Diagnostic yield of implantable loop recorders: Results from the Hellenic registry.

AIMS: Implantable loop recorders (ILRs) are increasingly being used for long-term cardiac monitoring in different clinical settings. The aim of this study was to investigate the real-world performance of ILRs-including the time to diagnosis- in unselected patients with different ILR indications. METHODS AND RESULTS: In this multicenter, observational study, 871 patients with an indication of pre-syncope/syncope (61.9%), unexplained palpitations (10.4%), and atrial fibrillation (AF) detection with a history of cryptogenic stroke (CS) (27.7%) underwent ILR implantation. The median follow-up was 28.8 ± 12.9 months. In the presyncope/syncope group, 167 (31%) received a diagnosis established by the device. Kaplan-Meier estimates indicated that 16.9% of patients had a diagnosis at 6 months, and the proportion increased to 22.5% at 1 year. Of 91 patients with palpitations, 20 (22%) received a diagnosis based on the device. The diagnosis established at 12.2% of patients at 6 months, and the proportion increased to 13.3% at 1 year. Among 241 patients with CS, 47 (19.5%) were diagnosed with AF. The diagnostic yield of the device was 10.4% at 6 months and 12.4% at 1 year. In all cases, oral anticoagulation was initiated. Overall, ILR diagnosis altered the therapeutic strategy in 26.1% in presyncope/syncope group, 2.2% in palpitations group, and 3.7% in CS group in addition to oral anticoagulation initiation. CONCLUSIONS: In this real-world patient population, ILR determines diagnosis and initiates a new therapeutic management in nearly one fourth of patients. ILR implantation is valuable in the evaluation of patients with unexplained presyncope/syncope, CS and palpitations.

Performance of Different Risk Scores for the Detection of Atrial Fibrillation Among Patients With Cryptogenic Stroke.

BACKGROUND: Atrial fibrillation (AF) is a frequent underlying cause of cryptogenic stroke (CS) and its detection can be increased using implantable cardiac monitoring (ICM). We sought to evaluate different risk scores and assess their diagnostic ability in identifying patients with CS with underlying AF on ICM. METHODS: Patients with CS, being admitted to a single tertiary stroke center between 2017 and 2022 and receiving ICM, were prospectively evaluated. The CHA2DS2-VASc, HAVOC, Brown ESUS-AF, and C2HEST scores were calculated at baseline. The primary outcome of interest was the detection of AF, which was defined as at least 1 AF episode on ICM lasting for 2 consecutive minutes or more. The diagnostic accuracy measures and the net reclassification improvement were calculated for the 4 risk scores. Stroke recurrence was evaluated as a secondary outcome. RESULTS: A total of 250 patients with CS were included, and AF was detected by ICM in 20.4% (n=51) during a median monitoring period of 16 months. Patients with CS with AF detection were older compared with the rest (P=0.045). The median HAVOC, Brown ESUS-AF, and C2HEST scores were higher among the patients with AF compared with the patients without AF (all P<0.05), while the median CHA2DS2-VASc score was similar between the 2 groups. The corresponding C statistics for CHA2DS2-VASc, HAVOC, Brown ESUS-AF, and C2HEST for AF prediction were 0.576 (95% CI, 0.482-0.670), 0.612 (95% CI, 0.523-0.700), 0.666 (95% CI, 0.587-0.746), and 0.770 (95% CI, 0.699-0.839). The C2HEST score presented the highest diagnostic performance based on C statistics (P<0.05 after correction for multiple comparisons) and provided significant improvement in net reclassification for AF detection (>70%) compared with the other risk scores. Finally, stroke recurrence was documented in 5.6% of the study population, with no difference regarding the 4 risk scores between patients with and without recurrent stroke. CONCLUSIONS: The C2HEST score was superior to the CHA2DS2-VASc, HAVOC, and Brown ESUS-AF scores for discriminating patients with CS with underlying AF using ICM.

Management of Patients With Unexplained Syncope: Derivation and Validation of a Simplified 2-Step Diagnostic Approach.

