Lower contact force predicts right pulmonary vein carina breakthrough after ablation index-guided pulmonary vein isolation using high-power short-duration.

INTRODUCTION: Carina breakthrough (CB) at the right pulmonary vein (RPV) can occur after circumferential pulmonary vein isolation (PVI) due to epicardial bridging or transient tissue edema. High-power short-duration (HPSD) ablation may increase the incidence of RPV CB. Currently, the surrogate of ablation parameters to predict RPV CB is not well established. This study investigated predictors of RPV CB in patients undergoing ablation index (AI)-guided PVI with HPSD. METHODS: The study included 62 patients with symptomatic atrial fibrillation (AF) who underwent AI-guided PVI using HPSD. Patients were categorized into two groups based on the presence or absence of RPV CB. Lesions adjacent to the RPV carina were assessed, and CB was confirmed through residual voltage, low voltage along the ablation lesions, and activation wavefront propagation. RESULTS: Out of the 62 patients, 21 (33.87%) experienced RPV CB (Group 1), while 41 (66.13%) achieved first-pass RPV isolation (Group 2). Despite similar AI and HPSD, patients with RPV CB had lower contact force (CF) at lesions adjacent to the RPV carina. Receiver operating characteristic (ROC) curve analysis identified CF < 10.5 g as a predictor of RPV CB, with 75.7% sensitivity and 56.2% specificity (area under the curve: 0.714). CONCLUSION: In patients undergoing AI-guided PVI with HPSD, lower CF adjacent to the carina was associated with a higher risk of RPV CB. These findings suggest that maintaining higher CF during ablation in this region may reduce the occurrence of RPV CB.

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.

Insight of electrocardiographic and electrophysiological parameters on the left ventricular function in patients with ventricular arrhythmia from left ventricular summit.

INTRODUCTION: Ventricular arrhythmia (VA) commonly originate from the left ventricular summit (LVS) and results in left ventricular (LV) dysfunction in some patients; however, factors related to LV cardiomyopathy have not been well elucidated. Therefore, this study aimed to investigate the risk factors for LV cardiomyopathy and the outcomes of patients with LVS VA. METHODS: Between 2013 and 2018, a total of 139 patients (60.7% men; mean age 53.2 ± 13.9 years old) underwent catheter ablation for LVS VA in two centers. Detailed patient demographics, electrocardiograms, electrophysiological characteristics, and clinical outcomes were analyzed. LV cardiomyopathy was defined as left ventricular ejection fraction (LVEF) <50%. RESULTS: Acute procedural success was achieved in 92.8% of patients. There were 40 patients (28.8%) with LV cardiomyopathy, and the mean LVEF improved from 37.5 ± 9.3% to 48.5 ± 10.2% after ablation (p < .001). After multivariate analysis, the independent factors of LV dysfunction were wider QRS duration (QRSd) of the VA (odds ratio [OR] 1.02; 95% confidence interval [CI]: 1.00-1.04; p = .046) and the absolute earliest activation time discrepancy (AEAD) between epicardium and endocardium (OR 1.05; 95% CI: 1.00-1.09; p = .048). After ablation, the LV function was completely recovered in 20 patients (50%). The factors for LV dysfunction without recovery included wider premature ventricular complex (PVC) QRSd (OR 1.09; 95% CI: 1.02-1.17; p = .012) and poorer LVEF (OR 0.85; 95% CI: 0.74-0.97; p = .020). CONCLUSION: In patients with VA from the LVS, PVC QRSd and AEAD are factors associated with deteriorating LV systolic function. Catheter ablation can reverse LV remodeling. Narrower QRSd and better LVEF are associated with better recovery of LV function after ablation.

Factors predicting the progression from paroxysmal to persistent atrial fibrillation despite an index catheter ablation.

