Heart rhythm最新文献

Background: Although drug interactions between clarithromycin/erythromycin/fluconazole and direct oral anticoagulants (DOACs) are mechanistically plausible, it is uncertain whether they are clinically relevant.

Objective: To investigate the association between co-prescribed DOACs and antimicrobials and bleeding, cardiovascular disease and mortality.

Methods: We identified DOAC users in the Clinical Practice Research Datalink Aurum from 1/1/2011-29/3/2021. We used a cohort design to estimate hazard ratios for bleeding outcomes (intracranial bleeding, gastrointestinal bleeding, other bleeding), comparing DOACs+clarithromycin/erythromycin/fluconazole users with DOACs users not receiving these antimicrobials. Cardiovascular outcomes were ischaemic stroke, myocardial infarction, venous thromboembolism, cardiovascular mortality and all-cause mortality. A 6-parameter case-crossover design comparing odds of exposure to different drug initiation patterns for all outcomes in hazard window versus referent window within an individual was also conducted.

Results: Of 483,815 DOAC users, we identified 21,701 co-prescribed clarithromycin, 4,532 co-prescribed erythromycin and 4,840 co-prescribed fluconazole. We observed an increased risk of gastrointestinal bleeding over 7-days following co-prescription of DOAC+erythromycin versus DOAC alone (HR:3.66; 99%CI:1.27-10.51), with wide CIs in case-crossover analysis. No evidence of increased risk of bleeding outcomes was seen for DOAC+clarithromycin/fluconazole in cohort and case-crossover analyses. For cardiovascular outcomes, compared with DOAC alone, an increased risk of cardiovascular mortality with DOAC+clarithromycin(HR:3.36; 99%CI:1.73-6.52) and increased risk of all-cause mortality with DOAC+clarithromycin/erythromycin/fluconazole were observed in cohort analysis. However, similar risks were found when initiating erythromycin/fluconazole with and without DOAC.

Conclusion: We found no strong evidence of increased risks of bleeding and cardiovascular outcomes in DOACs+clarithromycin/fluconazole/erythromycin users except a possible short-term increased risk of gastrointestinal bleeding in DOACs+erythromycin users.

Background: Although smartphone-based devices have been developed to record 1-lead ECG, existing solutions for automatic atrial fibrillation (AF) detection often has poor positive predictive value.

Objective: This study aimed to validate a cloud-based deep learning platform for automatic AF detection in a large cohort of patients using 1-lead ECG records.

Methods: We analyzed 8,528 patients with 30-second ECG records from a single-lead handheld ECG device. Ground truth for AF presence was established through a benchmark algorithm and expert manual labeling. The Willem Artificial Intelligence (AI) platform, not trained on these ECGs, was used for automatic arrhythmia detection, including AF. A rules-based algorithm was also used for comparison. An expert cardiology committee reviewed false positives and negatives and performance metrics were computed.

Results: The AI platform achieved an accuracy of 96.1% (initial labels) and 96.4% (expert review), with sensitivities of 83.3% and 84.2%, and specificities of 97.3% and 97.6%, respectively. The positive predictive value was 75.2% and 78.0%, and the negative predictive value was 98.4%. Performance of the AI platform largely exceeded the performance of the rules-based algorithm for all metrics. The AI also detected other arrhythmias, such as premature ventricular complexes, premature atrial complexes along with 1-degree atrioventricular blocks.

Conclusions: The result of this external validation indicates that the AI platform can match cardiologist-level accuracy in AF detection from 1-lead ECGs. Such tools are promising for AF screening and has the potential to improve accuracy in non-cardiology expert healthcare professional interpretation and trigger further tests for effective patient management.

Background: Brugada syndrome (BrS) is a genetic heart disease that predisposes individuals to ventricular arrhythmias and sudden cardiac death. Although implantable cardioverter-defibrillators (ICDs) and quinidine are primary treatments, recurrent BrS-triggered ventricular arrhythmias can persist. In this setting, epicardial substrate ablation has emerged as a promising alternative for symptomatic patients.

Objective: Evaluate the effectiveness and safety of epicardial substrate ablation in patients with BrS.

Methods: In this single-arm meta-analysis, we systematically searched PubMed, Embase, and Cochrane databases following PRISMA guidelines for studies including BrS patients with epicardial substrate ablation. Data was extracted, and statistical analysis was performed using random-effects modeling for proportional meta-analysis.

