The SAMe-TT2R2 Score Predicts Poor Anticoagulation Control in AF Patients: A Prospective 'Real-world' Inception Cohort Study

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 ABC Bleeding Score and SAMe-TT2R2 Score on the Risk of Bleeding after Anticoagulation in Patients with Nonvalvular Atrial Fibrillation Complicated with Coronary Heart Disease

Objective

To explore the predictive value of ABC bleeding score and SAMe-TT2R2 score on the risk of bleeding in patients with nonvalvular atrial fibrillation (NVAF) complicated with coronary heart disease (CHD) after anticoagulation.

Methods

149 patients with NVAF complicated with CHD were followed up in our hospital for one year. The bleeding events during the follow-up period were observed, the ABC bleeding score and SAMe-TT2R2 score were calculated, the predictive value of the two scoring methods for the main bleeding risk was analyzed by the ROC curve, and the AUC area under the ROC curve of the two scoring methods was compared by the Delong test.

Results

There were 32 bleeding events during the follow-up period. The AUC of ABC bleeding score and SAMe-TT2R2 score were 0.775 (P < 0.01) and 0.624 (P < 0.05), respectively. The Delong test showed that the AUC of ABC bleeding score was significantly higher than that of SAMe-TT2R2 score (d = 2.177, P < 0.05).

Conclusion

Both the ABC bleeding score and SAMe-TT2R2 score can predict the risk of bleeding after anticoagulation in patients with NVAF and CHD. The critical value of the SAMe-TT2R2 score for predicting bleeding events in patients with NVAF and CHD may need to be increased to 4 or 5, and the prediction ability of ABC bleeding score is significantly better than that of the SAMe-TT2R2 score.

2021 Focused Update Consensus Guidelines of the Asia Pacific Heart Rhythm Society on Stroke Prevention in Atrial Fibrillation: Executive Summary

The consensus of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation (AF) has been published in 2017 which provided useful clinical guidance for cardiologists, neurologists, geriatricians, and general practitioners in the Asia-Pacific region. In these years, many important new data regarding stroke prevention in AF were reported. The practice guidelines subcommittee members comprehensively reviewed updated information on stroke prevention in AF, and summarized them in this 2021 focused update of the 2017 consensus guidelines of the APHRS on stroke prevention in AF. We highlighted and focused on several issues, including the importance of the AF Better Care pathway, the advantages of non-vitamin K antagonist oral anticoagulants (NOACs) for Asians, the considerations of use of NOACs for Asian AF patients with single one stroke risk factor beyond gender, the role of lifestyle factors on stroke risk, the use of oral anticoagulants during the "coronavirus disease 2019" pandemic, etc. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician's decision remains the most important factor in the management of AF.

2021 Focused update of the 2017 consensus guidelines of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation

The consensus of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation (AF) has been published in 2017 which provided useful clinical guidance for cardiologists, neurologists, geriatricians, and general practitioners in Asia-Pacific region. In these years, many important new data regarding stroke prevention in AF were reported. The Practice Guidelines subcommittee members comprehensively reviewed updated information on stroke prevention in AF, and summarized them in this 2021 focused update of the 2017 consensus guidelines of the APHRS on stroke prevention in AF. We highlighted and focused on several issues, including the importance of AF Better Care (ABC) pathway, the advantages of non-vitamin K antagonist oral anticoagulants (NOACs) for Asians, the considerations of use of NOACs for Asian patients with AF with single 1 stroke risk factor beyond gender, the role of lifestyle factors on stroke risk, the use of oral anticoagulants during the "coronavirus disease 2019" (COVID-19) pandemic, etc. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician's decision remains the most important factor in the management of AF.

Factors predicting poor anticoagulant control on warfarin in a Thai population with non-valvular atrial fibrillation (NVAF): the ACAChE score

Background

In many low- to middle-income countries in Asia, patients with NVAF usually received warfarin for thromboembolic prevention due to cost-effectiveness. The SAMe-TT2R2 score has been proposed to predict TTR in NVAF patients. However, the SAMe-TT2R2 score has not been much validated in Asian population. Interestingly, it may overestimate patients who had TTR < 65% due to regarding being Asians as a risk factor.

Objectives

To determine the factors predicting poor anticoagulant control on warfarin, create new scoring system, and compare with the SAMe-TT2R2 score in a Thai population with NVAF.

Methods

This is a retrospective study in a tertiary care hospital. We enrolled NVAF patients who received warfarin from January 2014 to December 2018. TTR was calculated based on Rosendaal method. Multiple logistic regression and AUC-ROC curve were used for analysis.

