Time In Therapeutic Range Values Research Articles

Association between gene polymorphisms and initial warfarin therapy in patients after heart valve surgery.

Warfarin is widely used for the prevention and treatment of thrombotic events. This study aimed to examine the influence of gene polymorphisms on the early stage of warfarin therapy in patients following heart valve surgery. Nine single nucleotide polymorphisms were genotyped using microarray chips, categorizing patients into three groups: normal responders (Group I), sensitive responders (Group II), and highly sensitive responders (Group III). The primary clinical outcomes examined were time in therapeutic range (TTR) and international normalized ratio (INR) variability. To investigate potential influencing factors, a generalized linear regression model was employed. Among 734 patients, the prevalence of CYP2C9*3-1075A > C, CYP2C19*3-636G > A, and CYP2C19*17-806C > T variants were 11.2%, 9.9%, and 1.9% of patients, respectively. VKORC1-1639G > A or the linked -1173C > T variant was observed in 99.0% of the patients. Generalized linear model analysis revealed an impact of sensitivity grouping on INR variability. Compared to Group I, Group II showed higher TTR values (p = 0.023), while INR variability was poorer in Group II (p < 0.001) and Group III (p < 0.001). Individual gene analysis identified significant associations between CYP2C9*3-1075A > C (p < 0.001), VKORC1-1639G > A or the linked -1173 C > T (p = 0.009) and GGCX-3261G > A (p = 0.019) with INR variability. The genotypes of CYP2C9, VKORC1, and GGCX were found to have a significant impact on INR variability during the initial phase of warfarin therapy. However, no significant association was observed between TTR and gene polymorphisms. These findings suggest that focusing on INR variability is crucial in clinical practice, and preoperative detection of gene polymorphisms should be considered to assist in the initiation of warfarin therapy.

The quality of pharmacist-led community warfarin management across 2 provinces in Canada: A cross-sectional observational study.

Guidelines for anticoagulation management services recommend personnel be specially trained in warfarin management and suggest using tools such as decision-support software. To date, there have been no Canadian studies documenting the quality of warfarin management using a similar guideline recommended approach. A cross-sectional, retrospective observational study was conducted to measure the quality of pharmacist-led warfarin management using point-of-care international normalized ratio (INR) testing and decision-support software in various ambulatory settings in Canada. Settings included 4 family health teams in Ontario and 40 community pharmacies across Nova Scotia. Quality was measured using time in therapeutic range (TTR) and was reported in 3 manners: mean TTR, median TTR and time-weighted mean TTR. The primary outcome included 963 patients. The combined mean and median TTR for the 2019 Ontario family health teams and Nova Scotia pharmacies was 74.2% and 77.3% (interquartile range 64%-87.9%), respectively. The time-weighted mean TTR was 76.3%. To the best of our knowledge, the TTR achieved by this model of care is the highest reported in Canadian general practice. Since Thrombosis Canada defines good-quality warfarin management as a TTR of 60% or greater, and many studies have reported an association between higher TTR values and lower rates of thrombosis and hemorrhage, this model of care may have significant benefits for patients. This study demonstrates the high quality of anticoagulation management provided by specially trained pharmacists using point-of-care INR testing and decision-support software. These results support expanded access to this service for all Canadians. Can Pharm J (Ott) 2024;157:xx-xx.

Comparing follow-up of patients with vitamin K antagonists in a health center: pre- and post- COVID-19 pandemic

Introduction and objectives: During the COVID-19 pandemic, the follow-up of patients treated with vitamin K antagonists (VKAs) may have been affected. This study aims to compare how these patients were monitored preand post-COVID-19 pandemic and understand the impact of non-face-to-face appointments on their follow-up. Methods: We conducted a retrospective cohort study in a Portuguese Health Center. The study included patients treated with VKAs and followed at the Health Center for international normalized ratio (INR) monitoring between March 2019 and March 2021. Data collected: sex, age, type of VKA; INR; date of INR assessment, type of appointment (face-to-face or phone/e-mail). Rosendaal’s method was used to calculate pre-COVID-19 and post-COVID-19 time in therapeutic range (TTR). Good TTR control was defined if values ≥ 70%. Results: 44 patients were included. The mean TTR in the pre-COVID-19 period was 64.55% (95% CI: 58.10 - 71.00%). The post-COVID-19 mean was slightly higher (+ 2.26%), 66.81% (95% CI: 59.66 - 73.97%), but the difference was not statistically significant (p = 0.576). The use of non-face-to-face appointments did not contribute to worsening post-pandemic TTR, showing no lower follow-up than during pre-pandemic period in which all contacts were face-to-face [CI (95%) -0.397 - 0.196 for a reference range -0.489 - 0.693]. Conclusions: The TTR value in both periods was similar and lower than the value defined for effective hypocoagulation. The use of non-face-to-face consultation in the post-COVID-19 period does not seem to have influenced the quality of hypocoagulation.

