Efficacy of human prothrombin complex concentrate in the treatment of warfarin overdose in patients receiving warfarin for mechanical heart valve replacement.

Warfarin, a widely utilized anticoagulant, is paramount for preventing thromboembolic events in patients with mechanical heart valve replacements. However, its narrow therapeutic index can lead to over-anticoagulation and overdose, resulting in serious health risks. This study examines the efficacy of human prothrombin complex concentrate (PCC) in managing warfarin overdose, in comparison with traditional treatments. A retrospective analysis was conducted on 162 adults who presented with warfarin overdose (INR > 5.0) at a tertiary care hospital between 2016 and 2020. Participants were divided into 2 groups-those treated with PCC (n = 57) and those treated with conventional methods (n = 105), including vitamin K and fresh frozen plasma. The primary outcome was the rate of reaching the target (International Normalized Ratio) INR within 24 hours. Secondary outcomes included transfusion requirements, thromboembolic events, adverse reactions, 30-day mortality, and length of hospital stay. PCC demonstrated significant efficacy, with 89.5% of patients achieving the target INR within 24 hours, compared to 64.8% in the control group (P < .05). The PCC group also had reduced transfusion requirements and a shorter average hospital stay. There was no significant difference in thromboembolic events or adverse reactions between the 2 groups, and the reduced 30-day mortality in the PCC group was not statistically significant. Human prothrombin complex concentrate is associated with rapid reaching the target INR, decreased transfusion needs, and shortened hospitalization, making it a promising option for warfarin overdose management. While the results are encouraging, larger, multicenter, randomized controlled trials are necessary to further validate these findings and optimize PCC administration protocols.

Abnormal coagulation after hepatectomy in patients with normal preoperative coagulation function.

BACKGROUND: To explore the risk factors for postoperative abnormal coagulation (PAC) and establish a predictive model for patients with normal preoperative coagulation function who underwent hepatectomy. MATERIALS AND METHODS: A total of 661 patients with normal preoperative coagulation function who underwent hepatectomy between January 2015 and December 2021 at the First Affiliated Hospital of Sun Yat-sen University were divided into two groups: the postoperative abnormal coagulation group (PAC group, n = 362) and the normal coagulation group (non-PAC group, n = 299). Univariate and multivariate logistic analyses were used to identify the risk factors for PAC. RESULTS: The incidence of PAC in 661 patients who underwent hepatectomy was 54.8% (362/661). The least absolute shrinkage and selection operator (LASSO) method was used for multivariate logistic regression analysis. The preoperative international normalized ratio (INR), intraoperative succinyl gelatin infusion and major hepatectomy were found to be independent risk factors for PAC. A nomogram for predicting the PAC after hepatectomy was constructed. The model presented a receiver operating characteristic (ROC) curve of 0.742 (95% confidence interval (CI): 0.697-0.786) in the training cohort. The validation set demonstrated a promising ROC of 0.711 (95% CI: 0.639-0.783), and the calibration curve closely approximated the true incidence. Decision curve analysis (DCA) was performed to assess the clinical usefulness of the predictive model. The risk of PAC increased when the preoperative international normalized ratio (INR) was greater than 1.025 and the volume of intraoperative succinyl gelatin infusion was greater than 1500 ml. CONCLUSION: The PAC is closely related to the preoperative INR, intraoperative succinyl gelatin infusion and major hepatectomy. A three-factor prediction model was successfully established for predicting the PAC after hepatectomy.

Pharmacogenetic guided versus standard warfarin dosing for routine clinical care with its pharmacoeconomic impact: a randomized controlled clinical trial.

