Optimal intensity of warfarin therapy for secondary prevention of stroke in patients with nonvalvular atrial fibrillation : a multicenter, prospective, randomized trial. Japanese Nonvalvular Atrial Fibrillation-Embolism Secondary Prevention Cooperative Study Group

Thirty-year outcomes of low-intensity anticoagulation for mechanical aortic valve

The long-term safety, efficacy, and outcomes of low-intensity anticoagulation for mechanical heart valves remain unclear. This study aimed to evaluate the long-term outcomes of low-intensity anticoagulation therapy after aortic valve replacement (AVR) with a mechanical prosthesis. This retrospective cohort study consulted medical records and conducted a questionnaire to investigate 519 patients who underwent single AVR with the St. Jude Medical bileaflet valve and were in sinus rhythm. All patients were followed up with an international normalized ratio (INR) target of 1.6-2.5, and their INR values were checked throughout the follow-up period. The survival rate, incidence of major adverse cardiac and cerebrovascular events (MACCE), and risk factors for cardiac death and MACCE were investigated. The total follow-up was 9793 patient-years, and the follow-up periods were 19.9 (standard deviation [SD]: 7.9) years. The mean INR was 2.03 (SD: 0.54). Survival rates from cardiac death were 93.6% in 20 years and 85.2% in 30 years. Advanced age ≥ 70 years was the only significant risk factor for cardiac death and MACCE, and the INR < 2.0 was not significant risk factor for MACCE including thromboembolism or bleeding events. Low-intensity anticoagulation with an INR of 1.6-2.5 for patients with sinus rhythm after AVR with a bileaflet mechanical valve is safe and effective, even over 30 years.

Net clinical benefit of oral anticoagulants in Asian patients with atrial fibrillation based on a CHA2DS2-VASc score

BACKGROUND

This study was conducted to assess the net clinical benefit (NCB) for oral anticoagulant (OAC) in atrial fibrillation (AF) patients according to the CHA2DS2-VASc score.

METHODS

Patients with AF were prospectively recruited in the COOL AF Thailand registry from 2014 to 2017. The incidence rate of thromboembolic (TE) events and major bleeding (MB) was calculated. Cox proportional hazards model was used to compare the TE and MB rate in patients with and without OACs in CHA2DS2-VASc score of 0-1 and ≥ 2, respectively. The survival analysis was performed based on CHA2DS2-VASc score. The NCB of OACs was defined as the TE rate prevented minus the MB rate increased multiplied by a weighting factor.

RESULTS

A total of 3,402 AF patients were recruited. An average age of patients was 67.38 ± 11.27 years. Compared to non-anticoagulated patients, the Kaplan Meier curve showed anticoagulated patients with CHA2DS2-VASc score of 2 or more had the lower thromboembolic events with statistical significance (p = 0.043) and the higher MB events with statistical significance (p = 0.018). In overall AF patients, there were positive NCB in warfarin patients with CHA2DS2-VASc score of 3 or more while there were positive NCB in DOACs patients regardless of CHA2DS2-VASc score. Females with CHA2DS2-VASc score of 3 or more had a positive NCB regardless of OACs type. Good anticoagulation control (TTR ≥65%) improved an NCB in males with CHA2DS2-VASc score of 3 or more.

CONCLUSIONS

AF patients with CHA2DS2-VASc score of 3 or more regardless warfarin or DOACs had a positive NCB. The NCB of OACs was more positive for DOACs compared to warfarin and for females compared to males.

Impact of cilostazol on prevention of late failure of autologous vein grafts

OBJECTIVES

The effectiveness of postoperative medication for the prevention of late graft failure is controversial. We conducted the present study to investigate whether cilostazol improved the mid-term outcomes after infrainguinal autologous vein bypass for chronic limb-threatening ischemia (CLTI).

METHODS

From April 1994 to March 2022, we performed 590 de novo infrainguinal bypass procedures using autologous vein grafts (AVGs) in three hospitals. The bypass grafts were classified according to the postoperative prescription of cilostazol. The loss of graft patency and major adverse limb events (MALEs) were set as endpoints. Patients who died within 30 days and grafts that lost primary patency within 30 days after surgery were excluded. Data up to 3 years were analyzed. The cumulative primary patency (PP), assisted primary patency (AP), secondary patency (SP), and freedom from MALE (ffMALE) rates were calculated by the Kaplan-Meier method and compared between the cilostazol group and the non-cilostazol group. After a propensity score matching, same statistical analyses were performed. In addition, a Cox proportional hazards regression analysis that included preoperative factors, intraoperative factors, and postoperative medications was performed to identify whether cilostazol is an independent predictor for the outcomes.

RESULTS

A total of 523 AVGs met inclusion criteria. Kaplan-Meier curves showed that the cilostazol group was superior to the non-cilostazol group in all outcomes, while the cilostazol group was superior to the non-cilostazol group in AP and SP after a propensity score matching. A multivariable analysis showed that non-use of cilostazol was identified as an independent predictor for loss of AP, SP, and ffMALE.

CONCLUSIONS

Cilostazol improved the mid-term outcomes after infrainguinal autologous vein bypass.

Standard-Intensity Versus Low-Intensity Anticoagulation with Warfarin in Asian Patients with Atrial Fibrillation: A Multi-Center, Randomized Controlled Trial

Anticoagulation with warfarin in Asian patients with atrial fibrillation (AF) often has been decreased as an international normalized ratio (INR) of prothrombin time 1.6-2.6 due to fear of bleeding, although universal criteria recommend an INR of 2.0-3.0. In this randomized, open-label trial, low-intensity anticoagulation (INR 1.6-2.6) was compared with standard-intensity anticoagulation (INR 2.0-3.0) with warfarin. A total 616 patients with AF and at least 1 risk factor for stroke were randomized to low-intensity anticoagulation (n = 308) and standard-intensity anticoagulation (n = 308) groups. The intention-to-treat analysis was performed to determine differences. The baseline characteristics of the two groups were comparable. New-onset stroke occurred in 2 patients (0.44% per year) in the low-intensity group and 5 patients (1.05% per year) in the standard-intensity group (HR 0.42, 95% CI 0.08-2.15). Major bleeding occurred in 4 patients (0.89% per year) in the low-intensity group and 5 patients (1.06% per year) in the standard-intensity group (HR 0.84, 95% CI 0.22-3.11). The rate of the net clinical outcome (composite of stroke, systemic embolism, major bleeding, and death) was 1.33% per year in the low-intensity group compared with 2.12% per year in the standard-intensity group (HR 0.63, 95% CI 0.23-1.72). In Asian patients with AF, clinical outcomes were not different between low-intensity and standard-intensity anticoagulation with warfarin.

Influence of Renal Impairment and Genetic Subtypes on Warfarin Control in Japanese Patients

The genotypes of vitamin K epoxide reductase complex 1 (VKORC1) and cytochrome P450 2C9 (CYP2C9) can influence therapeutic warfarin doses. Conversely, nongenetic factors, especially renal function, are associated with warfarin maintenance doses; however, the optimal algorithm for considering genes and renal dysfunction has not been established. This single-center prospective cohort study aimed to evaluate the factors affecting warfarin maintenance doses and develop pharmacogenetics-guided algorithms, including the factors of renal impairment and others. To commence, 176 outpatients who were prescribed warfarin for thromboembolic stroke prophylaxis in the stroke center, were enrolled. Patient characteristics, blood test results, dietary vitamin K intake, and CYP2C9 and VKORC1 (-1639G>A) genotypes were recorded. CYP2C9 and VKORC1 (-1639G>A) genotyping revealed that 80% of the patients had CYP2C9 *1/*1 and VKORC1 mutant AA genotypes. Multiple linear regression analysis demonstrated that the optimal pharmacogenetics-based model comprised age, body surface area, estimated glomerular filtration rate (eGFR), genotypes, vitamin K intake, aspartate aminotransferase levels, and alcohol intake. eGFR exercised a significant impact on the maintenance doses, as an increase in eGFR of 10 mL/min/1.73 m² escalated the warfarin maintenance dose by 0.6 mg. Reduced eGFR was related to lower warfarin maintenance doses, independent of VKORC1 and CYP2C9 genotypes in Japanese patients.