INTRODUCTION: Despite undergoing an index ablation, some patients progress from paroxysmal atrial fibrillation (PAF) to persistent AF (PersAF), and the mechanism behind this is unclear. The aim of this study was to investigate the predictors of progression to PersAF after catheter ablation in patients with PAF. METHODS: This study included 400 PAF patients who underwent an index ablation between 2015 and 2019. The patients were classified into three groups based on their outcomes: Group 1 (PAF to sinus rhythm, n = 226), Group 2 (PAF to PAF, n = 146), and Group 3 (PAF to PersAF, n = 28). Baseline and procedural characteristics were collected, and predictors for AF recurrence and progression were evaluated. RESULTS: The mean age of the patients was 58.4 ± 11.1 years, with 272 males. After 3 years of follow-up, 7% of the PAF cases recurred and progressed to PersAF despite undergoing an index catheter ablation. In the multivariable analysis, a larger left atrial (LA) diameter and the presence of non-pulmonary vein (PV) triggers during the index procedure independently predicted recurrence. Moreover, a larger LA diameter, the presence of non-PV triggers, and a history of thyroid disease independently predicted AF progression. CONCLUSION: The progression from PAF to PersAF after catheter ablation is associated with a larger LA diameter, history of thyroid disease, and the presence of non-PV triggers. Meticulous preprocedural evaluation, patient selection, and comprehensive provocation tests during catheter ablation are recommended.

Comparison of Long-Term Clinical Outcomes Between Segmental and Circumferential Pulmonary Vein Isolation in Patients Undergoing Repeat Atrial Fibrillation Ablation.

BACKGROUND: Circumferential pulmonary vein isolation (CPVI) has supplanted segmental PVI (SPVI) as standard procedure for atrial fibrillation (AF). However, there is limited evidence examining the efficacy of these strategies in redo ablations. In this study, we investigated the difference in recurrence rates between SPVI and CPVI in redo ablations for PV reconnection.Methods and Results: This study retrospectively enrolled 543 patients who had undergone AF ablation between 2015 and 2017. Among them, 167 patients (30.8%, including 128 male patients and 100 patients with paroxysmal AF) underwent redo ablation for recurrent AF. Excluding 26 patients without PV reconnection, 141 patients [90 patients of SPVI (Group 1) and 51 patients of CPVI (Group 2)] were included. The AF-free survival rates were 53.3% and 56.9% in Group 1 and Group 2, respectively (P=0.700). The atrial flutter (AFL)-free survival rates were 90% and 100% in Group 1 and Group 2, respectively (P=0.036). The ablation time was similar between groups, and there no major complications were observed. CONCLUSIONS: For redo AF ablation procedures, SPVI and CPVI showed similar outcomes, except for a higher AFL recurrence rate for SPVI after long-term follow-up (>2 years). This may be due to a higher probability of residual PV gaps causing reentrant AFL.

The Role of Open Cardiopulmonary Resuscitation in Chest Trauma Patients with No Sign of Life: A National Trauma Data Bank Study.

PURPOSE: The effectiveness of open cardiopulmonary resuscitation (OCPR) remains controversial for trauma patients. In this current study, the role of OCPR in managing chest trauma patients is evaluated using nationwide real-world data. METHODS: From 2014 to 2015, the National Trauma Data Bank was retrospectively queried for chest trauma patients with out-of-hospital cardiac arrest status. The emergency department (ED) and overall survival of patients without signs of life were analyzed. Multivariate logistic regression (MLR) analysis was performed to evaluate independent factors of mortality for the target group. Furthermore, a subset group of patients who survived after the ED were studied, focusing on the duration of survival after leaving the ED. RESULTS: A total of 911 patients were enrolled in this study (OCPR vs. non-OCPR: 161 patients vs. 750 patients). The average overall mortality rate was 98.6% (N = 898). Among penetrating chest trauma patients, non-survivors in the ED had significantly higher proportions of gunshot injuries (83.9% vs. 69.7%, p = 0.001) and lower proportions of OCPR (20.7% vs. 44.4%, p < 0.001). MLR analysis showed that gunshot injuries and non-OCPR were significantly related to ED mortality in penetrating trauma patients without signs of life (odds ratio = 2.039, p = 0.006 and odds ratio = 2.900, p < 0.001, respectively). However, the overall survival rate of patients after ED survival (n = 99) was 9.9%, and only 21.2% (n = 21) of them survived more than 1 day after leaving the ED. CONCLUSION: OCPR could be considered in situations where appropriate indications exist. The survival benefit was observed in critically ill patients with penetrating chest trauma who show no signs of life. By enhancing ED survival, OCPR may also contribute to overall survival improvement.

Shared decision making for anticoagulation reduces anxiety and improves adherence in patients with atrial fibrillation.