BACKGROUND: The aim of this study was to develop a structured 2-step approach, based on noninvasive diagnostic criteria, that led to an electrophysiology study in patients with unexplained syncope. METHODS AND RESULTS: Two independent cohorts were used: the derivation cohort with 665 patients based on electronic health record data to develop our 2-step diagnostic approach, and the validation cohort based on 160 prospectively screened patients, presenting with unexplained syncope episodes. Noninvasive electrocardiographic and imaging markers and an electrophysiology study-based invasive assessment were combined. A positive diagnostic approach according to our study's prespecified criteria resulted in a decision to proceed with a permanent pacemaker/implantable cardioverter-defibrillator. The primary end point was the time until the event of recurrent syncope (syncope-free survival). Number needed to treat was calculated for patients with a positive diagnostic approach. The number of patients with unexplained syncope and borderline sinus bradycardia needed to treat was 5, and the number of patients with unexplained syncope and bundle branch block needed to treat was 3 over a mean follow-up of ≈4 years. After the structured 2-step approach, the primary outcome occurred in 14 of 82 (17.1%) with a pacemaker/implantable cardioverter-defibrillator and 19 of 57 (33%) with a negative approach, with a mean follow-up of ≈2.5 years (29.29±12.58 months, P=0.03). CONCLUSIONS: The low number needed to treat in the derivation cohort and the low percentage of syncope recurrence in the validation cohort supports the proposed 2-step electrophysiology-inclusive algorithm as a potentially low-cost, 1-day, structured tool for these patients.

Leadless Pacemakers: Current Achievements and Future Perspectives.

Despite the technological advances in pacemaker technology, the transvenous implanted leads are still considered the Achilles' heel of this rhythm-control therapy. The leadless permanent pacemaker system was developed as an option to bypass the weakness of the transvenous approach. Advances in battery technology and deep miniaturisation of electronics now offer the opportunity to implant the whole pacemaker system into the right ventricle. This review aims to provide a comprehensive report on the advent of leadless pacemakers, their clinical usefulness and the future perspectives of this disruptive and promising technology. Further research is required before some of these technologies are safely and routinely used in clinical practice.

The Role of ECG Strain Pattern in Prognosis after TAVI: A Sub-Analysis of the DIRECT Trial.

BACKGROUND: The presence of an electrocardiographic (ECG) strain pattern-among other ECG features-has been shown to be predictive of adverse cardiovascular outcomes in asymptomatic patients with aortic stenosis. However, data evaluating its impact on symptomatic patients undergoing TAVI are scarce. Therefore, we tried to investigate the prognostic impact of baseline ECG strain pattern on clinical outcomes after TAVI. METHODS: A sub-group of patients of the randomized DIRECT (Pre-dilatation in Transcatheter Aortic Valve Implantation Trial) trial with severe aortic stenosis who underwent TAVI with a self-expanding valve in one single center were consecutively enrolled. Patients were categorized into two groups according to the presence of ECG strain. Left ventricular strain was defined as the presence of ≥1 mm convex ST-segment depression with asymmetrical T-wave inversion in leads V5 to V6 on the baseline 12-lead ECG. Patients were excluded if they had paced rhythm or left bundle branch block at baseline. Multivariate Cox proportional hazard regression models were generated to assess the impact on outcomes. The primary clinical endpoint was all-cause mortality at 1 year after TAVI. RESULTS: Of the 119 patients screened, 5 patients were excluded due to left bundle branch block. Among the 114 included patients (mean age: 80.8 ± 7), 37 patients (32.5%) had strain pattern on pre-TAVI ECG, while 77 patients (67.5%) did not exhibit an ECG strain pattern. No differences in baseline characteristics were found between the two groups. At 1 year, seven patients reached the primary clinical endpoint, with patients in the strain group demonstrating significantly higher mortality in Kaplan-Meier plots compared to patients without left ventricular strain (five vs. two, log-rank p = 0.022). There was no difference between the strain and no strain group regarding the performance of pre-dilatation (21 vs. 33, chi-square p = 0.164). In the multivariate analysis, left ventricular strain was found to be an independent predictor of all-cause mortality after TAVI [Exp(B): 12.2, 95% Confidence Intervals (CI): 1.4-101.9]. CONCLUSION: Left ventricular ECG strain is an independent predictor of all-cause mortality after TAVI. Thus, baseline ECG characteristics may aid in risk-stratifying patients scheduled for TAVI.