Gender differences in comorbidities and risk factors in ischemic stroke patients with a history of atrial fibrillation

BACKGROUND

Atrial Fibrillation (AF) is a common cardiac arrhythmia and has been identified as a major risk factor for acute ischemic stroke (AIS). Gender differences in the disease process, causative mechanisms and outcomes of AF have been investigated. In the current study, we determined whether there is a gender-based disparity in AIS patients with baseline AF, and whether such a discrepancy is associated with specific risk factors and comorbidities.

METHODS

Baseline factors including comorbidities, risk and demographic factors associated with a gender difference were examined using retrospective data collected from a registry from January 2010 to June 2016 in a regional stroke center. Univariate analysis was used to differentiate between genders in terms of clinical risk factors and demographics. Variables in the univariate analysis were further analyzed using logistic regression. The adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for each factor were used to predict the increasing odds of an association of a specific comorbidity and risk factor with the male or female AIS with AF.

RESULTS

In the population of AIS patients with AF, a history of drug and alcohol use (OR = 0.250, 95% CI, 0.497-1.006, P = 0.016), sleep apnea (OR = 0.321, 95% CI, 0.133-0.777, P = 0.012), and higher serum creatinine (OR = 0.693, 95% CI, 0.542-0.886 P = 0.003) levels were found to be significantly associated with the male gender. Higher levels of HDL-cholesterol (OR = 1.035, 95% CI, 1.020-1.050, P < 0.001), LDL-cholesterol (OR = 1.006, 95% CI, 1.001-1.011, P = 0.012), and the inability to ambulate on admission to hospital (OR = 2.258, 95% CI, 1.368-3.727, P = 0.001) were associated with females.

CONCLUSION

Our findings reveal that in the AIS patients with atrial fibrillation, migraines, HDL, LDL and poor ambulation were associated with females, while drugs and alcohol, sleep apnea, and serum creatinine level were associated with male AIS patients with AF. Further studies are necessary to determine whether gender differences in risk factor profiles and commodities require consideration in clinical practice when it comes to AF as a risk factor management in AIS patients.

Indonesian registry on atrial fibrillation (OneAF)

BACKGROUND

Data on the optimal therapeutic international normalized ratio (INR) for non-valvular and valvular atrial fibrillation (AF) in Indonesia is currently unavailable. Therefore, we designed the Indonesian Registry on Atrial Fibrillation (OneAF) registry in order to seek a safe and beneficial range of INR in Indonesian patients with non-valvular and valvular AF.

METHODS/DESIGN

The OneAF registry is a nationwide collaboration of the Indonesian Heart Rhythm Society (InaHRS) enrolling all hospitals with cardiac electrophysiologists in Indonesia. It is a prospective, multicentre, nationwide, observational study aiming to recruit non-valvular and valvular AF patients in Indonesia. The registry was started in January 2020 with a planned 2 years of recruitment. There are 2 respondents for this registry: non-cohort and cohort respondents. Non-cohort registry respondents are AF patients at hospitals who fulfill inclusion and exclusion criteria but did not consent for a 24 month follow up. Whereas patients who consented for a 24 month follow up were included as cohort registry respondents. Key data collected includes basic sociodemographic information, symptoms and signs, medical history, results of physical examination and laboratory test, details of diagnostics and treatment measures and events.

RESULTS

Currently, a total of 1568 respondents have been enrolled in the non-cohort registry, including 1065 respondents with non-valvular AF (67.8%) and 503 respondents with valvular AF (32.2%). We believe that the OneAF registry will provide insight into the regional variability of anticoagulant treatment for AF, the implementation of rhythm/rate control approaches, and the clinical outcomes concerning cardiocerebrovascular events.

TRIAL REGISTRATION

Registered at clinicaltrials.gov (NCT04222868).

Implications and characteristics of high bleeding risk in East Asian patients undergoing percutaneous coronary intervention: Start with what is right rather than what is acceptable

Recent advances in percutaneous coronary intervention (PCI) technology and medication have changed the main focus of PCI from preventing ischemic to preventing bleeding events. Bleeding risk assessment is essential for preventing bleeding. Several types of assessment tools have been established, but they are heterogeneous, making interpretation, generalization, and comparison between trials difficult. In 2019, the Academic Research Consortium (ARC) introduced a new consensus document with 20 criteria to define high bleeding risk (HBR). The applicability of the ARCHBR criteria were subsequently investigated, and 4 studies have already demonstrated wide applicability worldwide, including in Japan. Nevertheless, it hase been suggested that bleeding risk is higher in people from East Asian countries than in people from Western countries. Patients with HBR have a 3-fold higher risk of major bleeding, and in Japan approximately 50% of patients undergoing PCI have HBR. In addition, patients with overlapping factors, such as older age, renal disease, and anemia, are at increased risk of bleeding, and each additional factor further increases the risk. In Japanese patients undergoing PCI, in addition to the ARC-HBR criteria, low body weight, heart failure, and peripheral arterial disease are high-risk subsets for bleeding. The addition of these factors to the ARCHBR criteria increases the prevalence of HBR in Japanese patients to 58% and improves the sensitivity of diagnostic evaluations. The additional factors are clinically important because they are often encountered in everyday practice, and Japan's newly updated guideline has adopted them as criteria for HBR. Studies found a temporal trend over the past 20 years of a gradual and consistent increase of bleeding risk. This finding contrasts with improved outcomes in people at risk of ischemic and thrombotic events. Therefore, further research is needed to eliminate the risk of bleeding while maintaining the efficacy of antithrombotic therapy after PCI.

Optimal INR level in elderly and non-elderly patients with atrial fibrillation receiving warfarin: a report from the COOL-AF nationwide registry in Thailand

BACKGROUND

Asian population are at increased risk of bleeding during the warfarin treatment, so the recommended optimal international normalized ratio (INR) level may be lower in Asians than in Westerners. The aim of this prospective multicenter study was to determine the optimal INR level in Thai patients with non-valvular atrial fibrillation (NVAF).

METHODS

Patients with NVAF who were on warfarin for stroke prevention were recruited from 27 hospitals in the nationwide COOL-AF registry in Thailand. We collected demographic data, medical history, risk factors for stroke and bleeding, concomitant disease, electrocardiogram and laboratory data including INR and antithrombotic medications. Outcome measurements included ischemic stroke/transient ischemic attack (TIA) and major bleeding. Optimal INR level was assessed by the calculation of incidence density for six INR ranges (< 1.5, 1.5-1.99, 2-2.49, 2.5-2.99, 3-3.49, and ≥ 3.5).

RESULTS

A total of 2, 232 patients were included. The mean age of patients was 68.5 ± 10.6 years. The mean follow-up duration was 25.7 ± 10.6 months. There were 63 ischemic stroke/TIA and 112 major bleeding events. The lowest prevalence of ischemic stroke/TIA and major bleeding events occurred within the INR range of 2.0-2.99 for patients < 70 years and 1.5-2.99 for patients ≥ 70 years.

CONCLUSIONS

The INR range associated with the lowest risk of ischemic stroke/TIA and bleeding in the Thai population was 2.0-2.99 for patients < 70 years and 1.5-2.99 for patients ≥ 70 years. The rates of major bleeding and ischemic stroke/TIA were both higher than the rates reported in Western population.

Factors associated with silent cerebral events during atrial fibrillation ablation in patients on uninterrupted oral anticoagulation

INTRODUCTION

Silent cerebral events (SCEs) are related to the potential thromboembolic risk in atrial fibrillation (AF) ablation. Periprocedural uninterrupted oral anticoagulation (OAC) reportedly reduced the risk of SCEs, but the incidence still remains.