BACKGROUND: Treatment with oral anticoagulants (OACs) could prevent stroke in atrial fibrillation (AF), but side effects developed due to OACs may cause patients anxiety during decision making. This study aimed to investigate whether shared decision making (SDM) reduces anxiety and improves adherence to stroke prevention measures in patients with AF. METHODS: A one-group pretest-posttest design using a questionnaire survey was applied at the outpatient cardiology clinic between July 2019 until September 2020. A Patient Decision Aid (PDA) tool was used for the completion of the questionnaire survey after health education and counseling. Ten questions were included for patients' recognition of SDM, and a 5-point scoring method was used, where "very much" was scored as 5 points, and "totally not" was scored as 1 point. RESULTS: Fifty-two patients with AF were enrolled. In terms of patients' recognition of SDM, points of more than 4.17 out of 5 were noted, indicating recognition above the level of "very much." The patients' anxiety scores before SDM were 3.56 (1.2), with a decrease of 0.64 points (p < 0.001) to 2.92 (1.3) after SDM. After SDM, the number of patients who decided to take OAC increased from 76.9% to 88.5%, and the 15.4% answering "unclear" decreased to 1.9% (p = 0.006). The patients' anxiety levels after SDM were associated with gender (p = 0.025). CONCLUSIONS: The approach using SDM enhanced our understanding of the pros and cons of OAC treatment and, in patients with AF, decreased anxiety about therapeutic decisions and increased willingness to accept treatment options.

Application of Ensite™ LiveView function for identification of scar-related ventricular tachycardia isthmus.

INTRODUCTION: Dynamic display of real-time wavefront activation pattern may facilitate the recognition of reentrant circuits, particularly the diastolic path of ventricular tachycardia (VT). OBJECTIVE: We aimed to evaluate the feasibility of LiveView Dynamic Display for mapping the critical isthmus of scar-related reentrant VT. METHODS: Patients with mappable scar-related reentrant VT were selected. The characteristics of the underlying substrates and VT circuits were assessed using HD grid multielectrode catheter. The VT isthmuses were identified based on the activation map, entrainment, and ablation results. The accuracy of the LiveView findings in detecting potential VT isthmus was assessed. RESULTS: We studied 18 scar-related reentrant VTs in 10 patients (median age: 59.5 years, 100% male) including 6 and 4 patients with ischemic and nonischemic cardiomyopathy, respectively. The median VT cycle length was 426 ms (interquartile range: 386-466 ms). Among 590 regional mapping displays, 92.0% of the VT isthmus sites were identified by LiveView Dynamic Display. The accuracy of LiveView for isthmus identification was 84%, with positive and negative predictive values of 54.8% and 97.8%, respectively. The area with abnormal electrograms was negatively correlated with the accuracy of LiveView Dynamic Display (r = -.506, p = .027). The median time interval to identify a VT isthmus using LiveView was significantly shorter than that using conventional activation maps (50.5 [29.8-120] vs. 219 [157.5-400.8] s, p = .015). CONCLUSION: This study demonstrated the feasibility of LiveView Dynamic Display in identifying the critical isthmus of scar-related VT with modest accuracy.

Does Thoracic Endovascular Aortic Repair for Blunt Thoracic Aortic Injury Increase the Probability of Delayed Intra-abdominal Hemorrhage in Patients With Concomitant Blunt Abdominal Trauma?

PURPOSE: Most blunt thoracic aortic injuries (BTAIs) may be treated using thoracic endovascular aortic repair (TEVAR), and most blunt abdominal traumas (BATs) are managed conservatively. We hypothesized that severe trauma that needs TEVAR may increase the risk of delayed intra-abdominal hemorrhage in patients with concomitant BTAI and BAT because of the potential hemorrhagic shock, disseminated intravascular coagulopathy, blood loss, consequent need for blood transfusion, and procedure-associated heparinization. MATERIALS AND METHODS: From 2015 to 2019, blunt trauma patients with concomitant severe chest trauma and abdominal trauma who could be managed conservatively were studied. The probability of delayed intra-abdominal hemorrhage was compared between patients with concomitant BTAI who received or did not undergo TEVAR. Propensity score matching (PSM), inverse probability of treatment weighting (IPTW), and multivariate logistic regression (MLR) were used to eliminate discrepancies between these 2 groups. RESULTS: Among the 341 studied patients, there were 26 patients with BTAI, and 19 of them underwent TEVAR. Delayed intra-abdominal hemorrhage was observed in 4 patients (21.1%, 4/19) who underwent TEVAR. Both PSM and IPTW showed that patients who underwent TEVAR for concomitant BTAI had a greater delayed need for blood transfusions and a larger proportion of delayed intra-abdominal hemorrhage than patients who did not undergo the procedure. The MLR analysis showed that TEVAR for BTAI was an independent risk factor for delayed intra-abdominal hemorrhage (odds ratio: 10.534, 95%, p<0.001). CONCLUSION: An increased probability of delayed intra-abdominal hemorrhage in patients with BAT (who could be managed conservatively) was observed in patients who underwent TEVAR for concomitant BTAI. CLINICAL IMPACT: More attention should be give in patients with high grade aortic injuries and concomitant abdominal trauma.