DOES THE TIMING OF WARFARIN INGESTION AFFECT THE TIME IN THERAPEUTIC RANGE IN PATIENTS WITH METALLIC PROSTHETIC VALVE?

Aim: Warfarin , a vitamin K antagonist, is the only approved oral agent to provide anticoagulation in patients with metallic prosthetic valves. Since effectively initiating and maintaining anticoagulation is challenging due to various factors , those patients undergo frequent periodic INR testing. The aim of this study was to investigate the effect of the timing of warfarin ingestion on the stability of anticoagulation.&#x0D; Materials and Methods: A total of 60 patients with metallic prosthetic valves were included in the study. First, all the patients were informed to take warfarin between 19:30 and 20:00 during the first month, then to take warfarin between 09:30 and 10:00 during the second month. All the patients underwent INR monitoring once every 15 days during the follow-up period. The time in therapeutic range (TTR) values for the first month and second month ( referred to as ‘first TTR’ and ‘second TTR’, respectively) were calculated separately using the Rosendaal method. &#x0D; Results: The mean age ( ± SD) of the patients was 59.6 ± 9.6 years and 36.7% (n=22) were male. There was no significant difference between the first TTR and second TTR values of the patients (66.23 ± 40.7% vs 64.12 ± 41.13%, p=0.783). The mean INR value in the first month was found to be significantly lower than in the second month (2.73 ± 0.53 vs 3.06 ± 0.47, p=0.001). &#x0D; Conclusion:.The study results showed that the timing of warfarin ingestion did not affect the stability of anticoagulation although taking the warfarin in the morning provided higher INR values.

Comparison of the real-life clinical outcomes of warfarin with effective time in therapeutic range and non-vitamin K antagonist oral anticoagulants: Insight from the AFTER-2 trial.

It is unclear whether warfarin treatment with high time in therapeutic range (TTR) is as effective and safe as non-vitamin K antagonist oral anticoagulants (NOACs). It is crucial to compare warfarin with effective TTR and NOACs to predict long-term adverse events in patients with atrial fibrillation. We aimed to compare the long-term follow-up results of patients with atrial fibrillation (AF) who use vitamin K antagonists (VKAs) with effective TTR and NOACs. A total of 1140 patients were followed at 35 different centers for five years. During the follow-up period, the international normalized ratio (INR) values were studied at least 4 times a year, and the TTR values were calculated according to the Roosendaal method. The effective TTR level was accepted as >60% as recommended by the guidelines. There were 254 patients in the effective TTR group and 886 patients in the NOAC group. Ischemic cerebrovascular disease/transient ischemic attack (CVD/TIA), intracranial bleeding, and mortality were considered primary endpoints based on one-year and five-year follow-ups. Ischemic CVD/TIA (3.9% vs. 6.2%; P = 0.17) and intracranial bleeding (0.4% vs. 0.5%; P = 0.69), the one-year mortality rate (7.1% vs. 8.1%; P = 0.59), the five-year mortality rate (24% vs. 26.3%; P = 0.46) were not different between the effective TTR and NOACs groups during the follow-up, respectively. The CHA2DS2-VASC score was similar between the warfarin with effective TTR group and the NOAC group (3 [2-4] vs. 3 [2-4]; P = 0.17, respectively). Additionally, survival free-time did not differ between the warfarin with effective TTR group and each NOAC in the Kaplan-Meier analysis (dabigatran; P = 0.59, rivaroxaban; P = 0.34, apixaban; P = 0.26, and edoxaban; P = 0.14). There was no significant difference in primary outcomes between the effective TTR and NOAC groups in AF patients.

