The association between antithrombotic drug regimen changes and clinical outcomes after stroke in atrial fibrillation.

BACKGROUND: The impact of post-stroke antithrombotic regimen in atrial fibrillation (AF) is uncertain. OBJECTIVE: To describe antithrombotic therapy prescribing patterns following ischemic stroke, and its impact on outcomes. METHODS: A total of 23,165 AF patients experiencing ischemic stroke were identified. Subsequent post-stroke events included recurrent ischemic stroke, intracranial hemorrhage (ICH), major bleeding, mortality, and composite outcomes. RESULTS: Among those who were non-anticoagulated before a stroke, 33.5% remained non-anticoagulated and 39.2% were prescribed only antiplatelets (AP) post-stroke. Compared to NOACs post-stroke, there was a significant increase in ischemic stroke and mortality in non-anticoagulated (aHRs 2.09 and 3.92) and antiplatelet users (aHRs 1.32 and 1.28). Post-stroke warfarin was associated with a significantly incresaed risk of major bleeding compared to NOACs (aHR 1.23). Among 769 patients receiving NOACs before stroke and continuing NOAC post-stroke, those switching to a different NOAC were associated with significantly higher risk of ischemic stroke (aHR 2.07) and composite outcomes (aHRs 1.36-1.85) with no difference in ICH, major bleeding or mortality compared to those on the same NOAC post-stroke. Among patients receiving NOACs before stroke, the risks of clinical events were similar between patients on NOACs alone and those on NOAC plus AP post-stroke. CONCLUSIONS: NOAC alone post-stroke was associated with a better clinical outcome compared to non-anticoagulation, AP or warfarin. Among patients already taking NOACs before stroke, the addition of AP didn't confer additional benefits compared to NOACs alone. A change of NOAC types post-stroke was associated with a two-fold higher risk of ischemic stroke and composite outcomes.

Impact of proximity of left atrium to descending aorta on left inferior pulmonary vein triggers or drivers of atrial fibrillation: A risk score model.

BACKGROUND: Prior studies have investigated cardiac anatomy and clinical parameters as predictors for pulmonary vein and non-pulmonary vein triggers. OBJECTIVE: We aimed to assess the link between the descending aorta to left inferior pulmonary vein (Dao-LIPV) distance and the occurrence of triggers and drivers in atrial fibrillation (AF) ablation procedures. METHODS: Drug-refractory AF patients who underwent first-time index catheter ablation from January 2010 to December 2019 were retrospectively assembled. The Dao-LIPV distance was measured from preablation pulmonary vein computed tomography. Patients were assigned to groups on the basis of the presence of LIPV triggers or drivers. Multivariate logistic regression was used to identify risk factors. RESULTS: A total of 886 consecutive patients with drug-refractory AF were studied, and 63 (7.1%) patients were identified to have LIPV triggers or drivers. The Dao-LIPV distance had a better predictive performance (area under the curve, 0.70) compared with persistent AF (area under the curve, 0.57). Multivariate logistic regression analysis showed that Dao-LIPV distance ≤2.5 mm (odds ratio, 3.96; 95% CI, 2.15-7.29; P < .001) and persistent AF (odds ratio, 1.73; 95% CI, 1.02-2.94]; P = .044) were independent predictors for the presence of LIPV triggers or drivers. A risk score model was established to predict the probability of LIPV triggers or drivers with persistent AF (10.2%), Dao-LIPV distance ≤2.5 mm (11.4%), and both (15.0%). CONCLUSION: The proximity of the Dao-LIPV was correlated to the presence of LIPV triggers or drivers. We developed a risk score model indicating that persistent AF and Dao-LIPV distances ≤2.5 mm significantly increase the risk of LIPV triggers or drivers, aiding electrophysiologists in preparing for and performing catheter ablation more effectively.

Ibrutinib, a Bruton's tyrosine kinase inhibitor, regulates ventricular electromechanical activities and enhances arrhythmogenesis.

