Evaluation of ventricular pacing suppression algorithms in dual chamber pacemaker: Results of "LEADER" study.

Background: There is limited research on the intra-individual efficacy of ventricular pacing minimization algorithms developed by Biotronik-the Ventricular Pace Suppression algorithm (VpS) and the Intrinsic Rhythm Support plus algorithm (IRSplus) (BIOTRONIK SE & Co. KG, Berlin, Germany). We performed a randomized pilot trial that evaluated the efficacy of two algorithms in patients with symptomatic sinus node dysfunction (SND) who received a dual-chamber pacemaker. Methods: The trial was conducted in 11 tertiary hospitals in South Korea. The patients were randomized to either the VpS or IRSplus algorithm group after a 3-month period of fixed atrioventricular (AV) delay. The primary outcome was the ventricular pacing percentage (Vp%) at each follow-up visit. The secondary outcomes were the occurrence of heart failure (HF) and atrial fibrillation (AF) during the study period. Results: Data from 131 patients were analyzed. Initially, their average Vp% over 3 months with a fixed AV interval was 14.1 ± 19.4%. Patients were randomly assigned to VpS and IRSplus groups, with 66 and 65 in each. Algorithms reduced average Vp% to 4.0 ± 11.3% at 9 months and 6.7 ± 14.9% at 15 months. These algorithms were more effective for patients with paced AV delay (PAVD) ≤300 ms compared to those with PAVD >300 ms. Both algorithms were equally effective in reducing Vp%. Clinical AF or HF hospitalization was not observed during the study period. Conclusion: The VpS and IRSplus algorithms are effective and safe in minimizing unnecessary ventricular pacing in patients with SND.

Clinical characteristics of apixaban prescription in AF patients with single dose-reduction criterion: the ASPIRE (efficAcy and safety of aPixaban in rEal-world practice in Korean frail patients with atrial fibrillation) study.

Background: Data on off-label reduced dose risk among patients with atrial fibrillation (AF) who qualify for a single-dose reduction of apixaban is scarce. Objectives: We prospectively assessed apixaban dosing and clinical characteristics in AF patients meeting a dose reduction criterion. Methods: The multicentre, prospective cohort study, the efficAcy and Safety of aPixaban In REal-world practice in Korean frail patients with AF (ASPIRE), encompasses patients with AF who met the criteria for a single-dose reduction of apixaban and were given varying doses of apixaban, either the on-label standard dose or the off-label reduced dose. Results: Of 2,000 patients (mean age 74.3 ± 7.9 years, 55.8% women), 29.7% were ≥80 years, 62.6% weighed ≤60 kg, and 7.8% had serum creatinine ≥1.5 mg/dL. Of these, 51.3% were prescribed an off-label reduced dose of apixaban. The off-label group was characterized with older age, more comorbidities, and antiplatelet agents, while the on-label group had more prior strokes. Physicians preferred off-label reduced dose in the "marginal zone," defined as age 75-80 years, weight 60-65 kg, and creatinine levels 1.2-1.5 mg/dL. Conclusions: In real-world clinical setting of the Korean population, off-label reduced dose apixaban was administered to nearly half of the patients who qualified for a single dose reduction. This reduced dosage was more commonly prescribed to patients with frail characteristics, while patients with a history of stroke were more often given the standard dose as per the label. A future study is planned to contrast the safety and effectiveness of the standard dose against the reduced dose of apixaban in this population.

Autonomic Modulation of Atrial Fibrillation.

The autonomic nervous system plays a vital role in cardiac arrhythmias, including atrial fibrillation (AF). Therefore, reducing the sympathetic tone via neuromodulation methods may be helpful in AF control. Myocardial ischemia is associated with increased sympathetic tone and incidence of AF. It is an excellent disease model to understand the neural mechanisms of AF and the effects of neuromodulation. This review summarizes the relationship between autonomic nervous system and AF and reviews methods and mechanisms of neuromodulation. This review proposes that noninvasive or minimally invasive neuromodulation methods will be most useful in the future management of AF.