BACKGROUND: Empirical use of pharmacogenetic test(PGT) is advocated for many drugs, and resource-rich setting hospitals are using the same commonly. The clinical translation of pharmacogenetic tests in terms of cost and clinical utility is yet to be examined in hospitals of low middle income countries (LMICs). AIM: The present study assessed the clinical utility of PGT by comparing the pharmacogenetically(PGT) guided- versus standard of care(SOC)- warfarin therapy, including the health economics of the two warfarin therapies. METHODS: An open-label, randomized, controlled clinical trial recruited warfarin-receiving patients in pharmacogenetically(PGT) guided- versus standard of care(SOC)- study arms. Pharmacogenetic analysis of CYP2C9*2(rs1799853), CYP2C9*3(rs1057910) and VKORC1(rs9923231) was performed for patients recruited to the PGT-guided arm. PT(Prothrombin Time)-INR(international normalized ratio) testing and dose titrations were allowed as per routine clinical practice. The primary endpoint was the percent time spent in the therapeutic INR range(TTR) during the 90-day observation period. Secondary endpoints were time to reach therapeutic INR(TRT), the proportion of adverse events, and economic comparison between two modes of therapy in a Markov model built for the commonest warfarin indication- atrial fibrillation. RESULTS: The study enrolled 168 patients, 84 in each arm. Per-protocol analysis showed a significantly high median time spent in therapeutic INR in the genotype-guided arm(42.85%; CI 21.4-66.75) as compared to the SOC arm(8.8%; CI 0-27.2)(p < 0.00001). The TRT was less in the PG-guided warfarin dosing group than the standard-of-care dosing warfarin group (17.85 vs. 33.92 days) (p = 0.002). Bleeding and thromboembolic events were similar in the two study groups. Lifetime expenditure was ₹1,26,830 in the PGT arm compared to ₹1,17,907 in the SOC arm. The QALY gain did not differ in the two groups(3.9 vs. 3.65). Compared to SOC, the incremental cost-utility ratio was ₹35,962 per QALY gain with PGT test opting. In deterministic and probabilistic sensitivity analysis, the base case results were found to be insensitive to the variation in model parameters. In the cost-effectiveness-acceptability curve analysis, a 90% probability of cost-effectiveness was reached at a willingness-to-pay(WTP) of ₹ 71,630 well below one time GDP threshold of WTP used. CONCLUSION: Clinical efficacy and the cost-effectiveness of the warfarin pharmacogenetic test suggest its routine use as a point of care investigation for patient care in LMICs.

Warfarin dosage in a postpartum woman while breastfeeding: A case report.

Warfarin is the only oral anticoagulant recommended in women who are breastfeeding. Although warfarin is a compatible and recommended agent in the postpartum period and during lactation, little is known regarding changes to warfarin dose requirements in this patient population. Here, we report the case of a 40-year-old woman who transitioned from enoxaparin monotherapy back to warfarin at 2 months postpartum, while she was breastfeeding. Despite resuming warfarin at her previously therapeutic dose, her international normalized ratio (INR) remained subtherapeutic and required multiple dose increases. She ultimately required a 100% increase in her warfarin dose postpartum, compared to pre-pregnancy, to achieve a therapeutic INR. This case suggests patients may require higher warfarin doses postpartum, compared to pre-pregnancy, especially if breastfeeding. Clinicians should closely monitor these patients and adjust warfarin doses as necessary.

International Normalized Ratio Predicts Recurrence and Bleeding in Patients With Acute Venous Thromboembolism Who Undergo Direct Oral Anticoagulants.

Prothrombin time/international normalized ratio (PT/INR) is related to both antithrombotic effect and risk of bleeding. Its role in the prediction of venous thromboembolism (VTE) recurrence and bleeding for patients with acute VTE who undergo direct oral anticoagulants (DOACs) treatment is unclear, despite previous studies revealed some association between them. The predictive efficiency of INR for VTE recurrence and bleeding were analyzed in a retrospective cohort with VTE patients who underwent DOACs treatment. Then its predictive efficiency for VTE recurrence and bleeding were validated in a prospective cohort with the acquired cutoffs range, and compared with anti-Xa level, DASH and VTE-BLEED scores. In the retrospective cohort (n = 1083), the sensitivity and specificity of INR for the prediction of VTE recurrence were 79.4% and 92.8%, respectively. The area under the curve (AUC) was 0.881 (0.803-0.960)(P = .025). The cutoff value of INR was 0.9. The sensitivity and specificity of INR for the prediction of bleeding were 85.7% and 77.9%, respectively. The AUC was 0.876 (0.786-0.967)(P < .001). The cutoff value of INR was 2.1. In the prospective cohort (n = 202), the calibration showed that there were 4 (50%) patients with VTE recurrence, 156 (97.5%) patients with non-recurrence and bleeding (non-R&B), and 20 (58.8%) patients with bleeding in the low (INR < 0.9)(n = 8), intermediate (0.9 ≤ INR ≤ 2.1)(n = 160), and high (INR > 2.1)(n = 34) groups, respectively. The baseline PT/INR value at the initiation of DOACs treatment is an independent predictor for VTE recurrence and bleeding in patients with acute VTE who undergo DOACs treatment.

