Rationale and Design of the Personalized Therapy Study: Evaluating Real-World Performance of Two Automated Defibrillation Therapy Algorithms.

Background: Barriers to maximizing patient benefit with implantable defibrillation devices include limited ability to tailor antitachycardia pacing (ATP) therapy in real-time and identify patients at risk of heart failure (HF) events early on. The Personalized Therapy study aims to evaluate the performance of two algorithms, intrinsic ATP (iATP) and TriageHF, to address these barriers in routine clinical practice.

Methods And Results: The Personalized Therapy Study was designed as a prospective, multicenter, post-market registry study expected to enroll approximately 2,200 patients meeting the following criteria: (1) implanted with a study-eligible device regardless of procedure type; (2) Medtronic CareLink® Network enrolled; (3) TriageHF enabled within CareLink and High Risk Alert notifications turned ON; and (4) iATP enabled.

Left Atrial Appendage Ligation Using the AtriClip Device: Single-Center Study of Device Safety and Efficacy.

Left atrial appendage (LAA) occlusion at the time of cardiac surgery in patients with atrial fibrillation has been shown to reduce the incidence of postoperative embolic stroke. However, the optimal method for LAA occlusion is not universally accepted. We sought to examine the safety and effectiveness of LAA occlusion with the AtriClip epicardial occlusion device.

A heart-team hybrid approach for atrial fibrillation: a single-centre long-term clinical outcome cohort study.

Objectives: The Cox-maze IV is the gold standard for surgical ablation of atrial fibrillation (AF). A heart-team hybrid approach using selected epicardial thoracoscopic surgical ablations and completion endocardial ablations to replicate the Cox-maze IV lesion set has gained popularity and early results have been promising. We herein report our single-centre long-term clinical outcomes using the heart-team hybrid approach with 455 patients.

First-in-Human Experience of Mechanical Preload Control in Patients With HFpEF During Exercise.

Exercise intolerance remains one of the major factors determining quality of life in heart failure patients. In 6 patients with heart failure with preserved ejection fraction (HFpEF) undergoing invasive cardiopulmonary exercise testing, balloon inflation within the inferior vena cava (IVC) was performed during exercise to reduce and maintain pulmonary arterial (PA) pressures. Partial IVC occlusion significantly reduced PA pressures without reducing cardiac output.

Incidence and outcomes of patients with atrial fibrillation and major bleeding complications: from the TREAT-AF study.

Purpose: Optimal stroke prevention strategies for patients with atrial fibrillation (AF) who experience a major bleed are poorly defined. We sought to estimate the effectiveness and safety of oral anticoagulation (OAC) represcription after an OAC contraindication.

Methods: TREAT-AF is a retrospective cohort study of patients with newly diagnosed AF (2004-2012), treated in the Veterans Health Administration.

Comparison of Patient-Reported Care Satisfaction, Quality of Warfarin Therapy, and Outcomes of Atrial Fibrillation: Findings From the ORBIT - AF Registry.

Background Patient satisfaction with therapy is an important metric of care quality and has been associated with greater medication persistence. We evaluated the association of patient satisfaction with warfarin therapy to other metrics of anticoagulation care quality and clinical outcomes among patients with atrial fibrillation ( AF ). Methods and Results Using data from the ORBIT - AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) registry, patients were identified with AF who were taking warfarin and had completed an Anti-Clot Treatment Scale ( ACTS ) questionnaire, a validated metric of patient-reported burden and benefit of oral anticoagulation.

A novel pacing maneuver to verify the postpacing interval minus the tachycardia cycle length while adjusting for decremental conduction: Using "dual-chamber entrainment" for improved supraventricular tachycardia discrimination.

Background: The postpacing interval (PPI) minus the tachycardia cycle length (TCL) is frequently used to investigate tachycardias. However, a variety of issues (eg, failure to entrain, decremental conduction, and oscillating TCLs) can make interpretation of the PPI-TCL challenging.