Comparing the Efficacy of Carvedilol and Flecainide on the Treatment of Idiopathic Premature Ventricular Complexes from Ventricular Outflow Tract: A Multicenter, Randomized, Open-Label Pilot Study.

The mechanism of premature ventricular complexes (PVC) occurring in the ventricular outflow tract (OT) is related to an intracellular calcium overload and delayed afterdepolarizations that lead to triggered activity. The guidelines recommend using beta-blockers and flecainide for idiopathic PVCs, but they also acknowledge the limited evidence supporting this recommendation. We conducted a multicenter, randomized, open-label pilot study comparing the effect of carvedilol and flecainide on OT PVC, which are widely used to treat this arrhythmia. Patients with a 24 h Holter recording a PVC burden ≥ 5%, which showed positive R waves in leads II, III, and aVF, and without structural heart disease were enrolled. They were randomly assigned to the carvedilol or flecainide group, and the maximum tolerated dose was administered for 12 weeks. A total of 103 participants completed the protocol: 51 with carvedilol and 52 with flecainide. After 12 weeks of treatment, the mean PVC burden significantly decreased in both groups: 20.3 ± 11.5 to 14.6 ± 10.8% with carvedilol (p < 0.0001) and 17.1 ± 9.9 to 6.6 ± 9.9% with flecainide (p < 0.0001). Both carvedilol and flecainide effectively suppressed OT PVCs in patients without structural heart disease, with flecainide showing a superior efficacy compared to carvedilol.

The higher recurrence rate after catheter ablation in younger patients with atrial fibrillation suggesting different pathophysiology.

BACKGROUND: Young atrial fibrillation (AF) patients have been underrepresented in studies of radiofrequency catheter ablation (RFCA) and the outcome of RFCA has not been widely addressed. We investigated age-related differences in clinical features, the recurrence of atrial tachyarrhythmia, and its predictors of patients who underwent RFCA for AF. METHODS: This is a multicenter prospective study of 2799 patients who underwent RFCA for AF in 2017-2020. The patients were divided into two groups - group A (age < 60 years, n = 1269) and group B (age ≥ 60 years, n = 1530) - and a recurrence of any atrial tachyarrhythmia 1 year after RFCA following a 90-day blanking period was compared. RESULTS: The mean age was 51.6 ± 6.7 and 66.8 ± 5.2 years for groups A and B, respectively. Higher body mass index, smaller left atrium, and more prevalent cardiomyopathy and obstructive sleep apnea were observed in group A. Overall, 1-year atrial tachyarrhythmia-free survival was 85.6% and lower in young patients (83.1% in group A vs. 87.7% in group B, log-rank p < 0.01): adjusted hazard ratio (aHR) of recurrence (95% confidence interval (CI)), 1.45 (1.13-1.86) for group A compared to group B (p < 0.01). The association between younger age and higher recurrence was continuously observed in patients under 60 years. Any non-PV ablation was associated with a lower recurrence of atrial tachyarrhythmia in group B (aHR 0.68 (0.47-0.96), p < 0.05), but not in group A. CONCLUSIONS: AF patients younger than 60 years had a higher 1-year AF recurrence after RFCA. Young AF patients might have distinctive pathophysiology of AF requiring more integrated management.

Effect of Atorvastatin on Serial Changes in Coronary Physiology and Plaque Parameters.