Electro-Mechanical Alterations in Atrial Fibrillation: Structural, Electrical, and Functional Correlates.

Atrial fibrillation is the most common arrhythmia encountered in clinical practice affecting both patients' survival and well-being. Apart from aging, many cardiovascular risk factors may cause structural remodeling of the atrial myocardium leading to atrial fibrillation development. Structural remodelling refers to the development of atrial fibrosis, as well as to alterations in atrial size and cellular ultrastructure. The latter includes myolysis, the development of glycogen accumulation, altered Connexin expression, subcellular changes, and sinus rhythm alterations. The structural remodeling of the atrial myocardium is commonly associated with the presence of interatrial block. On the other hand, prolongation of the interatrial conduction time is encountered when atrial pressure is acutely increased. Electrical correlates of conduction disturbances include alterations in P wave parameters, such as partial or advanced interatrial block, alterations in P wave axis, voltage, area, morphology, or abnormal electrophysiological characteristics, such as alterations in bipolar or unipolar voltage mapping, electrogram fractionation, endo-epicardial asynchrony of the atrial wall, or slower cardiac conduction velocity. Functional correlates of conduction disturbances may incorporate alterations in left atrial diameter, volume, or strain. Echocardiography or cardiac magnetic resonance imaging (MRI) is commonly used to assess these parameters. Finally, the echocardiography-derived total atrial conduction time (PA-TDI duration) may reflect both atrial electrical and structural alterations.

Prolonged cardiac monitoring for stroke prevention: A systematic review and meta-analysis of randomized-controlled clinical trials.

Introduction: Prolonged cardiac monitoring (PCM) substantially improves the detection of subclinical atrial fibrillation (AF) among patients with history of ischemic stroke (IS), leading to prompt initiation of anticoagulants. However, whether PCM may lead to IS prevention remains equivocal. Patients and methods: In this systematic review and meta-analysis, randomized-controlled clinical trials (RCTs) reporting IS rates among patients with known cardiovascular risk factors, including but not limited to history of IS, who received PCM for more than 7 days versus more conservative cardiac rhythm monitoring methods were pooled. Results: Seven RCTs were included comprising a total of 9048 patients with at least one known cardiovascular risk factor that underwent cardiac rhythm monitoring. PCM was associated with reduction of IS occurrence compared to conventional monitoring (Risk Ratio: 0.76; 95% CI: 0.59-0.96; I 2 = 0%). This association was also significant in the subgroup of RCTs investigating implantable cardiac monitoring (Risk Ratio: 0.75; 95% CI: 0.58-0.97; I 2 = 0%). However, when RCTs assessing PCM in both primary and secondary prevention settings were excluded or when RCTs investigating PCM with a duration of 7 days or less were included, the association between PCM and reduction of IS did not retain its statistical significance. Regarding the secondary outcomes, PCM was related to higher likelihood for AF detection and anticoagulant initiation. No association was documented between PCM and IS/transient ischemic attack occurrence, all-cause mortality, intracranial hemorrhage, or major bleeding. Conclusion: PCM may represent an effective stroke prevention strategy in selected patients. Additional RCTs are warranted to validate the robustness of the reported associations.

Noninvasive electrocardiographic risk factors for sudden cardiac death in dilated ca rdiomyopathy: is ambulatory electrocardiography still relevant?

