Edoxaban treatment in atrial fibrillation in routine clinical care: One-year outcomes of the prospective observational ETNA-AF study in South Korean patients.

Background: The real-world outcomes of edoxaban treatment in patients with atrial fibrillation (AF) were analyzed in the ETNA-AF (Edoxaban Treatment in Routine Clinical Practice) study involving data from multiple regional registries. This report addresses effectiveness and safety of edoxaban in the Korean ETNA-AF population. Methods: One-year data from 1887 Korean ETNA-AF participants were analyzed according to edoxaban dose and patient age and compared with results of other ETNA-AF registries. Results: Approximately 70% of patients received the recommended doses of edoxaban (60 mg/30 mg); non-recommended 60 mg and 30 mg doses were prescribed to 9.6% and 19.8% of the patients, respectively. The proportions of reference age (<65 years), youngest-old (65-74 years) and middle-old/oldest-old (≥75 years) groups were 21.4%, 40.2%, and 38.4%, respectively. Incidence of major or clinically relevant nonmajor bleeding was similar within dose (0.57%-1.71%) and age subgroups (1.26%-1.63%). Incidence of net clinical outcome, a composite of stroke, systemic embolic event, major bleeding, and all-cause mortality, was also comparable among dose subgroups (1.14%-3.10%) and age subgroups (2.28%-2.78%). The percentage of Korean patients receiving non-recommended 30 mg (19.8%) was over twice that of the European population (8.4%). However, the clinical outcomes were generally similar among different populations included in the ETNA-AF study. Conclusions: The outcomes in the Korean ETNA-AF population are like those in the global ETNA-AF population, with overall low event rates of stroke, major bleeding and all-cause mortality across age and dose subgroups. Edoxaban can be used effectively and safely in specific populations of Korean AF patients, including the elderly.

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.

Surface ECG-based complexity parameters for predicting outcomes of catheter ablation for nonparoxysmal atrial fibrillation: efficacy of fibrillatory wave amplitude.

Catheter ablation (CA) is a well-established therapy for rhythm control in atrial fibrillation (AF). However, CA outcomes for persistent AF remain unsatisfactory because of the high recurrence rate despite time-consuming efforts and the latest ablation technology. Therefore, the selection of good responders to CA is necessary. Surface electrocardiography (sECG)-based complexity parameters were tested for the predictive ability of procedural termination failure during CA and late recurrence of atrial arrhythmias (AA) after CA. A total of 130 patients with nonparoxysmal AF who underwent CA for the first time were investigated. A 10-second sECG of 4 leads (leads I, II, V1, and V6) was analyzed to compute the fibrillatory wave amplitude (FWA), dominant frequency (DF), spectral entropy (SE), organization index (OI), and sample entropy (SampEn). The study endpoints were procedural termination failure during CA and late (≥1 year) AA recurrence after CA. In the multivariate analysis, FWA in lead V1 and DF in lead I were independent predictors of successful AF termination during CA (P <.05). The optimal cut-off values for FWA in lead V1 and DF in lead I were 60.38 µV (area under the curve [AUC], 0.672; P = .001) and 5.7 Hz (AUC, 0.630; P = .016), respectively. The combination of FWA of lead V1 and DF of lead I had a more powerful odds ratio for predicting procedural termination failure (OR, 8.542; 95% CI, 2.938-28.834; P < .001). FWA in lead V1 was the only independent predictor of late recurrence after CA. The cut-off value is 65.73 µV which was 0.634 of the AUC (P = .009). These sECG parameters, FWA in lead V1 and DF in lead I, predicted AF termination by CA in patients with nonparoxysmal AF. In particular, FWA in lead V1 was an independent predictor of late recurrence of AA after CA.

XaMINA: A Real-World, Prospective, Observational Study of Treatment-Naïve Patients Treated with Rivaroxaban for Stroke Prevention in Atrial Fibrillation in Asia.

