conduction direction (upstream) toward the sources. Sources were found either by locally identifying conduction patterns or by encircling the region harboring them. We simulated source tracking in an in-silico atrial model, comparing random vs. upstream-guided catheter repositioning (with and without encircling). To assess performance in increasing AF complexities, we simulated AF in 3 groups: atria with reentry-anchoring scars, without fibrosis, and with severe endomysial fibrosis.
Compared to random mapping, the upstream-guided approach successfully located sources more often (anchored reentries: 70.6% vs. 10.6%; no fibrosis: 87.9% vs. 22.1%; with fibrosis: 95.0% vs. 60.9% of tracking procedures, all p<0.001), using fewer steps (median IQR: 11 7;23 vs. 26 13;35; 10 6;19 vs. 19 10;27; 11 7;19 vs. 16 8;30, respectively, all p<0.05). Adding source encircling increased source detection (98.1 %, 100 %, and 99.5 %, all p<0.01 vs. local detection only), reducing required steps (9 6;12, 8 6;12, and 9 6;13, all p<0.05). In some cases (11.9 %, 17.1 %, and 10.5 % of procedures), the algorithm encircled regions >15 mm from the source.
Moving mapping catheters upstream improves source detection efficiency, even in the presence of severe fibrosis. Encircling sources may help find regions of interest in fewer steps.
•Extra-pulmonary vein sources may lead to atrial fibrillation recurrences.•We propose a mapping strategy to find sources from repetitive activation patterns.•Guiding catheters upstream of the conduction direction leads efficiently to sources.•Encircling sources may improve their detection, but slightly reduces accuracy.•The mapping approach was robust to high fibrosis-related AF complexity.
Aims
The European CRT Survey is a joint initiative of the Heart Failure Association (HFA) and the European Heart Rhythm Association (EHRA) of the European Society of Cardiology evaluating the ...contemporary implantation practice of cardiac resynchronization therapy (CRT) in Europe.
Methods and results
Patients who had a successful CRT implantation were enrolled from 141 centres in 13 countries between November 2008 and June 2009. Baseline demographics, clinical and implantation data were collected, with a follow-up of ∼1 year (9-15 months). The current report describes clinical outcomes including symptom severity, cardiovascular (CV) hospitalization, and survival. A total of 2438 patients were enrolled, and follow-up data were acquired from 2111 patients (87%). The population included important groups of patients poorly represented in randomized controlled trials, including very elderly patients and those with prior device implantation, atrial fibrillation, and/or QRS duration <120 ms. Investigators reported substantial improvement in New York Heart Association (NYHA) functional class at follow-up. Patient self-assessment indicated that 81% of the patients felt improved, 16% reported no change, and 4% reported deterioration. During follow-up, 207 (10%) patients died, 346 (16%) had a CV hospitalization, and 501 (24%) died or had CV hospitalization. Worse NYHA functional class, atrial fibrillation, ischaemic aetiology, and device type (CRT-P, i.e. CRT alone) were associated with poorer survival. Women had a better outcome, as did patients who had a CRT-D (with an implantable cardioverter defibrillator function) device.
Conclusions
Outcomes including death and hospitalization in this European CRT survey were consistent with results from clinical trials of CRT. At 1 year follow-up, most patients who received a CRT device considered their symptoms improved compared with their pre-implant assessment. Although prospective, this is an observational study of successful CRT implantations, and outcomes in subgroup analyses must be interpreted with appropriate conservatism.
Clinical study no: NCT 01185392
Background Once the return of spontaneous circulation after out-of-hospital cardiac arrest is achieved, a 12-lead ECG is strongly recommended to identify candidates for urgent coronary angiography. ...ECG has no apparent role in mortality risk stratification. We aimed to assess whether ECG features could be associated with 30-day survival in patients with out-of-hospital cardiac arrest. Methods and Results All the post-return of spontaneous circulation ECGs from January 2015 to December 2018 in 3 European centers (Pavia, Lugano, and Vienna) were collected. Prehospital data were collected according to the Utstein style. A total of 370 ECGs were collected: 287 men (77.6%) with a median age of 62 years (interquartile range, 53-70 years). After correction for the return of spontaneous circulation-to-ECG time, age >62 years (hazard ratio HR, 1.78 95% CI, 1.21-2.61;
=0.003), female sex (HR, 1.5 95% CI, 1.05-2.13;
=0.025), QRS wider than 120 ms (HR, 1.64 95% CI, 1.43-1.87;
<0.001), the presence of a Brugada pattern (HR, 1.49 95% CI, 1.39-1.59;
<0.001), and the presence of ST-segment elevation in >1 segment (HR, 1.75 95% CI, 1.59-1.93;
<0.001) were independently associated with 30-day mortality. A score ranging from 0 to 26 was created, and by dividing the population into 3 tertiles, 3 classes of risk were found with significantly different survival rate at 30 days (score 0-4, 73%; score 5-7, 66%; score 8-26, 45%). Conclusions The post-return of spontaneous circulation ECG can identify patients who are at high risk of mortality after out-of-hospital cardiac arrest earlier than other forms of prognostication. This provides important risk stratification possibilities in postcardiac arrest care that could help to direct treatments and improve outcomes in patients with out-of-hospital cardiac arrest.