Risk stratification for sudden cardiac death in dilated cardiomyopathy is a field of constant debate, and the currently proposed criteria have been widely questioned due to their low positive and negative predictive value. In this study, we conducted a systematic review of the literature utilizing the PubMed and Cochrane library platforms, in order to gain insight about dilated cardiomyopathy and its arrhythmic risk stratification utilizing noninvasive risk markers derived mainly from 24 h electrocardiographic monitoring. The obtained articles were reviewed in order to register the various electrocardiographic noninvasive risk factors used, their prevalence, and their prognostic significance in dilated cardiomyopathy. Premature ventricular complexes, nonsustained ventricular tachycardia, late potentials on Signal averaged electrocardiography, T wave alternans, heart rate variability and deceleration capacity of the heart rate, all have both some positive and negative predictive value to identify patients in higher likelihood for ventricular arrhythmias and sudden cardiac death. Corrected QT, QT dispersion, and turbulence slope-turbulence onset of heart rate have yet to establish a predictive correlation in the literature. Although ambulatory electrocardiographic monitoring is frequently used in clinical practice in DCM patients, no single risk marker can be used for the selection of patients at high-risk for malignant ventricular arrhythmic events and sudden cardiac death who could benefit from the implantation of a defibrillator. More studies are needed in order to establish a risk score or a combination of risk factors with the purpose of selecting high-risk patients for ICD implantation in the context of primary prevention.

Association of non-invasive electrocardiographic risk factors with left ventricular systolic function in post-myocardial infarction patients with mildly reduced or preserved ejection fraction: Insights from the PRESERVE-EF study.

BACKGROUND: Electrocardiographic non-invasive risk factors (NIRFs) have an important role in the arrhythmic risk stratification of post-myocardial infarction (post-MI) patients with preserved or mildly reduced left ventricular ejection fraction (LVEF). However, their specific relation to left ventricular systolic function remains unclear. We aimed to evaluate the association between NIRFs and LVEF in the patients included in the PRESERVE-EF trial. METHODS: We studied 575 post-MI ischemia-free patients with LVEF≥40% (mean age: 57.0 ± 10.4 years, 86.2% men). The following NIRFs were evaluated: premature ventricular complexes, non-sustained ventricular tachycardia (NSVT), late potentials (LPs), prolonged QTc, increased T-wave alternans, reduced heart rate variability, and abnormal deceleration capacity with abnormal turbulence. RESULTS: There was a statistically significant relationship between LPs (Chi-squared = 4.975; p < .05), nsVT (Chi-squared = 5.749, p < .05), PVCs (r= -.136; p < .01), and the LVEF. The multivariate linear regression analysis showed that LPs (p = .001) and NSVT (p < .001) were significant predictors of the LVEF. The results of the multivariate logistic regression analysis indicated that LPs (OR: 1.76; 95% CI: 1.02-3.05; p = .004) and NSVT (OR: 2.44; 95% CI: 1.18-5.04; p = .001) were independent predictors of the mildly reduced LVEF: 40%-49% versus the preserved LVEF: ≥50%. CONCLUSION: Late potentials and NSVT are independently related to reduced LVEF while they are independent predictors of mildly reduced LVEF versus the preserved LVEF. These findings may have important implications for the arrhythmic risk stratification of post-MI patients with mildly reduced or preserved LVEF.

Digital health in older adults for the prevention and management of cardiovascular diseases and frailty. A clinical consensus statement from the ESC Council for Cardiology Practice/Taskforce on Geriatric Cardiology, the ESC Digital Health Committee and the ESC Working Group on e-Cardiology.