Background: The effects of statin on coronary physiology have not been well evaluated. Objectives: The authors performed this prospective study to investigate changes in coronary flow indexes and plaque parameters, and their associations with atorvastatin therapy in patients with coronary artery disease (CAD). Methods: Ninety-five patients with intermediate CAD who received atorvastatin therapy underwent comprehensive physiological assessments with fractional flow reserve (FFR), coronary flow reserve, index of microcirculatory resistance, and intravascular ultrasound at the index procedure, and underwent the same evaluations at 12-month follow-up. Optimal low-density lipoprotein cholesterol (LDL-C) was defined as LDL-C <70 mg/dL or ≥50% reduction from the baseline. The primary endpoint was a change in the FFR. Results: Baseline FFR, minimal lumen area, and percent atheroma volume (PAV) were 0.88 ± 0.05, 3.87 ± 1.28, 55.92 ± 7.30, respectively. During 12 months, the percent change in LDL-C was -33.2%, whereas FFR was unchanged (0.87 ± 0.06 at 12 months; P = 0.694). Vessel area, lumen area, and PAV were significantly decreased (all P values <0.05). The achieved LDL-C level and the change of PAV showed significant inverse correlations with the change in FFR. In patients with optimally modified LDL-C, the FFR had increased (0.87 ± 0.06 vs 0.89 ± 0.07; P = 0.014) and the PAV decreased (56.81 ± 6.44% vs 55.18 ± 8.19%; P = 0.031), whereas in all other patients, the FFR had decreased (0.88 ± 0.05 vs 0.86 ± 0.06; P = 0.025) and the PAV remained unchanged. Conclusions: In patients with CAD, atorvastatin did not change FFR despite a decrease in the PAV. However, in patients who achieved the optimal LDL-C target level with atorvastatin, the FFR had significantly increased with decrease of the PAV. (Effect of Atorvastatin on Fractional Flow Reserve in Coronary Artery Disease [FORTE]; NCT01946815).

Prevalence and Characteristics of Atrial Tachycardia From Noncoronary Aortic Cusp During Atrial Fibrillation Catheter Ablation.

BACKGROUND AND OBJECTIVES: Atrial tachycardias (ATs) from noncoronary aortic cusp (NCC) uncovered after radiofrequency ablation for atrial fibrillation (AF) are rarely reported. This study was conducted to investigate the prevalence and clinical characteristics of NCC ATs detected during AF ablation and compare their characteristics with de novo NCC ATs without AF. METHODS: Consecutive patients who underwent radiofrequency catheter ablation for AF were reviewed from the multicenter AF ablation registry of 11 tertiary hospitals. The clinical and electrophysiological characteristics of NCC AT newly detected during AF ablation were compared with its comparators (de novo NCC AT ablation cases without AF). RESULTS: Among 10,178 AF cases, including 1,301 redo ablation cases, 8 (0.08%) NCC AT cases were discovered after pulmonary vein isolation (PVI; 0.07% in first ablation and 0.15% in redo ablation cases). All ATs were reproducibly inducible spontaneously or with programmed atrial stimulation without isoproterenol infusion. The P-wave morphological features of tachycardia were variable depending on the case, and most cases exhibited 1:1 atrioventricular conduction. AF recurrence rate after PVI and NCC AT successful ablation was 12.5% (1 of 8). Tachycardia cycle length was shorter than that of 17 de novo ATs from NCC (303 versus 378, p=0.012). No AV block occurred during and after successful AT ablation. CONCLUSIONS: Uncommon NCC ATs (0.08% in AF ablation cases) uncovered after PVI, showing different characteristics compared to de-novo NCC ATs, should be suspected irrespective of P-wave morphologies when AT shows broad propagation from the anterior interatrial septum.

Drug Utilization Pattern of Oral Anticoagulants in Patients with Atrial Fibrillation: A Nationwide Population-Based Study in Korea.