INTRODUCTION: The efficacy and safety of rivaroxaban for the prevention of stroke and systemic embolism have been demonstrated in Asian and non-Asian patients with non-valvular atrial fibrillation (NVAF) in multiple studies. However, limited published data exist on its use specifically in treatment-naïve patients from the Asia region. Patients in South Korea and Taiwan can now receive rivaroxaban as first-line therapy, allowing for data generation in this patient group. METHODS: XaMINA was a prospective, real-world, multicenter, single-arm, observational cohort study of patients with NVAF in South Korea and Taiwan naïve to anticoagulation and initiating rivaroxaban. The primary outcome was major bleeding; secondary outcomes included all-cause mortality, symptomatic thromboembolic events, and treatment persistence. RESULTS: In total, 1094 patients were included and the follow-up was 1 year. The baseline mean CHADS2 score was 1.63 ± 0.98, mean CHA2DS2-VASc score was 2.92 ± 1.42, and mean HAS-BLED score was 1.00 ± 0.75. The primary outcome occurred in 20 (1.8%) patients [incidence rate 2.1 events per 100 patient-years (95% CI 1.35-3.25)]. Thromboembolic events occurred in 9 (0.8%) patients, of whom 5 (0.5%) had stroke, 3 (0.3%) myocardial infarction, and 1 (0.1%) a transient ischemic attack. There were no cases of non-central nervous system systemic embolism, and 735 (67.2%) patients persisted with rivaroxaban treatment for 1 year. CONCLUSION: XaMINA demonstrated low incidence rates of major bleeding events and thromboembolic events in patients with NVAF newly initiating rivaroxaban in South Korea and Taiwan, consistent with previous real-world studies reconfirming the results of the ROCKET AF study. TRIAL REGISTRATION: The trial was registered on ClinicalTrials.gov (identifier NCT03284762) on 15 September 2017.

Long-Term Safety and Efficacy of Prolonged Dual Antiplatelet Therapy according to Baseline Anemia after Percutaneous Coronary Intervention.

PURPOSE: We aimed to evaluate the outcomes of prolonged dual antiplatelet therapy (DAPT) depending on baseline anemia after percutaneous coronary intervention (PCI). MATERIALS AND METHODS: Among the 1470 study participants, 448 (30.5%) were classified as having baseline anemia. We categorized the study population according to baseline anemia and DAPT duration: ≤12-month (m) DAPT (n=226) vs. >12-m DAPT (n=222) in anemic patients, and ≤12-m DAPT (n=521) vs. >12-m DAPT (n=501) in non-anemic patients. RESULTS: During a follow-up of 80.8 (interquartile range 60.6-97.1) months, anemic patients showed a higher incidence of major adverse cardiovascular and cerebrovascular events (MACCEs) (26.9% vs. 17.1%, p<0.001) and major bleeding (9.8% vs. 5.1%, p=0.006). Among the non-anemic patients, prolonged DAPT was associated with a reduced rate of MACCEs [inverse probability of treatment weighting (IPTW) adjusted hazard ratio (HR), 0.78; 95% confidence interval (CI), 0.63-0.96; p=0.019] without an increase in major bleeding (IPTW adjusted HR, 1.12; 95% CI, 0.75-1.68; p=0.574). However, prolonged DAPT was not related to the incidence of MACCEs (IPTW adjusted HR, 1.11; 95% CI, 0.88-1.39; p=0.387), with increased major bleeding (IPTW adjusted HR, 2.01; 95% CI, 1.32-3.06; p=0.001) among anemic patients. CONCLUSION: Although extended DAPT led to a reduction in MACCEs in non-anemic patients, it was related to increased major bleeding without reducing MACCEs in anemic patients.

Long-term clinical impact of low-density lipoprotein cholesterol target attainment according to lesion complexity after percutaneous coronary intervention.

OBJECTIVE: Long-term clinical outcomes of low-density lipoprotein cholesterol (LDL-C) target attainment according to coronary lesion complexity are limited. We investigated the clinical outcomes of LDL-C target attainment after percutaneous coronary intervention (PCI) according to coronary lesion complexity. METHODS: A total of 1285 patients who underwent PCI was categorized by LDL-C target attainment at 1 year and lesion complexity: LDL-C levels less than or equal to 70 mg/dl ( n = 179) and greater than 70 mg/dl ( n = 308) in complex PCI; LDL-C levels less than or equal to 70 mg/dl ( n = 315) and greater than 70 mg/dl ( n = 483) in noncomplex PCI. The primary endpoint was major adverse cardiovascular events (MACEs) and defined as cardiac death, nonfatal myocardial infarction, and target vessel revascularization. RESULTS: At 8-year follow-up, comparison of patients with 1-year LDL-C levels less than or equal to 70 mg/dl and 1-year LDL-C levels greater than 70 mg/dl showed similar MACE incidence in the noncomplex PCI group (8.3% vs. 11.6%; P = 0.074) and significantly lower MACE incidence in the complex PCI group (11.7% vs. 19.2%; P = 0.023). After IPTW adjustment, 1-year LDL-C levels less than or equal to 70 mg/dl was associated with reduced MACE rate in both complex PCI and noncomplex PCI groups. CONCLUSION: Although the attainment of LDL-C levels less than or equal to 70 mg/dl was associated with reduced MACE rate in both complex PCI and noncomplex PCI groups, long-term clinical benefits were prominent in the complex PCI group.

