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

Abstract 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

T-Peak to T-End Interval for Prediction of Positive Response to Ajmaline Challenge Test in Suspected Brugada Syndrome Patients

Background: Brugada syndrome (BrS) is diagnosed in patients with ST-segment elevation with coved-type morphology in the right precordial leads, occurring spontaneously or after provocative drugs. Due to electrocardiographic (ECG) inconsistency, provocative drugs, such as sodium-channel blockers, are useful for unmasking BrS. Ajmaline is superior to flecainide and procainamide to provoke BrS. Prolonged T-peak to T-end (TpTe) is associated with an increased risk of ventricular arrhythmia and sudden cardiac death in Brugada syndrome patients. Objective: This study aimed to investigate the predictive value of T-peak to T-end interval and corrected T-peak to T-end interval for predicting the positive response of the ajmaline challenge test in suspected Brugada syndrome patients. Methods: Patients who underwent the ajmaline test in our center were enrolled. Clinical characteristics and electrocardiographic parameters were analyzed, including TpTe, corrected TpTe, QT, corrected QT(QTc) interval, and S-wave duration, compared with the result of the ajmaline challenge test. Results: The study found that TpTe and corrected TpTe interval in suspected BrS patients were not significantly associated with a positive response to the ajmaline challenge test. Conclusions: The T-peak to T-end interval and corrected T-peak to T-end interval could not predict the positive response of the ajmaline challenge test in suspected Brugada syndrome patients

Cannabis and adverse cardiovascular events: A systematic review and meta-analysis of observational studies

Background: Cannabis is the most used illicit drug in the world. Global trends of decriminalization and legalization of cannabis lead to various forms of cannabis use and bring great concerns over adverse events, particularly in the cardiovascular (CV) system. To date, the association between cannabis and adverse CV events is still controversial. Purpose: We aim to conduct a systematic review and meta-analysis to assess the adverse CV events from cannabis use. Patients and methods: A systematic search for publications describing the adverse CV events of cannabis use, including acute myocardial infarction (MI) and stroke, was performed via PubMed, Scopus, and Cochrane Library databases. Data on effect estimates in individual studies were extracted and combined via random-effects meta-analysis using the DerSimonian and Laird method, a generic inverse-variance strategy. Results: Twenty studies with a total of 183,410,651 patients were included. The proportion of males was 23.7%. The median age and follow-up time were 42.4 years old (IQR: 37.4, 50.0) and 6.2 years (IQR: 1.7, 27.7), respectively. The prevalence of cannabis use was 1.9%. Cannabis use was not significantly associated with acute MI (pooled odds ratio (OR): 1.29; 95%CI: 0.80, 2.08), stroke (pooled OR 1.35; 95%CI: 0.74, 2.47), and adverse CV events (pooled OR: 1.47; 95%CI: 0.98, 2.20). Conclusion: The risk of adverse CV events including acute MI and stroke does not exhibit a significant increase with cannabis exposure. However, caution should be exercised when interpreting the findings due to the heterogeneity of the studies

Structurally Abnormal Myocardium Underlies Ventricular Fibrillation Storms in a Patient Diagnosed With the Early Repolarization Pattern

Objectives: The aim of this study was to investigate the mechanism underlying QRS-slurring in a patient with the early repolarization pattern in the electrocardiogram (ECG) and ventricular fibrillation (VF) storms. Background: The early repolarization pattern refers to abnormal ending of the QRS complex in subjects with structurally normal hearts and has been associated with VF. Methods: We studied a patient with slurring of the QRS complex in leads II, III, and aVF of the ECG and recurrent episodes of VF. Echocardiographic and imaging studies did not reveal any abnormalities. Endocardial mapping was normal but subxyphoidal epicardial access was not possible. Open chest epicardial mapping was performed. Results: Mapping showed that the inferior right ventricular free wall activated the latest with local J-waves in unipolar electrograms. The last moment of epicardial activation concurred with QRS-slurring in the ECG whereas the J-waves in the local unipolar electrograms occurred in the ST-segment of the ECG. Myocardial biopsies obtained from the late activated tissue showed severe fibrofatty alterations in the inferior right ventricular wall where fractionation and local J-waves were present. After ablation, the early repolarization pattern in the ECG disappeared and arrhythmias have been absent since (follow-up 18 months). Conclusions: In this patient, the electrocardiographic early repolarization pattern was caused by late activation due to structurally abnormal myocardium. The late activated areas were marked by J-waves in local electrograms. Ablation of these regions prevented arrhythmia recurrence and normalized the ECG

Common and rare susceptibility genetic variants predisposing to Brugada syndrome in Thailand

BACKGROUND: Mutations in SCN5A are rarely found in Thai patients with Brugada syndrome (BrS). Recent evidence suggested that common genetic variations may underlie BrS in a complex inheritance model. OBJECTIVE: The purpose of this study was to find common and rare/low-frequency genetic variants predisposing to BrS in persons in Thailand. METHODS: We conducted a genome-wide association study (GWAS) to explore the association of common variants in 154 Thai BrS cases and 432 controls. We sequenced SCN5A in 131 cases and 205 controls. Variants were classified according to current guidelines, and case-control association testing was performed for rare and low-frequency variants. RESULTS: Two loci were significantly associated with BrS. The first was near SCN5A/SCN10A (lead marker rs10428132; odds ratio [OR] 2.4; P = 3 × 10-10). Conditional analysis identified a novel independent signal in the same locus (rs6767797; OR 2.3; P = 2.7 × 10-10). The second locus was near HEY2 (lead marker rs3734634; OR 2.5; P = 7 × 10-9). Rare (minor allele frequency [MAF] 0.0001) variants also was observed in cases, with 1 variant (SCN5A: p.Arg965Cys) detected in 4.6% of Thai BrS patients vs 0.5% in controls (P = 0.015; OR 9.8; 95% CI 1.2-82.3). CONCLUSION: The genetic basis of BrS in Thailand includes a wide spectrum of variant frequencies and effect sizes. As previously shown in European and Japanese populations, common variants near SCN5A and HEY2 are associated with BrS in the Thai population, confirming the transethnic transferability of these 2 major BrS loci