Validation of the SAMe-TT2R2 score in a nationwide population of nonvalvular atrial fibrillation patients on vitamin K antagonists

Modified application of SAMe-TT2R2 scoring system in Asian patients with atrial fibrillation for the selection of oral anticoagulants

BACKGROUND/AIMS

The SAMe-TT2R2 score is used for assessing anticoagulation control (AC) quality with warfarin. However, it is hard to apply SAMe-TT2R2 score in Asian patients with atrial fibrillation (AF), because it has not been proven in those populations. This study aimed to validate the SAMe-TT2R2 score in Asian patients with AF and suggest a modified SAMe- TT2R2 score for this population.

METHODS

We analyzed 710 Korean patients with AF who were using warfarin. The AC quality was assessed as the mean time in therapeutic range (TTR). Each component of SAMe-TT2R2 score was evaluated for the relationship with AC. Further clinical factors that predict AC were analyzed. Identified factors were re-assorted and constructed as SA2Me-TTR scoring system.

RESULTS

Of the components of the SAMe-TT2R2 score, female, age, and rhythm control were associated with AC. Heart failure and renal insufficiency were newly identified factors associated with AC. The modified SA2Me-TTR score was reconstructed with the relevant risk factors (S, female gender, 1 point; A, age < 60 yr, 2 points; Me, medical history of heart failure, 1 point; T, treatment for rhythm control, 1 point; T, history of stroke or transient ischemic attack, 1 point; R, renal insufficiency, 1 point). The modified SA2Me-TTR score demonstrated an excellent relationship with the grading of AC. The modified SA2Me-TTR score ≤ 1 identified patients with good AC (hazard ratio 2.46, 95% CI 1.75-3.47).

CONCLUSION

The modified SA2Me-TTR score was useful for guiding oral anticoagulants selection in Asian patients with AF.

SAMe-TT2R2 Score to Predict Time in Therapeutic Range of Vitamin K Antagonists in Asian and Non-Asian patients: A Systematic Review and Meta-analysis

BACKGROUND

Sex, age, medical history, treatment, tobacco use, and race (SAMe-TT2R2) score helps detect patients at risk of suboptimal anticoagulation control. A score above two suggests poor control; however, non-Caucasian status being assigned two points might hinder the recognition of poor control in patients of other races.

OBJECTIVE

To evaluate the SAMe-TT2R2 score's ability to predict poor anticoagulation control [defined as time in therapeutic range (TTR) < 60-70%] in Asian and non-Asian populations on vitamin K antagonists (VKAs).

METHODS

We searched PubMed, Cochrane Library, Scopus, SpringerLink, and Web of Science using the keyword "SAMe-TT2R2." Articles published before April 2022 were screened. We gathered mean TTR and diagnostic accuracy data for different SAMe-TT2R2 thresholds and conducted meta-analyses using random-effects models.

RESULTS

A total of 30 studies were included (N = 36,690). The overall mean TTR differences were - 4.88 and - 6.41 for the cutoffs of ≥ 3 and ≥ 4, respectively. For non-Asian patients, the mean TTR differences were - 3.86, - 5.12, and - 8.09 for the cutoffs ≥ 2, ≥ 3, and ≥ 4, respectively. For Asian patients, the mean TTR differences were - 3.99 and - 4.07 for the cut-offs ≥ 3 and ≥ 4, respectively. The highest positive likelihood ratio (LR+) for the Asian subgroup was 1.17 [95% confidence interval (CI): 1.06-1.28; I2 = 0%, p heterogeneity = 0.500] at cutoff ≥ 4 and for the non-Asian subgroup, at cut-off ≥ 3, the LR+ was 1.24 (95% CI 1.14-1.34; I2 = 0% p heterogeneity = 0.455). The lowest LR- was found at a lower cutoff for both races (at cutoff ≥ 3 and ≥ 2 for Asian and non-Asian subgroups, respectively). The pooled results of other accuracy parameters were modest at all cutoffs, except for the sensitivity at cutoff ≥ 3 in the Asian subgroup (83.05%).

CONCLUSION

Our study results suggest that a higher SAMe-TT2R2 score resulted in a greater reduction of TTR among Asian and all races. The accuracy parameters showed the highest sensitivity for poor TTR at the SAMe-TT2R2 cutoff of ≥ 3 for Asian patients. However, the ability to identify patients likely to have poor TTR was limited. Further research is needed to enhance the risk assessment for poor anticoagulation control with VKAs.

REGISTRATION

The protocol of this systematic review was registered in the International Prospective Register of Scientific Reviews: PROSPERO, registration number CRD42021291865.