Abstract 12046: Patient Characteristics and Use of Oral Anticoagulation Therapy in New-Onset Atrial Fibrillation: Results From a Nationwide Registry Study in Finland

Background and Aims: The risk of ischemic stroke associated with atrial fibrillation (AF) can be reduced with oral anticoagulation therapy (OAC). We examined the patient characteristics and nationwide use of OACs in primary and secondary care AF patients. Methods: The Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) -study is a nationwide study of AF patients that combines data from several Finnish health care registers. In this study all new-onset AF patients in Finland from January 2011 to December 2018 with laboratory data were analyzed. Comorbidities and CHA 2 DS 2 -VASc -score were recorded until date of AF diagnosis. First OAC therapies from diagnosis of AF to the end of study were analyzed. For warfarin users with sufficient laboratory data, time in therapeutic range (TTR) was calculated and patient quartiles by TTR were assigned. Results: Of the 130 533 (50.7 % male) new-onset AF patients studied, 96 051 (73.6%) used any OAC medication after AF diagnosis. The used OACs were warfarin (n= 56 857; 43.6%), apixaban (n=16 377; 12.5%) rivaroxaban (n=14 821; 11.4%), dabigatran (n=7 224; 5.5%), and edoxaban (n=723; 0.6%). The mean TTR values in warfarin TTR-quartiles were 32% (0-52%) in the 1 st quartile, 65% (56-72%) in the 2 nd quartile, 77% (72-83%) in the 3 rd quartile and 90% (83-100%) in the highest quartile. Among patients with standard dose of direct oral anticoagulants, the mean CHA 2 DS 2 VASc -score was 2.78 for dabigatran and 3.47 for apixaban. For patients with warfarin the mean CHA 2 DS 2- VASc -score was 3.50 in the highest quartile. The mean CHA 2 DS 2- VASc for patients without any OAC was 3.19. Conclusion: In unadjusted analyses patients with dabigatran had the lowest and patients with apixaban the highest mean CHA 2 DS 2- VASc score. In patients with warfarin, the highest TTR quartile had the lowest mean CHA 2 DS 2- VASc -score and mean TTR of 77%. Contrary to the guidelines, a remarkable number of patients with high CHA 2 DS 2- VASc score remained without any OAC treatment.

Blood pressure control measures and cardiovascular outcomes: a prospective hypertensive cohort

Purpose We investigated whether blood pressure (BP) control measures, visit-to-visit BP variability, and time in therapeutic range (TTR) are associated with future cardiovascular outcomes in hypertensive patients. Materials and Methods Among 1,408 hypertensive patients without cardiovascular disease, we prospectively evaluated the incident major cardiovascular events over 6 years. In newly diagnosed patients, antihypertensive drug treatment was initiated. We estimated two markers of on-treatment BP control, (1) visit-to-visit BPV as the coefficient of variation of office systolic BP (BP-CV), and (2) TTR calculated as the percentage of office systolic BP measurements within 120–140mmHg across visits. Results The hypertensive cohort (672 males, mean age 60 years, 31% newly diagnosed) had a mean systolic/diastolic BP of 142/87 mmHg. The mean number of visits was 4.9 ± 2.6, while the mean attained systolic/diastolic BP during follow-up was 137/79 mmHg using 2.7 ± 1.1 antihypertensive drugs. The BP-CV and TTR were 9.1 ± 4.1% and 45 ± 29%, respectively, and the incidence of the composite outcome was 8.3% (n = 117). After adjustment for relevant confounders and standardization to z-scores, BP-CV and TTR were associated with a 43% (95% CI, 27–62%) increase and a 33% (95% CI, 15–47%) reduction in the outcome. However, the joint evaluation of TTR and BP-CV in a common multivariable model indicated that a standardized change of TTR was associated with the outcome to a greater extent than BP-CV (mean hazard ratios of 30% vs. 24%, respectively). When combined with the higher BP standardized-CV quartile, the lower TTR quartile predicted the outcome by 2.3 times (95% CI, 1.1–5.4) compared to the inverse TTR and BP-CV quartile pattern. Conclusion High BP-CV or low TTR was associated with future cardiovascular events in a cohort of treated hypertensive patients. As a determinant, the extent of TTR value appears greater than BP-CV when these measures are considered in the same multivariable model.