METHODS AND RESULTS

AF patients undergoing catheter ablation were eligible. All patients took non-vitamin K antagonist oral anticoagulants (NOACs; n = 248) or vitamin K antagonist (VKA; n = 37) for periprocedural OAC (>4 weeks) without interruption during the procedure. Brain magnetic resonance imaging was performed within 2 days after the procedure to detect SCEs. Clinical characteristics and procedure-related parameters were compared between patients with and without SCEs. SCEs were detected in 66 patients (23.1%; SCE[+]) but were not detected in 219 patients (SCE[-]). Age was higher in SCE[+] than in SCE[-] (66 ± 10 vs. 62 ± 12 years; p < .05). Persistent AF prevalence, CHADS₂ /CHA₂ DS₂ -VASc scores, serum NT-ProBNP levels, left atrial dimension (LAD), and spontaneous echo contrast prevalence in transesophageal echocardiography significantly increased in SCE[+] versus SCE[-]. SCE[+] had lower baseline activated clotting time (ACT) before heparin injection and longer time to reach optimal ACT (>300 s) than SCE[-] (146 ± 27 vs. 156 ± 29 s and 44 ± 30 vs. 35 ± 25 min; p < .05, respectively). In multivariate analysis, age, LAD, baseline ACT, and time to reach the optimal ACT were predictors for SCEs. The average values of the ACT parameters were significantly different among NOACs/VKA.

CONCLUSION

Age, LAD, and intraprocedural ACT kinetics significantly affect SCEs during AF ablation. Different anticoagulants have different impacts on ACT during the procedure, which should be considered when estimating the risk of SCEs.

Antithrombotic therapy for stroke prevention in patients with atrial fibrillation in Japan

INTRODUCTION

Stroke remains one of the major public health problems in Japan. The number of patients with atrial fibrillation (AF) has been steadily increasing with the aging of the Japanese population. Appropriate oral antithrombotic therapy is necessary to prevent AF-related stroke and bleeding complications.

AREAS COVERED

The authors summarize the Japanese guidelines for antithrombotic therapy, as well as the current status of antithrombotic therapy, and future perspectives for antithrombotic therapy for patients with AF in Japan.

EXPERT OPINION

Further improvement in adherence to guideline-recommended warfarin therapy may be difficult to achieve. After the introduction of direct oral anticoagulants (DOACs) into clinical practice, the proportion of patients with AF receiving oral anticoagulant therapy has increased in Japan. However, the proportion of patients treated with inappropriately reduced doses of DOACs has also been increasing. Inappropriate dose reduction of DOACs simply because of advanced age should be avoided to reduce stroke events in patients with AF. Among patients with AF receiving anticoagulant therapy who have coronary artery disease, inappropriately prolonged triple therapy or dual therapy should be avoided to reduce major bleeding complications. Shortening the duration of triple therapy or dual therapy may be promoted by simplified recommendations in the 2020-updated guidelines supported by solid evidence.

Ethnic Differences in Oral Antithrombotic Therapy

Oral antithrombotic therapy (antiplatelet therapy and anticoagulation therapy) is a key element of pharmacotherapy in patients with cardiovascular (CV) disease. Several reports of ethnic differences have suggested that there may be difference therapeutic requirements and response to therapy for antithrombotic therapy. In particular for East Asians, there seems to be a lower incidence of ischemic outcomes and a higher incidence of bleeding outcomes compared to Westerners. The purpose of this review is to describe the ethnicity-related differences in antithrombotic therapy for CV disease and to discuss the need to establish a more effective and targeted antithrombotic treatment strategy in East Asians.

Antithrombotic management and long-term outcomes following percutaneous coronary intervention for acute coronary syndrome in Asia

BACKGROUND

Cardiovascular diseases account for approximately half of all deaths in Asia. The present analysis aimed to evaluate characteristics, antithrombotic management patterns (AMPs), and outcomes in patients with acute coronary syndrome (ACS) who underwent in-hospital percutaneous coronary intervention (PCI) and survived to hospital discharge, using data from the EPICOR Asia registry (NCT01361386).

METHODS

Two-year post-discharge follow-up data were analyzed from 8757 ACS PCI patients from EPICOR Asia (218 centers, eight countries). Major adverse cardiovascular events (MACE; death, non-fatal myocardial infarction [MI], non-fatal ischemic stroke), PCI characteristics, and AMPs were recorded. For MACE, time - to - event was analyzed using Cox regression.

RESULTS

Primary PCI was performed in 62.0% of ST-segment elevation MI (STEMI), 38.7% of non-STEMI (NSTEMI), and 24.2% of unstable angina (UA) patients. At 12 months, 88.1% of patients were on dual antiplatelet therapy (DAPT), with no differences by index event. Most (61.5%) still received DAPT at 2 years. Two-year incidences of mortality, composite MACE, and bleeding were 3.6%, 6.2%, and 6.6%, respectively. Risk of death and MACE was increased with STEMI and NSTEMI vs. UA. Patients from East Asia showed lower mortality and more bleeding vs. Southeast Asia/India.

CONCLUSIONS

Many patients in EPICOR Asia underwent PCI and received DAPT up to 2 years post-discharge. These real-world findings improve our understanding of AMP impact on outcomes in Asian patients with ACS undergoing PCI.

Optimal INR level in patients with atrial fibrillation with EHRA type 2 valvular heart disease receiving warfarin

Background

To date, there has been no study that compares the efficacy and safety of warfarin in atrial fibrillation (AF) patients with Evaluated Heartvalves, Rheumatic or Artificial (EHRA) type 2 valvular heart disease (VHD). This study was conducted to determine the optimal INR in these patients.

Methods

This retrospective study enrolled AF patients with EHRA type 2 VHD receiving warfarin in Central Chest Institute of Thailand between January 2016 and December 2018. The incidence density of thromboembolic or bleeding events was calculated. The International normalized ratio (INR) was classified into six groups (less than 1.50, 1.50 to 1.99, 2.00 to 2.49, 2.50 to 2.99, 3.00 to 3.49, and 3.50 or more). The optimal INR level was defined as the lowest incidence density of thromboembolic events and bleeding complications.

Results

A total of 200 AF patients with EHRA type 2 VHD receiving warfarin were enrolled, contributing to 289 patient‐years of observation period. There were 13 thromboembolic events (4.5 per 100 patient‐years) and 16 bleeding events (5.5 per 100 patient‐years). The incidence density of thromboembolic events was significantly increased in the INR level below 2.00 (P = .03), while the INR level of 3.50 or more was significantly increased in the incidence density of major bleeding events (P = .03). Total bleeding and minor bleeding were increased significantly in INR level of 2.50 or more (P = .04).

Conclusions

The INR of 2.00 to 2.49 was appeared to be associated with the lowest incidence density of thromboembolic and bleeding events in these patients.

Effectiveness and Safety of Off-label Dosing of Non-vitamin K Antagonist Anticoagulant for Atrial Fibrillation in Asian Patients

Non–vitamin K antagonist anticoagulants (NOACs) have been used to prevent thromboembolism in patients with atrial fibrillation (AF) and shown favorable clinical outcomes compared with warfarin. However, off-label use of NOACs is frequent in practice, and its clinical results are inconsistent. Furthermore, the quality of anticoagulation available with warfarin is often suboptimal and even inaccurate in real-world data. We have therefore compared the effectiveness and safety of off-label use of NOACs with those of warfarin whose anticoagulant intensity was accurately estimated. We retrospectively analyzed data from 2,659 and 3,733 AF patients at a tertiary referral center who were prescribed warfarin and NOACs, respectively, between 2013 and 2018. NOACs were used at off-label doses in 27% of the NOAC patients. After adjusting for significant covariates, underdosed NOAC (off-label use of the reduced dose) was associated with a 2.5-times increased risk of thromboembolism compared with warfarin, and overdosed NOAC (off-label use of the standard dose) showed no significant difference in either thromboembolism or major bleeding compared with warfarin. Well-controlled warfarin (TTR ≥ 60%) reduced both thromboembolism and bleeding events. In conclusion, the effectiveness of NOACs was decreased by off-label use of the reduced dose.