Use of SAMe-TT2R2 in a racially diverse anticoagulation clinic: prediction of optimal anticoagulation

The SAMe-TT₂R₂ score predicts optimal long-term oral Vitamin K Antagonist (VKA) anticoagulation for homogenous Caucasian and homogenous Asian populations for non-valvular atrial fibrillation but at different score thresholds. The score that predicts optimal VKA anticoagulation in significantly diverse populations for multiple indications for systemic anticoagulation has not been reported. We determined whether optimal VKA anticoagulation is predicted by SAMe-TT₂R₂ score in a diverse inner-city population for non-valvular atrial fibrillation (NVAF), unprovoked venous and pulmonary thromboembolic disease (VTE), mechanical prosthetic heart valves and all other indications. All patients on long term VKA's that attended an inner-city anticoagulation clinic between February 2016 and October 2017 were included in this study. Eligible patients were grouped according to oral anticoagulation indication: (1) NVAF, (2) VTE, (3) prosthetic valves and (4) other indications. Each patient's SAMe-TT₂R₂ score and percent time of INR in the therapeutic range (TTR) was calculated with optimal international normalized ratio (INR) control defined as TTR ≥ 65%. The correlation between SAMe-TT₂R₂ score and TTR was determined by logistic regression for each oral anticoagulant indication. Receiver operating characteristic curves were then used to identify the best cutoff for prediction of ≥ 65% TTR. Of 316 patients meeting study criteria, 54% were non-Caucasian and there was a significant negative correlation between the SAMe-TT₂R₂ score and TTR (coefficient - 0.35, P < 0.0001) for all patients. A SAMe-TT₂R₂ score < 4 was identified as the best threshold for predicting optimal TTR (Youden's J-statistics = 0.238) with accuracy and positive likelihood ratio of 63.4% and 1.73, respectively. The SAMe-TT₂R₂ score predicts optimal VKA anticoagulation for systemic anticoagulation for multiple indications in a diverse urban population at a higher score than the original report for non-valvular atrial fibrillation of a cohort where < 10% non-Caucasians.

Evaluation of the Validity of SAMe-TT2R2 Score in a Cohort of Venous Thromboembolism Patients Treated With Warfarin

Low SAMe-TT2R2 score of <2 was validated as a predictor of optimum anticoagulation control, reflected by mean time in therapeutic range (TTR) above 65% to 70%, among warfarin-treated atrial fibrillation patients. This study aimed to validate the ability of SAMe-TT2R2 score and its individual components in predicting anticoagulation control (mean TTR and clinical events) among a cohort of venous thromboembolism (VTE) patients in Qatar. A total of 295 patients were retrospectively evaluated. There was a trend toward statistical significance in mean TTR between low (<2) and high (≥ 2) SAMe-TT2R2 score groups (P = .05), a difference that was not sustained when a cutoff of 3 was used (ie, a score of 3 or more). Patients with poor INR control (TTR <70%) were numerically less likely to have SAMe-TT2R2 score of <2 compared with those with good INR control, though the difference was not statistically significant (16.7% vs 83.3%, respectively, P = .4). No thromboembolic events were reported, and no association was found between the score and risk of bleeding. Non-Caucasian origin was the only significant predictor of good anticoagulation in the studied cohort. In conclusion, SAMe-TT2R2 score could not predict quality of anticoagulation control in a cohort of VTE patients treated with warfarin in Qatar. Contribution of other clinical factors and whether a different scoring may yield better prediction of anticoagulation control remains to be tested.

The 2018 European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation

The current manuscript is the second update of the original Practical Guide, published in 2013 [Heidbuchel et al. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace 2013;15:625-651; Heidbuchel et al. Updated European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist anticoagulants in patients with non-valvular atrial fibrillation. Europace 2015;17:1467-1507]. Non-vitamin K antagonist oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with atrial fibrillation (AF) and have emerged as the preferred choice, particularly in patients newly started on anticoagulation. Both physicians and patients are becoming more accustomed to the use of these drugs in clinical practice. However, many unresolved questions on how to optimally use these agents in specific clinical situations remain. The European Heart Rhythm Association (EHRA) set out to coordinate a unified way of informing physicians on the use of the different NOACs. A writing group identified 20 topics of concrete clinical scenarios for which practical answers were formulated, based on available evidence. The 20 topics are as follows i.e., (1) Eligibility for NOACs; (2) Practical start-up and follow-up scheme for patients on NOACs; (3) Ensuring adherence to prescribed oral anticoagulant intake; (4) Switching between anticoagulant regimens; (5) Pharmacokinetics and drug-drug interactions of NOACs; (6) NOACs in patients with chronic kidney or advanced liver disease; (7) How to measure the anticoagulant effect of NOACs; (8) NOAC plasma level measurement: rare indications, precautions, and potential pitfalls; (9) How to deal with dosing errors; (10) What to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a potential risk of bleeding; (11) Management of bleeding under NOAC therapy; (12) Patients undergoing a planned invasive procedure, surgery or ablation; (13) Patients requiring an urgent surgical intervention; (14) Patients with AF and coronary artery disease; (15) Avoiding confusion with NOAC dosing across indications; (16) Cardioversion in a NOAC-treated patient; (17) AF patients presenting with acute stroke while on NOACs; (18) NOACs in special situations; (19) Anticoagulation in AF patients with a malignancy; and (20) Optimizing dose adjustments of VKA. Additional information and downloads of the text and anticoagulation cards in different languages can be found on an EHRA website (www.NOACforAF.eu).

Management of asymptomatic arrhythmias: a European Heart Rhythm Association (EHRA) consensus document, endorsed by the Heart Failure Association (HFA), Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), Cardiac Arrhythmia Society of Southern Africa (CASSA), and Latin America Heart Rhythm Society (LAHRS)

Asymptomatic arrhythmias are frequently encountered in clinical practice. Although studies specifically dedicated to these asymptomatic arrhythmias are lacking, many arrhythmias still require proper diagnostic and prognostic evaluation and treatment to avoid severe consequences, such as stroke or systemic emboli, heart failure, or sudden cardiac death. The present document reviews the evidence, where available, and attempts to reach a consensus, where evidence is insufficient or conflicting.