Long-term mortality and cardiovascular outcomes in patients with atrial flutter after catheter ablation.

AIMS: For patients with typical and atypical atrial flutter (AFL) but without history of atrial fibrillation (AF), the long-term cardiovascular (CV) outcomes after catheter ablation for AFL remain unclear. We compared the long-term all-cause mortality and CV outcomes in patients with AFL receiving catheter ablation compared with the results with medical therapy. METHODS AND RESULTS: Atrial flutter patients receiving catheter ablation for typical AFL were identified using the Health Insurance Database, and constituted the 'AFL ablation group'. Patients with typical and atypical AFL but without ablation (AFL without ablation group) were propensity matched to the AFL ablation group. Patients with prior AF diagnosis were excluded. Primary outcomes included all-cause and CV mortality, heart failure (HF) hospitalization, and stroke. The multivariable cox hazards regression model was used to evaluate the hazard ratio (HR) for study outcomes. A total of 3784 AFL patients (1892 patients in each group) was studied. Their mean follow-up durations were 7.85 ± 2.57 years (AFL without ablation group) and 8.31 ± 4.53 years (AFL ablation group). Atrial flutter with ablation patients had lower risks of all-cause mortality (HR: 0.68, P < 0.001), CV deaths (HR: 0.78, P = 0.001), HF hospitalization (HR: 0.84, P = 0.01), and stroke (HR: 0.80, P = 0.01). CONCLUSIONS: Catheter ablation for AFL in patients without prior AF was associated with lower risks of all-cause mortality and CV events compared with AFL patients without ablation during long-term follow-ups.

Non-vitamin K antagonist oral anticoagulants in atrial fibrillation patients with advanced chronic kidney and liver diseases.

Advanced chronic kidney disease (CKD) or chronic liver disease (CLD) is frequent in patients with atrial fibrillation (AF) because of their common risk factors. Chronic kidney disease and CLD superimposed on AF are associated with increased risks of thrombosis and bleeding, which further complicates the use of oral anticoagulants (OACs). Because currently approved non-vitamin K antagonist oral anticoagulants (NOACs) undergo certain degrees of metabolism and clearance in the liver and kidney, increased exposure to medications and risk of bleeding are major concerns with the use of NOACs in patients with advanced CKD and CLD. Besides, these patients were mostly excluded from landmark trials of NOACs and related cohort studies are also limited. Therefore, the optimal strategy for the use of NOACs in this population remains unclear. This review would go through current evidence regarding the safety and efficacy of NOACs in AF patients with advanced CKD and CLD and provide a comprehensive discussion for clinical practices.

The role of acute care surgeons in treating rib fractures-a retrospective cohort study from a single level I trauma center.

BACKGROUND: Rib fractures are the most common thoracic injury in patients who sustained blunt trauma, and potentially life-threatening associated injuries are prevalent. Multi-disciplinary work-up is crucial to achieving a comprehensive understanding of these patients. The present study demonstrated the experience of an acute care surgery (ACS) model for rib fracture management from a single level I trauma center over 13 years. METHODS: Data from patients diagnosed with acute rib fractures from January 2008 to December 2020 were collected from the trauma registry of Chang Gung Memorial Hospital (CGMH). Information, including patient age, sex, injury mechanism, Abbreviated Injury Scale (AIS) in different anatomic regions, injury severity score (ISS), index admission department, intensive care unit (ICU) length of stay (LOS), total admission LOS, mortality, and other characteristics of multiple rib fracture, were analyzed. Patients who received surgical stabilization of rib fractures (SSRF) were analyzed separately, and basic demographics and clinical outcomes were compared between acute care and thoracic surgeons. RESULTS: A total of 5103 patients diagnosed with acute rib fracture were admitted via the emergency department (ED) of CGMH in the 13-year study period. The Department of Trauma and Emergency Surgery (TR) received the most patients (70.8%), and the Department of Cardiovascular and Thoracic Surgery (CTS) received only 3.1% of the total patients. SSRF was initiated in 2017, and TR performed fixation for 141 patients, while CTS operated for 16 patients. The basic demographics were similar between the two groups, and no significant differences were noted in the outcomes, including LOS, LCU LOS, length of indwelling chest tube, or complications. There was only one mortality in all SSRF patients, and the patient was from the CTS group. CONCLUSIONS: Acute care surgeons provided good-quality care to rib fracture patients, whether SSRF or non-SSRF. Acute care surgeons also safely performed SSRF. Therefore, we propose that the ACS model may be an option for rib fracture management, depending on the deployment of staff in each institute.