INTRODUCTION: Treatment persistence for anticoagulant therapy is important in preventing thromboembolism in nonvalvular atrial fibrillation (NVAF) patients. Understanding drug utilization pattern and treatment changes in oral anticoagulant (OAC) users may facilite better NVAF management. Thus, our study aimed to examine OAC treatment patterns preceding events leading to switch or discontinuation and medication adherence in Korean NVAF patients. METHODS: We conducted a drug utilization study on all Korean patients with atrial fibrillation (AF) newly prescribed OACs between July 2015 and November 2016 using the national claims data. We assessed treatment changes such as switching and discontinuation from index OAC and relevant events preceding the change and examined patient characteristics as predictors of changes that occurred among OAC users. Medication adherence was compared among OAC users by calculating the medication possession ratio (MPR). RESULTS: A total of 48,389 NVAF patients were identified who initiated OACs within the study period. Most initiated nonvitamin K antagonist oral anticoagulants (NOACs) (22% apixaban, 24% dabigatran, 37% rivaroxaban), and 18% initiated warfarin. The frequency of switch to another OAC was 8.8% for apixaban, 16.1% for dabigatran, 6.6% for rivaroxaban, and 19.1% for warfarin. The frequency of discontinuation was lower for apixaban (22.9%), dabigatran (26.3%), and rivaroxaban (25.7%) than warfarin (31.6%). Compared to warfarin, NOAC users were less likely to switch treatment. Thromboembolic event was the most common clinical event preceding switch from warfarin to NOAC and from NOAC to warfarin. Discontinuation of OAC was often preceded by a bleeding event. Patients who initiated apixaban showed significantly higher mean MPR compared to those on dabigatran and warfarin. CONCLUSION: In real-world practice in Korea, we have observed treatment change to be common in OAC users. Our results indicate better medication adherence with NOACs than with warfarin. (ClinicalTrials.gov registration number NCT03572972).

Anticoagulants are drugs that thin blood with the purpose of preventing thromboembolic disease (e.g., stroke), which is a disease occurring when a blood clot forms or blocks vessel. Maintaining treatment for anticoagulation is important to prevent stroke in atrial fibrillation (AF) patients. To understand current drug usage pattern and treatment changes related to oral anticoagulants (OAC) we examined OAC treatment patterns and preceding events that led to drug switch or stop and medication maintenance by Korean AF patients.The study was conducted by utilizing the Korean national claims data from July 2015 to November 2016. All AF patients who newly started taking OAC were included in the analysis. In total, 48,389 patients were identified with most (83%) taking nonvitamin K antagonist oral anticoagulants (NOAC), which are newer generation blood thinners, including apixaban, dabigatran, and rivaroxaban, and 18% taking warfarin, the conventional blood thinner. Compared to warfarin, NOAC users were less likely to switch to other treatment. NOAC users discontinued the treatment less frequently than warfarin users. Thromboembolic events commonly preceded switch between OACs. Patients who stopped taking OACs were often confronted with a bleeding event before stopping treatment. Apixaban takers showed higher treatment persistence compared to dabigatran or warfarin users. In this study, we determined that treatment change is common in OAC-using patients. The results suggest that NOAC users may better adhere to treatment than warfarin users.

The benefits of the earlier use of sacubitril/valsartan in de novo heart failure with reduced ejection fraction patients.