The Relationship Between Preoperative International Normalized Ratio and Postoperative Major Bleeding in Total Shoulder Arthroplasty.

INTRODUCTION: This study aimed to assess the relationship between preoperative international normalized ratio (INR) levels and major postoperative bleeding events after total shoulder arthroplasty (TSA). METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried for TSA from 2011 to 2020. A final cohort of 2405 patients with INR within 2 days of surgery were included. Patients were stratified into four groups: INR ≤ 1.0, 1.0 < INR ≤ 1.25, 1.25< INR ≤ 1.5, and INR > 1.5. The primary outcome was bleeding requiring transfusion within 72 hours, and secondary outcome variables included complication, revision surgery, readmission, and hospital stay duration. Multivariable logistic and linear regression analyses adjusted for relevant comorbidities were done. RESULTS: Of the 2,405 patients, 48% had INR ≤ 1.0, 44% had INR > 1.0 to 1.25, 7% had INR > 1.25 to 1.5, and 1% had INR > 1.5. In the adjusted model, 1.0 < INR ≤ 1.25 (OR 1.7, 95% CI 1.176 to 2.459), 1.25 < INR ≤ 1.5 (OR 2.508, 95% CI 1.454 to 4.325), and INR > 1.5 (OR 3.200, 95% CI 1.233 to 8.302) were associated with higher risks of bleeding compared with INR ≤ 1.0. DISCUSSION: The risks of thromboembolism and bleeding lie along a continuum, with higher preoperative INR levels conferring higher postoperative bleeding risks after TSA. Clinicians should use a patient-centered, multidisciplinary approach to balance competing risks.

Anticoagulation control among patients on vitamin K antagonists in nine countries in Sub-Saharan Africa.

Vitamin K antagonists (VKA) is the primary anticoagulant in most settings of Sub-Saharan Africa. Understanding the quality of anticoagulation services in the continent is vital in optimising the intended benefits. This study assessed the quality of anticoagulation and associated factors among VKA-treated patients in nine SSA countries. We conducted a retrospective cohort study of randomly selected patients on anticoagulation from 20 clinics in Botswana, the Democratic Republic of Congo, Ethiopia, Gambia, Ghana, Mozambique, Nigeria, Tanzania, and South Africa. Eligible participants were those on VKAs for at least three months and with at least four international normalised ratios (INR) results in 2019-2021. We report the proportion of INR values in the therapeutic range, time-in-therapeutic range (TTR) using the Rosendaal method, and the proportion of patients with TTR ≥ 65% (optimal anticoagulation). The mean age was 51.1(16.1) years, and 64.2% were women. The most common indications for VKA included venous thromboembolism (29.6%), prosthetic valves (26.7%) and atrial fibrillation/flutter (30.1%). We analysed 6743 INR tests from 1011 participants, and of these, 48.5% were sub-therapeutic, 34.1% therapeutic, and 17.4% were supratherapeutic relative to disease-specific reference ranges. TTR was calculated for 660 patients using 4927 INR measurements. The median (interquartile range [IQR]) TTR was 35.8(15.9,57.2) %. Optimal anticoagulation control was evident in 19.2% of participants, varying from 2.7% in Tanzania to 23.1% in Ethiopia. The proportion of patients with TTR ≥ 65% was 15,4% for prosthetic heart valves, 21.1% for venous thromboembolism and 23.7% for atrial fibrillation or flutter. Countries with universal health coverage had higher odds of optimal anticoagulation control (adjusted odds ratio (aOR) 1.79, 95% confidence interval [CI], 1.15- 2.81, p = 0.01). Patients on VKAs for different therapeutic indications in SSA had suboptimal TTR. Universal health coverage increased the odds of achieving TTR by 79%. The evidence calls for more intensive warfarin management strategies in SSA, including providing VKA services without out-of-pocket payments.

Effect of Reduced INR in Early Pregnancy on the Occurrence of Preeclampsia: A Retrospective Cohort Study.

