Project description:Minimally-invasive treatments of cardiac arrhythmias such as radio-frequency ablation are gradually gaining importance in clinical practice but still lack a noninvasive imaging modality which provides insight into the source or focus of an arrhythmia. Cardiac deformations imaged at high temporal and spatial resolution can be used to elucidate the electrical activation sequence in normal and paced human subjects non-invasively and could potentially aid to better plan and monitor ablation-based arrhythmia treatments. In this study, a novel ultrasound-based method is presented that can be used to quantitatively characterize focal and reentrant arrhythmias. Spatio-temporal maps of the full-view of the atrial and ventricular mechanics were obtained in a single heartbeat, revealing with otherwise unobtainable detail the electromechanical patterns of atrial flutter, fibrillation, and tachycardia in humans. During focal arrhythmias such as premature ventricular complex and focal atrial tachycardia, the previously developed electromechanical wave imaging methodology is hereby shown capable of identifying the location of the focal zone and the subsequent propagation of cardiac activation. During reentrant arrhythmias such as atrial flutter and fibrillation, Fourier analysis of the strains revealed highly correlated mechanical and electrical cycle lengths and propagation patterns. High frame rate ultrasound imaging of the heart can be used non-invasively and in real time, to characterize the lesser-known mechanical aspects of atrial and ventricular arrhythmias, also potentially assisting treatment planning for intraoperative and longitudinal monitoring of arrhythmias.
Project description:Injury to structures adjacent to the heart, particularly oesophageal injury, accounts for a large proportion of fatal and life-altering complications of ablation for persistent AF. Avoiding these complications dictates many aspects of the way ablation is performed. Because avoidance involves limiting energy delivery in areas of interest, fear of extracardiac injury can impede the ability of the operator to perform an effective procedure. New techniques are becoming available that may permit the operator to circumvent this dilemma and deliver effective ablation with less risk to adjacent structures. The authors review all methods available to avoid injury to extracardiac structures to put these developments in context.
Project description:Atrial fibrillation/flutter (AF) and COVID-19 are associated with an elevated risk of arterial and venous thrombosis. Whether preadmission oral anticoagulation (OAC) for AF reduces the incidence of in-hospital death or thrombotic events among patients with COVID-19 is unknown. We identified 630 patients with pre-existing AF and a hospitalization diagnosis of COVID-19 and stratified them according to preadmission OAC use. Multivariable logistic regression was employed to relate preadmission OAC to composite in-hospital mortality or thrombotic events. Unadjusted composite in-hospital mortality or thrombotic complications occurred less often in those on than not on preadmission OAC (27.1% vs 46.8%, p <0.001). After adjustment, the incidence of composite in-hospital all-cause mortality or thrombotic complications remained lower with preadmission OAC (odds ratio 0.37, confidence interval 0.25 to 0.53, p <0.0001). Secondary outcomes including all-cause mortality (16.3% vs 24.9%, p = 0.007), intensive care unit admission (14.7% vs 29.0%, p <0.001), intubation (6.4% vs 18.6%, p <0.001), and noninvasive ventilation (18.6% vs 27.5%, p = 0.007) occurred less frequently, and length of stay was shorter (6 vs 7 days, p <0.001) in patients on than those not on preadmission OAC. A higher CHA2DS2-VASc score was associated with an increased risk of thrombotic events. In conclusion, among patients with baseline AF who were hospitalized with COVID-19, those on preadmission OAC had lower rates of death, arterial and venous thrombotic events, and less severe COVID-19.
Project description:AimsAtrial fibrillation (AF) and atrial flutter (AFL) are two of the most common atrial arrhythmias and often coexist. Many patients with AF or AFL are symptomatic, which impacts their quality of life (QoL). The purpose of this study was to determine whether coexistent AFL represents an added burden for AF patients.MethodsWe combined baseline data from two large prospective, observational, multicenter cohort studies (BEAT-AF and Swiss-AF). All 3931 patients included in this analysis had documented AF. We obtained information on comorbidities, medication, and lifestyle factors. All participants had a clinical examination and a resting ECG. Symptom burden and QoL at the baseline examination were compared between patients with and without coexistent AFL using multivariable adjusted regression models.ResultsOverall, 809 (20.6%) patients had a history of AFL. Patients with coexistent AFL more often had history of heart failure (28% vs 23%, p = 0.01), coronary artery disease (30% vs 26%, p = 0.007), failed therapy with antiarrhythmic drugs (44% vs 29%, p < 0.001), and more often underwent AF-related interventions (36% vs 17%, p < 0.001). They were more often symptomatic (70% vs 66%, p = 0.04) and effort intolerant (OR: 1.14; 95% CI: 1.01-1.28; p = 0.04). Documented AFL on the baseline ECG was associated with more symptoms (OR: 2.30; 95% CI: 1.26-4.20; p = 0.007).ConclusionOur data indicates that patients with coexistent AF and AFL are more often symptomatic and report poorer quality of life compared to patients suffering from AF only.