BACKGROUND: Ibrutinib, a Bruton's tyrosine kinase inhibitor used in cancer therapy, exerts ventricular proarrhythmic effects; however, the underlying mechanisms remain unclear. Excitation-contraction coupling (E-C) disorders are pivotal for the genesis of ventricular arrhythmias (VAs), which arise mainly from the right ventricular outflow tract (RVOT). In this study, we aimed to comprehensively investigate whether ibrutinib regulates the electromechanical activities of the RVOT, leading to enhanced arrhythmogenesis, and explore the underlying mechanisms. METHODS: We utilized conventional microelectrodes to synchronously record electrical and mechanical responses in rabbit RVOT tissue preparations before and after treatment with ibrutinib (10, 50, and 100 nM) and investigated their electromechanical interactions and arrhythmogenesis during programmed electrical stimulation. The fluorometric ratio technique was used to measure intracellular calcium concentration in isolated RVOT myocytes. RESULTS: Ibrutinib (10-100 nM) shortened the action potential duration. Ibrutinib at 100 nM significantly increased pacing-induced ventricular tachycardia (VT) (from 0% to 62.5%, n = 8, p = 0.025). Comparisons between pacing-induced VT and non-VT episodes demonstrated that VT episodes had a greater increase in contractility than that of non-VT episodes (402.1 ± 41.4% vs. 232.4 ± 29.2%, p = 0.003). The pretreatment of ranolazine (10 µM, a late sodium current blocker) prevented the occurrence of ibrutinib-induced VAs. Ibrutinib (100 nM) increased late sodium current, reduced intracellular calcium transients, and enhanced calcium leakage in RVOT myocytes. CONCLUSION: Ibrutinib increased the risk of VAs in the RVOT due to dysregulated electromechanical responses, which can be attenuated by ranolazine or apamin.

Signal-averaged electrocardiography as a noninvasive tool for evaluating the ventricular substrate in patients with nonischemic cardiomyopathy: reassessment of an old tool.

Introduction: Signal-averaged electrocardiography (SAECG) provides diagnostic and prognostic information regarding cardiac diseases. However, its value in other nonischemic cardiomyopathies (NICMs) remains unclear. This study aimed to investigate the role of SAECG in patients with NICM. Methods and results: This retrospective study included consecutive patients with NICM who underwent SAECG, biventricular substrate mapping, and ablation for ventricular arrhythmia (VA). Patients with baseline ventricular conduction disturbances were excluded. Patients who fulfilled at least one SAECG criterion were categorized into Group 1, and the other patients were categorized into Group 2. Baseline and ventricular substrate characteristics were compared between the two groups. The study included 58 patients (39 men, mean age 50.4 ± 15.5 years), with 34 and 24 patients in Groups 1 and 2, respectively. Epicardial mapping was performed in eight (23.5%) and six patients (25.0%) in Groups 1 and 2 (p = 0.897), respectively. Patients in Group 1 had a more extensive right ventricular (RV) low-voltage zone (LVZ) and scar area than those in Group 2. Group 1 had a larger epicardial LVZ than Group 2. Epicardial late potentials were more frequent in Group 1 than in Group 2. There were more arrhythmogenic foci within the RV outflow tract in Group 1 than in Group 2. There was no significant difference in long-term VA recurrence. Conclusion: In our NICM population, a positive SAECG was associated with a larger RV endocardial scar, epicardial scar/late potentials, and a higher incidence of arrhythmogenic foci in the RV outflow tract.

Comparison of dexmedetomidine versus propofol sedation on microcirculation and organ injuries in critically ill surgical patients: A randomized controlled pilot study.

BACKGROUND: Recent studies have shown that dexmedetomidine may improve microcirculation and prevent organ failure. However, most evidence was obtained from experimental animals and patients receiving cardiac surgery with cardiopulmonary bypass. This study aimed to investigate the effect of dexmedetomidine on microcirculation and organ injuries in critically ill general surgical patients. METHODS: In this prospective randomized trial, patients admitted to the surgical intensive care unit after general surgery were enrolled and randomly allocated to the dexmedetomidine or propofol groups. Patients received continuous dexmedetomidine or propofol infusions to meet their requirement of sedation according to their grouping. At each time point, sublingual microcirculation images were obtained using the incident dark field video microscope. RESULTS: Overall, 60 patients finished the trial and were analyzed. Microcirculation parameters did not differ significantly between two groups. Heart rate at 4 h after ICU admission and mean arterial pressures at 12 h and 24 h after ICU admission were lower in the dexmedetomidine group than in the propofol group. At 24 h, serum aspartate aminotransferase (41 (25-118) vs 86 (34-129) U/L, p = 0.035) and alanine aminotransferase (50 (26-160) vs 68 (35-172) U/L, p = 0.019) levels were significantly lower in the dexmedetomidine group than in the propofol group. CONCLUSION: Microcirculation parameters did not differ significantly between the dexmedetomidine and propofol groups. At 24 h after ICU admission, serum liver enzyme levels were lower in patients receiving dexmedetomidine as compared to propofol.

Relationship Between Subjective Questionnaires and Videofluoroscopy of Dysphagia Evaluation: A Systematic Review and Meta-Analysis.