Low Performance of a Clinical-Genetic Model in the Estimation of Time in Therapeutic Range in Acenocoumarol-Adherent Patients with Nonvalvular Atrial Fibrillation: The Quality of Anticoagulation Challenge

BACKGROUND

Anticoagulation with vitamin K antagonists continues to be a challenging task given the difficulty of achieving a correct time in therapeutic range (TTR). The SAMeTT2R2 score has been proposed to identify patients that will be good responders. In this study we aimed to analyse clinical and genetic factors involved in a correct level of anticoagulation in patients with atrial fibrillation and thereby potentially improve the diagnostic performance of SAMeTT2R2 score.

METHODS

We prospectively included 212 consecutive patients with nonvalvular atrial fibrillation under treatment with acenocoumarol for at least 6 months that were attended in a cardiology outpatient clinic and were categorized as adherent to medication. We carried out a multivariate regression analysis to detect the independent predictive factors of good control. In all patients VKORC1, CYP2C9⁎2, CYP2C9⁎3, and MIR133A2 genotyping was performed.

RESULTS

A total of 128 (60.4%) patients presented TTR <70% (average TTR = 63.2). We identified body mass index (OR 0.94, 95%CI 0.89-0.99, p=0.032) and regular vitamin K intake (OR 0.53, 95%CI 0.28-0.99, p= 0.046) as independent predictors of poor anticoagulation control. The discriminatory power of a clinical-genetic model derived from our cohort was significantly better compared to the SAMeTT2R2 score (C-statistic 0.658 versus 0.524, p<0.001).

CONCLUSIONS

In our study the SAMeTT2R2 score revealed a poor ability in the prediction of TTR. Besides SAMeTT2R2, body mass index and possibly vitamin K intake should be taken into account when deciding the optimal anticoagulation strategy. The information provided by the identified genotypes was marginal.

Clinical usefulness of the SAMe-TT2R2 score: A systematic review and simulation meta-analysis

Background

Vitamin K antagonist (VKA) therapy is safer and more effective when patients have a high time within the therapeutic range and low international normalised ratio variability. The SAMe-TT₂R₂ score aims to identify those at risk for poor VKA control.

Objectives

To evaluate the predictive value and clinical usefulness of the SAMe-TT₂R₂ score to identify those at risk for poor VKA control.

Methods

We performed a systematic review in MEDLINE and Embase for original research papers assessing the SAMe-TT₂R₂’s relation to poor TTR. We performed a meta-analysis where scores ≥ 2 and ≥ 3 predicting TTR < 70%. When studies evaluated other cutoffs for TTR or SAMe-TT₂R₂, they were harmonised by multiple simulations with patient characteristics from the individual studies, if the data were available.

Results

16 studies were identified and used in the meta-analysis: 4 and 2 times directly, 8 and 8 times harmonised for scores ≥ 2 and ≥ 3, respectively (not all studies provided information about both cutoffs). The sensitivities and specificities were too heterogeneous to pool. The positive likelihood ratios were 1.25 (1.14-1.38) for a score ≥ 2, and 1.24 (1.09-1.40) for a score ≥ 3; the negative ones were 0.87 (0.82-0.93) and 0.96 (0.91-1.02), respectively. This shows that the post-test probabilities hardly differ from the prior probability (prevalence).

Conclusion

The SAMe-TT₂R₂ score does predict low TTR, but the effect is small. Its effect on individual patients is too limited to be clinically useful.

The SAME-TT2R2 score predicts the quality of anticoagulation control in patients with acute VTE

The SAMe-TT2R2 score has recently been proposed to predict the quality of vitamin K antagonist (VKA) anticoagulation control in patients with atrial fibrillation. We aimed at investigating whether the score is effective also in patients with venous thromboembolism (VTE). Patients included in the START-Register because started VKA therapy for a recent VTE episode and with > 3 months follow-up were analyzed. The score was calculated using the baseline patient’s characteristics present in the electronic database of the registry, where all INR results were also available and analysed to calculate the time in therapeutic range (TTR). A total of 1308 patients (53.4 % female, median age 68 years) were analysed. During 998 patient-years followup, the median TTR was 63 %. The maximum score in the patients was 4, with 70 % of them having 0–1. INR controls within range (2.0–3.0) were significantly less prevalent in patients with score ≥ 2 vs 0–1 score (58.5 ± 20 % vs 61.5 ± 19 %, respectively, p = 0.046). Patients with score ≥ 2 vs 0–1 had a highly significant lower TTR during the first 3 months of therapy (53 ± 26 % and 61 ± 26 %, respectively; p=0.0001), difference mainly due to more time spent below 2.0 INR (38 ± 28 % vs 31.3 ± 26.7 %, respectively; p=0.0001). In conclusion, the study proved, for the first time, that the SAMe-TT2R2 score is useful to predict among VTE patients those who will have good (score 0–1) or less good (score ≥ 2) VKA anticoagulation control. The score can help decision-making in everyday clinical practice, especially when choosing between VKA and non-vitamin K antagonists direct anticoagulants.