Prevalence of and risk factors for postoperative hemorrhage after lower third molar extraction on warfarin therapy: a multicenter retrospective study in Japan

Postoperative hemorrhage after tooth extraction is a critical and clinically important issue for clinicians and patients receiving anticoagulants. The purpose of the present study was to investigate the prevalence of and risk factors for postoperative hemorrhage after lower third molar extraction in Japanese patients receiving warfarin therapy. A total of 142 patients who underwent lower third molar extraction between January 2010 and December 2016 were included, and their medical records were retrospectively reviewed. The prevalence of and risk factors for postoperative hemorrhage were investigated. The prevalence of postoperative hemorrhage after lower third molar extraction was significantly higher in patients receiving warfarin than in healthy subjects (21.8% vs 0.7%, P < 0.001). The cutoff value for PT-INR was 2.11 based on a receiver-operating characteristic analysis. A multivariate analysis indicated that an elevated PT-INR value [hazard ratio (HR) 3.798, 95% confidence interval (CI) 1.400-10.467, P < 0.01], preoperative antibiotic administration (HR 4.434, 95% CI 1.591-14.775, P < 0.01), difficulties with intraoperative hemostasis (HR 16.298, 95% CI 2.986-110.677, P < 0.01), and higher serum creatinine levels (HR 7.465, 95% CI 1.616-39.576, P < 0.05) are significant predictors of postoperative hemorrhage after lower third molar extraction. Multivariate correlations were observed between risk factors including an elevated PT-INR value, preoperative antibiotic administration, and higher serum creatinine levels, and postoperative hemorrhage after lower third molar extraction in patients receiving warfarin therapy. Clinicians need to consider these risk factors for postoperative hemorrhage after the lower third molar extraction and monitor PT-INR in patients receiving warfarin therapy.

Prospective comparison of periprocedural coagulation markers among uninterrupted anticoagulants for atrial fibrillation ablation

BACKGROUND

The difference in coagulation state during the periprocedural period of atrial fibrillation (AF) ablation among patients with uninterrupted anticoagulation has not been fully elucidated.

OBJECTIVE

The purpose of this study was to compare periprocedural trends in coagulation markers among patients on uninterrupted anticoagulation for AF ablation.

METHODS

In total, 275 consecutive patients who underwent AF ablation were evaluated. These patients were divided according to the anticoagulant they received into the dabigatran group (DG) (n = 64); rivaroxaban group (RG) (n = 62); apixaban group (AG) (n = 60); edoxaban group (EG) (n = 59); and warfarin group (WG) (n = 30). The trends in coagulation markers and the rate of silent stroke (SS) confirmed by postoperative magnetic resonance imaging were evaluated.

RESULTS

The fibrin monomer complex (FMC) level on postoperative day 1 and the prothrombin fragment 1+2 (PF1+2) levels on the operative day and postoperative day 1 were higher in DG than in the other groups (P <.05, <.001, and <.001, respectively). The incidence of SS in DG (17%) was significantly higher than in RG (6%), AG (3%, EG (7%), or WG (4%) (P <.05). Dabigatran use independently predicted the occurrence of SS (odds ratio 4.12; 95% confidence interval 1.37-12.7; P <.05).

CONCLUSION

FMC and PF1+2 levels during the periprocedural period of AF ablation were higher in DG than in the other groups. Dabigatran use independently predicted the occurrence of SS.

Impact of Anticoagulation Intensity in Korean Patients with Atrial Fibrillation: Is It Different from Western Population?

BACKGROUND AND OBJECTIVES

Although anticoagulation with warfarin is recommended as an international normalized ratio (INR) of prothrombin time between 2.0 and 3.0 and mean time in the therapeutic range (TTR) ≥70%, little has been proven that universal criteria might be suitable in Korean atrial fibrillation (AF) patients.

METHODS

We analyzed 710 patients with non-valvular AF who took warfarin. INR value and clinical outcomes were assessed during 2-year follow-up. Intensity of anticoagulation was assessed as mean INR value and TTR according to target INR range. Primary net-clinical outcome was defined as the composite of new-onset stroke and major bleeding. Secondary net-clinical outcome was defined as the composite of new-onset stroke, major bleeding and death.

RESULTS

Thromboembolism was significantly decreased when mean INR was over 1.6. Major bleeding was significantly decreased when TTR was over 70% and mean INR was less than 2.6. Mean INR 1.6-2.6 significantly reduced thromboembolism (adjusted hazard ratio [HR], 0.40; 95% confidence interval [CI], 0.19-0.85), major bleeding (HR, 0.43; 95% CI, 0.23-0.81), primary (HR, 0.50; 95% CI, 0.29-0.84) and secondary (HR, 0.45; 95% CI, 0.28-0.74) net-clinical outcomes, whereas mean INR 2.0-3.0 did not. Simultaneous satisfaction of mean INR 1.6-2.6 and TTR ≥70% was associated with significant risk reduction of major bleeding, primary and secondary net-clinical outcomes.

CONCLUSIONS

Mean INR 1.6-2.6 was better than mean INR 2.0-3.0 for the prevention of thromboembolism and major bleeding. However, INR 1.6-2.6 and TTR ≥70% had similar clinical outcomes to INR 2.0-3.0 and TTR ≥70% in Korean patients with non-valvular AF.

Coagulation Factor Plasma Levels Following Administration of a 4-Factor Prothrombin Complex Concentrate for Rapid Vitamin K Antagonist Reversal in Japanese Patients

Background

Four-factor prothrombin complex concentrates (4F-PCCs) have been approved for urgent vitamin K antagonist reversal in Western countries for many years. Ethnicity and genetic variations between populations may influence the pharmacokinetic profile of 4F-PCC treatments.

Objective

To report plasma levels of vitamin K-dependent coagulation factors and proteins C and S in Japanese patients following administration of a 4F-PCC approved recently in Japan.

Methods

This was a subanalysis of a prospective, open-label, Phase IIIb study in Japanese patients requiring rapid vitamin K antagonist reversal owing to major bleeding (n = 6) or need for urgent surgery (n = 5). International normalized ratio and plasma levels of factors II, VII, IX, and X, and proteins C and S were measured before PCC infusion and at specific time points for the next 24 hours. Adverse events and serious adverse events were recorded up to Day 14 and 45, respectively.

Results

Rapid increases in plasma concentrations 30 minutes following 4F-PCC infusion were seen for all factors and proteins C and S, with median concentrations compared with baseline increasing by ≥100% and 70% in the bleeding and surgical groups, respectively. A concurrent decrease in international normalized ratio was observed. Plasma levels for each factor and protein remained within physiologic levels throughout the assessment period. No relationship between thromboembolic events and elevated plasma levels was identified.

Conclusions

Administration of 4F-PCC in Japanese patients receiving vitamin K antagonist anticoagulation therapy resulted in rapid and sustained increases in plasma levels and was well tolerated, indicating that this treatment is effective for the urgent reversal of vitamin K antagonist therapy in this population.

Comparison of direct oral anticoagulants and warfarin regarding midterm adverse events in patients with atrial fibrillation undergoing catheter ablation

BACKGROUND

Oral anticoagulants, including direct oral anticoagulants (DOACs), are usually required in atrial fibrillation (AF) patients who are at a high risk of thromboembolism (TE), even if they had undergone catheter ablation (CA). Although several studies have reported the safety and efficacy of DOACs around CA in AF patients, there are only limited data regarding the midterm incidence of TE and bleeding complications post-CA among AF patients treated with warfarin or DOACs.

METHODS

We studied 629 AF patients (mean age: 65.3 ± 10.3 years; 442 men) undergoing CA, to calculate the midterm incidence of TE and bleeding complications associated with warfarin or DOACs.

RESULTS

In total, 292 patients used warfarin and 337 used DOACs (dabigatran: 90 patients; rivaroxaban: 137; and apixaban: 110). At baseline, the CHA2DS2-VASc and HAS-BLED scores were similar between the 2 groups. During a median follow-up period of 7 months, no TE complications occurred. The warfarin group had a significantly higher bleeding event rate than did the DOACs group (all bleeding complications: 32 [11.0%] vs 15 [4.5%], respectively, P = .002). The rate of all bleeding complications was significantly higher in the warfarin group than in the DOACs group (10.1% vs 3.7%, respectively, at 10 months; P = .024). In Cox proportional hazards modeling, DOAC use was significantly associated with a decreased risk of bleeding (adjusted hazard ratio: 0.497; 95% confidence interval: 0.261-0.906, P = .022).