Digital health technology is receiving increasing attention in cardiology. The rise of accessibility of digital health tools including wearable technologies and smart phone applications used in medical practice has created a new era in healthcare. The coronavirus pandemic has provided a new impetus for changes in delivering medical assistance across the world. This Consensus document discusses the potential implementation of digital health technology in older adults, suggesting a practical approach to general cardiologists working in an ambulatory outpatient clinic, highlighting the potential benefit and challenges of digital health in older patients with, or at risk of, cardiovascular disease. Advancing age may lead to a progressive loss of independence, to frailty, and to increasing degrees of disability. In geriatric cardiology, digital health technology may serve as an additional tool both in cardiovascular prevention and treatment that may help by (i) supporting self-caring patients with cardiovascular disease to maintain their independence and improve the management of their cardiovascular disease and (ii) improving the prevention, detection, and management of frailty and supporting collaboration with caregivers. Digital health technology has the potential to be useful for every field of cardiology, but notably in an office-based setting with frequent contact with ambulatory older adults who may be pre-frail or frail but who are still able to live at home. Cardiologists and other healthcare professionals should increase their digital health skills and learn how best to apply and integrate new technologies into daily practice and how to engage older people and their caregivers in a tailored programme of care.

Arrhythmic risk stratification in ischemic, non-ischemic and hypertrophic cardiomyopathy: A two-step multifactorial, electrophysiology study inclusive approach.

Annual arrhythmic sudden cardiac death ranges from 0.6% to 4% in ischemic cardiomyopathy (ICM), 1% to 2% in non-ischemic cardiomyopathy (NICM), and 1% in hypertrophic cardiomyopathy (HCM). Towards a more effective arrhythmic risk stratification (ARS) we hereby present a two-step ARS with the usage of seven non-invasive risk factors: Late potentials presence (≥ 2/3 positive criteria), premature ventricular contractions (≥ 30/h), non-sustained ventricular tachycardia (≥ 1episode/24 h), abnormal heart rate turbulence (onset ≥ 0% and slope ≤ 2.5 ms) and reduced deceleration capacity (≤ 4.5 ms), abnormal T wave alternans (≥ 65µV), decreased heart rate variability (SDNN < 70ms), and prolonged QTc interval (> 440 ms in males and > 450 ms in females) which reflect the arrhythmogenic mechanisms for the selection of the intermediate arrhythmic risk patients in the first step. In the second step, these intermediate-risk patients undergo a programmed ventricular stimulation (PVS) for the detection of inducible, truly high-risk ICM and NICM patients, who will benefit from an implantable cardioverter defibrillator. For HCM patients, we also suggest the incorporation of the PVS either for the low HCM Risk-score patients or for the patients with one traditional risk factor in order to improve the inadequate sensitivity of the former and the low specificity of the latter.

Prolonged Cardiac Monitoring and Stroke Recurrence: A Meta-analysis.

BACKGROUND AND OBJECTIVES: Prolonged poststroke cardiac rhythm monitoring (PCM) reveals a substantial proportion of patients with ischemic stroke (IS) with atrial fibrillation (AF) not detected by conventional rhythm monitoring strategies. We evaluated the association between PCM and the institution of stroke preventive strategies and stroke recurrence. METHODS: We searched MEDLINE and SCOPUS databases to identify studies reporting stroke recurrence rates in patients with history of recent IS or TIA receiving PCM compared with patients receiving conventional cardiac rhythm monitoring. Pairwise meta-analyses were performed under the random effects model. To explore for differences between the monitoring strategies, we combined direct and indirect evidence for any given pair of monitoring devices assessed within a randomized controlled trial (RCT). RESULTS: We included 8 studies (5 RCTs, 3 observational; 2,994 patients). Patients receiving PCM after their index event had a higher rate of AF detection and anticoagulant initiation in RCTs (risk ratio [RR] 3.91, 95% CI 2.54-6.03; RR 2.16, 95% CI 1.66-2.80, respectively) and observational studies (RR 2.06, 95% CI 1.57-2.70; RR 2.01, 95% CI 1.43-2.83, respectively). PCM was associated with a lower risk of recurrent stroke during follow-up in observational studies (RR 0.29, 95% CI 0.15-0.59), but not in RCTs (RR 0.72, 95% CI 0.49-1.07). In indirect analyses of RCTs, the likelihood of AF detection and anticoagulation initiation was higher for implantable loop recorders compared with Holter monitors and external loop recorders. DISCUSSION: PCM after an IS or TIA can lead to higher rates of AF detection and anticoagulant initiation. There is no solid RCT evidence supporting that PCM may be associated with lower stroke recurrence risk.