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

Use of the SAMe-TT2R2 score to predict anticoagulation control in atrial fibrillation and venous thromboembolism patients receiving vitamin K antagonists: A review

Identifying patients who are likely to achieve and maintain a therapeutic international normalized ratio when prescribed a vitamin K antagonist for stroke prevention in atrial fibrillation (AF) and venous thromboembolism (VTE) is challenging. The SAMe-TT₂R₂ score was developed on the basis of common clinical factors that can highlight patients who may be unable to achieve and maintain good anticoagulation control and for whom a "trial of warfarin" would be inadvisable. This review summarizes the main published prospective and retrospective studies that have validated the SAMe-TT₂R₂ score in patients with AF and VTE treated with a vitamin K antagonist and how the SAMe-TT₂R₂ score could aid clinical decision making; 19 studies were included. Taken together, validation studies suggest that the SAMe-TT₂R₂ score is able to predict good or poor anticoagulation control in patients with AF and VTE, although data on patients with VTE are limited (3 studies). The available evidence suggests that the SAMe-TT₂R₂ score may be a useful tool to aid clinical decision making for oral anticoagulants in patients with AF and VTE.

Stroke prevention in atrial fibrillation: Past, present and future

Concepts and our approaches to stroke prevention in atrial fibrillation (AF) have changed markedly over the last decade. There has been an evolution over the approach to stroke and bleeding risk assessment, as well as new treatment options. An increasing awareness of AF has led to calls to improve the detection of and population screening for AF. Stroke and bleeding risk assessment continues to evolve, and the ongoing debate on balance between simplicity and practicality, against precision medicine will continue. In this review article, we provide an overview of past, present and the (likely) future concepts and approaches to stroke prevention in AF. We propose three simple steps (the Birmingham ‘3-step’) that offers a practical management pathway to help streamline and simplify decision-making for stroke prevention in patients with AF.

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

[Prevalence of oral anticoagulation and quality of its management in primary healthcare: A study by the Health Sentinel Network of the Region of Valencia (Spain)]

OBJECTIVE

To estimate the prevalence of patients with oral anticoagulant therapy (OAT) in the Region of Valencia and to evaluate the quality of management of OAT with vitaminK antagonists (VKA) carried out in primary healthcare.

DESIGN

Observational cross-sectional study conducted through the Health Sentinel Network of the Region of Valencia, which includes a survey and the retrospective analysis of OAT monitoring.

SETTING

Primary healthcare, Region of Valencia, Spain.

SUBJECTS

All patients aged 18years or older on OAT who consulted during the year 2014. The population covered by the 59 doctors of the Health Sentinel Network constitutes 2.2% of the adult population of the Region of Valencia, and it is representative of it.

KEY MEASUREMENTS

Demographic, socioeconomic and health data as well as information concerning OAT. Quality of OAT management with VKA was assessed by means of the percentage of time in therapeutic range (TTR), computed using the Rosendaal method.

RESULTS

A total of 1,144 patients were recorded (mean age 74.5±11 years; 49.7% women). Prevalence of OAT in the Region of Valencia is 1.3 cases per 100 population. The characteristic profile of these patients is an old person, with several comorbidities and a low level of education, who lives accompanied. Atrial fibrillation is the most common indication. 82.8% of patients on OAT with VKA were monitored in primary healthcare. The average TTR was 65.0%, and 53.9% of patients had a TTR ≥65%. Among inadequately controlled patients, 74.4% were perceived as well-controlled by their primary care doctor.

CONCLUSIONS

Prevalence of OAT is high, and it is expected to increase. The degree of control achieved meets the generally accepted quality standard (mean TTR ≥65%), and it is comparable to that observed in other national and international studies. However, there is wide scope for improvement. It is crucial to optimize the management of this therapy in the most effective and cost-effective way. Among other measures, access of physicians to their patients' clinical information should be improved.

Importance of time in therapeutic range on bleeding risk prediction using clinical risk scores in patients with atrial fibrillation

Bleeding risk with vitamin K antagonists (VKAs) is closely related to the quality of anticoagulation in atrial fibrillation (AF) patients, reflected by time in therapeutic range (TTR). Here we compared the discrimination performance of different bleeding risk scores and investigated if adding TTR would improve their predictive value and clinical usefulness. We included 1361 AF patients stables on VKA for at least 6 months. Bleeding risk was assessed by the HAS-BLED, ATRIA, ORBIT and HEMORR₂HAGES scores. Major bleeding events were recorded after a median of 6.5 years follow-up. In this period 250 patients suffered major bleeds. Comparison of receiver operating characteristic (ROC) curves demonstrated that HAS-BLED had the best discrimination performance, but adding the ‘labile INR’ criteria (i.e. TTR <65%) to ATRIA, ORBIT and HEMORR₂HAGES increased their ability of discrimination and predictive value, with significant improvements in reclassification and discriminatory performance. Decision curve analyses (DCA) showed improvements of the clinical usefulness and a net benefit of the modified risk scores. In summary, in AF patients taking VKAs, the HAS-BLED score had the best predictive ability. Adding ‘labile INR’ to ATRIA, ORBIT and HEMORR₂HAGES improved their predictive value for major bleeding leading to improved clinical usefulness compared to the original scores.