In all patients, the reason for inappropriateness was the more pronounced T-wave during type 1 BrS-ECG (Figure 1). ...the primary, secondary, and alternate vectors were generally less often ...appropriate during the development of a type 1 BrS-ECG, with the primary sensing vector being appropriate in 18 of 21 patients at baseline and in 15 of 21 patients during type 1 BrS-ECG. ...critical analysis is necessary to ensure appropriate sensing and to prevent inappropriate sensing in BrS patients with an S-ICD.
Objectives The purpose of this study is to determine whether, in patients with atrial fibrillation (AF) undergoing cardiac resynchronization therapy (CRT), atrioventricular junction ablation (AVJA) ...is associated with a better outcome than treatment with rate-slowing drugs. Background Different trials have demonstrated that CRT is effective in treating heart failure (HF) patients who are in sinus rhythm (SR). No trials have addressed whether CRT confers similar benefits on AF patients, with or without AVJA. Methods The clinical outcomes of CRT for patients with permanent AF undergoing CRT combined with either AVJA (n = 443) or rate-slowing drugs (n = 895) were compared with those of SR patients (n = 6,046). Results Median follow-up was 37 months. Total mortality (6.8 vs. 6.1 per 100 person-years) and cardiac mortality (4.2 vs. 4.0) were similar for patients with AF+AVJA and patients in SR (both p = NS). In contrast, the AF+drugs group had a higher total and cardiac mortality than the SR group and the AF+AVJA group (11.3 and 8.1, respectively; p < 0.001). On multivariable analysis, AF+AVJA had total mortality (hazard ratio HR: 0.93, 95% confidence interval CI: 0.74 to 1.67) and cardiac mortality (HR: 0.88, 95% CI: 0.66 to 1.17) similar to that of the SR group, independent of known confounders. The AF+drugs group, however, had a higher total mortality (HR: 1.52, 95% CI: 1.26 to 1.82) and cardiac mortality (HR: 1.57, 95% CI: 1.27 to 1.94) than both the SR group and the AF+AVJA group (both p < 0.001). Conclusions Long-term survival after CRT among patients with AF+AVJA is similar to that observed among patients in SR. Mortality is higher for AF patients treated with rate-slowing drugs.
Unrecognized incomplete pulmonary vein isolation (PVI), as opposed to post-PVI pulmonary vein reconnection, may be responsible for clinical recurrences of atrial fibrillation (AF). To date, no data ...are available on the use of high-resolution mapping (HRM) during cryoballoon (CB) ablation for AF as the index procedure. The aims of this study were: - to assess the value of using a HRM system during CB ablation procedures in terms of ability in acutely detecting incomplete CB lesions; - to compare the 8-pole circular mapping catheter (CMC, Achieve) and the 64-pole mini-basket catheter (Orion) with respect to pulmonary vein (PV) signals detection at baseline and after CB ablation; - to characterize the extension of the lesion produced by CB ablation by means of high-density voltage mapping.
Consecutive patients with drug-resistant paroxysmal or early-persistent AF undergoing CB ablation as the index procedure, assisted by a HRM system, were retrospectively included in this study.