Critical appraisal of technologies to assess electrical activity during atrial fibrillation: a position paper from the European heart rhythm association and European society of cardiology working group on ecardiology in collaboration with the heart rhythm society, Asia pacific heart rhythm society, Latin American Heart rhythm society and computing in cardiology

Abstract We aim to provide a critical appraisal of basic concepts underlying signal recording and processing technologies applied for (I) atrial fibrillation (AF) mapping to unravel AF mechanisms and/or identifying target sites for AF therapy and (ii) AF detection, to optimize usage of technologies, stimulate research aimed at closing knowledge gaps, and developing ideal AF recording and processing technologies. Recording and processing techniques for assessment of electrical activity during AF essential for diagnosis and guiding ablative therapy including body surface electrocardiograms (ECG) and endo- or epicardial electrograms (EGM) are evaluated. Discussion of (I) differences in uni-, bi-, and multi-polar (omnipolar/Laplacian) recording modes, (ii) impact of recording technologies on EGM morphology, (iii) global or local mapping using various types of EGM involving signal processing techniques including isochronal-, voltage- fractionation-, dipole density-, and rotor mapping, enabling derivation of parameters like atrial rate, entropy, conduction velocity/direction, (iv) value of epicardial and optical mapping, (v) AF detection by cardiac implantable electronic devices containing various detection algorithms applicable to stored EGMs, (vi) contribution of machine learning (ML) to further improvement of signals processing technologies. Recording and processing of EGM (or ECG) are the cornerstones of (body surface) mapping of AF. Currently available AF recording and processing technologies are mainly restricted to specific applications or have technological limitations. Improvements in AF mapping by obtaining highest fidelity source signals (e. g. catheter­electrode combinations) for signal processing (e. g. filtering, digitization, and noise elimination) is of utmost importance. Novel acquisition instruments (multi-polar catheters combined with improved physical modelling and ML techniques) will enable enhanced and automated interpretation of EGM recordings in the near future.

Permanent pacemaker implantation in unexplained syncope patients with electrophysiology study-proven atrioventricular node disease.

OBJECTIVE: Syncope, whose cause is unknown after an initial assessment, has an uncertain prognosis. It is critical to identify patients at the highest risk who may require a pacemaker and to identify the cause of recurrent syncope to prescribe proper therapy. The aim of this study was to evaluate the effect of permanent pacing on the incidence of syncope in patients with unexplained syncope and electrophysiology study (EPS)-proven atrioventricular (AV) node disease. METHODS: This was an observational study based on a prospective registry of 236 consecutive patients (60.20 ± 18.66 years, 63.1% male, 60.04 ± 9.50 bpm) presenting with recurrent unexplained syncope attacks admitted to our hospital for invasive EPS. The decision to implant a permanent pacemaker was made in all cases by the attending physicians according to the results of the EPS. A total of 135 patients received the antibradycardia pacemaker (ABP), while 101 patients were declined. RESULTS: The mean of reported syncope episodes was 1.97 ± 1.10 (or presyncope 2.17 ± 1.50) before they were referred for a combined EP-guided diagnostic and therapeutic approach. Over a mean follow-up of approximately 4 years (49.19 ± 29.58 months), the primary outcome event (syncope) occurred in 31 of 236 patients (13.1%), and 6 of 135 (4.4%) patients in the ABP group as compared to 25 of 101 (24.8%) in the no pacemaker group (p < 0.001). CONCLUSION: Among patients with a history of unexplained syncope, a set of positivity criteria for the presence of EPS-defined AV node disease identifies a subset of patients who will benefit from permanent pacing.

Multipoint left ventricular pacing effects on hemodynamic parameters and functional status: HUMVEE single-arm clinical trial (NCT03189368).