AIMS: We evaluated the clinical outcomes and trajectory of cardiac reverse remodelling according to the timing of sacubitril/valsartan (Sac/Val) use in patients with heart failure (HF) with reduced ejection fraction (HFrEF). METHODS AND RESULTS: Patients with de novo HFrEF who used Sac/Val between June 2017 and October 2019 were retrospectively enrolled. Patients were grouped into the earlier use group (initiation of Sac/Val < 3 months after the first HFrEF diagnosis) and the later use group (initiation of Sac/Val ≥ 3 months after the first HFrEF diagnosis). Primary outcome was a composite of HF hospitalization and cardiac death. Secondary outcomes were HF hospitalization, cardiac death, all-cause death, significant ventricular arrhythmia (ventricular tachycardia or ventricular fibrillation), and echocardiographic evidence of cardiac reverse remodelling including left ventricular ejection fraction (LVEF) change during follow-up. Among 115 enrolled patients, 67 were classified in the earlier use group, and 48 were classified in the later use group. Mean period of HFrEF diagnosis to Sac/Val use was 52.1 ± 14.3 days in the earlier use group, and 201.8 ± 127.3 days in the later use group. During the median follow-up of 721 days, primary outcome occurred in 21 patients (18.3%). The earlier use group experienced significantly fewer primary outcome than the later use group (10.4% vs. 29.2%, P = 0.010). The Kaplan-Meier survival curve showed better event-free survival in the earlier use group than in the later use group (log rank = 0.017). There were no significant differences in cardiac death, all-cause death, and ventricular arrhythmia between two groups (1.5% vs. 2.1%, P = 0.811; 1.5% vs. 4.2%, P = 0.375; 3.0% vs. 0%, P = 0.227, respectively). Despite a significantly lower baseline LVEF in the earlier use group (21.3 ± 6.4% vs. 24.8 ± 7.9%, P = 0.012), an early prominent increase of LVEF was noted before 6 months (35.2 ± 11.9% vs. 27.8 ± 8.8%, P = 0.007). A delayed improvement of LVEF in the later use group resulted in similar LVEF at last follow-up in both groups (40.7 ± 13.4% vs. 39.4 ± 10.9%, P = 0.686). Although the trajectory of left ventricular remodelling showed similar pattern in two groups, left atrial (LA) reverse remodelling was less prominent in the later use group during the follow-up period (final LA volume index: 43.6 ± 14.3 mL/m2 vs. 55.2 ± 17.1 mL/m2 , P = 0.011). CONCLUSIONS: Earlier use of Sac/Val was related with better clinical outcome and earlier left ventricular reverse remodelling. Remodelling of LA was less prominent in the later use group implying delayed response in diastolic function.

Comorbidities and Antithrombotic Treatment Pattern in Patients With Atrial Fibrillation.

Objective: Non-vitamin K antagonist oral anticoagulants (NOACs) are proven alternatives to warfarin for preventing stroke in patients with non-valvular atrial fibrillation. We aimed to examine the treatment patterns and patient factors associated with the use of antiplatelet agents, warfarin, and NOACs in clinical practice. Methods: We conducted a retrospective cohort study using the Korean Health Insurance Review & Assessment Service database. Patients receiving antithrombotics were identified before and after the introduction of NOACs (from August 1, 2013 to December 30, 2014 and July 1, 2015 to November 30, 2016, respectively). Patients were included if they were aged ≥18 years, had an atrial fibrillation diagnosis, and had a CHA2DS2-VASc score ≥2. Treatment pattern was assessed by classifying patients into NOAC, warfarin, or antiplatelet users based on the first date of antithrombotic prescription. Clinical factors associated with the type of antithrombotics chosen were examined using logistic regression analyses. Results: We identified 129,465 and 196,243 patients before and after the introduction of NOACs, respectively. The proportion of antiplatelet users was 60.7 and 53.0% before and after the introduction of NOACs, respectively. The proportion of warfarin users was higher in patients with low HAS-BLED score, high CHA2DS2-VASc score, or stroke before the NOAC era. A similar trend was observed for NOAC and warfarin users after the introduction of NOAC. Compared with antiplatelets, warfarin and NOAC uses were significantly associated with CHA2DS2-VASc score and stroke, whereas presence of myocardial infarction (MI) and peripheral arterial disease were significantly associated with antiplatelets prescription. For comparisons between NOAC and warfarin, HAS-BLED and CHA2DS2-VASc scores showed significant associations with NOAC use, whereas comorbidities including MI were significantly associated with warfarin use. Conclusions: The treatment pattern of antithrombotics did not change with the introduction of NOACs. However, comorbidities served as an important factor in choosing treatment regardless of NOAC entry.

Surveillance of adenosine stress myocardial contrast echocardiography following percutaneous coronary intervention.