BACKGROUND: Early detection of dysphagia is important for preventing aspiration pneumonia. Although videofluoroscopy is currently the primary diagnostic tool for dysphagia, access to this tool may be limited because of radiation exposure risk, high cost, and other factors. PURPOSE: In this study, a meta-analysis was used to determine the strength of the correlation between dysphagia detection outcomes obtained using subjective questionnaires and videofluoroscopy. METHODS: The PubMed and Embase databases were searched for original articles up to December 2022. Studies published in English that used cross-sectional designs to assess the correlation between subjective questionnaires and videofluoroscopy were considered eligible for inclusion. The search terms used included "dysphagia," "questionnaire," and "videofluoroscopy." Two reviewers critically appraised and extracted the correlation coefficient r values. In addition, a random-effects meta-analysis was conducted. The Q statistic was used to assess the heterogeneity among the included studies. Publication bias was checked using the funnel plot and Egger's tests. Multilevel analysis was used to determine sensitivity to consider within-study correlations. In addition, subgroup analyses were conducted based on type of questionnaire, head and neck cancer, and English-speaking regions. RESULTS: The meta-analysis included five studies and 856 patients using the Eating Assessment Tool-10 and one study and 27 patients using the Sydney Swallow Questionnaire. The results of the random-effects meta-analysis showed a moderate relationship between the subjective questionnaires and videofluoroscopy ( r = .35, 95% CI [0.20, 0.48]). Similar results were also obtained using multilevel analysis ( r = .34, 95% CI [0.25, 0.42]). No publication bias was found for any of the studies ( p = .88). In the subgroup analyses, a moderate relationship between Eating Assessment Tool-10 and videofluoroscopy ( r = .31, 95% CI [0.19, 0.42]) and an ultrahigh relationship between Sydney Swallow Questionnaire and video-fluoroscopy ( r = .74, 95% CI [0.50, 0.87]) were found. Furthermore, moderate associations were observed within each head and neck cancer and English-speaking regions subgroup. However, no significant differences were found between these two subgroups. CONCLUSIONS: These results indicate the subjective questionnaires considered in this study share a moderate relationship with videofluoroscopy. Subjective questionnaires may be used as an auxiliary tool by nurses and homecare givers for the early assessment of dysphagia risk in patients.

Use of artificial intelligence and I-Score for prediction of recurrence before catheter ablation of atrial fibrillation.

BACKGROUND: Based solely on pre-ablation characteristics, previous risk scores have demonstrated variable predictive performance. This study aimed to predict the recurrence of AF after catheter ablation by using artificial intelligence (AI)-enabled pre-ablation computed tomography (PVCT) images and pre-ablation clinical data. METHODS: A total of 638 drug-refractory paroxysmal atrial fibrillation (AF) patients undergone ablation were recruited. For model training, we used left atria (LA) acquired from pre-ablation PVCT slices (126,288 images). A total of 29 clinical variables were collected before ablation, including baseline characteristics, medical histories, laboratory results, transthoracic echocardiographic parameters, and 3D reconstructed LA volumes. The I-Score was applied to select variables for model training. For the prediction of one-year AF recurrence, PVCT deep-learning and clinical variable machine-learning models were developed. We then applied machine learning to ensemble the PVCT and clinical variable models. RESULTS: The PVCT model achieved an AUC of 0.63 in the test set. Various combinations of clinical variables selected by I-Score can yield an AUC of 0.72, which is significantly better than all variables or features selected by nonparametric statistics (AUCs of 0.66 to 0.69). The ensemble model (PVCT images and clinical variables) significantly improved predictive performance up to an AUC of 0.76 (sensitivity of 86.7% and specificity of 51.0%). CONCLUSIONS: Before ablation, AI-enabled PVCT combined with I-Score features was applicable in predicting recurrence in paroxysmal AF patients. Based on all possible predictors, the I-Score is capable of identifying the most influential combination.

Which dose of apixaban is suitable for Asian patients with atrial fibrillation who have a serum creatinine < 1.5 mg/dL but an estimated glomerular filtration rate < 50 mL/min?

