Relationship between sodium channel function and clinical phenotype in SCN5A variants associated with Brugada syndrome.

The identification of a pathogenic SCN5A variant confers an increased risk of conduction defects and ventricular arrhythmias (VA) in Brugada syndrome (BrS). However, specific aspects of sodium channel function that influence clinical phenotype have not been defined. A systematic literature search identified SCN5A variants associated with BrS. Sodium current (INa ) functional parameters (peak current, decay, steady-state activation and inactivation, and recovery from inactivation) and clinical features (conduction abnormalities [CA], spontaneous VA or family history of sudden cardiac death [SCD], and spontaneous BrS electrocardiogram [ECG]) were extracted. A total of 561 SCN5A variants associated with BrS were identified, for which data on channel function and clinical phenotype were available in 142. In the primary analysis, no relationship was found between any aspect of channel function and CA, VA/SCD, or spontaneous BrS ECG pattern. Sensitivity analyses including only variants graded pathogenic or likely pathogenic suggested that reduction in peak current and positive shift in steady-state activation were weakly associated with CA and VA/SCD, although sensitivity and specificity remained low. The relationship between in vitro assessment of channel function and BrS clinical phenotype is weak. The assessment of channel function does not enhance risk stratification. Caution is needed when extrapolating functional testing to the likelihood of variant pathogenicity.

Invasive Management of Hypertrophic Cardiomyopathy With Clinically Important Obstruction: Catheter Intervention Is Superior.

Hypertrophic cardiomyopathy is a common inherited cardiac condition where the myocardium progressively thickens in the absence of abnormal loading conditions. Left ventricular hypertrophy often leads to outflow tract obstruction, and this confers significant mortality and morbidity implications. Septal reduction therapies aim to relieve the obstruction in an attempt to reduce the burden of symptoms and potentially improve prognosis. However, both surgical and catheter-based approaches to septal reduction carry risks. At present, international guidelines and expert consensus statements suggest surgical myomectomy is the gold-standard treatment. In this point-counterpoint review, we discuss why in our opinion this recommendation should be reconsidered. We hope to cover the history of catheter based septal reduction therapies and the significant advances made over the last two decades. We also hope to show why we believe the current evidence shows catheter-based alcohol septal ablation is superior to surgical myomectomy.

Embolization of percutaneous left atrial appendage closure devices: Timing, management and clinical outcomes.

BACKGROUND: Left atrial appendage (LAA) occluder embolization is an infrequent but serious complication. OBJECTIVES: We aim to describe timing, management and clinical outcomes of device embolization in a multi-center registry. METHODS: Patient characteristics, imaging findings and procedure and follow-up data were collected retrospectively. Device embolizations were categorized according to 1) timing 2) management and 3) clinical outcomes. RESULTS: Sixty-seven centers contributed data. Device embolization occurred in 108 patients. In 70.4 % of cases, it happened within the first 24 h of the procedure. The device was purposefully left in the LA and the aorta in two (1.9 %) patients, an initial percutaneous retrieval was attempted in 81 (75.0 %) and surgery without prior percutaneous retrieval attempt was performed in 23 (21.3 %) patients. Two patients died before a retrieval attempt could be made. In 28/81 (34.6 %) patients with an initial percutaneous retrieval attempt a second, additional attempt was performed, which was associated with a high mortality (death in patients with one attempt: 2.9 % vs. second attempt: 21.4 %, p < 0.001). The primary outcome (bailout surgery, cardiogenic shock, stroke, TIA, and/or death) occurred in 47 (43.5 %) patients. Other major complications related to device embolization occurred in 21 (19.4 %) patients. CONCLUSIONS: The majority of device embolizations after LAA closure occurs early. A percutaneous approach is often the preferred method for a first rescue attempt. Major adverse event rates, including death, are high particularly if the first retrieval attempt was unsuccessful. CONDENSED ABSTRACT: This dedicated multicenter registry examined timing, management, and clinical outcome of device embolization. Early embolization (70.4 %) was most frequent. As a first rescue attempt, percutaneous retrieval was preferred in 75.0 %, followed by surgical removal (21.3 %). In patients with a second retrieval attempt a higher mortality (death first attempt: 2.9 % vs. death second attempt: 24.1 %, p < 0.001) was observed. Mortality (10.2 %) and the major complication rate after device embolization were high.