BACKGROUND: The ability of adenosine stress myocardial contrast echocardiography (AS-MCE) to reveal decreased coronary blood flow or perfusion defects (PDs) has not been explored for clinical implications after coronary revascularization. This study sought to identify the prognostic value of PDs in asymptomatic patients following percutaneous coronary intervention (PCI). METHODS: We retrospectively analyzed 342 asymptomatic patients (67 years of mean age, 72% male) who underwent PCI with stents at least 9 months before AS-MCE between May 2019 and December 2020. Resting regional wall motion abnormality (rRWMA) and the patterns of PDs were assessed, and further PDs were classified as ischemic or fixed type. The primary endpoint was the composite of hospitalization for worsening heart failure, coronary revascularization, and cardiac death. RESULTS: In AS-MCE (median time interval following PCI: 17.4 months), PDs were present in 93 (27.2%) out of 342 patients; 70 of ischemic PD (75.3%), 58 of fixed PD (62.4%). Those with PD showed a higher frequency of rRWMA than those without PD (53.8 vs. 15.7%, p < 0.001). During the median follow-up of 22.6 months, 26 (7.6%) patients experienced more associated clinical outcomes with PD than rRWMA. Cox analysis revealed that the combined findings of rRWMA and PD, and specifically, ischemic PD of ≥ 2 segments were associated with a high increase in adverse outcomes. CONCLUSIONS: AS-MCE provided prognostic value in asymptomatic patients with prior PCI. PD might be complementary to rRWMA in risk stratification.

Effectiveness and safety of non-vitamin K antagonist oral anticoagulants in patients with non-valvular atrial fibrillation: A nationwide, population-based study in Korea.

BACKGROUND: To compare the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) between non-vitamin K antagonist oral anticoagulants (NOACs) in patients with atrial fibrillation (AF), this retrospective study was conducted using the Korean Health Insurance Review & Assessment Service (HIRA) claims database. METHODS: Patients with AF who initiated NOACs (apixaban, dabigatran, and rivaroxaban) from July 1, 2015 to November 30, 2016 were included. We applied inverse probability of treatment weighting (IPTW) method using propensity score to make weighted populations having similar characteristics between groups. Hazard ratio (HR) of S/SE and MB were estimated by Cox proportional hazard model. RESULTS: Of the 39 783 patients with AF, 10 564; 11 418; and 17 801 used apixaban, dabigatran, and rivaroxaban, respectively. The mean CHA2DS2-VASc and HAS-BLED scores were 4.59 ~ 4.69 and 3.58 ~ 3.62, respectively, among all patients after applying IPTW. For S/SE, there were no significant differences between NOACs (HR [95% confidence interval (CI)]): apixaban vs dabigatran (0.99 [0.87-1.13]), apixaban vs rivaroxaban (0.95 [0.84-1.07]), and dabigatran vs rivaroxaban (0.96 [0.85-1.08]). For MB (HR [95% CI]), both apixaban (0.77 [0.68-0.86]) and dabigatran (0.88 [0.79-0.98]) had a significantly lower risk compared with rivaroxaban. Apixaban also had a significantly lower risk of MB compared with dabigatran (0.87 [0.76-0.99]). CONCLUSIONS: In real-world practice among Korean AF patients with relatively high risk of stroke and bleeding, there were no significant differences in the risk of S/SE between all NOAC comparisons. Apixaban was associated with lower risk of MB than dabigatran and rivaroxaban.

Electrocardiographic Manifestations in Patients with COVID-19: Daegu in South Korea.