Results: 13 cohort studies comprising 555 BrS patients were included. The mean age at enrollment was 42.6 ± 12.3 years; 82.7% were males, and 50% exhibited spontaneous type 1 Brugada ECG pattern. Pooled analysis demonstrated resolution of the type 1 pattern in 91% of the cases (95% CI 80-98%; I²=86%) and elimination of abnormal electrograms in 91% (95% CI 78-99%; I²=74%). Rates of recurrent VT/VF and appropriate ICD therapies during post-ablation follow-up were 12% (95% CI 4-21%; I²=86%) and 8% (95% CI 2-18%; I²=87%), respectively.

Conclusions: Epicardial substrate ablation shows promise for BrS patients experiencing BrS-triggered ventricular arrhythmias, offering therapeutic efficacy with an acceptable safety profile. High heterogeneity among studies highlights the need for further research and standardized protocols.

Background: Better risk stratification is needed to evaluate patients with non-ischemic cardiomyopathy (NICM) for prophylactic implantable cardioverter-defibrillators (ICD). Growing evidence suggests cardiac magnetic resonance imaging (CMR) may be useful in this regard.

Objective: We aimed to determine if late-gadolinium enhancement (LGE) seen on CMR (dichotomized as none/minimal <2% vs significant ≥2%) predicts appropriate ICD therapies (primary endpoint) and/or all-cause mortality/transplant/left-ventricular assist device (LVAD) implantation (secondary endpoint) in NICM patients.

Methods: We identified 344 patients with NICM who underwent primary prevention ICD implantation at Cleveland Clinic between 2003-2021 with CMR within 12 months before implant. LGE was calculated as percentage myocardium with pixel intensity ≥5 standard deviations higher than that of reference myocardium. Endpoints were adjudicated retrospectively by chart review.

Results: 125 of 344 patients (36%) had none/minimal LGE and 219 (64%) had significant LGE. Over a median follow-up of 61 months, 53 patients (24%) with significant LGE vs 10 (8%) with none/minimal LGE met the primary endpoint, and 56 patients (26%) vs 21 (17%) met the secondary endpoint, respectively. Significant LGE predicted the primary outcome in multivariable competing-risks regression (hazard ratio 2.99, 95% CI 1.48-6.02, p=0.002), but did not predict the secondary outcome in multivariable Cox regression (hazard ratio 1.34, 95% CI 0.78-2.29, p=0.287).

Conclusion: In patients with NICM and a primary prevention ICD, LGE ≥2% is predictive of appropriate device therapies but not all-cause mortality/LVAD/transplant. LGE may be a relatively specific predictor of sudden cardiac arrest risk and therefore could potentially be used during evaluation for prophylactic ICD implantation.

Background: People with frailty have increased prevalence and incidence of atrial fibrillation (AF).

Objective: The study aimed to further investigate the association of long-term changes in frailty with risk of new-onset AF. Its associations with heart failure (HF), coronary heart disease (CHD), and stroke were also evaluated as a secondary aim.

Methods: Over 50,000 participants from UK Biobank cohort were included, with frailty index (FI) data and free of AF, HF, CHD or stroke in baseline and follow-up assessments. Frailty status of the participants was categorized into non-frail, pre-frail and frail based on their FI scores. FI in baseline and follow-ups are used to calculate the trajectories of frailty (ΔFI).

Results: During a median of 5.1 years of follow-up from the final assessment, 1729 cases of AF were recorded. Frailty trajectory analysis showed that even a 0.01 point/year increase in ΔFI was associated with 14% (95% CI 1.08-1.20) higher risk of AF, independent of baseline FI after adjusting for potential confounders. Compared with maintained non-frail participants, those with sustained frail status had the highest risk of incident AF (HR 1.95, 1.61-2.36). The risk declined by 30% (95% CI 0.53-0.94) when frail participants regressed to non-frail or pre-frail status, compared with sustained frail participants. These associations were similar in HF and CHD, however, not significant in stroke.

Conclusion: In middle-aged and elderly individuals, frailty remission or non-frailty maintenance was associated with lower risk of AF, HF and CHD compared to persistent frailty, regardless of prior frailty status and established risk factors.

Background: There is limited information on protective factors related to atrioventricular (AV) block.

Objective: This study examines the association between accelerometer-derived moderate-to-vigorous physical activity (MVPA) and AV block in healthy elderly individuals.