Social determinants of health and recurrence of atrial fibrillation after catheter ablation: a Danish nationwide cohort study.

AIMS: To examine the associations between three social determinants of health (SDOH) and recurrence of AF after ablation. METHODS AND RESULTS: We selected patients who underwent a first ablation after an incident hospital diagnosis of AF between 2005 and 2018 from the entire Danish population. Educational attainment, family income, and whether the patient was living alone were assessed at the time of ablation. We used cause-specific proportional hazard models to estimate hazard ratios (HR) with 95% confidence interval (CI) adjusted for age and sex. In secondary analyses, we adjusted for comorbidities, antiarrhythmic medication, and prior electrical cardioversion.We selected 9728 patients (mean age 61 years, 70% men), and 5881 patients had AF recurrence over an average of 1.37 years after ablation (recurrence rate 325.7 (95% CI 317.6-334.2) per 1000 person-years). Lower education (HR 1.09 [1.02-1.17] and 1.07 [1.01-1.14] for lower and medium vs. higher), lower income [HR 1.14 (1.06-1.22) and 1.09 (1.03-1.17) for lower and medium vs. higher], and living alone [HR 1.07 (1.00-1.13)] were associated with increased rates of recurrence of AF. We found no evidence of interaction between sex or prior HF with SDOH. The association between family income and AF recurrence was stronger among patients < 65 years compared with those aged ≥ 65 years. The associations between SDOH and AF recurrence did not persist in the multivariable model. CONCLUSION: AF was more likely to recur among patients with lower educational attainment, lower family income, or those living alone. Multidisciplinary efforts are needed to reduce socioeconomic inequity in the effect of ablation.

Risk of Major Bleeding With Potent Antiplatelet Agents After an Acute Coronary Event: A Comparison of Ticagrelor and Clopidogrel in 5116 Consecutive Patients in Clinical Practice.

Background Major bleeding after acute coronary syndrome predicts a poor outcome but is challenging to define. The choice of antiplatelet influences bleeding risk. Methods and Results Major bleeding, subsequent myocardial infarction (MI), and all-cause mortality to 1 year were compared in consecutive patients with acute coronary syndrome treated with clopidogrel (n=2491 between 2011 and 2013) and ticagrelor (n=2625 between 2012 and 2015) in 5 English hospitals. Clinical outcomes were identified from national hospital episode statistics. Bleeding and MI events were independently adjudicated by 2 experienced clinicians, blinded to drug, sequence, and year. Bleeding events were categorized using Bleeding Academic Research Consortium 3 to 5 and PLATO (Platelet Inhibition and Patient Outcomes) criteria and MI by the Third Universal Definition. Multivariable regression analysis was used to adjust outcomes for case mix. The median age was 68 years and 34% were women. 39% underwent percutaneous coronary intervention and 13% coronary artery bypass graft surgery. Clinical outcome data were 100% complete for bleeding and 99.7% for MI. No statistically significant difference was seen in crude or adjusted major bleeding for ticagrelor compared with clopidogrel (Bleeding Academic Research Consortium 3-5, hazard ratio [HR], 1.23; 95% CI, 0.90-1.68; P=0.2, PLATO major adjusted HR, 1.30; 95% CI, 0.98-1.74; P=0.07) except in the non-coronary artery bypass graft cohort (n=4464), where bleeding was more frequent with ticagrelor (Bleeding Academic Research Consortium 3-5, adjusted HR, 1.58; 95% CI, 1.09-2.31; P=0.017; and PLATO major HR, 1.67; 95% CI, 1.18-2.37; P=0.004). There was no difference in crude or adjusted subsequent MI (adjusted HR, 1.20; 95% CI, 0.87-1.64; P=0.27). Crude mortality was higher in the clopidogrel group but not after adjustment, using either Cox proportional hazards or propensity matched population (HR, 0.90; 95% CI, 0.76-1.10; P=0.21) as was the case for stroke (HR, 0.82; 95% CI, 0.52-1.32; P=0.42). Conclusions This observational study indicates that the apparent benefit of ticagrelor demonstrated in a clinical trial population may not be observed in the broader population encountered in clinical practice. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02484924.