BACKGROUND AND OBJECTIVES: As the coronavirus disease 2019 (COVID-19) spreads worldwide, cardiac injury in patients infected with COVID-19 becomes a significant concern. Thus, this study investigates the impact of several electrocardiogram (ECG) parameters and disease severity in COVID-19 patients. METHODS: Seven medical centers in Daegu admitted 822 patients with COVID-19 between February and April 2020. This study examined 267 patients among them who underwent an ECG test and evaluated their biochemical parameters like C-reactive protein (CRP), log N-terminal pro-B-type Natriuretic Peptide (NT-proBNP), cardiac enzyme, and ECG parameters (heart rate, PR interval, QRS interval, T inversion, QT interval, and Tpe [the interval between peak to end in a T wave]). RESULTS: Those patients were divided into 3 groups of mild (100 patients), moderate (89 patients), and severe (78 patients) according to clinical severity score. The level of CRP, log NT-proBNP, and creatinine kinase-myocardial band were significantly increased in severe patients. Meanwhile, severe patients exhibited prolonged QT intervals (QTc) and Tpe (Tpe-c) compared to mild or moderate patients. Moreover, deceased patients (58; 21.7%) showed increased dispersion of QTc and Tpe-c compared with surviving patients (78.2±41.1 vs. 40.8±24.6 ms and 60.2±37.3 vs. 40.8±24.5 ms, both p<0.05, respectively). The QTc dispersion of more than 56.1 ms could predict the mortality in multivariate analysis (odd ratio, 11.55; 95% confidence interval, 3.746-42.306). CONCLUSIONS: COVID-19 infections could involve cardiac injuries, especially cardiac repolarization abnormalities. A prolonged QTc dispersion could be an independent predictable factor of mortality.

Treatment Pattern of Antithrombotic Therapy over Time after Percutaneous Coronary Intervention in Patients with Atrial Fibrillation in Real-World Practice in Korea.

We examined antithrombotic treatment patterns with clinical characteristics and therapy changes over time in patients with atrial fibrillation (AF) after percutaneous coronary intervention (PCI). Using the Health Insurance Review and Assessment service claims database (01JAN2007-30NOV2016) in Korea, we included adult patients with AF and PCI: (1) who underwent PCI with stenting between 01JAN2008 and 30NOV2016; (2) with ≥1 claim for AF (ICD code: I48) (3) with antithrombotics 1 day prior to or at the date of PCI; and (4) with CHADS2-VASc of ≥2. In this study, 7749 patients with AF who underwent PCI, triple therapy, dual therapy, dual antiplatelet therapy (DAPT), and single antiplatelet therapy were prescribed to 24.6%, 3.4%, 60.8%, and 11.0%, respectively. In the triple therapy group, 23.1% persisted with triple therapy for 12 months, whereas the remaining patients switched to a different therapy. In the entire cohort and several subgroups, the median treatment duration of triple therapy was 55-87 days. DAPT use for 12 months was the most common treatment pattern (62.6%) in the DAPT group (median treatment duration, 324-345 days). A significant discrepancy exists between the current guidelines and real-world practice regarding antithrombotic treatment with PCI for patients with AF. Appropriate use of anticoagulants should be emphasized.

Impact of Reduced-Dose Nonvitamin K Antagonist Oral Anticoagulants on Outcomes Compared to Warfarin in Korean Patients with Atrial Fibrillation: A Nationwide Population-Based Study.

Reduced-dose nonvitamin K antagonist oral anticoagulants (NOACs) are commonly prescribed to Asian patients with nonvalvular atrial fibrillation (NVAF). We aimed to compare the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) between patients treated with reduced-dose NOACs and those treated with warfarin, using the claims database in Korea. Patients with NVAF newly initiated on oral anticoagulants (OACs; apixaban, dabigatran, rivaroxaban, and warfarin) between 1 July 2015 and 30 November 2016 were included. Among all patients with NVAF treated with OACs, 5249, 6033, 7602, and 8648 patients were treated with reduced-dose apixaban, dabigatran, rivaroxaban, and warfarin, respectively. Patients treated with reduced-dose NOACs were older and had higher CHA2DS2-VASc and HAS-BLED scores than those treated with warfarin. Compared to warfarin, all reduced-dose NOACs showed significantly lower risk of S/SE (hazard ratios (95% confidence interval), 0.63 (0.52-0.75) for apixaban; 0.51 (0.42-0.61) for dabigatran; and 0.67 (0.57-0.79) for rivaroxaban) and MB (0.54 (0.45-0.65) for apixaban; 0.58 (0.49-0.69) for dabigatran; 0.73 (0.63-0.85) for rivaroxaban). In the real-world practice among Asians with NVAF, all reduced-dose NOACs were associated with a significantly lower risk of S/SE and MB compared to those of warfarin.