Anticoagulation Control in Warfarin-Treated Patients Undergoing Cardioversion of Atrial Fibrillation (from the Edoxaban Versus Enoxaparin-Warfarin in Patients Undergoing Cardioversion of Atrial Fibrillation Trial)

In the Edoxaban Versus Enoxaparin-Warfarin in Patients Undergoing Cardioversion of Atrial Fibrillation (ENSURE-AF) study (NCT 02072434), edoxaban was compared with enoxaparin-warfarin in 2,199 patients undergoing electrical cardioversion of nonvalvular atrial fibrillation (AF). In this multicenter prospective randomized open blinded end-point trial, we analyzed patients randomized to enoxaparin-warfarin. We determined time to achieve therapeutic range (TtTR); time in therapeutic range (TiTR); their clinical determinants; relation to sex, age, medical history, treatment, tobacco use, race risk (SAMe-TT₂R₂) score; and impact on primary end points (composite of stroke, systemic embolic event[SEE], myocardial infarction [MI], and cardiovascular death [CVD] and composite of major + clinically relevant nonmajor bleeding). Among 1,104 patients randomized to enoxaparin-warfarin, 27% were naïve to oral anticoagulants. Mean age was 64.2 ± 11 years and mean congestive heart failure, hypertension, age ≥75 (doubled), diabetes mellitus, prior stroke or transient ischemic attack (doubled), vascular disease, age 65-74, female (CHA₂DS₂-VASc) score was 2.6. Mean TtTR was 7.7 days (median 7 days) and mean TiTR after reaching an international normalized ratio of 2.0 to 3.0 was 71%. In 695 patients who had an INR <2.0 before the first dose and who reached an INR ≥2.0, 436 had a SAMe-TT₂R₂ score ≤2 and 259 had a score >2. On multivariate regression, an independent predictor of extended TtTR was creatinine clearance (p = 0.02). TtTR was marginally related to stroke/SEE/MI/CVD (p = 0.06; odds ratio  0.23, 95% confidence interval 0.02 to 1.17) but not to any bleeding. Independent predictors of TiTR were previous vitamin K antagonist experience (p<0.01) and low hypertension, abnormal renal or liver function, stroke, bleeding, labile INRs, age >65, concomitant drugs or alcohol (HAS-BLED) score (p = 0.02). TiTR was related to any bleeding (p = 0.02; odds ratio  0.39, 95% confidence interval 0.16 to 0.88), but not stroke/SEE/MI/CVD. In this cohort of warfarin users with a high TiTR no difference was seen between TtTR and TiTR in relation to SAMe-TT₂R₂ score. In conclusion, even in this short-term study, TiTR was significantly related to bleeding events.

Influence of renal function on anticoagulation control in patients with non-valvular atrial fibrillation taking vitamin K antagonists

BACKGROUND AND PURPOSE

Chronic kidney disease (CKD) has been related to poor anticoagulation control and an increased risk of bleeding. This study aims to evaluate the association between impaired renal function (eGFR <60 mL/min/1.73 m² ) and anticoagulation control in patients with non-valvular atrial fibrillation (AF) on vitamin K antagonists (VKA) therapy. We also assessed whether the predictive value of the SAMe-TT₂ R₂ score prevailed for subgroups both with and without CKD.

METHODS

This is an ancillary analysis of 1381 patients from the PAULA study, which was a cross-sectional, retrospective and nationwide multicenter study.

RESULTS

A total of 370 patients had eGFR <60 mL/min/1.73 m² . Anticoagulation control levels progressively worsened across each stage of CKD. Multiple linear regression analysis showed CKD as an independent predictor of time in therapeutic range (TTR). In the subgroup of patients with preserved renal function, female sex, diet affecting INR, polypharmacy and amiodarone were associated with poorer TTR. The SAMe-TT₂ R₂ score had a significant but modest predictive value for TTR<65% (AUC, area under the curve 0.558, P = .002). In the subgroup of patients with CKD, the SAMe-TT₂ R₂ (>2 points) showed no significant predictive capacity for TTR (AUC 0.528, P = .354). The average TTR was similar for both sexes (P = .255), but with a higher percentage of males subjects with TTR ≥65% (P = .013).

CONCLUSION

Chronic kidney disease is associated with poor anticoagulation control in patients with non-valvular AF taking VKA. The SAMe-TT₂ R₂ score was not predictive of poor TTR in the subgroup with CKD, although a modest predictive value for poor TTR was found in those without CKD.

Integrating genotypes in the SAMe-TT2R2 score for the prediction of anticoagulation control in Chinese patients with atrial fibrillation on warfarin

INTRODUCTION

The SAMe-TT₂R₂ score has been proposed to predict whether patients with atrial fibrillation (AF) would be well anti-coagulated with warfarin or not. However, it might over-estimate the number of patients under suboptimal warfarin treatment in non-Caucasians. This study was designed to modify the SAMe-TT₂R₂ score with genotypes and validate it in Chinese AF patients treated with warfarin.

MATERIAL AND METHODS

Consented Chinese-Han patients (n=510) with AF under the treatment of warfarin for at least 3months were randomly divided into a derivation (n=310) and a validation cohort (n=200). For each patient, CYP2C9*3 and VKORC1 -1639 A/G genotyping was performed, and the time in therapeutic range (TTR) was calculated over this period.

RESULTS

The modified SAMe-TT₂R₂ score was established by adding "warfarin genotype bins" to replace "the non-white race" variable. In the validation cohort, the discrimination performance of the modified score for good anticoagulation control (TTR≥70%) was significantly improved (c- index increased from 0.60 to 0.67). Significantly increased risks of major bleedings (HR: 4.91; 95% CI: 1.03-23.37; adjusted p=0.04) and all bleedings (HR: 1.93; 95% CI: 1.14-3.25; adjusted p=0.01) were found in patients with modified scores ≥2, as compared with patients with modified scores of 0-1.