To investigate the effect of reduced early-pregnancy activated partial thrombin time (APTT), prothrombin time (PT), and international standardized ratio (INR) on the risk of preeclampsia. A total of 8549 pregnant women with singleton births were included. Early pregnancy APTT, PT, and INR levels, with age, birth, prepregnancy body mass index, fibrinogen (FBG), thrombin time (TT), D-dimer (DD2), antithrombin III (ATIII), fibrin degradation products (FDP) as confounders, generalized linear model of APTT, the relative risk of PT and INR when INR reduction. After adequate adjustment for confounders, the relative risk of preeclampsia was 0.703 for every 1 s increase in plasma PT results in early pregnancy, and for every 0.1 increase in plasma INR results, the relative risk of preeclampsia was 0.767. With a PT less than the P25 quantile (<11 s), the relative risk of preeclampsia was 1.328. The relative risk of preeclampsia at an INR less than the P25 quantile (<0.92) was 1.24. There was no statistical association between APTT on the risk of preeclampsia. The relative risk of preeclampsia is strongly associated with a decrease in PT and INR in early pregnancy. PT and INR in early pregnancy were a potential marker in the risk stratification of preeclampsia. Focusing on reduced PT and INR levels in early pregnancy can help to identify early pregnancies at risk for preeclampsia.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

A Randomized Trial Comparing Standard of Care to Bayesian Warfarin Dose Individualization.

The quality of warfarin treatment may be improved if management is guided by the use of models based upon pharmacokinetic-pharmacodynamic theory. A prospective, two-armed, single-blind, randomized controlled trial compared management aided by a web-based dose calculator (NextDose) with standard clinical care. Participants were 240 adults receiving warfarin therapy following cardiac surgery, followed up until the first outpatient appointment at least 3 months after warfarin initiation. We compared the percentage of time spent in the international normalized ratio acceptable range (%TIR) during the first 28 days following warfarin initiation, and %TIR and count of bleeding events over the entire follow-up period. Two hundred thirty-four participants were followed up to day 28 (NextDose: 116 and standard of care: 118), and 228 participants (114 per arm) were followed up to the final study visit. Median %TIR tended to be higher for participants receiving NextDose guided warfarin management during the first 28 days (63 vs. 56%, P = 0.13) and over the entire follow-up period (74 vs. 71%, P = 0.04). The hazard of clinically relevant minor bleeding events was lower for participants in the NextDose arm (hazard ratio: 0.21, P = 0.041). In NextDose, there were 89.3% of proposed doses accepted by prescribers. NextDose guided dose management in cardiac surgery patients requiring warfarin was associated with an increase in %TIR across the full follow-up period and fewer hemorrhagic events. A theory-based, pharmacologically guided approach facilitates higher quality warfarin anticoagulation. An important practical benefit is a reduced requirement for clinical experience of warfarin management.

Medical History and Preoperative Coagulation Profile as Predictors of Outcomes in Elective Spinal Surgery: A Meta-Analysis.

BACKGROUND: In patients with unremarkable medical history, comprehensive preoperative hemostasis screening in elective neurosurgery remains debated. Comprehensive medical history has shown to be noninferior to coagulation profile to evaluate surgical outcomes. This study aims to evaluate the predictiveness of preoperative coagulation screening and medical history for surgical outcomes. METHODS: Databases were searched until April 2023 for observational cohort studies that reported preoperative hemostasis screening and clinical history prior to elective neurosurgical procedures. Outcomes of interest included postoperative transfusion, mortality, and complications. Pooled relative risk ratios (RRs) were analyzed using random-effects models. RESULTS: Out of 604 studies, 3 cohort studies met our inclusion criteria, adding a patient population of 83,076. Prolonged partial thromboplastin time (PTT; RR=1.42, 95% confidence interval [CI] =1.14, 1.77, P=0.002), elevated international normalized ratio (INR; RR=2.01, 95% CI=1.14, 3.55, P=0.02), low platelet count (RR=1.58, 95% CI=1.34, 1.86, P<0.00001), and positive bleeding history (RR=2.14, 95% CI=1.16, 3.93, P=0.01) were associated with postoperative transfusion risk. High PTT (RR=2.42, 95% CI=1.24, 4.73, P=0.010), High INR (RR=8.15, 95% CI=5.97, 11.13; P<0.00001), low platelet count (RR=4.89, 95% CI=3.73, 6.41, P<0.00001), and bleeding history (RR=7.59, 95% CI=5.84, 9.86, P<0.00001) were predictive of mortality. Prolonged PTT (RR=1.53, 95% CI=1.25, 1.86, P=<0.0001), a high INR (RR=3.41, 95% CI=2.63, 4.42, P=< 0.00001), low platelets (RR=1.63, 95% CI=1.40, 1.90, P=<0.00001), and medical history (RR=2.15, 95% CI=1.71, 2.71, P=<0.00001) were predictive of complications. CONCLUSIONS: Medical history was a noninferior predictor to coagulation profile for postoperative transfusion, mortality, and complications. However, our findings are mostly representative of elective spinal procedures. Cost-effective alternatives should be explored to promote affordable patient care in patients with unremarkable history.