Surrogates of the Left Ventricular Thrombus Resolution: A Retrospective Data Review.

The left ventricular thrombus is one of the serious complications of ischemic cardiomyopathy. In this study, we aimed to search for the independent factors to predict the resolution of left ventricular thrombus. This retrospective study included all patients with coronary artery disease, aged above 18 years old, and with the thrombus at the apical location of the left ventricle. Demographic, clinical, and echocardiographic characteristics of the patients were recorded. Major adverse cardiovascular events developed within the follow-up period were recorded. The time in the therapeutic range of each patient was calculated. The presence of left ventricular thrombus beyond 180 days despite warfarin usage was classified as persistent left ventricular thrombus. The study included 174 subjects (169 males and 5 females). The mean age of the study population was 54.5 ± 11.0 years. The number of patients in whom the left ventricular thrombus resolved with treatment in less than 180 days was 56 (32.2%). Median anticoagulation time in the study population was 252 [150-480] days and the meantime in the therapeutic range of the patients was 54 ± 19%. The time in therapeutic range value of the groups was similar (P=.593). It was found that concomitant clopidogrel use (P=.003) and left ventricular thrombus area (P < .001) were the independent predictors of left ventricular thrombus resolution within less than 180 days in the logistic regression analysis. Concomitant use of clopidogrel was found to be associated with left ventricular thrombus resolution but left ventricular thrombus size was related to left ventricular thrombus persistency. Although standard 3-6 months of anticoagulation is advised for left ventricular thrombus, considering the presence of these predictors in such patients may guide the physicians to individualize the treatment.

Surrogates of the Left Ventricular Thrombus Resolution: A Retrospective Data Review.

The left ventricular thrombus is one of the serious complications of ischemic cardiomyopathy. In this study, we aimed to search for the independent factors to predict the resolution of left ventricular thrombus.This retrospective study included all patients with coronary artery disease, aged above 18 years old, and with the thrombus at the apical location of the left ventricle. Demographic, clinical, and echocardiographic characteristics of the patients were recorded. Major adverse cardiovascular events developed within the follow-up period were recorded. The time in the therapeutic range of each patient was calculated. The presence of left ventricular thrombus beyond 180 days despite warfarin usage was classified as persistent left ventricular thrombus.The study included 174 subjects (169 males and 5 females). The mean age of the study population was 54.5 ± 11.0 years. The number of patients in whom the left ventricular thrombus resolved with treatment in less than 180 days was 56 (32.2%). Median anticoagulation time in the study population was 252 [150-480] days and the meantime in the therapeutic range of the patients was 54 ± 19%. The time in therapeutic range value of the groups was similar (P=.593). It was found that concomitant clopidogrel use (P=.003) and left ventricular thrombus area (P < .001) were the independent predictors of left ventricular thrombus resolution within less than 180 days in the logistic regression analysis.Concomitant use of clopidogrel was found to be associated with left ventricular thrombus resolution but left ventricular thrombus size was related to left ventricular thrombus persistency. Although standard 3-6 months of anticoagulation is advised for left ventricular thrombus, considering the presence of these predictors in such patients may guide the physicians to individualize the treatment.

Virtual Education for Patient Self-Testing for Warfarin Therapy Is Effective During the COVID-19 Pandemic.