Introduction: Reduced-dose (Low-dose [LD]) apixaban is recommended in patients with atrial fibrillation (AF) who fulfill 2 of 3 criteria: age ≥ 80 years, body weight ≤ 60 kg, and a serum creatinine (sCr) ≥ 1.5 mg/dl. However, the suitable (appropriate) dose for Asian patients who have a sCr < 1.5 mg/dl but an estimated glomerular filtration rate (eGFR) < 50 mL/min is unknown. Methods: This is a retrospective study using the Chang Gung Memorial hospital medical database in Taiwan. A total of 13,508 AF patients receiving oral anticoagulants (OACs) from 2012 to 2018 were reviewed and 1595 patients with a sCr < 1.5 mg/dL and an eGFR < 50 mL/min who met 1 criterion of dose reduction of apixaban other than sCr (that is, age ≥ 80 years or body weight < 60 kg) were identified. Clinical outcomes were compared between LD and SD apixaban versus warfarin. Results: Their OACs use was as follows: 343 receiving apixaban (128 patients on standard dose [SD] and 215 on LD), 174 receiving warfarin, and 1078 on other NOACs. Patients with an eGFR < 50 mL/min had higher risk of mortality (adjusted hazard ratio [aHR], 1.264; 95 % confidence interval [CI], 1.086-1.472) and composite endpoint of 'ischemic stroke/systemic embolism (IS/SE) or major bleeding or mortality (aHR, 1.202; 95 % CI, 1.056-1.370) compared to those with an eGFR ≥ 50 mL/min whereas the risk of IS/SE and major bleeding were similar. LD apixaban was associated with lower risk of composite endpoint of IS/SE or major bleeding (aHR, 0.567; 95 % CI, 0.331 - 0.972), mortality (aHR, 0.336; 95 % CI, 0.138 - 0.815), and 'IS/SE or major bleeding or mortality (aHR, 0.551; 95 % CI, 0343 - 0.886) compared to warfarin while the risk was comparable between SD apixaban and warfarin (aHR, 0.745; 95 % CI, 0.402 - 1.378; aHR, 0.407; 95 % CI, 0.145 - 1.143; aHR, 0.619; 95 % CI, 0.354 - 1.084, respectively). Conclusion: In patients with sCr < 1.5 mg/dL and eGFR < 50 mL/min, SD and LD apixaban were comparable in the prevention of IS/SE, but LD apixaban was superior in reducing the composite endpoint of 'IS/SE or major bleeding or mortality'. Therefore, LD apixaban might be a preferred dose for this population.

Patients with first-episode psychosis in northern Taiwan: neurocognitive performance and niacin response profile in comparison with schizophrenia patients of different familial loadings and relationship with clinical features.

BACKGROUND: Examining patients with first-episode psychosis (FEP) provides opportunities to better understand the mechanism underlying these illnesses. By incorporating quantitative measures in FEP patients, we aimed to (1) determine the baseline distribution of clinical features; (2) examine the impairment magnitude of the quantitative measures by comparing with external controls and then the counterparts of schizophrenia patients of different familial loadings; and (3) evaluate whether these quantitative measures were associated with the baseline clinical features. METHODS: Patients with FEP were recruited from one medical center, two regional psychiatric centers, and two private clinics in northern Taiwan with clinical features rated using the Positive and Negative Syndrome Scale (PANSS) and Personal and Social Performance (PSP) scale. Quantitative measurements included the Continuous Performance Test (CPT), Wisconsin Card Sorting Test (WCST), niacin response abnormality (NRA), and minor physical anomalies and craniofacial features (MPAs). To evaluate the relative performance of the quantitative measures in our FEP patients, four external comparison groups from previous studies were used, including three independent healthy controls for the CPT, WCST, and NRA, respectively, and one group of treatment-resistant schizophrenia patients for the MPAs. Additionally, patients from simplex families and patients from multiplex families were used to assess the magnitude of FEP patients' impairment on the CPT, WCST, and NRA. RESULTS: Among the 80 patients with FEP recruited in this study (58% female, mean age = 25.6 years, mean duration of untreated psychosis = 132 days), the clinical severity was mild to moderate (mean PANSS score = 67.3; mean PSP score = 61.8). Patients exhibited both neurocognitive and niacin response impairments (mean Z-scores: -1.24 for NRA, - 1.06 for undegraded d', - 0.70 for degraded d', - 0.32 for categories achieved, and 0.44 for perseverative errors) but did not show MPAs indicative of treatment resistance. Among these quantitative measures, three of the four neurocognitive indices were correlated with the baseline clinical features, whereas NRA did not show such correlation. CONCLUSIONS: This FEP study of Taiwanese patients revealed the presence of neurocognitive performance and niacin response and their different relationships with clinical features, rendering this sample useful for future follow-up and incorporation of multiomics investigation.

Feasibility of Auto-Quantified Epicardial Adipose Tissue in Predicting Atrial Fibrillation Recurrence After Catheter Ablation.