CONCLUSIONS

The modified SAMe-TT₂R₂ score could improve the ability for the identification of good anticoagulation control, and the prediction of major bleeding events in Chinese patients with AF treated by warfarin.

Hypertension and Atrial Fibrillation: An Intimate Association of Epidemiology, Pathophysiology, and Outcomes

Atrial fibrillation (AF) is the most prevalent sustained arrhythmia found in clinical practice. AF rarely exists as a single entity but rather as part of a diverse clinical spectrum of cardiovascular diseases, related to structural and electrical remodeling within the left atrium, leading to AF onset, perpetuation, and progression. Due to the high overall prevalence within the AF population arterial hypertension plays a significant role in the pathogenesis of AF and its complications. Fibroblast proliferation, apoptosis of cardiomyocytes, gap junction remodeling, accumulation of collagen both in atrial and ventricular myocardium all accompany ageing-related structural remodeling with impact on electrical activity. The presence of hypertension also stimulates oxidative stress, systemic inflammation, rennin-angiotensin-aldosterone and sympathetic activation, which further drives the remodeling process in AF. Importantly, both hypertension and AF independently increase the risk of cardiovascular and cerebrovascular events, e.g., stroke and myocardial infarction. Given that both AF and hypertension often present with limited on patient wellbeing, treatment may be delayed resulting in development of complications as the first clinical manifestation of the disease. Antithrombotic prevention in AF combined with strict blood pressure control is of primary importance, since stroke risk and bleeding risk are both greater with underlying hypertension.

SAMe-TT2R2 Score in the Outpatient Anticoagulation Clinic to Predict Time in Therapeutic Range and Adverse Events

Background

The SAMe-TT₂R₂ score was developed to predict which patients on oral anticoagulation with vitamin K antagonists (VKAs) will reach an adequate time in therapeutic range (TTR) (> 65%-70%). Studies have reported a relationship between this score and the occurrence of adverse events.

Objective

To describe the TTR according to the score, in addition to relating the score obtained with the occurrence of adverse events in patients with nonvalvular atrial fibrillation (AF) on oral anticoagulation with VKAs.

Methods

Retrospective cohort study including patients with nonvalvular AF attending an outpatient anticoagulation clinic of a tertiary hospital. Visits to the outpatient clinic and emergency, as well as hospital admissions to the institution, during 2014 were evaluated. The TTR was calculated through the Rosendaal´s method.

Results

We analyzed 263 patients (median TTR, 62.5%). The low-risk group (score 0-1) had a better median TTR as compared with the high-risk group (score ≥ 2): 69.2% vs. 56.3%, p = 0.002. Similarly, the percentage of patients with TTR ≥ 60%, 65% or 70% was higher in the low-risk group (p < 0.001, p = 0.001 and p = 0.003, respectively). The high-risk group had a higher percentage of adverse events (11.2% vs. 7.2%), although not significant (p = 0.369).

Conclusions

The SAMe-TT₂R₂ score proved to be effective to predict patients with a better TTR, but was not associated with adverse events.

SAMe-TT2R2 predicts quality of anticoagulation in patients with acute venous thromboembolism: The MAQI2 experience

A high SAMe-TT₂R₂ score predicted poor warfarin control and adverse events among atrial fibrillation patients. However, the SAMe-TT₂R₂ score has not been well validated in venous thromboembolism (VTE) patients. A cohort of 1943 warfarin-treated patients with acute VTE was analyzed to correlate the SAMe-TT₂R₂ score with time in therapeutic range (TTR) and clinical adverse events. A TTR <60% was more frequent among patients with a high (>2) versus low (0-1) SAMe-TT₂R₂ score (63.4% vs 52.3%, p<0.0001). A high SAMe-TT₂R₂ score (>2) correlated with increased overall adverse events (7.9 vs 4.5 overall adverse events/100 patient years, p=0.002), driven primarily by increased recurrent VTE rates (4.2 vs 1.5 recurrent VTE/100 patient years, p=0.0003). The SAMe-TT₂R₂ score had a modest predictive ability for international normalized ratio (INR) quality and adverse clinical events among warfarin-treated VTE patients. The utility of the SAMe-TT₂R₂ score to guide clinical decision-making remains to be investigated.

Determinants of Time in Therapeutic Range in Patients Receiving Oral Anticoagulants (A Substudy of IMPACT)