BackgroundPrior to the COVID-19 pandemic, warfarin users were required to complete in-person training in order to participate in approved international normalized ratio (INR) patient self-testing (PST) programs. To minimize in-person contact during the pandemic, a federal waiver of the in-person training requirement allowed new patients to begin PST after completing virtual training. However, it was uncertain whether such patients achieved comparable levels of INR control to patients receiving in-person training.MethodsINR results for patients receiving virtual training upon PST commencement between April 1, 2020, and December 31, 2020, were compared to those of patients initiating PST with in-person training between April 1, 2019, and December 31, 2019. The primary outcome was the difference in warfarin time in therapeutic range (TTR) between the groups, with secondary outcomes including differences in the percentages of INR values within individually prescribed INR range and of critical INR values.ResultsThe records of 33,683 patients were included in the analysis (13,568 in the “In-Person” sample; 20,115 in the “Virtual” sample). Patients in the Virtual sample achieved a TTR of 66.78%, compared to the In-Person sample (64.19%; absolute difference 2.59; 95% confidence interval [CI] = 2.50–2.68, p < 0.001). The TTR values were also statistically significantly higher in all subgroups evaluated across categories of patient age, gender, geography, and indication. Similarly favorable results were achieved for INR values in range and critical values.ConclusionVirtual education for PST for warfarin therapy is effective and should continue to be an option for patients and providers throughout the pandemic, and possibly beyond.

The Effect of Serum Magnesium Level on Stable Anticoagulation in Patients Using Warfarin for Various Cardiac Indications.

Warfarin is a vitamin K antagonist agent that inhibits clotting factors used for long-term anticoagulation. Time in therapeutic range (TTR) in patients using warfarin is one of the primary treatment effectiveness requirements. We aim to investigate the relationship between serum magnesium levels, the international normalized ratio (INR) values, and TTR values in people using warfarin for various indications. Our study is a single-center, cross-sectional, and retrospective study that included 169 patients between 18 and 70 who used warfarin for various indications. Demographic data, biochemical analysis, and coagulation parameters, including TTR calculation, were evaluated for all patients. Those with a TTR value below 60 were defined as labile INR, and those with 60 and above as stable INR group and compared. The mean INR value was higher in the labile INR group than the stable INR group (3.7 ± 2.9, 3.2 ± 0.3, respectively; p = 0.030). The Mg values are significantly lower in the labile INR group than the stable group (1.8 ± 0.2mg/dL, 2.0 ± 0.1mg/dL, respectively; p < 0.001). In binary multivariate logistic regression analysis, magnesium value was the most influential INR stabilization factor (p < 0.001). As a result of our study, it was concluded that magnesium levels are an influential factor in stabilizing INR. We can state that we have contributed to the literature and can be a reference for future studies.

The effect of COVID-19 pandemic on time in therapeutic range in patients using warfarin

Introduction: Patients receiving anticoagulant therapy experience a serious problem at a time when the rates of outpatient visits for the international normalized ratio (INR) monitoring are gradually decreasing owing to the risk of virus transmission during the pandemic. The aim of this multicenter study was to investigate how the coronavirus disease 2019 pandemic affected the time in therapeutic range (TTR) value, which shows the use of effective doses of warfarin, and its monitoring in patients using warfarin. Materials and Methods: A total of 158 patients with 3 consecutive prepandemic INR levels and at least 3 postpandemic INR levels without time limitation were retrospectively evaluated. TTR values were calculated and the preepidemic and postepidemic values were compared. TTR was obtained using the conventional method. Results: The mean preepidemic and postepidemic TTR values were found to be 64.4 (61.8%–67.0%) and 34.9 (30.8%–39.0%), respectively. TTR rate was statistically significantly lower in the postpandemic period than in the prepandemic period (P < 0.001). While the prepandemic TTR of 68 (43%) patients was <60, the postpandemic TTR of 125 (79%) patients was <60. Discussion and Conclusion: Patients using warfarin were found to have lower TTR values during the pandemic. One of the most important reasons for this result is patients' delayed admission to the hospital due to fear of infection. The importance of regular follow-ups and alternative solutions should be emphasized for the effective treatment of these patients.

Time in Therapeutic Range (TTR) and the Efficacy of Anticoagulant Therapy in Preventing Thromboembolism in Cardiac Patients Receiving Warfarin at Shifa Medical Complex: A Cross-Sectional Study