OBJECTIVES: The aim of this study was to assess the capacity of optimized multipoint pacing (MPP) over optimized cardiac resynchronization therapy (CRT), in terms of clinical, functional, and echocardiographic parameters among patients with dyssynchronous heart failure (HF). METHODS: Eighty patients (Caucasian, 77.5% male, 68.4 ± 10.1 years, and 53.8% ischemic cardiomyopathy) sequentially received optimized CRT and optimized MPP over 6- and 12-month periods in a single-arm clinical trial. Clinical, laboratory, and echocardiographic assessment was conducted at baseline and after the completion of each step. RESULTS: Significant additive effects of optimized MPP over optimized CRT were noted with regard to 6-min walking distance (baseline/optCRT/optMPP: 293 ± 120 m vs 367 ± 94 m vs 405 ± 129 m and p < 0.001), NYHA class (2.36 vs 2.19 vs 1.45 and p < 0.001), VTIlvot (14.25 ± 3.2 cm vs 16.2 ± 4 cm vs 17.5 ± 3.4 cm and p < 0.001), stroke volume (48 ± 13.5 ml vs 55 ± 15 ml vs 59 ± 15 ml and p < 0.001), left ventricular ejection fraction (LVEF) (29% ± 7.1% vs 33% ± 7.3% vs 37% ± 7.7% and p < 0.001), maximal left atrial volume (77.2 ± 34.2 ml vs 74.2 ± 39.5 ml vs 67.7 ± 32 ml and p = 0.02), pulmonary artery systolic pressure (35.9 mmHg vs 33.5 mmHg vs 31 mmHg and p < 0.001), and right ventricular strain (-8.3% ± 6.9% vs -8.8% ± 6.6% vs -11.8% ± 6.1% and p = 0.022). With regard to VAC, stroke work (SW), and CP as percentages of maximal, there was a significant difference detected as compared to baseline for both CRT and MPP. Additive effects persisted only if suitable MPP dipoles were present. Exploratory analysis revealed that ischemic cardiomyopathy continued to exhibit significant differences that favor MPP, whereas nonischemic cardiomyopathy had similar findings with regard to total left atrial strain and quality of life. CONCLUSIONS: Optimized MPP showed significant improvements in hemodynamic parameters and ventricular function in patients with HF over optimized CRT. The beneficial effect was more prominent in men and in those with rather reduced LVEF, consistent with findings that suggest a beneficial trend in VAC and CP with more homogeneous depolarization offered by optimized MPP.

Noninvasive risk factors for the prediction of inducibility on programmed ventricular stimulation in post-myocardial infarction patients with an ejection fraction ≥40% at risk for sudden cardiac arrest: Insights from the PRESERVE-EF study.

BACKGROUND: In the PRESERVE-EF study, a two-step sudden cardiac death (SCD) risk stratification approach to detect post-myocardial infarction (MI) patients with left ventricle ejection fraction (LVEF) ≥40% at risk for major arrhythmic events (MAEs) was used. Seven noninvasive risk factors (NIRFs) were extracted from a 24-h ambulatory electrocardiography (AECG) and a 45-min resting recording. Patients with at least one NIRF present were referred for invasive programmed ventricular stimulation (PVS) and inducible patients received an Implantable Cardioverter - Defibrillator (ICD). METHODS: In the present study, we evaluated the performance of the NIRFs, as they were described in the PRESERVE-EF study protocol, in predicting a positive PVS. In the PRESERVE-EF study, 152 out of 575 patients underwent PVS and 41 of them were inducible. For the present analysis, data from these 152 patients were analyzed. RESULTS: Among the NIRFs examined, the presence of signal averaged ECG-late potentials (SAECG-LPs) ≥ 2/3 and non-sustained ventricular tachycardia (NSVT) ≥1 eposode/24 h cutoff points were important predictors of a positive PVS study, demonstrating in the logistic regression analysis odds ratios 2.285 (p = .027) and 2.867 (p = .006), respectively. A simple risk score based on the above cutoff points in combination with LVEF < 50% presented high sensitivity but low specificity for a positive PVS. CONCLUSION: Cutoff points of NSVT ≥ 1 episode/24 h and SAECG-LPs ≥ 2/3 in combination with a LVEF < 50% were important predictors of inducibility. However, the final decision for an ICD implantation should be based on a positive PVS, which is irreplaceable in risk stratification.