Utilizing the International Normalized Ratio-Platelet Index for Predicting Hospital Outcomes After Spontaneous Supratentorial Intracerebral Hemorrhage.

OBJECTIVE: Spontaneous intracerebral hemorrhage (ICH) poses a public health issue due to its elevated mortality rates. The International Normalized Ratio-platelet index (INR-Plt index) has recently been recognized as a predictive factor for liver disease progression. The potential of applying the INR-Plt index in forecasting ICH prognosis presents an intriguing subject. This study endeavors to examine the correlation between the INR-Plt index and hospital outcomes in patients with spontaneous supratentorial ICH. METHODS: A retrospective examination of 283 adult ICH patients was undertaken. The INR-Plt index was computed using the formula: [INR/platelet counts (1000/µL)] × 100. The clinical outcomes evaluated consisted of mortality rates and the Modified Rankin Scale (mRS) at discharge. An unfavorable outcome was defined as an mRS score from 4 to 6. RESULTS: The study found a significant correlation between the INR-Plt index and hospital mortality (odds ratio: 4.31, 95% CI: 1.07-17.31, P = 0.04). There was a 43% rise in mortality risk for every 0.1 unit increase in the INR-Plt index. Kaplan-Meier survival curves illustrated a considerably lower survival rate at discharge for patients with an INR-Plt index >0.8 (log-rank test: P = 0.047). Regarding unfavorable outcomes, the INR-Plt index was not a significant factor according to logistic regression analyses. CONCLUSIONS: The INR-Plt index is a predictor of hospital mortality in patients with spontaneous supratentorial ICH. A higher INR-Plt index value is associated with an increased risk of mortality, underlining the potential usefulness of this composite index in guiding clinical decision-making and enabling risk stratification.

The Utilisation of INR to identify coagulopathy in burn patients.

Studies conflict on the significance of burn-induced coagulopathy. We posit that burn-induced coagulopathy is associated with injury severity in burns. Our purpose was to characterize coagulopathy profiles in burns and determine relationships between % total burn surface area (TBSA) burned and coagulopathy using the International Normalized Ratio (INR). Burned patients with INR values were identified in the TriNetX database and analyzed by %TBSA burned. Patients with history of transfusions, chronic hepatic failure, and those on anticoagulant medications were excluded. Interquartile ranges for INR in the burned study population were 1.2 (1.0-1.4). An INR of ≥ 1.5 was used to represent those with burn-induced coagulopathy as it fell outside the 3rd quartile. The population was stratified into subgroups using INR levels <1.5 or ≥1.5 on the day of injury. Data are average ± SD analyzed using chi-square; p < .05 was considered significant. There were 7,364 burned patients identified with INR <1.5, and 635 had INR ≥1.5. Comparing TBSA burned groups, burn-induced coagulopathy significantly increased in those with ≥20% TBSA; p = .048 at 20-29% TBSA, p = .0005 at 30-39% TBSA, and p < .0001 for 40% TBSA and above. Age played a significant factor with average age for those with burn-induced coagulopathy 59 ± 21.5 years and 46 ± 21.8 for those without (p < .0001). After matching for age, TBSA, and demographics, the risk of 28 day-mortality was higher in those with burn-induced coagulopathy compared to those without (risk difference 20.9%, p < .0001) and the odd ratio with 95% CI is 4.45 (3.399-5.825). Investigation of conditions associated with burn-induced coagulopathy showed the effect of heart diseases to be significant; 53% of patients with burn-induced coagulopathy had hypertension (p < .0001). Burn-induced coagulopathy increases with %TBSA burned. The information gained firmly reflects a link between %TBSA and burn-induced coagulopathy, which could be useful in prognosis and treatment decisions.

Plasma: indications, controversies, and opportunities.