Long-term effects of the mean hemoglobin A1c levels after percutaneous coronary intervention in patients with diabetes.

BACKGROUND/AIMS: The clinical benefit of strict blood glucose-lowering therapy for patients with coronary artery disease (CAD) is still debated. We aimed to evaluate the long-term outcomes of patients with diabetes who underwent percutaneous coronary intervention (PCI), according to the mean hemoglobin A1c (HbA1c) level after PCI. METHODS: We evaluated 675 diabetes patients with CAD treated with PCI. We categorized the study population into three groups based on the mean observed HbA1c levels during the follow-up duration, as follows: aggressive control (AC) group (HbA1c level < 6.5%, n = 148), moderate control (MC) group (HbA1c level ≥ 6.5% and < 7.0%, n = 138), and uncontrolled (UC) group (HbA1c level ≥ 7.0%, n = 389). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCEs), defined as cardiac death, myocardial infarction, repeat target vessel revascularization, and stroke. RESULTS: The mean HbA1c level of the AC group was significantly lower than that of the MC and UC groups (6.04% ± 0.36% vs. 6.74% ± 0.14% vs. 8.39% ± 1.20%, p < 0.001). The incidence of MACCEs was significantly lower in the AC group than in the MC and UC groups (16.0% vs. 24.3% vs. 26.3%, p = 0.010), mostly driven by the incidence of stroke (4.4% vs. 14.0% vs. 11.4%, p = 0.013). Multivariate Cox regression analysis showed that only the AC group was associated with a reduced rate of MACCEs (hazard ratio, 0.499; 95% confidence interval, 0.316 to 0.786; p = 0.004) compared with the UC group. CONCLUSION: Our study showed that intensive glycemic control (HbA1c level < 6.5%) is associated with improved clinical outcomes after PCI in patients with diabetes.

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.

Clinical impact of blood pressure variability in patients with COVID-19 and hypertension.

OBJECTIVE: This study aimed to investigate the relationship between blood pressure variability (BPV) and clinical outcomes in patients with coronavirus disease 2019 (COVID-19) and hypertension. METHODS: A total of 136 patients hospitalized with COVID-19 were enrolled in this study. Patients were grouped according to the presence of hypertension and BPV. Mean arterial pressure (MAP) measured at 8 a.m. and 8 p.m. was analyzed, and BPV was calculated as the coefficient of variation of MAP (MAPCV). High BPV was defined as MAPCV values above the median. We compared the age, level of C-reactive protein (CRP), creatine kinase-MB (CK-MB), N-terminal pro-B type natriuretic peptide (NT-proBNP), creatinine and in-hospital mortality and investigated the relationship among the groups. RESULTS: COVID-19 patients with hypertension were older (70 ± 12 vs. 53 ± 17 years; P < 0.001), had higher levels of CRP (9.4 ± 9.2 vs. 5.3 ± 8.2 mg/dL; P = 0.009), MAPCV (11.4 ± 4.8 vs. 8.9 ± 3.2; P = 0.002), and higher in-hospital mortality (19.6% vs. 5.9%; P = 0.013) than those without hypertension. There was a proportional relationship between BPV and age, levels of CRP, CK-MB, NT-proBNP, creatinine and in-hospital mortality (all, P < 0.05). In Cox regression analysis, advanced age [≥80 years, hazard ratio (HR) 10.4, 95% confidence interval (CI) 2.264-47.772, P = 0.003] and higher MAPCV (HR 1.617, 95% CI, 1.281-2.040, P < 0.001) were significantly associated with in-hospital mortality. CONCLUSION: High BPV in COVID-19 patients with hypertension is significantly associated with in-hospital mortality. Advanced age and systemic inflammation are proportional to high BPV. Additional attention is needed for COVID-19 patients with hypertension and high BPV.

Clinical Impact of Dysglycemia in Patients with an Acute Myocardial Infarction.