Implanted cardiac arrhythmia devices can detect atrial tachyarrhythmias (atrial high-rate episodes [AHREs]) that are considered to correlate with atrial fibrillation and risk of stroke. In the IMPACT trial, oral anticoagulation was initiated when AHREs were detected by implanted cardioverter-defibrillators and withdrawn when they abated, according to a protocol accounting both for AHRE duration as detected by remote device monitoring and stroke risk assessment. In this analysis, we ascertained determinants of time in therapeutic range (TTR) among protocol-determined vitamin K antagonist-treated patients during the trial. We enrolled 2,718 patients with at least 1 additional stroke risk factor (CHADS₂ score ≥1) at 104 arrhythmia centers. The sex, age <60, medical history, treatments interacting with VKA, tobacco use (2 points) and race (2 points for non-Caucasian) (SAMe-TT₂R₂) score is a simple clinical-derived score designed to aid decision-making on whether a patient is likely to achieve good anticoagulation control on vitamin K antagonist (e.g., warfarin), which was calculated and related to TTR achieved using the Rosendaal method. We analyzed 229 patients (mean age 66.7 years; mean CHADS₂ score 2.85 [SD 1.1]) with mean TTR of 0.536 (SD 0.23) overall. Univariate analysis identified 5 variables associated with differences in mean TTR. Mean TTR was lower in those who were women (p = 0.031), of black race (p = 0.005) and in New York Heart Association class IV (p = 0.014), whereas hemoglobin >13.5 g/dl (p = 0.010) and New York Heart Association class I (p = 0.037) were associated with higher mean TTR. There was a significant difference in mean TTR value between US and non-US sites (Canada and Germany) (mean TTR for US: 0.513 vs non-US: 0.686; p <0.0001). Mean TTR was significantly lower (Δ = 0.1382, 95% CI 0.0382 to 0.2382) for patients with SAMe-TT₂R₂ scores of 4 (p = 0.007) and higher (Δ = 0.0612, 95% CI 0.0005 to 0.1219) for patients with SAMe-TT₂R₂ scores of 1 (p = 0.048). Linear regression confirmed a significant association between lower SAMe-TT₂R₂ score and improved anticoagulation control (p = 0.0021) with a 1-unit decrease in SAMe-TT₂R₂ score associated with an increase in TTR of 0.0404 (95% CI 0.0149 to 0.0659). In conclusion, clinical, geographical, and demographic factors were associated with the quality of anticoagulation control as reflected by TTR. Although overall TTR in this population was poor, lower SAMe-TT₂R₂ scores were associated with better TTR.

Stroke Prevention in Atrial Fibrillation: Focus on Latin America

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, with an estimated prevalence of 1-2% in North America and Europe. The increased prevalence of AF in Latin America is associated with an ageing general population, along with poor control of key risk factors, including hypertension. As a result, stroke prevalence and associated mortality have increased dramatically in the region. Therefore, the need for effective anticoagulation strategies in Latin America is clear. The aim of this review is to provide a contemporary overview of anticoagulants for stroke prevention. The use of vitamin K antagonists (VKAs, eg, warfarin) and aspirin in the prevention of stroke in patients with AF in Latin America remains common, although around one fifth of all AF patients receive no anticoagulation. Warfarin use is complicated by a lack of access to effective monitoring services coupled with an unpredictable pharmacokinetic profile. The overuse of aspirin is associated with significant bleeding risks and reduced efficacy for stroke prevention in this patient group. The non-VKA oral anticoagulants (NOACbs) represent a potential means of overcoming many limitations associated with VKA and aspirin use, including a reduction in the need for monitoring and a reduced risk of hemorrhagic events. The ultimate decision of which anticoagulant drug to utilize in AF patients depends on a multitude of factors. More research is needed to appreciate the impact of these factors in the Latin American population and thereby reduce the burden of AF-associated stroke in this region.

Antiplatelet and Antithrombotic Therapy in Patients with Atrial Fibrillation Undergoing Coronary Stenting

Stroke prevention is the main priority in the management cascade of atrial fibrillation. Most patients require long-term oral anticoagulation (OAC) and may require percutaneous coronary intervention. Prevention of recurrent cardiac ischemia and stent thrombosis necessitate dual antiplatelet therapy (DAPT) for up to 12 months. Triple antithrombotic therapy with OAC plus DAPT of shortest feasible duration is warranted, followed by dual antithrombotic therapy of OAC and antiplatelet agent, and OAC alone after 12 months. Because of elevated risk of hemorrhagic complications, new-generation drug-eluting stents, lower-intensity OAC, radial access, and routine use of gastric protection with proton pump inhibitors are recommended.

Factors Affecting the Quality of Anticoagulation With Vitamin K Antagonists in Venous Thromboembolism Patients

Introduction:

Treatment of venous thromboembolism (VTE) is classically based on oral vitamin K antagonists (VKAs). Due to the disadvantages and side effects of these drugs, monitoring the quality of anticoagulation by assessing time within therapeutic range (TTR) is recommended. Variables altering the TTR in patients with VTE are yet to be determined. The aim of this study was to analyze the quality of anticoagulation in patients with VTE treated with VKAs and to identify factors associated with poor-quality anticoagulation.

Methods:

A retrospective observational study was performed in a cohort of 94 patients diagnosed with VTE undergoing treatment with VKAs. The TTR at 6 months was analyzed by the Rosendaal method. Univariate and a multivariate logistic regression analyses were performed to unravel factors that increase risk of poor-quality anticoagulation.

Results:

The TTR at 6 months in this cohort was 60.5%; 54 patients had a TTR < 65%. In the univariate analysis, female sex, age ≥ 65 years, and renal impairment were significantly associated with poor-quality anticoagulation. However, in the multivariate logistic regression model, only renal impairment was independently associated with poor-quality anticoagulation (odds ratio = 3.31, 95% confidence interval [1.049, 10.486], p = .041).

Discussion:

The average quality of anticoagulation was 60.5%, and a high percentage of patients had a quality of anticoagulation below recommended levels. Study findings indicate that renal impairment is an independent risk factor for poor-quality anticoagulation in patients with VTE treated with VKAs.