High density mapping guided partial antral ablation for a pulmonary vein isolation.

The muscular discontinuities at the pulmonary vein (PV)-left atrial (LA) junction are known. The high-density mapping may help to find the muscular discontinuity. This study evaluated the efficacy of a partial antral ablation for a pulmonary vein (PV) isolation using high density (HD) mapping. A total of 60 drug-refractory atrial fibrillation (AF) patients undergoing catheter ablation were enrolled. The detailed activation mapping of each PV and LA junction was performed using an HD mapping system, and each PV segment's activation pattern was classified into a "directly-activated from the LA" or "passively-activated from an adjacent PV segment" pattern. The antral ablations were performed at the directly-activated PV segments only when the PV had "passively-activated segments". If the PV did not contain passively-activated segments, a circumferential antral ablation was performed on those PVs. A "successful partial antral ablation" was designated if the electrical isolation of targeted PV was achieved by ablation at the directly-activated segments only. If the isolation was not achieved even though all directly-activated segments were ablated, a "failed partial antral ablation" was designated, and then a circumferential ablation was performed. Among 240 PVs, passively-activated segments were observed in 140 (58.3%) PVs. Both inferior PVs had more passively-activated segments than superior PVs, and the posteroinferior segments had the highest proportion of passive activation. The overall rate of successful partial antral ablation was 85%. The atrial tachyarrhythmia recurrence was observed in 10 patients (16.7%) at 1-year. HD mapping allowed the evaluation of the detailed activation patterns of the PVs, and passively-activated segments may represent muscular discontinuity. Partial antral ablation of directly-activated antral segments only was feasible and effective for a PVI.

Ablation of persistent atrial fibrillation based on high density voltage mapping and complex fractionated atrial electrograms: A randomized controlled trial.

INTRODUCTION: Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) catheter ablation. However, a PVI alone has been considered insufficient for persistent AF. This study aimed to evaluate the efficacy of persistent AF ablation targeting complex fractionated atrial electrogram (CFAE) areas within low voltage zones identified by high-resolution mapping in addition to the PVI. METHODS: We randomized 50 patients (mean age 58.4 ±â€Š9.5 years old, 86.0% males) with persistent AF to a PVI + CFAE group and PVI only group in a 1:1 ratio. CFAE and voltage mapping was performed simultaneously using a Pentaray Catheter with the CARTO3 CONFIDENSE module (Biosense Webster, CA, USA). The PVI + CFAE group, in addition to the PVI, underwent ablation targeting low voltage areas (<0.5 mV during AF) containing CFAEs. RESULTS: The mean persistent AF duration was 24.0 ±â€Š23.1 months and mean left atrial dimension 4.9 ±â€Š0.5 cm. In the PVI + CFAE group, AF converted to atrial tachycardia (AT) or sinus rhythm in 15 patients (60%) during the procedure. The PVI + CFAE group had a higher 1-year AF free survival (84.0% PVI + CFAE vs 44.0 PVI only, P = .006) without antiarrhythmic drugs. However, there was no difference in the AF/AT free survival (60.0% PVI + CFAE vs 40.0% PVI only, P = .329). CONCLUSION: Persistent AF ablation targeting CFAE areas within low voltage zones using high-density voltage mapping had a higher AF free survival than a PVI only. Although recurrence with AT was frequent in the PVI+CFAE group, the sinus rhythm maintenance rate after redo procedures was 76%.