CONCLUSIONS

Direct oral anticoagulant use in AF patients undergoing CA may be associated with a similar risk of TE as warfarin but is associated with a lower risk of bleeding.

Incidence of silent cerebral infarctions after catheter ablation of atrial fibrillation utilizing the second-generation cryoballoon

Aims

Pulmonary vein (PV) isolation (PVI) utilizing a cryoballoon (CB) has become one of the standard therapeutic options for atrial fibrillation (AF). However, it connotes a potential risk of cerebral ischaemic events (CIEs). This study aimed to clarify the prevalence of CIEs after PVI using second-generation CBs assessed by magnetic resonance imaging (MRI) of the brain.

Methods and results

This prospective observational study consisted of 160 patients that underwent PVI with second-generation CBs for drug-refractory AF. Irrigated radiofrequency (RF) ablation for 'touch-up' procedures was utilized when conduction gaps between the left atrium (LA) and PVs were found after the CB application. Radiofrequency linear ablation was added in select patients. Cerebral MRI and neurological examinations were performed on the day following the ablation procedure. The MRI depicted micro-cerebral infarctions in 43 patients (26.9%, 1.49 lesions per case). All patients were free from symptomatic focal neurological deficits. Touch up ablation was required for the PVI establishment in 35 patients (21.9%). Linear ablation was performed in 59 patients (36.9%). Additional RF ablation within the LA was an independent risk of CIEs in the uni- and multivariate analyses. When the analyses were limited to patients who had undergone only CB ablation, CIEs were found in 12 of 66 patients (18.2%).

Conclusion

Pulmonary vein isolation utilizing second-generation CBs carries a negligible risk of symptomatic CIEs; however, it includes a comparable risk of asymptomatic CIEs as in the previous similar reports using the first-generation CB. Radiofrequency applications in addition to the CB within the LA were the only predictor of this adverse effect.

Sex disparities in acute myocardial infarction care and outcomes

AIM

We investigated sex-based and regional outcomes after contemporary percutaneous coronary intervention (PCI) with the Xience V stent in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

This patient level pooled analysis includes three multi-center, prospective post-market registries performed in the US, Japan, and China. A total of 1,938 patients treated with Xience V stents in the setting of AMI were enrolled. Compared to men, women had higher major adverse cardiac events (MACE) (14.1% vs. 9.8% P < 0.01, RR 1.4, 95% CI 1.1-1.4) and all-cause mortality (10% vs. 6.2% P < 0.01, RR 1.61, 95% CI 1.14-2.27) at one year, without any significant difference in device specific outcomes of target vessel failure (TVF). US patients compared to the patients from China and Japan had increased MACE (female: 18% vs. 7.1%, P = 0.0012, male: 15.7% vs. 4.1%, P < 0.0001). Multivariable analysis demonstrated that major bleeding was the strongest predictor of MACE (OR 10.51, 95%CI 4.01-27.50, P < 0.0001), MI (OR 4.26, 95%CI 1.37-13.29, P = 0.012), and all-cause death (OR 5.3, 95%CI 2.32-12.13, P < 0.0001).

CONCLUSION

Women with AMI who underwent PCI with XIENCE DES have higher all-cause mortality at one year in compared to men. Region based outcomes demonstrated increased MACE among US patients compared to the patients from China and Japan. After adjusting for differences in demographics, major bleeding, rather than female sex, predicted the higher observed all-cause mortality.

A survey of reasons for continuing warfarin therapy in the era of direct oral anticoagulants in Japanese patients with atrial fibrillation: the SELECT study

PURPOSE

Although warfarin has historically been the standard of care for preventing ischemic stroke in patients with nonvalvular atrial fibrillation (NVAF), the use of direct oral anticoagulants (DOACs) is rapidly increasing. In this study, we examined the demographic and clinical characteristics of patients continuing warfarin therapy and investigated reasons for warfarin continuation.

PATIENTS AND METHODS

Each study site consecutively registered 10 patients with NVAF who had been taking warfarin for at least 12 months. Demographic and clinical characteristics and international normalized ratio (INR) values were collected from medical records. Physicians responded to questionnaires exploring reasons for continuing warfarin therapy.

RESULTS

Overall, 313 patients treated with warfarin were registered at 33 sites. Mean ± SD age was 76.4±9.6 years; 62.9% of patients were male. The proportion of patients with INR values in the therapeutic range was 74.6% and 48.8% among patients aged ≥70 years and <70 years, respectively. Over half of the patients (51.4%) had been advised to switch from warfarin to DOACs; the primary physician-reported reason for this recommendation was superior safety and effectiveness. However, patients reported continuing warfarin because of the high price of DOACs (47.2%) and long-term positive experiences with warfarin (31.7%). The remaining 48.6% of patients with NVAF had never been counseled by their physicians about DOACs as an alternative to warfarin. For 76% of these patients, physicians favored warfarin for medical reasons, such as impaired renal function and controlled INR, but in the remaining patients, medical reasons for continuing warfarin were lacking.

CONCLUSION

Approximately half of the patients in this study were informed of warfarin alternatives primarily for improved efficacy and safety, but elected not to change regimens because of the high price of DOACs and long-term positive experiences with warfarin. In the remaining half, physician preference or specific patient characteristics prevented a change in therapy.

Stroke prevention in atrial fibrillation: An Asian perspective

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. In 2050, it is estimated that there will be 72 million AF patients in Asia, accounting for almost 2.9 million patients suffering from AF-associated stroke. Asian AF patients share similar risk factor profiles as non-Asians, except that more Asians have a history of previous stroke. Clinical challenges are evident in the field of stroke prevention in AF, amongst Asians. Existing stroke and bleeding risk scores have not been well-validated in Asians. Asians are prone to bleeding when treated with warfarin, and the optimal international normalised ratio (INR) for warfarin use is yet to be determined in Asians, though Asian physicians tend to keep it in a lower range (e.g. INR 1.6–2.6) for elderly patients despite limited evidence to justify this. In general, warfarin is ‘difficult’ to use in Asians due to higher risk of bleeding and higher stroke rate in Asians than in non-Asians, as shown in randomised controlled trials. Excess of bleeding was not found in Asians when novel oral anticoagulants (NOACs) were used. Besides, the superiority of NOACs to warfarin in reducing thromboembolism was maintained in Asians. Therefore NOACs are preferentially indicated in Asians in terms of both efficacy and safety. Also, some preliminary data suggest that Asian patients with AF might not be the same. Future prospective randomised trials are needed for the selection of NOACs according to different ethnic background.

Note: The review process for this manuscript was fully handled by Christian Weber, Editor in Chief.

Efficacy and safety of a 4-factor prothrombin complex concentrate for rapid vitamin K antagonist reversal in Japanese patients presenting with major bleeding or requiring urgent surgical or invasive procedures: a prospective, open-label, single-arm phase 3b study

Rapid vitamin K antagonist (VKA) reversal is required in patients experiencing major bleeding or requiring urgent surgery. Four-factor prothrombin complex concentrate (4F-PCC; Beriplex^®/Kcentra^®) was shown in two large randomized controlled, international phase 3b trials to be an effective alternative to plasma for urgent VKA reversal. In the present prospective, open-label, single-arm phase 3b trial, we evaluate the efficacy and safety of 4F-PCC in Japanese patients. Eleven patients [international normalized ratio (INR) ≥2] requiring rapid VKA reversal owing to major bleeding (n = 6) or before urgent surgical/invasive procedures (n = 5) were administered 4F-PCC dosed based on INR and weight. INR reduction (≤1.3 0.5 h postinfusion; primary endpoint) was achieved in 81.8% of patients (major bleeding, 83.3%; surgical/invasive procedures, 80.0%). Effective hemostasis (main secondary endpoint) was met in 60.0% (major bleeding) and 100% (surgical/invasive procedure) of evaluable patients. Adverse events (AEs) and serious AEs were reported in 90.9 and 45.5% of patients, respectively. Two AEs were considered treatment-related; thromboembolic events rated mild and not clinically relevant by investigators. There were no deaths, fluid overload events, or viral transmission cases. Consistent with the previous results, 4F-PCC may be an effective and well-tolerated treatment for rapid VKA reversal in Japanese patients experiencing major bleeding or requiring urgent surgical/invasive procedures.