Critical appraisal of technologies to assess electrical activity during atrial fibrillation: a position paper from the European Heart Rhythm Association and European Society of Cardiology Working Group on eCardiology in collaboration with the Heart Rhythm Society, Asia Pacific Heart Rhythm Society, Latin American Heart Rhythm Society and Computing in Cardiology.

We aim to provide a critical appraisal of basic concepts underlying signal recording and processing technologies applied for (i) atrial fibrillation (AF) mapping to unravel AF mechanisms and/or identifying target sites for AF therapy and (ii) AF detection, to optimize usage of technologies, stimulate research aimed at closing knowledge gaps, and developing ideal AF recording and processing technologies. Recording and processing techniques for assessment of electrical activity during AF essential for diagnosis and guiding ablative therapy including body surface electrocardiograms (ECG) and endo- or epicardial electrograms (EGM) are evaluated. Discussion of (i) differences in uni-, bi-, and multi-polar (omnipolar/Laplacian) recording modes, (ii) impact of recording technologies on EGM morphology, (iii) global or local mapping using various types of EGM involving signal processing techniques including isochronal-, voltage- fractionation-, dipole density-, and rotor mapping, enabling derivation of parameters like atrial rate, entropy, conduction velocity/direction, (iv) value of epicardial and optical mapping, (v) AF detection by cardiac implantable electronic devices containing various detection algorithms applicable to stored EGMs, (vi) contribution of machine learning (ML) to further improvement of signals processing technologies. Recording and processing of EGM (or ECG) are the cornerstones of (body surface) mapping of AF. Currently available AF recording and processing technologies are mainly restricted to specific applications or have technological limitations. Improvements in AF mapping by obtaining highest fidelity source signals (e.g. catheter-electrode combinations) for signal processing (e.g. filtering, digitization, and noise elimination) is of utmost importance. Novel acquisition instruments (multi-polar catheters combined with improved physical modelling and ML techniques) will enable enhanced and automated interpretation of EGM recordings in the near future.

ESC Working Group on e-Cardiology Position Paper: accuracy and reliability of electrocardiogram monitoring in the detection of atrial fibrillation in cryptogenic stroke patients : In collaboration with the Council on Stroke, the European Heart Rhythm Association, and the Digital Health Committee.

The role of subclinical atrial fibrillation as a cause of cryptogenic stroke is unambiguously established. Long-term electrocardiogram (ECG) monitoring remains the sole method for determining its presence following a negative initial workup. This position paper of the European Society of Cardiology Working Group on e-Cardiology first presents the definition, epidemiology, and clinical impact of cryptogenic ischaemic stroke, as well as its aetiopathogenic association with occult atrial fibrillation. Then, classification methods for ischaemic stroke will be discussed, along with their value in providing meaningful guidance for further diagnostic efforts, given disappointing findings of studies based on the embolic stroke of unknown significance construct. Patient selection criteria for long-term ECG monitoring, crucial for determining pre-test probability of subclinical atrial fibrillation, will also be discussed. Subsequently, the two major classes of long-term ECG monitoring tools (non-invasive and invasive) will be presented, with a discussion of each method's pitfalls and related algorithms to improve diagnostic yield and accuracy. Although novel mobile health (mHealth) devices, including smartphones and smartwatches, have dramatically increased atrial fibrillation detection post ischaemic stroke, the latest evidence appears to favour implantable cardiac monitors as the modality of choice; however, the answer to whether they should constitute the initial diagnostic choice for all cryptogenic stroke patients remains elusive. Finally, institutional and organizational issues, such as reimbursement, responsibility for patient management, data ownership, and handling will be briefly touched upon, despite the fact that guidance remains scarce and widespread clinical application and experience are the most likely sources for definite answers.