Background: Anticoagulant control is assessed by Time in Therapeutic Range (TTR). For a given patient, TTR is defined as the duration of time in which the patient’s International Normalized Ratio (INR) values were within a desired range. Aim: To assess TTR in patients receiving anticoagulant treatment and the efficacy of Anticoagulant therapy in preventing Thromboembolism in Cardiac Patients receiving Warfarin for atrial fibrillation and with high CHADS VASC score, valvular and non-valvular heart disease at a referral center for cardiovascular diseases at Gaza Shifa Medical Complex, Palestine. Materials and Method: Over 8 months, we enrolled eligible patients presenting to Shifa Medical Complex in Gaza for regular INR testing. Demographic data, medical history, and current medications were determined for all participants. TTR was assessed by both tradition and cross-sectional methods. Results: A total of 46 patients (mean age 57.15±12.6 years, 50% women) underwent 230 INR measurements. The mean TTR was calculated as 50.86±21.37%. Participants of this study were assessed for their risk of having stroke using CHADS VASC score and risk of bleeding using HAS BLED score. Risk of stroke was significantly higher for females (P= 0.031). Of the sample patients, 47.8% were in the good control category (TTR &gt;60%), and 52.2% were in the poor control category (TTR &lt;60%). The mean TTR of the studied patients (54.9%) was below the good control range.There were 12 participants had thromboembolism of patients with low traditional TTR. This was statistically significant, TTR with occurrence of thromboembolism, (P= 0.001). Conclusion: We found a mean TTR of 50.86% among study patients diagnosed with atrial fibrillation and high CHADS VASC score, valvular and non - valvular heart disease who were receiving warfarin therapy. None of the risk factor was significantly related to low TTR values among study participants. The study showed the low TTR was associated with increased risk of thromboembolism among participants in this study. Moreover, showed the superiority of tradition TTR over cross-sectional TTR in evaluating anticoagulant therapy.

Time in therapeutic range values of patients using warfarin and factors that influence time in therapeutic range.

The time in therapeutic range (TTR) of international normalized ratio (INR) is essential for the safety and efficacy of warfarin treatment. In this study, we aimed to determine TTR and the factors that affect TTR in patients using warfarin. Patients taking warfarin for valvular and nonvalvular atrial fibrillation (AF) or prosthetic heart valves who were admitted to our cardiology outpatient clinic were enrolled. TTR was calculated using the linear interpolation method. The patients were analyzed according to warfarin indications and TTR efficiency (TTR ≥60%). Weekly warfarin dose, the duration of warfarin use, the frequency of INR visits per year, and the awareness of patients regarding target INR were noted. The TTR of 248 patients (aged 57.21±12.45 years, 33.1% male) was 55.92±27.84%, and 48.0% patients exhibited efficient TTR. Clinical and demographic characteristics (age, sex, socioeconomic status, and comorbidities) exerted no effect on TTR and TTR efficiency. The frequency of INR visits per year was 10.02±3.80. TTR was related to the frequency of annual INR visits (r=0.131, p=0.039). Only one-third (30.2%) of patients were aware of their target INR. The literacy of the patients and duration of warfarin use exerted a positive effect on awareness (p=0.011 and p=0.024, respectively). The findings of our study demonstrated that TTR and TTR efficiency were low and not associated with the characteristics of patients or indications. Unfortunately, in patients with valvular AF and prosthetic valves, warfarin is the sole drug that can be used. Thus, awareness and knowledge regarding target INR are essential to overcome poor anticoagulation monitoring with frequent INR visits.

Varfarin Tedavisi Alan Serebrovasküler Hastalığı Olan Hastalarda Terapötik Aralıkta Olma Oranlarının Değerlendirilmesi

Objective: The efficacy of warfarin therapy correlates with the Time in Therapeutic Range (TTR). This study aimed to investigate the efficacy and target achievement rates in patients using warfarin who were followed up in stroke outpatient clinics. Methods: In this study, 103 patients who had been under warfarin treatment were retrospectively evaluated. Duration and indications for warfarin use, thrombotic or hemorrhagic complications were recorded. Target INR value was 3.0-3.5 in patients with mechanical valves and 2.0-3.0 in those using warfarin for other indications. Results: In this study, 103 patients with a mean age of 67.14±14.19, 47 men and 56 women, were included. Indications for warfarin use, respectively, were non-valvular atrial fibrillation (AF) in 61.6% of the patients, akinetic/hypokinetic segment on echocardiography (ECHO) in 12.62%, thrombophilia in 8.74%, metallic prosthetic valve in 3.88%, frequent transient ischemic attacks in 6.79%, a hypokinetic segment on ECHO with atrial fibrillation in 5.82% and vertebral artery dissection in 0.87%. 46.8% of the patients were determined to be in good control, with a mean TTR of 64.09%; also, TTR was 100% in 36.8% of them. Minor/major hemorrhagic event was noted in 10 patients (9.70%), two of whom had an intracerebral hemorrhage. Conclusion: The mean TTR value detected in this study is considerably higher than the rate reported in our country. Findings of this study suggest that close monitoring is paramount of importance and vital in patients with stroke. Regular monitoring of stroke patients using warfarin will be beneficial in terms of informing patients, providing optimal anticoagulation and preventing complications.