This study aimed to determine the impact of dysglycemia on myocardial injury and cardiac dysfunction in acute myocardial infarctions (AMIs). From 2005 to 2016, a total of 1,593 patients with AMIs who underwent percutaneous coronary intervention were enrolled. The patients were classified into five groups according to the admission glucose level: ≤80, 81 to 140, 141 to 200, 201 to 260, and ≥261 mg/dL. The clinical and echocardiographic parameters and 30-day mortality were analyzed. The peak troponin I and white blood cell levels had a positive linear relationship to the admission glucose level. The left ventricular ejection fraction had an inverted U-shape trend, and the E/E' ratio was U-shaped based on euglycemia. The 30-day mortality also increased as the admission glucose increased, and the cut-off value for predicting the mortality was 202.5 mg/dL. Dysglycemia, especially hyperglycemia, appears to be associated with myocardial injury and could be another adjunctive parameter for predicting mortality in patients with AMIs.

A prospective, observational study of rivaroxaban for stroke prevention in atrial fibrillation: the XANAP Korea.

BACKGROUND/AIMS: Atrial fibrillation (AF)-related stroke accounts for 20% of ischemic strokes. Rivaroxaban use in AF patients for preventing stroke and systemic embolism was approved in 2013 in Korea. This study was to investigate the safety and effectiveness of rivaroxaban use in Korean patients with non-valvular AF in a real-world setting. METHODS: This was an analysis of the Korean patients in Xarelto for Prevention of Stroke in Patients with Atrial Fibrillation in Asia-Pacific (XANAP), which was a prospective, observational cohort study including patients with non-valvular AF starting rivaroxaban treatment to prevent stroke or non-central nervous system systemic embolism (non-CNS SE), conducted in 10 Asian countries. RESULTS: A total of 844 patients were enrolled in the Korean portion of the XANAP study. In XANAP Korea, the mean age was 70.1 years and 62.6% were males. The mean CHADS2 score was 2.5 and the mean CHA2DS2-VASc score was 3.8. 47% of the patients had experienced prior stroke or non-CNS SE or transient ischemic attack. 73.6% of the patients had CHADS2 score ≥ 2. Incidence proportions of 0.8% of the patients (1.1 per 100 patient-years) developed adjudicated treatment-emergent major bleeding. Death was observed in 1.2% of the patients. The incidence of non-major bleeding as well as thromboembolic event were 8.4% (11.6 per 100 patient-years) and 1.5% (2.0 per 100 patient-years), respectively. CONCLUSION: This study reaffirmed the consistent safety profile of rivaroxaban. We found consistent results with overall XANAP population for rivaroxaban in terms of safety in non-valvular AF patients for the prevention of stroke and non-CNS SE.

Adherence to dabigatran and the influence of dabigatran-induced gastrointestinal discomfort in the real-world practice.

BACKGROUND: Dabigatran-induced gastrointestinal discomfort (DGID) is an important factor influencing the adherence to dabigatran. We investigated the incidence and risk factors of DGID and its impact on the adherence and persistence to dabigatran. METHODS: We prospectively enrolled the patients prescribed with dabigatran in 10 tertiary hospitals of the South Korea. The adherence was assessed using the percentage of the prescribed doses of the medication presumably taken by the patient (PDT by pill count). We evaluated the relationship between DGID and the baseline GI symptoms or the previous GI disease history using a questionnaire. RESULTS: A total of 474 patients (mean age 67.8 ± 9.3 years, male 68.6%, and mean CHA2DS2-VASc score 2.2 ± 1.2) were enrolled. The adherence assessed by the PDT was 93.5 ± 5.5% at 1-month and 96.4 ± 8.4% at 6-months among the persistent patients. During the 6-month follow-up, 82 (18.1%) patients discontinued dabigatran, and the most common reason for dabigatran discontinuation was DGID (49, 59.8%). Sixty-eight (14.3%) patients experienced DGID, and there was no difference in the clinical factors between those with or without DGID. Among the patients who experienced DGID, 42 discontinued dabigatran (61.8%). In a multivariate analysis, DGID was the only predictor of dabigatran discontinuation and a low adherence. CONCLUSION: Overall adherence of dabigatran was excellent, but those with DGID showed low adherence and persistence. Furthermore, it was challenging to predict DGID by clinical parameters. Therefore, it is recommended to follow the patients closely to check for DGID when prescribing dabigatran.

Clinical Implication of 'Obesity Paradox' in Elderly Patients With Acute Myocardial Infarction.