Results

A total of 864 patients were enrolled with mean age of 73.6 ± 11.58 years. The mean TTR was 48.1 ± 25.2%. Using multivariate regression analysis, the predictive factors for TTR < 65% were antiplatelet use (OR 4.49, p ≤ 0.001), LVEF < 40% (OR 1.92, p = 0.037), chronic kidney disease (GFR < 50 ml/min/1.73 m2) (OR 1.68, p = 0.013), history of CHF (OR 1.7, p = 0.047), and age ≥ 75 years (OR 1.4, p = 0.037). Based on the regression coefficients, we developed the new scoring system called ACAChE score [A, antiplatelet use (4 points); C, chronic kidney disease, GFR < 50 ml/min/1.73 m2 (2 points); A, age ≥ 75 years (1 point); Ch, history of CHF (2 points); E, LVEF < 40% (2 points)]. ROC curve showed discrimination performance of the ACAChE score and SAMe-TT2R2 score for prediction of TTR < 65% with the C-statistic of 0.62 (95%CI 0.57–0.65) and 0.54 (95%CI 0.50–0.58), respectively.

Conclusion

In Thai NVAF patients, the ACAChE score (antiplatelet use, chronic kidney disease (GFR < 50 ml/min/1.73 m2), age ≥ 75 years, history of congestive heart failure, and LVEF < 40%) has better prediction for TTR < 65% than SAMe-TT2R2 score. Thus, it expected to guide the selection of oral anticoagulation in Asian patients with NVAF.

Effect of SAMe-TT2R2 score and genetic polymorphism on the quality of anticoagulation control in Qatari patients treated with warfarin

There is no strong evidence on pharmacogenetics role on the quality of INR control after the initiation phase and on the maintenance of stable INR on the long term as measured by the time in therapeutic range (TTR). The benefit of a score such as SAMe-TT₂R₂ is that it can preemptively guide clinicians on whether to start the patient on warfarin or direct oral anticoagulant. To determine the association between genetic variants in CYP2C9, VKORC1, and CYP4F2 and TTR. To validate SAMe-TT₂R₂ score predictive ability on the quality of anticoagulation in Qatari patients. This is an observational nested case–control study that was conducted on a cohort of Qatari patients treated with warfarin with previously identified genotype for the CYP2C9, VKORC1, and CYP2F4. The sample size of this cohort was 148 patients. Mean TTR was 62.7 ± 21%. TTR was not significantly different among carriers of the CYP2C9*2 &*3, VKORC1(–1639G>A) or CYP4F2*3 compared to their non-carriers alleles. None of the factors in the SAMe-TT₂R₂ score had a significant effect on the TTR except for the female gender where TTR was significantly lower in females (n = 89) compared to males (n = 59) (59.6 ± 21% vs. 67.2 ± 20%, p = 0.03). Furthermore, patients with SAMe-TT₂R₂ score of zero had significantly better TTR compared to those with higher scores (76.5 ± 17% vs. 61.8 ± 21%, p = 0.04). Logistic regression analysis showed that high SAMe-TT₂R₂ score was the only statistically significant predicting factor of poor INR control (odds ratio (OR) 5.7, 95% confidence interval (CI) 1.1–28.3, p = 0.034). Genetic variants have no contribution to the quality of INR control. SAMe-TT₂R₂ score was predictive for the poor quality of anticoagulation in a cohort of Qatari patients.

A new index to predict quality of anticoagulation control in patients on vitamin K antagonists: the DAFNE score

Aim: To derive a new clinical score to improve the prediction of those at risk of poor International Normalized Ratio control among patients with atrial fibrillation taking vitamin K antagonists. Materials & methods: The score was calculated using PAULA database and validated in the FANTASIIA population. Results: The DAFNE score (cardiovascular Disease, concomitant treatment with Amiodarone, Food/dietary transgression and taking ≥7 pills daily, fEemale sex) score was related to a higher probability of poor International Normalized Ratio control. C-indexes were 0.611 and 0.576 (De Long test, p = 0.007) for the DAFNE and SAMe-TT₂R₂ scores, respectively. Conclusion: The DAFNE score is a new clinical score which may potentially help determine those patients with atrial fibrillation who are at high risk of poor anticoagulation control with vitamin K antagonists.