Plasma is overused as a blood product worldwide; however, data supporting appropriate use of plasma is scant. Its most common utilization is for treatment of coagulopathy in actively bleeding patients; it is also used for coagulation optimization prior to procedures with specific coagulation profile targets. A baseline literature review in PUBMED and Google Scholar was done (1 January 2000 to 1 June 2023), utilizing the following search terms: plasma, fresh frozen plasma, lyophilized plasma, indications, massive transfusion protocol, liver disease, warfarin reversal, cardiothoracic surgery, INR < 2. An initial review of the titles and abstracts excluded all articles that were not focused on transfusional medicine. Additional references were obtained from citations within the retrieved articles. This narrative review discusses the main indications for appropriate plasma use, mainly coagulation factor replacement, major hemorrhage protocol, coagulopathy in liver disease, bleeding in the setting of vitamin K antagonists, among others. The correlation between concentration of coagulation factors and INR, as well as the proper plasma dosing with its volume being weight-based, is also discussed. A high value approach to plasma utilization is supported with a review of the clinical situations where plasma is overutilized or unnecessary. Finally, a discussion of novel plasma products is presented for enhanced awareness.

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

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

The Acute Effect of Chamomile Intake on Blood Coagulation Tests in Healthy Volunteers: A Randomized Trial.

BACKGROUND: Chamomile administration may have desirable effects in the perioperative setting. Current practice, however, discourages perioperative chamomile use due to a theoretical increase in bleeding. Therefore, we evaluated if chamomile acutely (within 4 h of ingestion) prolongs coagulation assays. METHODS: Eight healthy volunteers were randomized to receive 2 interventions in a crossover design: (a) single dose of chamomile extract capsule (500 mg) and (b) single dose of chamomile tea (3 g in 150 mL water). Interventions were separated at least 3 days apart from each other. Blood was sampled pre-ingestion, 2 h post-ingestion, and 4 h post-ingestion for each intervention. The primary outcome was the maximal change in prothrombin time (PT) before vs after each intervention. Secondary outcomes included changes in international normalized ratio, activated partial thromboplastin time, thrombin time, reptilase time, and fibrinogen levels. RESULTS: All 8 subjects completed the study. The average pre-ingestion PT values for tea and capsules were 11.9 (1.1) s and 12.0 (0.9) s, respectively. Tea significantly increased the average maximum PT by 0.7 (0.2) s (P = 0.0078). Extract capsules increased the maximum PT by 0.3 (0.2) s (P = 0.06). Neither PT prolongation met the predefined 10% threshold for clinical significance. No significant changes in secondary outcomes were observed. CONCLUSIONS: Chamomile tea ingestion prolongs PT. However, the clinical significance of this is unclear at this time and warrants further investigation. ClinicalTrials.gov Registration Number: NCT05272475.

Fixed- Versus Variable-Dose Prothrombin Complex Concentrate for the Emergent Reversal of Vitamin K Antagonists: A Systematic Review and Meta-Analysis.

OBJECTIVES: Four-factor prothrombin complex concentrate (4-PCC) is recommended for rapid reversal of vitamin K antagonists (VKAs) such as warfarin, yet optimal dosing remains uncertain. DATA SOURCES: A systematic review was conducted of PubMed, Embase, and Ovid MEDLINE (Wolters Kluwer) databases from January 2000 to August 2023 for clinical studies comparing fixed- vs. variable-dose 4-PCC for emergent VKA reversal with at least one reported clinical outcome. STUDY SELECTION: Abstracts and full texts were assessed independently and in duplicate by two reviewers. DATA EXTRACTION: Data were extracted independently and in duplicate by two reviewers using predefined extraction forms. DATA SYNTHESIS: The analysis comprised three randomized trials and 16 cohort studies comprising a total of 323 participants in randomized trials (161 in fixed dosage and 162 in variable dosage) and 1912 patients in cohort studies (858 in fixed-dose and 1054 in variable dose). Extracranial bleeding was the predominant indication, while intracranial hemorrhage varied. Overall, a fixed-dose regimen may be associated with a lower dose of 4-PCC and results in a reduction in 4-PCC administration time compared with a variable-dose regimen. A fixed-dose regimen also likely results in increased clinical hemostasis. While there is no clear difference between the two regimens in terms of achieving a goal international normalized ratio (INR) less than 2, a fixed-dose regimen is less likely to achieve a goal INR less than 1.5. High certainty evidence indicates that the fixed-dose regimen reduces both mortality and the occurrence of thromboembolic events. Additional subgroup analyses provides exploratory data to guide future studies. CONCLUSIONS: A fixed-dose regimen for 4-PCC administration provides benefits over a variable-dose regimen in terms of dose reduction, faster administration time, improved clinical hemostasis, and reduced mortality and thromboembolic events. Further studies are warranted to better refine the optimal fixed-dose regimen.

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.

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.