A total of 33 patients (25 males; mean age: 59 ± 18 years, 28 paroxysmal AF) were included. At baseline, CMC catheter revealed PV activity in 102 PVs (77%), while the Orion documented PV signals in all veins (100%). Failure of complete CB-PVI was more frequently revealed by atrial re-mapping with the Orion as compared to the Achieve catheter (24% vs 0%, p < 0.05). A repeat ablation was performed in 8 patients (24%). In 9% of cases, the Orion catheter detected far-field signals originating from the right atrium. Quantitative assessment of the created lesion revealed a significant reduction of the left atrial area having voltage >0.5 mV. A total of 29 patients (88%) remained free of symptomatic AF during a mean follow-up of 13.2 ± 3.7 months.
Atrial re-mapping after CB ablation by means of a HRM system improves the detection of areas of incomplete ablation, characterizes the extension of the cryo-ablated tissue and can identify abolishment of potential non-PVI related sources of AF.
•Unrecognized incomplete PVI may be responsible for clinical recurrences of AF.•Identification of incomplete acute efficacy of PVI is clinically relevant.•Atrial high-resolution mapping enables accurate detection of incomplete CB-PVI.•Atrial high-resolution mapping characterizes the extension of cryoablation.•High-resolution mapping identifies abolishment by CB of non-PVI related sources of AF.
Background Short ECG P-wave duration has recently been demonstrated to be associated with higher risk of atrial fibrillation (AF). The aim of this study was to assess the rate of AF recurrence after ...pulmonary vein isolation in patients with a short P wave, and to mechanistically elucidate the observation by computer modeling. Methods and Results A total of 282 consecutive patients undergoing a first single-pulmonary vein isolation procedure for paroxysmal or persistent AF were included. Computational models studied the effect of adenosine and sodium conductance on action potential duration and P-wave duration (PWD). About 16% of the patients had a PWD of 110 ms or shorter (median PWD 126 ms, interquartile range, 115 ms-138 ms; range, 71 ms-180 ms). At Cox regression, PWD was significantly associated with AF recurrence (
=0.012). Patients with a PWD <110 ms (hazard ratio HR, 2.20; 95% CI, 1.24-3.88;
=0.007) and patients with a PWD ≥140 (HR, 1.87, 95% CI, 1.06-3.30;
=0.031) had a nearly 2-fold increase in risk with respect to the other group. In the computational model, adenosine yielded a significant reduction of action potential duration 90 (52%) and PWD (7%). An increased sodium conductance (up to 200%) was robustly accompanied by an increase in conduction velocity (26%), a reduction in action potential duration 90 (28%), and PWD (22%). Conclusions One out of 5 patients referred for pulmonary vein isolation has a short PWD which was associated with a higher rate of AF after the index procedure. Computer simulations suggest that shortening of atrial action potential duration leading to a faster atrial conduction may be the cause of this clinical observation.
The standard 12-lead ECG has been shown to be of value in characterizing atrial conduction properties. The added value of extended ECG recordings (longer recordings from more sites) has not been ...systematically explored yet.
The aim of this study is to employ an extended ECG to identify characteristics of atrial electrical activity related to paroxysmal vs. persistent atrial fibrillation (AF).
In 247 participants scheduled for AF ablation, an extended ECG was recorded (12 standard plus 3 additional leads, 5 min recording, no filtering). For patients presenting in sinus rhythm (SR), the signal-averaged P-wave and the spatiotemporal P-wave variability was analyzed. For patients presenting in AF, f-wave properties in the QRST (the amplitude complex of the ventricular electrical activity: Q-, R-, S-, and T-wave)-canceled ECG were determined.
Significant differences between paroxysmal (
= 152) and persistent patients with AF (
= 95) were found in several P-wave and f-wave parameters, including parameters that can only be calculated from an extended ECG. Furthermore, a moderate, but significant correlation was found between echocardiographic parameters and P-wave and f-wave parameters. There was a moderate correlation of left atrial (LA) diameter with P-wave energy duration (
= 0.317,
< 0.001) and f-wave amplitude in lead A3 (
= -0.389,
= 0.002). The AF-type classification performance significantly improved when parameters calculated from the extended ECG were taken into account area under the curve (AUC) = 0.58, interquartile range (IQR) 0.50-0.64 for standard ECG parameters only vs. AUC = 0.76, IQR 0.70-0.80 for extended ECG parameters,
< 0.001.
The P- and f-wave analysis of extended ECG configurations identified specific ECG features allowing improved classification of paroxysmal vs. persistent AF. The extended ECG significantly improved AF-type classification in our analyzed data as compared to a standard 10-s 12-lead ECG. Whether this can result in a better clinical AF type classification warrants further prospective study.
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