A nurse-led atrial fibrillation clinic: Impact on anticoagulation therapy and clinical outcomes

BACKGROUND

Nurses play a central role in the management of atrial fibrillation (AF) patients. An unresolved question is whether a nurse-led clinic would improve clinical outcomes. Herein, we investigated the impact of a nurse-led clinic on anticoagulation therapy and clinical outcomes in a cohort of naïve AF patients.

METHODS

Prospective study including AF patients starting vitamin K antagonists (VKAs) into a nurse-led AF clinic. These patients were followed in this specific AF clinic. Additionally, AF patients already taking VKAs for 6 months followed according to the routine clinical practice were included as comparison group. The quality of anticoagulation was assessed at 6 months. Efficacy and safety endpoints were recorded during follow-up.

RESULTS

We included 223 patients (Nurse-led clinic: 107; Usual care: 116). The mean time in therapeutic range and the proportion of INRs within the therapeutic range were similar in both groups. During 2.06 (IQR 1.01-2.94) years of follow-up, 64 (28.7%) patients changed to direct-acting oral anticoagulants. The proportion of switchers was higher in the nurse-led clinic (37.4%) than in the usual care group (20.7%) (P = .006) and these patients spent less time to switch (2.0 [IQR 0.7-2.9] vs 6.0 [IQR 3.7-11.2] years; P < .001). Importantly, the annual rate of ischaemic stroke/TIA was significantly lower in the nurse-led clinic (0.47%/year vs 3.88%/year, P = .016), without differences in safety endpoints.

CONCLUSION

A nurse-led AF clinic may offer a "patient-centered" review and holistic follow-up, and it would be associated with a reduction of ischaemic stroke/TIA, without increasing bleeding complications. Further studies should confirm these results.

A Delphi consensus on the management of oral anticoagulation in patients with non-valvular atrial fibrillation in Spain: ACOPREFERENCE study

OBJECTIVE

To evaluate the level of agreement between cardiologists regarding the management of oral anticoagulation (OAC) in patients with non-valvular atrial fibrillation (NVAF) in Spain.

MATERIALS AND METHODS

A two-round Delphi study was performed using an online survey. In round 1, panel members rated their level of agreement with the questionnaire items on a 9-point Likert scale. Item selection was based on acceptance by ≥66.6% of panellists and the agreement of the scientific committee. In round 2, the same panellists evaluated those items that did not meet consensus in round 1.

RESULTS

A total of 238 experts participated in round 1; of these, 217 completed the round 2 survey. In round 1, 111 items from 4 dimensions (Thromboembolic and bleeding risk evaluation for treatment decision-making: 18 items; Choice of OAC: 39 items; OAC in specific cardiology situations: 12 items; Patient participation and education: 42 items) were evaluated. Consensus was reached for 92 items (83%). Over 80% of the experts agreed with the use of DOACs as the initial anticoagulant treatment when OAC is indicated. Panellists recommended the use of DOACs in patients at high risk of thromboembolic complications (CHA2DS2-VASc ≥3) (83%), haemorrhages (HAS-BLED ≥3) (89%) and poor quality of anticoagulation control (SAMe-TT2R2 >2) (76%), patients who fail to achieve an optimal therapeutic range after 3 months on VKA treatment (93%), and those who are to undergo cardioversion (80%). Panellists agreed that the efficacy and safety profile of each DOAC (98%), the availability of a specific reversal agent (72%) and patient's preference (85%) should be considered when prescribing a DOAC. A total of 97 items were ultimately accepted after round 2.

CONCLUSIONS

This Delphi panel study provides expert-based recommendations that may offer guidance on clinical decision-making for the management of OAC in NVAF. The importance of patient education and involvement has been highlighted.

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).

Evaluation of SAMe-TT2R2 Score on Predicting Success With Extended-Interval Warfarin Monitoring

BACKGROUND

In patients with stable international normalized ratios, 12-week extended-interval warfarin monitoring can be considered; however, predictors of success with this strategy are unknown. The previously validated SAMe-TT₂R₂ score (considering sex, age, medical history, treatment, tobacco, and race) predicts anticoagulation control during standard follow-up (every 4 weeks), with lower scores associated with greater time in therapeutic range.

OBJECTIVE

To evaluate the ability of the SAMe-TT₂R₂ score in predicting success with extended-interval warfarin follow-up in patients with previously stable warfarin doses.

METHODS

In this post hoc analysis of a single-arm feasibility study, baseline SAMe-TT₂R₂ scores were calculated for patients with ≥1 extended-interval follow-up visit. The primary analysis assessed achieved weeks of extended-interval follow-up according to baseline SAMe-TT₂R₂ scores.

