Impact of Achieving Blood Pressure Targets and High Time in Therapeutic Range on Clinical Outcomes in Patients With Atrial Fibrillation Adherent to the Atrial Fibrillation Better Care Pathway: A Report From the COOL-AF Registry.

Background We aimed to determine the effect of integrating Atrial Fibrillation Better Care pathway compliance in relation to achievement of systolic blood pressure (SBP) targets and good control of time in therapeutic range (TTR) on clinical outcomes in patients with atrial fibrillation. Methods and Results We prospectively enrolled patients with nonvalvular atrial fibrillation  from 27 hospitals in Thailand. All clinical outcomes were recorded. Main outcomes were the composite of all-cause death or ischemic stroke/systemic embolism (SSE), as well as secondary outcomes of all-cause death, SSE, major bleeding, intracranial hemorrhage, and heart failure. An SBP of 120 to 140 mm Hg was considered good blood pressure control. Target TTR was a TTR ≥65%. A total of 3405 patients were studied (mean age 67.8 years, 41.8% female). Full ABC pathway compliance was evident in 42.7%. For blood pressure control, 41.9% had SBP within target, whereas 35.9% of those on warfarin had TTR within target. The incidence rates of all-cause death/SSE, all-cause death, SSE, major bleeding, intracranial hemorrhage, and heart failure were 5.29, 4.21, 1.51, 2.25, 0.78, and 2.84 per 100 person-years respectively. Adjusted hazard ratios and 95% CI of Atrial Fibrillation Better Care pathway compliance for all-cause death/SSE, all-cause death, and heart failure were 0.76 (0.62-0.94), 0.79 (0.62-0.99), and 0.69 (0.51-0.94), respectively, compared with noncompliance. Patients with Atrial Fibrillation Better Care compliance and SBP within target had a better outcome or TTR within target had better outcomes. Conclusions In COOL-AF (Cohort of Antithrombotic Use and Optimal International Normalized Ratio Level in Patients With Non-Valvular Atrial Fibrillation in Thailand), a multicenter nationwide prospective cohort of patients with atrial fibrillation, achieving SBP within target and TTR ≥ 65% has added value to Atrial Fibrillation Better Care pathway compliance in the reduction of adverse clinical outcomes in patients with atrial fibrillation.

Outcome disparities in patients with atrial fibrillation based on insurance plan and educational attainment: a nationwide, multicenter and prospective cohort trial.

BACKGROUND: Atrial fibrillation (AF) is a complex disease. The management of AF requires continuous patient engagement and integrative healthcare. OBJECTIVES: To explore the association between adverse AF-related clinical outcomes and the following two sociodemographic factors: educational attainment and insurance plan. DESIGN: A nationwide, prospective, multicenter, cohort trial. SETTING: National registry of 3402 patients with non-valvular AF in Thailand. PARTICIPANTS: All patients enrolled in the registry, except those with missing information on educational attainment or insurance plan. Finally, data from 3026 patients (mean age 67 years, SD 11.3; 59% male sex) were analysed. PRIMARY OUTCOMES: Incidences of all-cause mortality, ischaemic stroke and major bleeding during the 36-month follow-up period. Survival analysis was performed using restricted mean survival time (RMST) and adjusted for multiple covariates. The levels of the educational attainment were as follows: no formal education, elementary (grade 1-6), secondary (grade 7-12) and higher education (tertiary education). RESULTS: The educational attainment of the majority of patients was elementary (N=1739, 57.4%). The predominant health insurance plans were the Civil Servant Medical Benefit Scheme (N=1397, 46.2%) and the Universal Coverage Scheme (N=1333, 44.1%). After 36 months of follow-up, 248 patients died (8.2%), 95 had ischaemic stroke (3.1%) and 136 had major bleeding (4.5%). Patients without formal education died 1.78 months earlier (adjusted RMST difference -1.78; 95% CI, -3.25 to -0.30; p=0.02) and developed ischaemic stroke 1.04 months sooner (adjusted RMST difference -1.04; 95% CI, -2.03 to -0.04; p=0.04) than those attained a level of higher education. There were no significant differences in RMSTs for all three clinical outcomes when considering the type of health insurance plan. CONCLUSION: Educational attainment was independently associated with all-cause mortality and ischaemic stroke in patients with AF, but adverse clinical outcomes were not related to the types of health insurance in Thailand. TRIAL REGISTRATION NUMBER: Thai Clinical Trial Registration; Study ID: TCTR20160113002.

Prevalence and predictors of cardiac and liver iron overload in patients with thalassemia: A multicenter study based on real-world data.

Prevalence of cardiac and liver iron overload in patients with thalassemia in real-world practice may vary among different regions especially in the era of widely-used iron chelation therapy. The aim of this study was to determine the prevalence of cardiac and liver iron overload in and the management patterns of patients with thalassemia in real-world practice in Thailand. We established a multicenter registry for patients with thalassemia who underwent magnetic resonance imaging (MRI) as part of their clinical evaluation. All enrolled patients underwent cardiac and liver MRI for assessment of iron overload. There were a total of 405 patients enrolled in this study. The mean age of patients was 18.8±12.5years and 46.7% were male. Two hundred ninety-six (73.1%) of patients received regular blood transfusion. Prevalence of cardiac iron overload (CIO) and liver iron overload (LIO) was 5.2% and 56.8%, respectively. Independent predictors for iron overload from laboratory information were serum ferritin and transaminase for both CIO and LIO. Serum ferritin can be used as a screening tool to rule-out CIO and to diagnose LIO. Iron chelation therapy was given in 74.6%; 15.3% as a combination therapy.