Efficacy and Safety of Uninterrupted Low-Intensity Warfarin for Radiofrequency Catheter Ablation of Atrial Fibrillation in the Elderly

Background: No previous studies exist investigating the optimal intensity of uninterrupted anticoagulation with warfarin during radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) in the elderly. Objective: Evaluate the efficacy and safety of continuous low-intensity warfarin therapy throughout the periprocedural period of RFCA for AF in the elderly. Methods: This is a prospective randomized study. We enrolled AF patients (age ≥ 70 years) who underwent first-time RFCA for AF. Enrolled patients were randomized to group A and group B. The international normalized ratios before ablation were maintained at 1.5 to 2.0 and 2.0 to 2.5 in group A and B, respectively. Primary end points were periprocedural thromboembolic complications and major bleeding. Secondary end points included periprocedural asymptomatic cerebral emboli (ACE) and minor bleeding. Results: A total of 101 patients were enrolled in our study (group A: 52; group B: 49). Baseline characteristics were well balanced between the 2 groups. Only 1 patient suffered from stroke in group B. No major bleeding events occurred in either group. The incidence of new ACE lesions was comparable between the 2 groups (11.5% vs 8.2%, P = 0.82). Minor bleeding occurred in 1 of 52 (1.9%) patients in group A and in 5 of 49 (10.2%) patients in group B ( P = 0.10). Conclusions: Uninterrupted low-intensity warfarin for RFCA of AF might be as effective as standard-intensity warfarin in preventing periprocedural thromboembolic complications and might be associated with fewer bleeding events in the elderly.

Continuous use of low-dose warfarin for gastric endoscopic submucosal dissection: a prospective study

Background and study aims Patients who receive warfarin usually require heparin bridge therapy (HBT) to prevent thromboembolic events during endoscopic submucosal dissection (ESD); however, clinical evidence demonstrating the safety and efficacy of HBT during gastric ESD is limited. Conversely, warfarin can be continuously used as a substitute for HBT to endoscopic procedures which have a low risk of bleeding. This study aimed to clarify the safety and efficacy of continuous low-dose warfarin (LDW) for gastric ESD. Patients and methods This was a prospective observational study at a single institution. A total of 22 patients who received warfarin between December 2014 and January 2016 were enrolled. The patients were treated with gastric ESD with a low dose of warfarin ( ≤ 4 mg) at approximately 1.6 - 2.6 of the international normalized ratio (INR) levels. Furthermore, we analyzed a total of 23 patients with HBT who underwent gastric ESD between January 2011 and November 2014. Results The average of warfarin dose and the INR level on the day of gastric ESD in the continuous LDW group were 2.3 mg/day (range 0.5 - 4.0) and 1.87 (range 1.41 - 2.75), respectively. Two of the 22 patients (9.1 %) in the continuous LDW group and 5 of the 23 patients (21.7 %) in the HBT group had postoperative bleeding after gastric ESD. Although the postoperative bleeding rate in the continuous LDW group was lower than that in the HBT group, no significant difference was observed between the 2 groups (P = 0.414). Conclusions Gastric ESD with continuous LDW as a substitute for HBT was feasible and may be acceptable.

Quality of Anticoagulation with Warfarin in Korean Patients with Atrial Fibrillation and Prior Stroke: A Multicenter Retrospective Observational Study

Background and Purpose

The quality of anticoagulation is critical for ensuring the benefit of warfarin, but this has been less well studied in Korean ischemic stroke patients with atrial fibrillation (AF).

Methods

This study retrospectively analyzed the data of patients who had an AF-related ischemic stroke and were treated with long-term warfarin therapy in 16 Korean centers. The quality of warfarin therapy was primarily assessed by the time in therapeutic range [TTR; international normalized ratio (INR), 2.0–3.0] and additionally by the proportion of INR values within the therapeutic range.

Results

The long-term warfarin-treated cohort comprised 1,230 patients. They were aged 70.1±9.7 years (mean±SD), 42.5% were female, and their CHA₂DS₂-VASc score was 4.75±1.41. The TTR analysis included 33,941 INR measurements for 27,487 months: per patients, 27.6 (SD, 22.4) INR measurements for 22.4 (SD, 12.9) months. The mean TTR of individual patients was 49.1% (95% confidence interval, 47.9–50.3%), and the TTR quartiles were <34.5, 34.5–49.1, 49.1–64.5%, and >64.5%. None of the 16 centers achieved a mean TTR of >60%. Of all INR measurements, 44.6% were within the therapeutic range, 41.7% were <2.0, and 13.7% were >3.0.

Conclusions

In Korean ischemic stroke patients who had AF, the quality of warfarin therapy was low and might be inadequate to effectively prevent recurrent stroke or systemic embolism.

A new scoring system (DAIGA) for predicting bleeding complications in atrial fibrillation patients after drug-eluting stent implantation with triple antithrombotic therapy

BACKGROUND

No scoring system for evaluating the bleeding risk of atrial fibrillation (AF) patients after drug-eluting stent (DES) implantation with triple antithrombotic therapy (TAT) is available. We aimed to develop a new scoring system for predicting bleeding complications in AF patients after DES implantation with TAT.

METHODS AND RESULTS

Between April 2007 and April 2014, 227 AF patients undergoing DES implantation with TAT were enrolled. Bleeding incidence defined as Bleeding Academic Research Consortium criteria≥2 was investigated and predictors of bleeding complications were evaluated using multivariate analysis. Bleeding complications occurred in 58 patients (25.6%) during follow-up. Multivariate analysis revealed dual antiplatelet therapy (DAPT) continuation (OR 3.33, P=0.01), age>75 (OR 2.14, P=0.037), international normalized ratio>2.2 (OR 5.82, P<0.001), gastrointestinal ulcer history (OR 3.06, P=0.037), and anemia (OR 2.15, P=0.042) as predictors of major bleeding complications. A score was created using the weighted points proportional to the beta regression coefficient of each variable. The DAIGA score showed better predictive ability for bleeding complications than the HAS-BLED score (AUC: 0.79 vs. 0.62, P=0.0003). Bleeding incidence was well stratified: 17.8% in low-risk (scores 0-1), 55.5% in moderate-risk (2-3), and 83.0% in high-risk (4-7) patients (P<0.001).

CONCLUSIONS

This scoring system is useful for predicting bleeding complications and risk stratification of AF patients after DES implantation with TAT.

Development and Comparison of Warfarin Dosing Algorithms in Stroke Patients

PURPOSE

The genes for cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase complex subunit 1 (VKORC1) have been identified as important genetic determinants of warfarin dosing and have been studied. We developed warfarin algorithm for Korean patients with stroke and compared the accuracy of warfarin dose prediction algorithms based on the pharmacogenetics.

MATERIALS AND METHODS

A total of 101 patients on stable maintenance dose of warfarin were enrolled. Warfarin dosing algorithm was developed using multiple linear regression analysis. The performance of all the algorithms was characterized with coefficient of determination, determined by linear regression, and the mean of percent deviation was used to predict doses from the actual dose. In addition, we compared the performance of the algorithms using percentage of predicted dose falling within ±20% of clinically observed doses and dividing the patients into a low-dose group (≤3 mg/day), an intermediate-dose group (3-7 mg/day), and high-dose group (≥7 mg/day).

RESULTS

A new developed algorithms including the variables of age, body weight, and CYP2C9 and VKORC1 genotype. Our algorithm accounted for 51% of variation in the warfarin stable dose, and performed best in predicting dose within 20% of actual dose and intermediate-dose group.