RESULTS

A total of 47 patients receiving chronic anticoagulation completed a median of 36 weeks of extended-interval follow-up. The median baseline SAMe-TT₂R₂ score was 1 (range 0-5). Lower SAMe-TT₂R₂ scores appeared to be associated with greater duration of extended-interval follow-up achieved, though the differences between scores were not statistically significant. No individual variable of the SAMe-TT₂R₂ score was associated with achieved weeks of extended-interval follow-up. Analysis of additional patient factors found that longer duration (≥24 weeks) of prior stable treatment was significantly associated with greater weeks of extended-interval follow-up completed ( P = 0.04). Conclusion and Relevance: This pilot study provides limited evidence that the SAMe-TT₂R₂ score predicts success with extended-interval warfarin follow-up but requires confirmation in a larger study. Further research is also necessary to establish additional predictors of successful extended-interval warfarin follow-up.

Time to therapeutic range (TtTR), anticoagulation control, and cardiovascular events in vitamin K antagonists-naive patients with atrial fibrillation

BACKGROUND

Vitamin K antagonists (VKAs) reduce cardiovascular events (CVEs) in atrial fibrillation (AF) when a time in therapeutic range (TiTR) >70% is achieved. Factors affecting the time to achieve the TR (TtTR) are unknown.

METHODS

Prospective observational study including 1,406 nonvalvular AF patients starting VKAs followed for a mean of 31.3months (3,690 patient/year); TiTR, TtTR, and SAMe-TT₂R₂ score were calculated, and CVEs were recorded.

RESULTS

Median TtTR was 8.0days (interquartile range 5.0-18.0). Patients with high TtTR (ie, >75th percentile) were more likely to be in AF than in sinus rhythm at entry (odds ratio [OR]: 1.423, P=.011). Median TiTR was 60.0%; low TiTR (below median) was associated with SAMe-TT₂R₂ score (OR: 1.175, P=.001), high TtTR (>75th percentile, OR: 1.357, P=.017), and number of international normalized ratio checks (OR: 0.998, P=.049). We recorded 113 CVEs (3.1%/y), with a higher rate seen in patients with TtTR >75th percentile compared to those below (log-rank test, P=.006). A multivariable Cox regression analysis showed that SAMe-TT₂R₂ score (hazard ratio [HR]: 1.331, P<.001), TtTR >75th percentile (HR: 1.505, P=.047), TiTR <70% (HR: 1.931, P=.004), number of international normalized ratio checks (HR: 0.988, P<.001), digoxin (HR: 1.855, P=.008), and proton-pump inhibitors (HR: 0.452, P<.001) were independently associated with CVEs.

CONCLUSIONS

High TtTR is associated with poorer long-term quality of VKAs therapy. Patients with TtTR >18days or with high SAMe-TT₂R₂ score should be considered for treatment with non-vitamin K oral anticoagulants.

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.

Reduced Time in Therapeutic Range and Higher Mortality in Atrial Fibrillation Patients Taking Acenocoumarol

PURPOSE

The efficacy and tolerability of vitamin K antagonists (VKAs) depends on the quality of anticoagulant control, reflected by the mean time in therapeutic range (TTR) of international normalized ratio 2.0 to 3.0. In the present study, we aimed to investigate the association between TTR and change in TTR (ΔTTR) with the risk of mortality and clinically significant events in a consecutive cohort of atrial fibrillation (AF) patients.

METHODS

We included 1361 AF patients stable on VKAs (international normalized ratio 2.0-3.0) during at least the previous 6 months. After 6 months of follow-up we recalculated TTR, calculated ΔTTR (ie, the difference between baseline and 6-month TTRs) and investigated the association of both with the risk of mortality and "clinically significant events" (defined as the composite of stroke or systemic embolism, major bleeding, acute coronary syndrome, acute heart failure, and all-cause deaths).

FINDINGS

The median ΔTTR at 6 months of entry was 20% (interquartile range 0-34%), 796 (58.5%) patients had a TTR reduction of at least 20%, while 330 (24.2%) had a TTR <65%. During follow-up, 34 (2.5% [4.16% per year]) patients died and 61 (4.5% [7.47% per year]) had a clinically significant event. Median ΔTTR was significantly higher in patients who died (35.5% vs 20%; P = 0.002) or sustained clinically significant events (28% vs 20%; P = 0.022). Based on Cox regression analyses, the overall risk of mortality at 6 months for each decrease point in TTR was 1.02 (95% CI, 1.01-1.04; P = 0.003), and the risk of clinically significant events was 1.01 (95% CI, 1.00-1.03; P = 0.028). Patients with TTR <65% at 6 months had higher risk of mortality (hazard ratio = 2.96; 95% CI, 1.51-5.81; P = 0.002) and clinically significant events (hazard ratio = 1.71; 95% CI, 1.01-2.88; P = 0.046).