Determining the Site of Accessory Pathways in Orthodromic Reciprocating Tachycardia by Using the Response to Right Ventricular Pacing.

BACKGROUND: Postpacing interval (PPI) after right ventricular (RV) pacing entrainment minus tachycardia cycle length (TCL) with a correction for atrioventricular (AV) node delay (corrected PPI-TCL) was useful to differentiate atrioventricular node reentrant tachycardia (AVNRT) from orthodromic reciprocating tachycardia (ORT). However, the value of corrected PPI-TCL in determining the site of the accessory pathway (AP) in ORT has not been investigated. The purpose of this study was to assess whether the corrected PPI-TCL is useful in differentiating ORT using a left-sided AP from a right-sided AP. METHODS: We studied 52 patients with ORT using a left-sided AP and 13 patients with a right-sided AP. The PPI was measured upon cessation of the RV pacing at a cycle length 10-40 ms shorter than the TCL. The corrected PPI-TCL was calculated from the subtraction of the increment in AV nodal conduction time of the first PPI from the PPI-TCL. RESULTS: The mean corrected PPI-TCL was 83 ± 20 ms in patients with ORT using a left-sided AP and 27 ± 19 ms in patients with a right-sided AP (P ≤ 0.001). All patients with ORT using a left-sided AP except three patients with left septal AP and none of the patients with ORT using a right-sided AP had a corrected PPI-TCL > 55 ms. CONCLUSIONS: The corrected PPI-TCL after the RV pacing entrainment is useful to guide differentiating ORT using a left-sided AP from a right-sided AP.

Improved R2* liver iron concentration assessment using a novel fuzzy c-mean clustering scheme.

BACKGROUND: In thalassemia patients, R2* liver iron concentration (LIC) measurement is a common clinical tool for assessing iron overload and for determining necessary chelator dose and evaluating its efficacy. Despite the importance of accurate LIC measurement, existing methods suffer from LIC variability, especially at the severe iron overload range due to inclusion of vessel parts in LIC calculation. In this study, we build upon previous Fuzzy C-Mean (FCM) clustering work to formulate a scheme with superior performance in segmenting vessel pixels from the parenchyma. Our method (MIX-FCM) combines our novel 2D-FCM with the existing 1D-FCM algorithm. This study further assessed possible optimal clustering parameters (OP scheme) and proposed a semi-automatic (SA) scheme for routine clinical application. METHODS: Segmentation of liver parenchyma and vessels was performed on T2* images and their LIC maps in 196 studies from 147 thalassemia major patients. We used manual segmentation as the reference. 1D-FCM clustering was performed on the acquired image alone and 2D-FCM used both the acquired image and its LIC data. To execute the MIX-FCM method, the best outcome (OP-MIX-FCM) was selected from the aforementioned methods and was compared to the SA-MIX-FCM scheme. We used the percent value of the normalized interquartile range (nIQR) to its median to evaluate the variability of all methods. RESULTS: 2D-FCM clustering is more effective than 1D-FCM clustering at the severe overload range only, but inferior for other ranges (where 1D-FCM provides suitable results). This complementary performance between the two methods allows MIX-FCM to improve results for all ranges. OP-MIX-FCM clustering error was 2.1 ± 2.3%, compared with 10.3 ± 9.9% and 7.0 ± 11.9% from 1D- and 2D-FCM clustering, respectively. SA-MIX-FCM result was comparable to OP-MIX-FCM result, with both schemes showing ability to decrease overall nIQR by approximately 30%. CONCLUSION: Our proposed 2D-FCM algorithm is not as superior to 1D-FCM as hypothesized. In contrast, our MIX-FCM method benefits from the best of both methods to obtain the highest segmentation accuracy at all ranges. Moreover, segmentation accuracy of the practical scheme (SA-MIX-FCM) is comparable to segmentation accuracy of the reference scheme (OP-MIX-FCM). Finally, we confirmed that segmentation is crucial to improving LIC assessments, especially at the severe iron overload range.

One-year outcome after radiofrequency catheter ablation of symptomatic ventricular arrhythmia from right ventricular outflow tract.

Although ventricular premature complexes (VPCs) in patients without structural heart disease are benign, many patients experience disabling symptoms. Many patients need long-term medication, which is often ineffective and may have adverse effects. Radiofrequency catheter ablation (RFCA) may be an alternative treatment. RFCA was performed in 33 patients with severely symptomatic VPCs that were refractory to medication. Mean VPCs were 23,987 +/- 2,077 beats/24 hours. Twenty-four-hour ambulatory electrocardiographic monitoring, quality of life, and symptoms were assessed at a screening visit and 1 and 12 months after RFCA. RFCA was successfully performed in 32 patients (97%). This resulted in a significant improvement in symptoms, severity of ventricular arrhythmia, and quality of life at 1 and 12 months after the procedure. There were no major complications related to the procedure. Eight patients (24%) had residual arrhythmia. Five of them underwent repeated ablation with successful results. Thus, catheter ablation is a safe and effective treatment for symptomatic ventricular arrhythmia from the right ventricular outflow tract. It also improves the quality of life. Catheter ablation is a viable alternative to drugs in the presence of disabling symptoms.