CONCLUSION

Our warfarin dosing algorithm may be useful for Korean patients with stroke. Further studies to elucidate clinical utility of genotype-guided dosing and find the additional genetic association are necessary.

Cardiovascular Events of Electrical Cardioversion Under Optimal Anticoagulation in Atrial Fibrillation: The Multicenter Analysis

PURPOSE

Electric cardioversion has been successfully used in terminating symptomatic atrial fibrillation (AF). Nevertheless, largescale study about the acute cardiovascular events following electrical cardioversion of AF is lacking. This study was performed to evaluate the incidence, risk factors, and clinical consequences of acute cardiovascular events following electrical cardioversion of AF.

MATERIALS AND METHODS

The study enrolled 1100 AF patients (mean age 60±11 years) who received cardioversion at four tertiary hospitals. Hospitalizations for stroke/transient ischemic attack, major bleedings, and arrhythmic events during 30 days post electric cardioversion were assessed.

RESULTS

The mean duration of anticoagulation before cardioversion was 95.8±51.6 days. The mean International Normalized Ratio at the time of cardioversion was 2.4±0.9. The antiarrhythmic drugs at the time of cardioversion were class I (45%), amiodarone (40%), beta-blocker (53%), calcium-channel blocker (21%), and other medication (11%). The success rate of terminating AF via cardioversion was 87% (n=947). Following cardioversion, 5 strokes and 5 major bleedings occurred. The history of stroke/transient ischemic attack (OR 6.23, 95% CI 1.69-22.90) and heart failure (OR 6.40, 95% CI 1.77-23.14) were among predictors of thromboembolic or bleeding events. Eight patients were hospitalized for bradyarrhythmia. These patients were more likely to have had a lower heart rate prior to the procedure (p=0.045). Consequently, 3 of these patients were implanted with a permanent pacemaker.

CONCLUSION

Cardioversion appears as a safe procedure with a reasonably acceptable cardiovascular event rate. However, to prevent the cardiovascular events, several risk factors should be considered before cardioversion.

Intravenous Autologous Bone Marrow Mononuclear Cell Transplantation for Stroke: Phase1/2a Clinical Trial in a Homogeneous Group of Stroke Patients

The goal of this clinical trial was to assess the feasibility and safety of transplanting autologous bone marrow mononuclear cells into patients suffering severe embolic stroke. Major inclusion criteria included patients with cerebral embolism, age 20–75 years, National Institute of Health Stroke Scale (NIHSS) score displaying improvement of ≤5 points during the first 7 days after stroke, and NIHSS score of ≥10 on day 7 after stroke. Bone marrow aspiration (25 or 50 mL; N = 6 patients in each case) was performed 7–10 days poststroke, and bone marrow mononuclear cells were administrated intravenously. Mean total transplanted cell numbers were 2.5 × 10⁸ and 3.4 × 10⁸ cells in the lower and higher dose groups, respectively. No apparent adverse effects of administering bone marrow cells were observed. Compared with the lower dose, patients receiving the higher dose of bone marrow cells displayed a trend toward improved neurologic outcomes. Compared with 1 month after treatment, patients receiving cell therapy displayed a trend toward improved cerebral blood flow and metabolic rate of oxygen consumption 6 months after treatment. In comparison with historical controls, patients receiving cell therapy had significantly better neurologic outcomes. Our results indicated that intravenous transplantation of autologous bone marrow mononuclear cells is safe and feasible. Positive results and trends favoring neurologic recovery and improvement in cerebral blood flow and metabolism by cell therapy underscore the relevance of larger scale randomized controlled trials using this approach.

Differences in activated clotting time among uninterrupted anticoagulants during the periprocedural period of atrial fibrillation ablation

BACKGROUND

Close monitoring of intraoperative activated clotting time (ACT) is crucial to prevent complications during the periprocedural period of atrial fibrillation (AF) ablation. However, little is known about the ACT in patients receiving new oral anticoagulant agents (NOACs).

OBJECTIVE

The purpose of this study was to evaluate change in the ACT among anticoagulant agents used during the periprocedural period of AF ablation.

METHODS

We examined 869 consecutive patients who underwent AF ablation between April 2012 and August 2014 and received NOACs (n = 499), including dabigatran, rivaroxaban, and apixaban, or warfarin (n = 370) for uninterrupted periprocedural anticoagulation. Changes in intraprocedural ACT were investigated among the anticoagulant agents. Furthermore, the incidence of periprocedural events was estimated.

RESULTS

The average time in minutes required for achieving a target ACT >300 seconds was significantly longer in the dabigatran group (DG) and apixaban group (AG) than in the warfarin group (WG) and rivaroxaban group (RG) (60 and 70 minutes vs 8 and 9 minutes, respectively; P < .001). In addition, the proportion of patients who achieved the target ACT after initial heparin bolus was significantly lower in the DG and AG than in the WG and RG (36% and 26% vs 84% and 78%, respectively; P < .001). Furthermore, the incidence of periprocedural complications was equivalent among the groups.

CONCLUSION

The average time required to reach the target ACT was longer in the DG and AG than in the WG and RG.

Use of novel oral anticoagulants for the treatment of venous thromboembolism and its considerations in Asian patients

Parenteral anticoagulation followed by warfarin has been conventionally used for the treatment of venous thromboembolism (VTE). However, there are numerous troublesome characteristics of warfarin that prompted the development of novel oral anticoagulants (NOACs) for the treatment of VTE. Asians are reported to be at an increased risk of bleeding with warfarin, and while the reported incidence of VTE in Asians is lower than in Caucasians, the annual rate of VTE in Asia is rising along with the need for better oral anticoagulant options. Recently, several Phase III clinical trials with NOACs for the treatment and prevention of VTE recurrence have been published. For the treatment of VTE, the four NOACs - dabigatran, rivaroxaban, apixaban, and edoxaban - each showed comparable efficacy outcomes while resulting in better safety outcomes when compared with conventional treatment. In these trials, Asian patients had comparable efficacy and safety outcomes as other races, except in the edoxaban trial, in which the Asian subgroup had better safety profiles than other races, although further confirmation is necessary. For secondary prevention, dabigatran was compared with conventional treatment and showed similar efficacy and safety outcomes. When NOACs were compared with placebo for secondary prevention of VTE, they showed superior efficacy and increased bleeding except for apixaban, which showed comparable major bleeding and composite of major and clinically relevant nonmajor bleeding rates as placebo. No significant differences in the outcomes based on race were observed in the Asian subgroups for secondary prevention. Therefore, NOACs can be used with similar efficacy and at least similar or superior safety compared with conventional treatment in the treatment of VTE, and at no increased risk in Asian patients.

Different doses of recombinant tissue-type plasminogen activator for acute stroke in Chinese patients

BACKGROUND AND PURPOSE

The relationship between the dose of recombinant tissue-type plasminogen activator (r-tPA) and its safety/efficacy for ischemic stroke has not been well evaluated in the East Asian population. We assessed the safety/efficacy of different doses of r-tPA for acute ischemic stroke in Chinese patients.

METHODS

A total of 1004 eligible patients were classified according to the dose of r-tPA received for managing acute ischemic stroke: 0.9 mg/kg (n=422), 0.8 mg/kg (n=202), 0.7 mg/kg (n=199), and 0.6 mg/kg (n=181). The safety outcome was symptomatic intracerebral hemorrhage and death within 3 months. The efficacy outcome was good functional outcome (modified Rankin Scale ≤1) at 3 months.

RESULTS

There was a significant trend for symptomatic intracerebral hemorrhage with age (P=0.002). With multivariate logistic regression analysis, a dose of 0.9 mg/kg was a predictor of symptomatic intracerebral hemorrhage (P=0.0109), and a dose ≤0.65 mg/kg was a predictor of good functional outcome (P=0.0369). In patients aged 71 to 80 years, there was a significant trend of increasing symptomatic intracerebral hemorrhage (P=0.0130) and less good functional outcome (P=0.0179) with increasing doses of r-tPA. There was also a trend of increasing mortality (P=0.0971) at 3 months in these patients.