BACKGROUND: The clinical impact of body mass index (BMI), especially in the elderly with acute myocardial infarction (AMI), has not been sufficiently evaluated. The purpose of this study was to elucidate the clinical impact of BMI in very old patients (≥80 years) with AMI. METHODS: The study analysed 2,489 AMI patients aged ≥80 years from the Korea Acute Myocardial Infarction Registry and the Korea Working Group on Myocardial Infarction (KAMIR/KorMI) registries between November 2005 and March 2012. The study population was categorised into four groups based on their BMI: underweight (n=301), normal weight (n=1,150), overweight (n=890), and obese (n=148). The primary endpoint was major adverse cardiovascular event (MACE), a composite of cardiac death, myocardial infarction, target lesion revascularisation, and target vessel revascularisation. RESULTS: Baseline characteristics among the four groups were similar, except for hypertension (45.1 vs 58.4 vs 66.2 vs 69.9%, respectively; p<0.001) and diabetes (16.6 vs 23.6 vs 30.7 vs 35.1%, respectively; p<0.001). Coronary care unit length of stay was significantly different among the four groups during hospitalisation (5.3±5.9 vs 4.8±6.8 vs 4.2±4.0 vs 3.5±2.1 days; p=0.007). MACE (16.9 vs 14.9 vs 13.7 vs 8.8%; p=0.115) and cardiac death (10.3 vs 8.4 vs 7.9 vs 4.1%; p=0.043) less frequently occurred in the obese group than in other groups during the 1-year follow-up. A multivariate regression model showed obese status (BMI ≥27.5 kg/m2) as an independent predictor of reduced MACE (hazard ratio [HR], 0.20; 95% confidence interval [CI], 0.06-0.69; p=0.010) along with reduced left ventricular ejection fraction (≤40%) as a predictor of increased MACE (HR,1.87; 95% CI, 1.31-2.68; p=0.001). CONCLUSION: Body mass index in elderly patients with acute myocardial infarction was significantly associated with coronary care unit stay and clinical cardiovascular outcomes.

Clinical Impact of Implantable Cardioverter-Defibrillator Therapy and Mortality Prediction Model for Effective Primary Prevention in Korean Patients.

BACKGROUND: Studies on the efficacy of implantable cardioverter-defibrillator (ICD) therapy for primary prevention in Asian patients are relatively lacking compared to those for secondary prevention. Also, it is important to stratify which patients will benefit from ICD therapy for primary prevention. METHODS: Of 483 consecutive patients who received new implantation of ICD in 9 centers in Korea, 305 patients with reduced left ventricular systolic function and/or documented ventricular fibrillation/tachycardia were enrolled and divided into primary (n = 167) and secondary prevention groups (n = 138). RESULTS: During mean follow-up duration of 2.6 ± 1.6 years, appropriate ICD therapy occurred in 78 patients (25.6%), and appropriate ICD shock and anti-tachycardia pacing occurred in 15.1% and 15.1% of patients, respectively. Appropriate ICD shock rate was not different between the two groups (primary 12% vs. secondary 18.8%, P = 0.118). However, appropriate ICD therapy rate including shock and anti-tachycardia pacing was significantly higher (primary 18% vs. secondary 34.8%, P = 0.001) in the secondary prevention group. Type of prevention and etiology, appropriate and inappropriate ICD shock did not affect all-cause death. High levels of N-terminal pro-B-type natriuretic peptide, New York Heart Association functional class, low levels of estimated glomerular filtration ratio, and body mass index were associated with death before appropriate ICD shock in the primary prevention group. When patients were categorized in 5 risk score groups according to the sum of values defined by each cut-off level, significant differences in death rate before appropriate ICD shock were observed among risk 0 (0%), 1 (3.6%), 2 (3%), 3 (26.5%), and 4 (40%) (P < 0.001). CONCLUSION: In this multicenter regional registry, the frequency of appropriate ICD therapy is not low in the primary prevention group. In addition, combination of poor prognostic factors of heart failure is useful in risk stratification of patients who are not benefiting from ICD therapy for primary prevention.

Impact of Oxidative Stress on Long-Term Heart Rate Variability: Linear Versus Non-Linear Heart Rate Dynamics.