Positive signs on physical examination are not always indications for endotracheal tube intubation in patients with facial burn.

BACKGROUND: After clinical evaluation in the emergency department (ED), facial burn patients are usually intubated to protect their airways. However, the possibility of unnecessary intubation or delayed intubation after admission exists. Objective criteria for the evaluation of inhalation injury and the need for airway protection in facial burn patients are needed. METHODS: Facial burn patients between January 2013 and May 2016 were reviewed. Patients who were and were not intubated in the ED were compared. All the intubated patients received routine bronchoscopy and laboratory tests to evaluate whether they had inhalation injuries. The patients with and without confirmed inhalation injuries were compared. Multivariate logistic regression analysis was used to identify the independent risk factors for inhalation injuries in the facial burn patients. The reasons for intubation in the patients without inhalation injuries were also investigated. RESULTS: During the study period, 121 patients were intubated in the ED among a total of 335 facial burn patients. Only 73 (60.3%) patients were later confirmed to have inhalation injuries on bronchoscopy. The comparison between the patients with and without inhalation injuries showed that shortness of breath (odds ratio = 3.376, p = 0.027) and high total body surface area (TBSA) (odds ratio = 1.038, p = 0.001) were independent risk factors for inhalation injury. Other physical signs (e.g., hoarseness, burned nostril hair, etc.), laboratory examinations and chest X-ray findings were not predictive of inhalation injury in facial burn patients. All the patients with a TBSA over 60% were intubated in the ED even if they did not have inhalation injuries. CONCLUSIONS: In the management of facial burn patients, positive signs on conventional physical examinations may not always be predictive of inhalation injury and the need for endotracheal tube intubation in the ED. More attention should be given to facial burn patients with shortness of breath and a high TBSA. Airway protection is needed in facial burn patients without inhalation injuries because of their associated injuries and treatments.

Risks of Ventricular Tachyarrhythmia and Mortality in Patients with Amyloidosis - A Long-Term Cohort Study.

Background: The presence of ventricular tachycardia (VT) is associated with higher mortality. The annual incidence of VT after a diagnosis of amyloidosis and the associated cardiovascular (CV) outcomes have not been well assessed in a large cohort. Methods: A total of 12,139 amyloidosis patients were identified from the Taiwan National Health Insurance Research Database. Non-amyloidosis group was matched 1:1 for age, gender, hypertension, and diabetes mellitus (DM) to the amyloidosis group using a propensity score. Analysis of the risk of CV outcomes was conducted. We also analyzed the incidence of cardiac amyloidosis (CA). Results: The incidence rates of amyloidosis and CA were 6.54 and 0.61 per 100,000 person-years, respectively. Multivariable analysis revealed that the risk of VT was higher in both the amyloidosis [hazard ratio (HR): 7.90; 95% confidence interval (CI): 4.49-13.9] and CA (HR: 153.3, 95% CI: 54.3-432.7) groups. In the amyloidosis group, the risk of heart failure (HF)-related hospitalization, CV death, and all-cause death was also higher. Amyloidosis was associated with a higher CV mortality rate following VT (HR: 1.50; 95% CI: 1.07-2.12). The onset of a new VT event in patients with amyloidosis was associated with HF, DM, chronic liver disease, and anti-arrhythmic drug use. Conclusions: In this nationwide cohort study, the incidence rates of amyloidosis and CA were 6.54 and 0.61 per 100,000 person-years, respectively. The long-term risks of VT and CV mortality were higher in the patients with amyloidosis and CA. The patients with amyloidosis had a poorer prognosis following VT events, highlighting the importance of continuous monitoring in these patients.

Esophageal luminal temperature rise during atrial fibrillation ablation is associated with lower radiofrequency electrode distance and baseline impedance.