The short-term effect of the COVID-19 pandemic on the management of warfarin therapy.

Aim The aim of this study was to investigate the short-term effect of the COVID-19 pandemic on the management of warfarin therapy used for atrial fibrillation (AF) and prosthetic valve disease.Material and methods The study included 139 Atrial fibrillation (AF) patients and 173 prosthetic valve patients (PVP) who were using warfarin. The time in therapeutic range (TTR), International Normalized Ratio (INR) averages, the numbers of INR tests, and the non-adherence to INR monitoring (NIM) were compared for the pre-covid period (PCP) and the COVID-19 period (CP). Also, adherence to warfarin therapy was evaluated with a questionnaire.Results For all patients, the INR values were higher in the CP (2.47 vs 2.60, p&lt;0.001), and the NIM percentage was higher (19.2 % vs 71.5 %, p&lt;0.001) in the CP. The number of INR tests was lower during the CP (p&lt;0.001).The percentage of patients with TTR≥70 % was lower during the CP (41.7 % vs 33 % p=0.017). Subgroup analysis showed that for PVP, TTR values and the percentage of patients with TTR ≥70 % were similar in both the PCP and CP periods. The questionnaire showed that for 94.1 % of respondents, the major cause of NIM in the CP was the COVID-19 pandemic. However, during the CP, adherence to warfarin medication was high (95.5 %).Conclusion Lower TTR during the COVID-19 pandemic can increase bleeding and thromboembolic cases.Therefore, patients taking warfarin should be followed more closely, and more practical ways should be considered for INR testing.

Many Good Reasons to Switch from Vitamin K Antagonists to Non-Vitamin K Antagonists in Patients with Non-Valvular Atrial Fibrillation.

Non-vitamin K oral anticoagulants (NOACs) are the first choice for prophylaxis of cardioembolism in patients with non-valvular atrial fibrillation (AF) who are anticoagulant-naïve, as well as the preferable anticoagulation strategy in those who are on vitamin K antagonists (VKAs), but with a low time in therapeutic range (TTR). Nonetheless, there are many good reasons to consider switching from VKAs to NOACs also when TTR is >70%. From the pharmacological standpoint, anticoagulation with VKAs may remain erratic even in those patients who have high TTR values, owing to the mode of action of this drug class. Furthermore, experimental data suggest that, unlike VKAs, NOACs favorably modulate the effects of factor Xa and thrombin in the cardiovascular system through the protease-activated receptor family. Clinically, the most striking advantage provided by NOACs over VKAs, irrespective of the TTR, is the substantially lower risk of intracranial hemorrhage. NOACs have also been associated with less deterioration of renal function as compared with VKAs and may confer protection against cardiovascular events not strictly related to AF, especially the acute complications of peripheral artery disease. In this narrative review, we discuss the evidence according to which it is warranted to systematically substitute NOACs for VKAs for the prevention of AF-related stroke and systemic embolism.

Evaluation of Bleeding Rate and Time in Therapeutic Range in Patients Using Warfarin Before and During the COVID-19 Pandemic-Warfarin Treatment in COVID-19.