Evaluation of SAMe-TT2R2 score and other clinical factors influencing the quality of anticoagulation therapy in non-valvular atrial fibrillation: a nationwide study in Spain

OBJECTIVE

To assess the major clinical factors affecting the quality of anticoagulation and evaluate the predictive value of the SAMe-TT2R2 score to identify patients who will achieve a high average time in therapeutic range (T.T.R.) with vitamin K antagonist (V.K.A.) treatment.

RESEARCH DESIGN AND METHODS

This observational, cross-sectional, retrospective and nationwide multicenter study included 1524 patients from the primary care setting with non-valvular atrial fibrillation receiving V.K.A. (≥12 months). We performed a bivariate analysis to identify factors individually associated with the T.T.R. and a multiple regression analysis to identify the independent predictive factors. For the validation of the SAMe-TT2R2 score, the receiver operating characteristic (R.O.C.) curve was calculated and the Hosmer-Lemeshow test was used to test calibration.

RESULTS

A total of 94.8% of patients received acenocumarol (4.8% warfarin). A progressive decrease in mean T.T.R. was found when the SAMe-TT2R2 score increased from 0 points (72.1 ± 17.1%) to 4 points (64.1 ± 23.2%), p < 0.001. Other risk scores (CHADS2 and CHA2DS2-VASc, HAS-BLED) were also associated with the mean T.T.R. We found a significant association between low T.T.R. and the following clinical factors: female sex, three or more comorbidities, amiodarone treatment, dietary habits, bleeding history and the intake of ≥7 tablets per day besides V.K.A. (p < 0.01). Regarding SAMe-TT2R2 score validation, the R.O.C. curve showed significant capability, although not high, of discriminating good anticoagulation control (T.T.R. ≥65%) with an area under the curve of 0.562 (95% C.I. 0.533-0.592, p < 0.001) which increased, remaining modest, to 0.594 (95% C.I. 0.564-0.624, p < 0.001) when the factors not included in SAMe-TT2R2 score were added.

CONCLUSION

In this cohort, the SAMe-TT2R2 score had a significant, although modest, ability to assess the likelihood of good international normalized ration (I.N.R.) control, and its predictive value might slightly improve by adding other simple clinical factors. Further research is needed to refine the predictive scales.

Edoxaban in venous thromboembolism and stroke prevention: an appraisal

Oral anticoagulation is the therapeutic cornerstone in preventing thromboembolic risk in both atrial fibrillation (AF) and venous thromboembolism (VTE). After decades of the sole therapeutic oral anticoagulation option being warfarin, the introduction of non-vitamin K antagonist oral anticoagulants has heralded a new era. Edoxaban is the latest addition to these available for clinical use. Edoxaban was as effective and safer than warfarin in preventing thromboembolic risk in AF patients. Similarly, edoxaban effectiveness and safety was evident when treating VTE patients to prevent recurrent VTE or VTE-related death. Therefore, edoxaban represents a valuable alternative in treating thromboembolic risk for AF and VTE patients.

Emerging Tools for Stroke Prevention in Atrial Fibrillation

Ischaemic strokes resulting from atrial fibrillation (AF) constitute a devastating condition for patients and their carers with huge burden on health care systems. Prophylactic treatment against systemic embolization and ischaemic strokes is the cornerstone for the management of AF. Effective stroke prevention requires the use of the vitamin K antagonists or non-vitamin K oral anticoagulants (NOACs). This article summarises the latest developments in the field of stroke prevention in AF and aims to assist physicians with the choice of oral anticoagulant for patients with non-valvular AF with different risk factor profile.

Updated European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist anticoagulants in patients with non-valvular atrial fibrillation

The current manuscript is an update of the original Practical Guide, published in June 2013[Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, et al. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace 2013;15:625-51; Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, et al. EHRA practical guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation: executive summary. Eur Heart J 2013;34:2094-106]. Non-vitamin K antagonist oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with non-valvular atrial fibrillation (AF). Both physicians and patients have to learn how to use these drugs effectively and safely in clinical practice. Many unresolved questions on how to optimally use these drugs in specific clinical situations remain. The European Heart Rhythm Association set out to coordinate a unified way of informing physicians on the use of the different NOACs. A writing group defined what needs to be considered as 'non-valvular AF' and listed 15 topics of concrete clinical scenarios for which practical answers were formulated, based on available evidence. The 15 topics are (i) practical start-up and follow-up scheme for patients on NOACs; (ii) how to measure the anticoagulant effect of NOACs; (iii) drug-drug interactions and pharmacokinetics of NOACs; (iv) switching between anticoagulant regimens; (v) ensuring adherence of NOAC intake; (vi) how to deal with dosing errors; (vii) patients with chronic kidney disease; (viii) what to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a risk of bleeding?; (xi) management of bleeding complications; (x) patients undergoing a planned surgical intervention or ablation; (xi) patients undergoing an urgent surgical intervention; (xii) patients with AF and coronary artery disease; (xiii) cardioversion in a NOAC-treated patient; (xiv) patients presenting with acute stroke while on NOACs; and (xv) NOACs vs. VKAs in AF patients with a malignancy. Additional information and downloads of the text and anticoagulation cards in >16 languages can be found on an European Heart Rhythm Association web site (www.NOACforAF.eu).