BACKGROUND: The aim of this study was to build an auto-segmented artificial intelligence model of the atria and epicardial adipose tissue (EAT) on computed tomography (CT) images, and examine the prognostic significance of auto-quantified left atrium (LA) and EAT volumes for AF. METHODS AND RESULTS: This retrospective study included 334 patients with AF who were referred for catheter ablation (CA) between 2015 and 2017. Atria and EAT volumes were auto-quantified using a pre-trained 3-dimensional (3D) U-Net model from pre-ablation CT images. After adjusting for factors associated with AF, Cox regression analysis was used to examine predictors of AF recurrence. The mean (±SD) age of patients was 56±11 years; 251 (75%) were men, and 79 (24%) had non-paroxysmal AF. Over 2 years of follow-up, 139 (42%) patients experienced recurrence. Diabetes, non-paroxysmal AF, non-pulmonary vein triggers, mitral line ablation, and larger LA, right atrium, and EAT volume indices were linked to increased hazards of AF recurrence. After multivariate adjustment, non-paroxysmal AF (hazard ratio [HR] 0.6; 95% confidence interval [CI] 0.4-0.8; P=0.003) and larger LA-EAT volume index (HR 1.1; 95% CI 1.0-1.2; P=0.009) remained independent predictors of AF recurrence. CONCLUSIONS: LA-EAT volume measured using the auto-quantified 3D U-Net model is feasible for predicting AF recurrence after CA, regardless of AF type.

Catheter ablation in patients with atrial fibrillation and dilated cardiomyopathy.

Introduction: Catheter ablation is an effective and safe strategy for treating atrial fibrillation patients. Nevertheless, studies on the long-term outcomes of catheter ablation in patients with dilated cardiomyopathy are limited. This study aimed to assess the electrophysiological characteristics of atrial fibrillation patients with dilated cardiomyopathy and compare the long-term clinical outcomes between patients undergoing catheter ablation and medical therapy. Method: Patient baseline characteristics and electrophysiological parameters were examined to identify the predictors of atrial fibrillation recurrence following catheter ablation. The clinical outcomes of catheter ablation and medical therapy were compared using the propensity score matched method. Results: A total of 343 patients were enrolled, with 46 in the catheter ablation group and 297 in the medical therapy group. Among the catheter ablation group, 58.7% (n = 27) had persistent atrial fibrillation. The recurrence rate of atrial arrhythmia was 30.4% (n = 14) after an average follow-up duration of 7.7 years following catheter ablation. The only predictive factor for atrial fibrillation recurrence after catheter ablation was the left atrial diameter. When compared to medical therapy, catheter ablation demonstrated significantly better outcomes in terms of overall survival, freedom from heart failure hospitalization, improvement in left ventricular ejection fraction, and a greater reduction in left ventricular diameter and left atrial diameter after propensity score matching. Conclusions: Therefore, catheter ablation proves to be effective in providing long-term control of atrial fibrillation in patients with dilated cardiomyopathy. In addition to standard heart failure care, catheter ablation significantly enhanced both morbidity and mortality outcomes and reversed structural remodeling when compared to heart failure medication alone.

Catheter Ablation in Arrhythmic Cardiac Diseases: Endocardial and Epicardial Ablation.

Arrhythmogenic cardiomyopathy (ACM) is a group of arrhythmogenic disorders of the myocardium that are not caused by ischemic, hypertensive, or valvular heart disease. The clinical manifestations of ACMs may overlap those of dilated cardiomyopathy, complicating the differential diagnosis. In several ACMs, ventricular tachycardia (VT) has been observed at an early stage, regardless of the severity of the disease. Therefore, preventing recurrences of VT can be a clinical challenge. There is a wide range of efficacy and side effects associated with the use of antiarrhythmic drugs (AADs) in the treatment of VT. In addition to AADs, patients with ACM and ventricular tachyarrhythmias may benefit from catheter ablation, especially if they are drug-refractory. The differences in pathogenesis between the various types of ACMs can lead to heterogeneous distributions of arrhythmogenic substrates, non-uniform ablation strategies, and distinct ablation outcomes. Ablation has been documented to be effective in eliminating ventricular tachyarrhythmias in arrhythmogenic right ventricular dysplasia (ARVC), sarcoidosis, Chagas cardiomyopathy, and Brugada syndrome (BrS). As an entity that is rare in nature, ablation for ventricular tachycardia in certain forms of ACM may only be reported through case reports, such as amyloidosis and left ventricular noncompaction. Several types of ACMs, including ARVC, sarcoidosis, Chagas cardiomyopathy, BrS, and left ventricular noncompaction, may exhibit diseased substrates within or adjacent to the epicardium that may be accountable for ventricular arrhythmogenesis. As a result, combining endocardial and epicardial ablation is of clinical importance for successful ablation. The purpose of this article is to provide a comprehensive overview of the substrate characteristics, ablation strategies, and ablation outcomes of various types of ACMs using endocardial and epicardial approaches.