The treatment process of patients using warfarin is expected to be hindered during the COVID-19 pandemic. Therefore we investigated whether the time in therapeutic range (TTR) and bleeding complications were affected during the COVID-19 pandemic. 355 patients using warfarin were included between March 2019 to March 2021. Demographic parameters, INR (international normalized ratio), and bleeding rates were recorded retrospectively. The TTR value was calculated using Rosendaal’s method. The mean age of the patients was 61 ± 12 years and 55% of them were female. The mean TTR value during the COVID-19 pandemic was lower than the pre-COVID-19 period (56 ± 21 vs 68 ± 21, P < 0.001). Among the patients, 41% had a lack of outpatient INR control. During the COVID-19 pandemic, 71 (20%) patients using VKA suffered bleeding. Among patients with bleeding, approximately 60% did not seek medical help and 6% of patients performed self-reduction of the VKA dose. During the COVID-19 pandemic, TTR values have decreased with the lack of monitoring. Furthermore, the majority of patients did not seek medical help even in case of bleeding.

Which is the best for the warfarin monitoring: Following up by fixed or variable physician?

Objective:Warfarin therapy has some difficulties in terms of close monitoring and dosage. This study aims to evaluate the effect of same-fixed versus different-variable physician-based monitoring of warfarin therapy on treatment quality and clinical end-points.Methods:A total of 625 consecutive patients requiring warfarin treatment were enrolled at seven centers. INR values of the patients measured at each visit and registered to hospital database were recorded. Time in therapeutic range (TTR) was calculated using linear interpolation method (Rosendaal’s method). A TTR value of ≥65% was considered as effective warfarin treatment. If a patient was evaluated by the same-fixed physician at each INR visit, was categorized into the same-physician (SP) group. In contrast, if a patient was evaluated by different-variable physicians at each INR visit, was categorized into variable physician (VP) group. Enrolled patients were followed up for bleeding and embolic events.Results:One hundred and fifty-six patients (24.9%) were followed by SP group, 469 (75.1%) patients were followed by VP group. Median TTR value of the VP group was lower than that of SP group (56.2% vs. 65.1%, respectively, p=0.009). During median 25.5 months (9–36) of follow-up, minor bleeding, major bleeding and cerebral embolic event rates were higher in VP group compared to SP group (p<0.001, p=0.023, p<0.001, respectively). In multivariate analysis, INR monitoring by VP group was found to be an independent predictor of increased risk of bleeding events (OR 2.55, 95% CI 1.64–3.96, p<0.001) and embolism (OR 3.42, 95% CI 1.66–7.04, p=0.001).Conclusion:INR monitoring by same physician was associated with better TTR and lower rates of adverse events during follow-up. Hence, it is worth encouraging an SP-based outpatient follow-up system at least for where warfarin therapy is the only choice.

SAMe-TT2R2 in tunisian population: Results from the NATURE AF registry

Identifying patients who are likely to achieve and maintain a therapeutic international normalized ratio when prescribed a vitamin K antagonist (VKA) for stroke prevention in atrial fibrillation (AF) is challenging. The SAMe-TT 2 R 2 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. Our objective was to validate this score in a nationwide cohort of non-valvular AF patients. We studied a cohort of consecutive Tunisian patients with non-valvular AF who had oral anticoagulation. The baseline and 6-months SAMe-TT2R2 score was calculated. We included 915 patients, of whom 440 (48.1%) were male. Their median age was 65 years, median Cardiac failure or dysfunction, Hypertension, Age over 75 years [Doubled], Diabetes, Stroke [Doubled] - Vascular disease, Age between 65–74 and Sex category [Female] (CHA2DS2-VASc) score was 2 (0–9), and median Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly (HAS-BLED) score was 1 (0–5). The median SAME-TT2R2 score was 2 (0–8). At 12 months, the mean ± standard deviation time in therapeutic range was 48.9% ± 28.7% overall, and 110 patients (12.0%) had a time in therapeutic range value > 65%. Patients with a SAME-TT2R2 score 0 to 1 had a mean time in therapeutic range of 49.3% ± 30.4%, whereas patients with a SAME-TT2R2 score ≥ 2 had a mean time in therapeutic range of 48.7% ± 28.0% ( P 0.871). The odds ratio for having a low time in therapeutic range value was 1 (95% confidence interval, 0.9–1.0; P 0.871) for those patients with a SAME-TT2R2 score ≥ 2. In a “real-world” cohort of patients with atrial fibrillation and oral anticoagulation with VKA, there was no clinical value evidence of the SAME-TT2R2 score for the identification of patients who would have poor-quality anticoagulation.