IMPLICATIONS

Our findings suggest that in AF patients anticoagulated with VKAs, a change in TTR over 6 months (ie, ΔTTR) is an independent risk factor for mortality and clinically significant events. Even in a cohort with good anticoagulation control, the risk for mortality and clinically significant events increases with every point deterioration of TTR.

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.

Clinical Prediction Model for Time in Therapeutic Range While on Warfarin in Newly Diagnosed Atrial Fibrillation

BACKGROUND

Though warfarin has historically been the primary oral anticoagulant for stroke prevention in newly diagnosed atrial fibrillation (AF), several new direct oral anticoagulants may be preferred when anticoagulation control with warfarin is expected to be poor. This study developed a prediction model for time in therapeutic range (TTR) among newly diagnosed AF patients on newly initiated warfarin as a tool to assist decision making between warfarin and direct oral anticoagulants.

METHODS AND RESULTS

This electronic medical record-based, retrospective study included newly diagnosed, nonvalvular AF patients with no recent warfarin exposure receiving primary care services through a large healthcare system in rural Pennsylvania. TTR was estimated as the percentage of time international normalized ratio measurements were between 2.0 and 3.0 during the first year following warfarin initiation. Candidate predictors of TTR were chosen from data elements collected during usual clinical care. A TTR prediction model was developed and temporally validated and its predictive performance was compared with the SAMe-TT2R2 score (sex, age, medical history, treatment, tobacco, race) using R2 and c-statistics. A total of 7877 newly diagnosed AF patients met study inclusion criteria. Median (interquartile range) TTR within the first year of starting warfarin was 51% (32, 67). Of 85 candidate predictors evaluated, 15 were included in the final validated model with an R2 of 15.4%. The proposed model showed better predictive performance than the SAMe-TT2R2 score (R2=3.0%).

CONCLUSIONS

The proposed prediction model may assist decision making on the proper mode of oral anticoagulant among newly diagnosed AF patients. However, predicting TTR on warfarin remains challenging.

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.

Clinical Stroke prevention in atrial fibrillation

Oral anticoagulation therapy has reduced the risk of ischaemic stroke and improved the outcomes for patients with atrial fibrillation considerably. The emergence of the non-vitamin K oral anticoagulants as alternatives to vitamin K antagonists has significantly changed the practice of stroke prevention in atrial fibrillation. As the main complication with antithrombotic therapy is bleeding, physicians should always balance the risk of ischaemic stroke against intracranial haemorrhage and intervene where appropriate to reduce both risks. Individual approach is often mandatory due to heterogeneity of the risks and patient preferences. The purpose of this review is to summarise the current knowledge of the oral anticoagulation therapy in atrial fibrillation patients and guide physicians with the management of anticoagulants based on data from clinical trials and systematic reviews.

Decision-Making in Clinical Practice: Oral Anticoagulant Therapy in Patients with Non-valvular Atrial Fibrillation and a Single Additional Stroke Risk Factor

Approximately 1 in 3-4 patients presenting with an ischemic stroke will also have atrial fibrillation (AF), and AF-related strokes can be effectively prevented using oral anticoagulant therapy (OAC), either with well-controlled vitamin K antagonists (VKAs) or non-vitamin K antagonist oral anticoagulants (NOACs). In addition, OAC use (both VKAs and NOACs) is associated with a 26% reduction in all-cause mortality (VKAs) or an additional 10% mortality reduction with NOACs relative to VKAs. The decision to use OAC in individual AF patient is based on the estimated balance of the benefit from ischemic stroke reduction against the risk of major OAC-related bleeding [essentially intracranial hemorrhage (ICH)]. Better appreciation of the importance of VKAs' anticoagulation quality [a target time in therapeutic range (TTR) of ≥70%] and the availability of NOACs (which offer better safety compared to VKAs) have decreased the estimated threshold for OAC treatment in AF patients towards lower stroke risk levels. Still, contemporary registry-based data show that OAC is often underused in AF patients at increased risk of stroke. The uncertainty whether to use OAC may be particularly pronounced in AF patients with a single additional stroke risk factor, who are often (mis)perceived as having a "borderline" or insufficient stroke risk to trigger the use of OAC. However, observational data from real-world AF cohorts show that the annual stroke rates in such patients are higher than in patients with no additional stroke risk factors, and OAC use has been associated with reduction in stroke, systemic embolism, or death in comparison to no therapy or aspirin, with no increase in the risk of bleeding relative to aspirin. In this review article, we summarize the basic principles of stroke risk stratification in AF patients and discuss contemporary real-world evidence on OAC use and outcomes of OAC treatment in AF patients with a single additional stroke risk factor in various real-world AF cohorts.