Methods: A total of 23,590 UK Biobank participants ≥60 years involved in a wrist-worn accelerometer study with no history of hypertension, diabetes mellitus, dyslipidemia, and coronary heart disease were analyzed. The associations of MVPA with primary (second- or third-degree AV block) and secondary outcome (third-degree AV block, pacemaker implantation) were evaluated by Cox regression analysis. The associations of MVPA with electrocardiogram parameters were evaluated by linear regression analysis.

Results: The mean age was 63.8 ± 2.8 years, and 57.4% were women. During the median follow-up period of 6.1 years, 115 primary outcome events occurred. As compared with quintile 1 (<89 min/week), those in quintile 4 (280-449 min/week) had a 63% lower incidence of primary outcome (HR: 0.37, 95% CI: 0.19 to 0.73, P=0.004); however, the result was attenuated in quintile 5. This pattern was consistently observed in the relationship between MVPA and third-degree AV block (quintile 4 vs quintile 1: HR: 0.29, 95% CI: 0.11 to 0.74, P=0.010) and pacemaker implantation. MVPA per 150 min/week increase was independently negatively associated with normalized PQ interval (msec) (β: ‒2.13, 95% CI: ‒3.03 to ‒1.24, P<0.001).

Conclusions: In the healthy elderly population, MVPA was associated with a lower risk of second- or third-degree AV block, which correlates with the reduction of normalized PQ interval. However, excessive MVPA attenuated the results.

Background: Spontaneously occurring life threatening reentrant arrhythmias result when a propagating premature beat encounters a region with significant dispersion of refractoriness. Although localized structural tissue heterogeneities and prescribed cell functional gradients have been incorporated into computational electrophysiological models, a quantitative framework for the evolution from normal to abnormal behavior that occurs via disease is lacking.

Objective: The purpose of this study was to develop a probabilistic modeling framework that represents the complex interplay of cell function and tissue structure in health and disease which predicts the emergence of premature beats and the initiation of reentry.

Methods: An action potential model of the rabbit was developed using data-driven uncertainty characterization as done previously. A novel tissue model using the discrete cell monodomain equations was developed by implementing cellular uncertainty as a random spatial field.

Results: Cellular action potentials exhibited a wide range of duration, and even a variety of behaviors, with 67% exhibiting normal repolarization; 27% displaying early after depolarizations; and 6% showing repolarization failure. Nevertheless, simulations in tissue resulted in localized synchronized repolarization. Thus, cellular variability provided "tissue-level robustness" and premature beats and reentry induction were never observed even with abnormalities in cell function (I_Kr block) or tissue structure (increased tissue resistance). Alterations of both cell function and tissue structure were necessary for the generation of premature beats and arrhythmia initiation.

Conclusion: Once extended to whole hearts and validated for a specific context, this modeling framework provides a means to predict the probability of the initiation of life-threating arrhythmias.

Background: A significant proportion of patients with isolated atrial flutter (AFL) will develop atrial fibrillation (AF) following cavotricuspid isthmus (CTI) ablation.

Objective: To determine whether concomitant pulmonary vein isolation (PVI) could reduce the incidence of new-onset atrial fibrillation (NOAF) in the setting of inducible AF following CTI ablation.

Methods: A total of 275 consecutive patients with isolated AFL who successfully underwent CTI ablation were included. Patients were stratified into the induced AF group (55 patients) and the non-induced AF group (220 patients) based on the inducibility of AF. Subsequently, the induced AF group was randomly divided into PVI group (28 patients) and non-PVI (27 patients) group.

Results: During 27.0±6.0 months of follow-up, the PVI group [(7.1% vs. 51.9%, p<0.001), HR 0.103, 95%CI. for HR (0.038, 0.278), p<0.001] and non-induced AF group [(13.2% vs. 51.9%, p<0.001), HR 0.207, 95%CI. for HR (0.073, 0.586), p<0.001] exhibited substantially lower incidence and risk of NOAF compared to the non-PVI group. Kaplan-Meier analysis showed that history of hypertension, cardiovascular disease, heart failure and larger BMI, larger LAd, lower LVEF were identified predictors of NOAF.

Conclusion: Inducibility of AF during CTI ablation is positively associated with an increased risk of NOAF, while concomitant PVI for induced AF can significantly reduce the incidence of NOAF.