CONCLUSIONS

These results did not support the dose of 0.9 mg/kg of r-tPA being optimal for all patients in the East Asian population. In elderly patients (71-80 years), a lower dose of 0.6 mg/kg is associated with a better outcome. Confirmation of the results through randomized trial is required.

Anticoagulant and antiplatelet therapy in patients with atrial fibrillation undergoing percutaneous coronary intervention

The prevalence, intensity, safety, and efficacy of oral anticoagulation (OAC) in addition to dual antiplatelet therapy (DAPT) in "real-world" patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) have not yet been fully evaluated. In the Coronary REvascularization Demonstrating Outcome Study in Kyoto registry cohort-2, a total of 1,057 patients with AF (8.3%) were identified among 12,716 patients undergoing first PCI. Cumulative 5-year incidence of stroke was higher in patients with AF than in no-AF patients (12.8% vs 5.8%, p <0.0001). Although most patients with AF had CHADS2 score ≥2 (75.2%), only 506 patients (47.9%) received OAC with warfarin at hospital discharge. Cumulative 5-year incidence of stroke in the OAC group was not different from that in the no-OAC group (13.8% vs 11.8%, p = 0.49). Time in therapeutic range (TTR) was only 52.6% with an international normalized ratio of 1.6 to 2.6, and only 154 of 409 patients (37.7%) with international normalized ratio data had TTR ≥65%. Cumulative 5-year incidence of stroke in patients with TTR ≥65% was markedly lower than that in patients with TTR <65% (6.9% vs 15.1%, p = 0.01). In a 4-month landmark analysis in the OAC group, there was a trend for higher cumulative incidences of stroke and major bleeding in the on-DAPT (n = 286) than in the off-DAPT (n = 173) groups (15.1% vs 6.7%, p = 0.052 and 14.7% vs 8.7%, p = 0.10, respectively). In conclusion, OAC was underused and its intensity was mostly suboptimal in real-world patients with AF undergoing PCI, which lead to inadequate stroke prevention. Long-term DAPT in patients receiving OAC did not reduce stroke incidence.

Quality of vitamin K antagonist control and outcomes in atrial fibrillation patients: a meta-analysis and meta-regression

BACKGROUND

Atrial fibrillation (AF) patients frequently require anticoagulation with vitamin K antagonists (VKAs) to prevent thromboembolic events, but their use increases the risk of hemorrhage. We evaluated time spent in therapeutic range (TTR), proportion of international normalized ratio (INR) measurements in range (PINRR), adverse events in relation to INR, and predictors of INR control in AF patients using VKAs.

METHODS

We searched MEDLINE, CENTRAL and EMBASE (1990-June 2013) for studies of AF patients receiving adjusted-dose VKAs that reported INR control measures (TTR and PINRR) and/or reported an INR measurement coinciding with thromboembolic or hemorrhagic events. Random-effects meta-analyses and meta-regression were performed.

RESULTS

Ninety-five articles were included. Sixty-eight VKA-treated study groups reported measures of INR control, while 43 studies reported an INR around the time of the adverse event. Patients spent 61% (95% CI, 59-62%), 25% (95% CI, 23-27%) and 14% (95% CI, 13-15%) of their time within, below or above the therapeutic range. PINRR assessments were within, below, and above range 56% (95% CI, 53-59%), 26% (95% CI, 23-29%) and 13% (95% CI, 11-17%) of the time. Patients receiving VKA management in the community spent less TTR than those managed by anticoagulation clinics or in randomized trials. Patients newly receiving VKAs spent less TTR than those with prior VKA use. Patients in Europe/United Kingdom spent more TTR than patients in North America. Fifty-seven percent (95% CI, 50-64%) of thromboembolic events and 42% (95% CI, 35 - 51%) of hemorrhagic events occurred at an INR <2.0 and >3.0, respectively; while 56% (95% CI, 48-64%) of ischemic strokes and 45% of intracranial hemorrhages (95% CI, 29-63%) occurred at INRs <2.0 and >3.0, respectively.

CONCLUSIONS

Patients on VKAs for AF frequently have INRs outside the therapeutic range. While, thromboembolic and hemorrhagic events do occur patients with a therapeutic INR; patients with an INR <2.0 make up many of the cases of thromboembolism, while those >3.0 make up many of the cases of hemorrhage. Managing anticoagulation outside of a clinical trial or anticoagulation clinic is associated with poorer INR control, as is, the initiation of therapy in the VKA-naïve. Patients in Europe/UK have better INR control than those in North America.

Measures of vitamin K antagonist control reported in atrial fibrillation and venous thromboembolism studies: a systematic review

OBJECTIVE

To aid trialists, systematic reviewers and others, we evaluated the degree of standardisation of control measure reporting that has occurred in atrial fibrillation (AF) and venous thromboembolism (VTE) studies since 2000; and attempted to determine whether the prior recommendation of reporting ≥2 measures per study has been employed.

DESIGN

Systematic review.

SEARCH STRATEGY

We searched bibliographic databases (2000 to June 2013) to identify AF and VTE studies evaluating dose-adjusted vitamin K antagonists (VKAs) and reporting ≥1 control measure. The types of measures reported, proportion of studies reporting ≥2 measures and mean (±SD) number of measures per study were determined for all studies and compared between subgroups.

DATA EXTRACTION

Through the use of a standardised data extraction tool, we independently extracted all data, with disagreements resolved by a separate investigator.

RESULTS

148 studies were included, 57% of which reported ≥2 control measures (mean/study=2.13±1.36). The proportion of time spent in the target international normalised ratio range (TTR) was most commonly reported (79%), and was frequently accompanied by time above/below range (52%). AF studies more frequently reported ≥2 control measures compared with VTE studies (63% vs 37%; p=0.004), and reported a greater number of measures per study (mean=2.36 vs 1.53; p<0.001). Observational studies were more likely to provide ≥2 measures compared with randomised trials (76% vs 33%; p<0.001) and report a greater number of measures (mean=2.58 vs 1.63; p<0.001). More recent studies (2004-2013) reported ≥2 measures more often than older (2000-2003) studies (59% vs 35%; p=0.05) and reported more measures per study (mean=2.23 vs 1.48; p=0.02).

CONCLUSIONS

While TTR was often utilised, studies reported ≥2 measures of VKA control only about half of the time and lacked consistency in the types of measures reported. A trend towards studies reporting greater numbers of VKA control measures over time was observed over our review time horizon, particularly, with AF and observational studies.

Influence of sex on risk of bleeding in anticoagulated patients: a systematic review and meta-analysis

BACKGROUND

The risk of bleeding on anticoagulation varies between patients. It is uncertain whether sex influences this risk.

OBJECTIVES

To determine if the risk of major bleeding differs between men and women receiving anticoagulation for atrial fibrillation or venous thromboembolism(VTE).

METHODS

We searched MEDLINE, EMBASE, and Cochrane databases, and relevant conference proceedings, until February 2013. We included randomized controlled trials and prospective cohort studies of patients on therapeutic anticoagulation for atrial fibrillation or VTE. Two reviewers independently extracted data. The relative risk of bleeding in men compared to women was pooled using a random-effects model.

RESULTS

Forty-two studies including 94 293 patients were eligible; 78 044 patients (83%) had atrial fibrillation; 16 156 patients (17%) had VTE; 37 250 patients were women (40%); and there were 4147 major bleeds. The relative risk of major bleeding for men vs. women was 1.02(95% CI 0.95–1.10; P = 0.27 for heterogeniety). The relative risk was 1.02 (95% CI 0.95–1.09) in patients with atrial fibrillation and 0.80 (95% CI 0.65–0.98) in patients with VTE (P = 0.03 for subgroup effect). Type of anticoagulant,intensity of anticoagulation, and whether patients began or were already established on anticoagulants at enrollment did not influence the relative risk of major bleeding in men compared to women.

CONCLUSIONS

The risk of major bleeding on anticoagulation appears to be the same in men and women, particularly if patients have atrial fibrillation. This finding is less certain for patients with VTE, in whom the risk of bleeding may be marginally lower in men compared to in women.