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.

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.

The Sex, Age, Medical History, Treatment, Tobacco Use, Race Risk (SAMe TT2R2) Score Predicts Warfarin Control in a Singaporean Population

BACKGROUND

Warfarin reduces stroke risk in atrial fibrillation (AF) patients but requires ongoing monitoring. Time in therapeutic range (TTR) is used as a measure of warfarin control, with a TTR less than 60% associated with adverse patient outcomes. The Sex, Age, Medical history, Treatment, Tobacco use, Race (SAMe-TT₂R₂) score has been identified as a model able to predict warfarin control, but this has been tested in mainly Caucasian populations. Therefore, the aim of this study was to determine the ability of the SAMe-TT₂R₂ score to predict warfarin control in a Singaporean population consisting of Chinese, Malay, and Indian race.

METHODS

Retrospective data were collected from the National Heart Centre Singapore for AF patients receiving warfarin between January and June 2014. The TTR and the SAMe-TT₂R₂ score were calculated for each patient.

RESULTS

The 1137 non-valvular AF patients had a mean TTR of 58.0 ± 34.3% and a median SAMe-TT₂R₂ score of 3. The categorized SAMe-TT₂R₂ scores (2 versus >2) showed a significant reduction in mean TTR for the entire population (63.2% versus 55.8%, P = .0004) and also when categorized according to race for Chinese (62.7% versus 56.9%, P = .0075) and Malay (68.4% versus 50.6%, P = .0131) populations.

CONCLUSION

The SAMe-TT₂R₂ tool is effective in predicting warfarin control in a Singaporean population as patients with a score greater than 2 had poor control. The minimum score for non-Caucasian patients is 2; thus, in these patients, the presence of any additional risk factors identified in the SAMe-TT₂R₂ tool categorizes them as unlikely to achieve adequate warfarin control and possible candidates for alternative anticoagulants.

A tailored treatment strategy: a modern approach for stroke prevention in patients with atrial fibrillation

The main priority in atrial fibrillation (AF) management is stroke prevention, following which decisions about rate or rhythm control are focused on the patient, being primarily for management of symptoms. Given that AF is commonly associated with various comorbidities, risk factors such as hypertension, heart failure, diabetes mellitus and sleep apnoea should be actively looked for and managed in a holistic approach to AF management. The objective of this review is to provide an overview of modern AF stroke prevention with a focus on tailored treatment strategies. Biomarkers and genetic factors have been proposed to help identify 'high-risk' patients to be targeted for oral anticoagulation, but ultimately their use must be balanced against that of more simple and practical considerations for everyday use. Current guidelines have directed focus on initial identification of 'truly low-risk' patients with AF, that is those patients with a CHA2 DS2 -VASc [congestive heart failure, hypertension, age ≥75 years (two points), diabetes mellitus, stroke (two points), vascular disease, age 65-74 years, sex category] score of 0 (male) or 1 (female), who do not need any antithrombotic therapy. Subsequently, patients with ≥1 stroke risk factors can be offered effective stroke prevention, that is oral anticoagulation. The SAMe-TT2 R2 [sex female, age <60 years, medical history (>2 comorbidities), treatment (interacting drugs), tobacco use (two points), race non-Caucasian (two points)] score can help physicians make informed decisions on those patients likely to do well on warfarin (SAMe-TT2 R2 score 0-2) or those who are likely to have a poor time in therapeutic range (SAMe-TT2 R2 score >2). A clinically focused tailored approach to assessment and stroke prevention in AF with the use of the CHA2 DS2 VASc, HAS-BLED [hypertension, abnormal renal/liver function (one or two points), stroke, bleeding history or predisposition, labile international normalized ratio, elderly (>65 years) drugs/alcohol concomitantly (one or two points)] and SAMeTT2 R2 scores to evaluate stroke risk, bleeding risk and likelihood of successful warfarin therapy, respectively, is discussed.

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).