INTRODUCTION: Esophageal injury during atrial fibrillation (AF) ablation is a life-threatening complication. We sought to measure the association of esophageal temperature attenuation with radiofrequency (RF) electrode impedance, contact force, and distance from the esophagus. METHODS: The retrospective study cohort included 35 patients with mean age 64 ± 10 years, of whom 74.3% were male, and 40% had persistent AF. All patients had undergone preprocedural cardiac magnetic resonance (CMR) followed by AF ablation with luminal esophageal temperature monitoring. Lesion locations were co-registered with CMR image segmentations of left atrial and esophageal anatomy. Luminal esophageal temperature, time matched RF lesion data, and ablation distance from the nearest esophageal location were collected as panel data. RESULTS: Luminal esophageal temperature changes corresponding to 3667 distinct lesions, delivered with mean power 27.9 ± 5.5 W over a mean duration of 22.2 ± 10.5 s were analyzed. In multivariable analyses, clustered per patient, examining posterior wall lesions only, and adjusted for lesion power and duration as set by the operator, lesion distance from the esophagus (-0.003°C/mm, p < .001), and baseline impedance (-0.015°C/Ω, p < .001) were associated with changes in luminal esophageal temperature. CONCLUSION: Esophageal luminal temperature rises are associated with shorter lesion distance from esophagus and lower baseline impedance during RF lesion delivery. When procedural strategy requires RF delivery near the esophagus, selection of sites with higher baseline impedance may improve safety.

Arrhythmogenic right ventricular cardiomyopathy: diverse substrate characteristics and ablation outcome.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy caused by defective desmosomal proteins. The typical histopathological finding of ARVC is characterized by progressive fibrofatty infiltration of the right ventricle due to the dysfunction of cellular adhesion molecules, thus, developing arrhythmogenic substrates responsible for the clinical manifestation of ventricular tachycardia/fibrillation (VT/VF). Current guidelines recommend implantable cardiac defibrillator (ICD) implantation to prevent sudden cardiac death (SCD) in ARVC, especially for those experiencing VT/VF or aborted SCD, while antiarrhythmic drugs, despite their modest effectiveness and several undesirable adverse effects, are frequently used for those experiencing episodes of ICD interventions. Given the advances in mapping and ablation technologies, catheter ablation has been implemented to eliminate drug-refractory VT in ARVC. A better understanding of the pathogenesis, underlying arrhythmogenic substrates, and putative VT isthmus in ARVC contributes to a significant improvement in ablation outcomes through comprehensive endocardial and epicardial approaches. Regardless of ablation strategies, there is a diversity of arrhythmogenic substrates in ARVC, which could partly explain the nonuniform ablation outcome and long-term recurrences and reflect the role of potential factors in the modification of disease progression and triggering of arrhythmic events.

Clinical significance of J waves with respect to substrate characteristics and ablation outcomes in patients with arrhythmogenic right ventricular cardiomyopathy.

AIMS: J-wave syndrome in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) has been linked to an increased risk of ventricular arrhythmia. We investigated the significance of J waves with respect to substrate manifestations and ablation outcomes in patients with ARVC. METHODS AND RESULTS: Forty-five patients with ARVC undergoing endocardial/epicardial mapping/ablation were studied. Patients were classified into two groups: 13 (28.9%) and 32 (71.1%) patients with and without J waves, respectively. The baseline characteristics, electrophysiological features, ventricular substrate, and recurrent ventricular tachycardia/fibrillation (VT/VF) were compared. Among the 13 patients with J waves, only the inferior J wave was observed. More ARVC patients with J waves fulfilled the major criteria of ventricular arrhythmias (76.9% vs. 21.9%, P = 0.003). Similar endocardial and epicardial substrate characteristics were observed between the two groups. However, patients with J waves had longer epicardial total activation time than those without (224.7 ± 29.9 vs. 200.8 ± 21.9 ms, P = 0.005). Concordance of latest endo/epicardial activation sites was observed in 29 (90.6%) patients without J waves and in none among those with J waves (P < 0.001). Complete elimination of endocardial/epicardial abnormal potentials resulted in the disappearance of the J wave in 8 of 13 (61.5%) patients. The VT/VF recurrences were not different between ARVC patients with and without J waves. CONCLUSION: The presence of J waves was associated with the discordance of endocardial/epicardial activation pattern in terms of transmural depolarization discrepancy in patients with ARVC.

Optimal Management of Anticoagulation Therapy in Asian Patients With Atrial Fibrillation.