Project description:Left atrial appendage (LAA) thrombus detachment resulting in intracranial embolism is a major complication of atrial fibrillation (AF). Endocardial endothelial cell (EEC) injury leads to thrombosis, whereas autophagy protects against EEC dysfunction. However, the role and underlying mechanisms of autophagy in EECs during AF have not been elucidated. In this study, we isolated EECs from AF model mice and observed reduced autophagic flux and intracellular calcium concentrations in EECs from AF mice. In addition, we detected an increased expression of the mechanosensitive protein PLXND1 in the cytomembranes of EECs. PLXND1 served as a scaffold protein to bind with ORAI1 and further decreased ORAI1-mediated calcium influx. The decrease in the calcium influx-mediated phosphorylation of CAMK2 is associated with the inhibition of autophagy, which results in EEC dysfunction in AF. Our study demonstrated that the change in PLXND1 expression contributes to intracellular calcium dyshomeostasis, which inhibits autophagy flux and results in EEC dysfunction in AF. This study provides a potential intervention target for EEC dysfunction to prevent and treat intracardiac thrombosis in AF and its complications.
Project description:Abstract This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the efficacy and safety of pharmacological and electrical cardioversion for atrial fibrillation (AF).
Project description:BackgroundAtrial fibrillation (AF) is a common cardiovascular complication affecting patients with cancer, but management strategies are not well established.ObjectivesThe purpose of this retrospective cohort study was to evaluate cross-sectional patterns of anticoagulation (AC) use in patients with cancer with AF or atrial flutter (AFL) on the basis of their risk for stroke and bleeding.MethodsPatients with cancer and electrocardiograms showing AF or AFL performed at Moffitt Cancer Center in either the inpatient or outpatient setting were included in this retrospective analysis. We described percentages of AC prescription by stroke and bleeding risk, as determined by individual CHA2DS2-VASc and HAS-BLED scores, respectively. Multivariable logistic regression evaluated clinical variables independently associated with anticoagulant prescription.ResultsThe prevalence of electrocardiography-documented AF or AFL was 4.8% (n = 472). The mean CHA2DS2-VASc score was 2.8 ± 1.4. Among patients with CHA2DS2-VASc scores ≥2 and HAS-BLED scores <3, 44.3% did not receive AC, and of these, only 18.3% had platelet values <50,000/μl. In multivariable analysis, older age, hypertension, prior stroke, and history of venous thromboembolism were each directly associated with AC use, while current chemotherapy use, prior bleeding, renal disease, and thrombocytopenia were each inversely associated with AC use.ConclusionsNearly one-half of patients with cancer, the majority with normal platelet counts, had an elevated risk for stroke but did not receive AC. In addition to known predictors, current chemotherapy use was independently associated with a lower odds of AC use. This study highlights the need to improve the application of AF treatment algorithms to cancer populations.
Project description:BackgroundAtrial fibrillation (AF) is the most common sustained arrhythmia affecting over 700,000 individuals in Japan and 2.2 million in the USA. The proper management of patients with AF is critical due to the well-documented association with heart failure and stroke. A strategy to better define the emergency department (ED) management, admission decisions, and spectrum of risk from low to high is needed.Methods and subjectsThe atrial fibrillation and flutter outcomes and risk determination investigation is a prospective, observational cohort study to develop a multivariable clinical prediction rule that accurately estimates risk for adverse outcomes in patients presenting to the ED with symptomatic AF. We will enroll 430 patients at 2 sites who present to the ED with symptomatic AF defined as a new or established diagnosis of AF or atrial flutter that require ED evaluation for a complaint thought related to their rhythm disturbance. The study's endpoint is to develop an accurate, objective, internally validated, reliable clinical prediction rule to risk-stratify ED patients presenting with AF exacerbations. The rule will incorporate patient history and examination findings and laboratory studies obtained upon ED presentation, as well as trends over the first 2 h of care. This investigation's primary outcome is the incidence of any AF-related adverse event at 5 days and 30 days. We expect to complete the study by the end of 2014. The study was registered at Clinicaltrials.gov NCT01138644.
Project description:BackgroundCatheter ablation is recommended for the treatment of symptomatic atrial fibrillation (AF) refractory to medical therapy.ObjectiveThe study sought to examine racial/ethnic and sex differences in complications and AF/atrial flutter (AFL)-related acute healthcare utilization following catheter ablation for AF.MethodsWe performed a retrospective analysis using data from the Centers for Medicare and Medicaid Services Medicare Standard Analytical Files (October 1, 2014, to September 30, 2019) among patients ≥65 years of age with AF who underwent catheter ablation for rhythm control. The risk of any complication within 30 days and AF/AFL-related acute healthcare utilization within 1 year of ablation by race, ethnicity, and sex were assessed using multivariable Cox regression modeling.ResultsWe identified 95,394 patients for analysis of postablation complications and 68,408 patients for analysis of AF/AFL-related acute healthcare utilization. Both cohorts were ∼95% White and 52% male. Female patients had a slightly elevated risk of complications compared with male patients (adjusted hazard ratio [aHR] 1.07, 95% confidence interval [CI] 1.03-1.12). Black (aHR 0.78, 95% CI 0.77-1.00) and Asian (aHR 0.67, 95% CI 0.50-0.89) patients had lower utilization compared with White patients. Specifically, Asian men (aHR 0.58, 95% CI 0.38-0.91) had lower utilization compared with White men.ConclusionDifferences in safety and healthcare utilization after catheter ablation for AF were observed by race/ethnicity and sex groups. Underrepresented racial and ethnic groups with AF had a lower risk of AF/AFL-related acute healthcare utilization postablation.