BACKGROUND: Heart rate variability (HRV) is a widely used non-invasive and quantitative marker of cardiac autonomic control. Elevated oxidative stress (OS) and reduced HRV have been proven in specific disease subsets. However, the impact of OS on the long-term heart rate dynamics of both conventional linear and non-linear origin in the general population is not known. METHODS: The 24-hour ambulatory electrocardiogram recordings and plasma 8-iso-prostaglandin F2α (8-iso-PGF2α) levels as an OS marker were acquired simultaneously in 71 consecutive patients. The conventional time and frequency domain HRV parameters and non-linear parameters were measured. RESULTS: The 8-iso-PGF2α is a significant determinant of most long-term conventional time and frequency domain HRV parameters and standard deviation (SD1, perpendicular to the line of identity; SD2, along the line of identity) descriptors from Poincaré plot analysis, but not of non-linear complexity and fractal parameters. Patients with a high OS burden had lower absolute low-frequency and high-frequency powers during both the night and morning periods, with a significant decrease in high-frequency power in the morning. CONCLUSIONS: Oxidative stress is one of the significant determinants of the HRV. The severity of OS is reflected in the conventional time and frequency domain HRV parameters, but not in the non-linear measurements.

Status of international normalized ratio control and treatment patterns in patients with nonvalvular atrial fibrillation taking vitamin K antagonist with or without antiplatelet therapy: Results from KORAFII registry.

BACKGROUND: Studies have shown that the concomitant use of a vitamin K antagonist (VKA) and an antiplatelet (APL) drug increased the bleeding risk and was less effective at preventing ischemic events. This study aimed to investigate the control status of international normalized ratio (INR) and the discontinuation rate of a VKA in patients taking VKA plus an APL drug compared with those taking a VKA alone. METHODS: Data were extracted from the KORean Atrial Fibrillation Investigation II registry, a multicenter noninterventional prospective observational study. Nonvalvular atrial fibrillation (NVAF) patients with CHADS 2 scores ≥ 1 who newly started (within 3 months) a VKA were enrolled and followed up for 1 year. RESULTS: A total of 866 NVAF patients (mean age, 67.7 years; 60.3% men) without a bleeding history were divided into the VKA+APL (n = 229) and VKA alone (n = 637) groups. During follow-up, mean INR level was lower in the VKA+APL group than in the VKA alone group (1.7 ± 0.8 vs 1.9 ± 0.9, P = 0.0005). INR levels were poorly controlled in both groups (66.1% and 64.7%, respectively). Patients in the VKA+APL group more frequently discontinued VKA than patients in the VKA alone group (28.8% vs 24.2%, P = 0.045). Major causes of VKA discontinuation were uncontrolled INR level and patient dissatisfaction or concerns. CONCLUSIONS: The conditions of NVAF patients were inadequately controlled with VKA with or without an APL. These findings suggest that other antithrombotic treatment options are warranted in NVAF patients to achieve INR control.

Long-term clinical outcomes according to the mean observed blood pressure in patients with coronary artery disease after drug-eluting stent implantation.

BACKGROUND: A recent guideline emphasized strict blood pressure (BP) control for the patients at high risk for cardiovascular events. However, there are little data about the relationship between BP control and clinical outcome in Korea. We sought to evaluate the clinical outcomes according to the mean observed BP in patients with coronary artery disease (CAD) who had undergone drug-eluting stent (DES) implantation. METHODS: We reviewed records of 1010 CAD patients with DES from 2010 through 2011. After excluding in-hospital mortality cases (n = 79), we categorized patients into two groups based on the average SBP (SBP) at the outpatient clinic: mean SBP 120 mmHg or less (n = 290) and mean SBP greater than 120 mmHg (n = 641). Primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCEs), defined as cardiac death, myocardial infarction, repeat target vessel revascularization, or stroke. Propensity score matching was performed to adjust for differences in baseline clinical variables. Median follow-up duration was 77.7 (36.6-87.3) months. RESULTS: The mean SBP greater than 120 mmHg had higher prevalence of cardiovascular risk factors, such as diabetes (38.4 vs. 27.2%, P = 0.001), hypertension (58.8 vs. 32.4%, P < 0.001), and chronic kidney disease (3.3 vs. 1.0%, P = 0.043) than mean SBP 120 mmHg or less. MACCE incidence was significantly lower in the mean SBP 120 mmHg or less than in the mean SBP greater than 120 mmHg (14.3 vs. 22.0%, P = 0.007) at 77.7 months. Even after propensity score matching, the mean SBP 120 mmHg or less showed significantly reduced MACCE rate (14.3 vs. 22.8%, P = 0.007). CONCLUSION: Mean observed SBP 120 mmHg or less was associated with a lower incidence of future adverse outcomes in CAD patients with DES.