Stroke prevention is the cornerstone of management of atrial fibrillation (AF), and non-vitamin K antagonist oral anticoagulants (NOACs) are commonly prescribed. Because routine monitoring of anticoagulant effects of NOACs is not necessary, appropriate dosing following the criteria of each NOACs defined in pivotal randomized trials is important. Real-world data demonstrate that underdosing NOACs is associated with a higher risk of ischemic stroke without a lower risk of major bleeding. Furthermore, renal function of AF patients should be assessed using the Cockcroft-Gault formula to prevent overestimation that could result in overdosing of NOACs. The assessment of bleeding risk is important, and the HAS-BLED score should be used to help identify patients at high risk of bleeding (HAS-BLED score ≥3). Moreover, the HAS-BLED score should be reassessed at periodic intervals to address potentially modifiable bleeding risk factors because bleeding risks of AF patients are not static. When managing NOAC-related bleeding episodes, the possibility of occult malignancies (e.g., grastrointestinal [GI] tract cancers for patients experiencing GI bleeding and bladder cancer for patients with hematuria) should be kept in mind. Addressing all of these issues is crucial to achieving better clinical outcomes for anticoagulated AF patients. More efforts are necessary to incorporate clear and easy-to-follow recommendations about optimal management of anticoagulation into the guidelines to improve AF patient care.

Distribution of triggers foci and outcomes of catheter ablation in atrial fibrillation patients in different age groups.

BACKGROUND: Atrial fibrillation (AF) prevalence increases with age. Aging affects the substrate properties of the left atrium (LA) and the outcomes of catheter ablation for treating AF. We investigated the AF trigger distribution and catheter ablation outcomes in patients of different ages with AF. METHODS: 1585 patients with AF (1181 paroxysmal and 404 non- paroxysmal AF) who had undergone catheter ablation were enrolled. The patients were divided into young (20-40 year-old, n = 175), middle-aged (41-64 year-old, n = 1134), and old (≥ 65 year-old, n = 276) groups. Electrophysiological characteristics and AF trigger sites were recorded. RESULT: The incidence of AF with only non-pulmonary vein (non-PV) foci was higher in the young group than in the other groups (8.6% vs. 3.6% vs. 3.3%, p < 0.01). Non-PV foci were more commonly located in the superior vena cava (SVC) in the young group than in the other groups (13.1% vs. 7.8% vs. 6.5%, p = 0.03). The left atrium (LA) mean voltage was higher and the incidence of very late recurrence after AF ablation was lower in the young group than in the other groups. However, the final AF recurrence rate after multiple procedures and complication rates were similar among all the groups at a mean follow-up of 5.6 years. CONCLUSION: The young patients with AF had a higher incidence of only non-PV foci, mostly located in SVC, than the middle-aged and old patients. Our study highlights the importance of identifying the non-PV foci in catheter ablation of young patients with AF.

Case series on stereotactic body radiation therapy in non-ischemic cardiomyopathy patients with recurrent ventricular tachycardia.

INTRODUCTION: The efficacy of stereotactic body radiation therapy (SBRT) as an alternative treatment for recurrent ventricular tachycardia (VT) is still unclear. This study aimed to report the outcome of SBRT in VT patients with nonischemic cardiomyopathy (NICM). METHODS: The determination of the target substrate for radiation was based on the combination of CMR results and electroanatomical mapping merged with the real-time CT scan image. Radiation therapy was performed by Flattening-filter-free (Truebeam) system, and afterward, patients were followed up for 13.5 ± 2.8 months. We analyzed the outcome of death, incidence of recurrent VT, ICD shocks, anti-tachycardia pacing (ATP) sequences, and possible irradiation side-effects. RESULTS: A total of three cases of NICM patients with anteroseptal scar detected by CMR. SBRT was successfully performed in all patients. During the follow-up, we found that VT recurrences occurred in all patients. In one patient, it happened during a 6-week blanking period, while the others happened afterward. Re-hospitalization due to VT only appeared in one patient. Through ICD interrogation, we found that all patients have reduced VT burden and ATP therapies. All of the patients died during the follow-up period. Radiotherapy-related adverse events did not occur in all patients. CONCLUSIONS: SBRT therapy reduces the number of VT burden and ATP sequence therapy in NICM patients with VT, which had a failed previous catheter ablation. However, the efficacy and safety aspects, especially in NICM cases, remained unclear.