Objective: The purpose of this study was to investigate a novel maneuver to confirm the PPI-TCL value without using either the ventricular PPI or the TCL interval and to assess the ability of this maneuver to identify decremental conduction and differentiate supraventricular tachycardias.

Patient and facility variation in costs of catheter ablation for atrial fibrillation.

Background: Cost-effectiveness or value of cardiovascular therapies may be undermined by unwarranted cost variation, particularly for heterogeneous procedures such as catheter ablation for atrial fibrillation (AF). We sought to characterize cost variation of AF ablation in the US healthcare system and the relationship between cost and outcomes.

Methods And Results: We performed a retrospective cohort study using data from the MarketScan commercial claims and Medicare supplemental databases including patients who received an AF ablation from 2007 to 2011.

Treating Specialty and Outcomes in Newly Diagnosed Atrial Fibrillation: From the TREAT-AF Study.

Background: Atrial fibrillation (AF) occurs in many clinical contexts and is diagnosed and treated by clinicians across many specialties. This approach has resulted in treatment variations.

Objectives: The goal of this study was to evaluate the association between treating specialty and AF outcomes among patients newly diagnosed with AF.

Warfarin utilisation and anticoagulation control in patients with atrial fibrillation and chronic kidney disease.

Objective: To evaluate warfarin prescription, quality of international normalised ratio (INR) monitoring and of INR control in patients with atrial fibrillation (AF) and chronic kidney disease (CKD).

Methods: We performed a retrospective cohort study of patients with newly diagnosed AF in the Veterans Administration (VA) healthcare system. We evaluated anticoagulation prescription, INR monitoring intensity and time in and outside INR therapeutic range (TTR) stratified by CKD.

Gender Differences in Clinical Outcomes after Catheter Ablation of Atrial Fibrillation.

Objective: To explore gender differences in real-world outcomes after catheter ablation of atrial fibrillation (AF).

Background: Compared to men, women with AF have greater thromboembolic risk and tend to be more symptomatic. Catheter ablation is generally more effective than antiarrhythmic drug therapy alone.

Safety and Clinical Outcomes of Catheter Ablation of Atrial Fibrillation in Patients With Chronic Kidney Disease.

Introduction: Data regarding catheter ablation of atrial fibrillation (AF) in patients with chronic kidney disease (CKD) is limited. We therefore assessed the association of CKD with common safety and clinical outcomes in a nationwide sample of ablation recipients.

Methods: Using MarketScan Commercial Claims and Medicare Supplemental Databases, we evaluated 30-day safety and 1-year clinical outcomes in patients who underwent a first AF ablation procedure between 2007 and 2011.

Transforming the care of atrial fibrillation with mobile health.

Atrial fibrillation (AF) is a multifaceted and highly variable disease that is often difficult to manage within the traditional health-care model. The conventional model of regular or pre-scheduled appointments with physicians or allied health professionals is poorly suited to the unpredictable and often urgent clinical needs of patients with AF. Mobile health (mHealth) has the potential to dramatically transform the delivery and quality of AF care.

Cost-Effectiveness of Implantable Pulmonary Artery Pressure Monitoring in Chronic Heart Failure.

Objectives: This study aimed to evaluate the cost-effectiveness of the CardioMEMS (CardioMEMS Heart Failure System, St Jude Medical Inc, Atlanta, Georgia) device in patients with chronic heart failure.

Background: The CardioMEMS device, an implantable pulmonary artery pressure monitor, was shown to reduce hospitalizations for heart failure and improve quality of life in the CHAMPION (CardioMEMS Heart Sensor Allows Monitoring of Pressure to Improve Outcomes in NYHA Class III Heart Failure Patients) trial.

Methods: We developed a Markov model to determine the hospitalization, survival, quality of life, cost, and incremental cost-effectiveness ratio of CardioMEMS implantation compared with usual care among a CHAMPION trial cohort of patients with heart failure.

The precise timing of tachycardia entrainment is determined by the postpacing interval, the tachycardia cycle length, and the pacing rate: Theoretical insights and practical applications.

Background: Previous observations have reported that the number of pacing stimuli required to entrain a tachycardia varies on the basis of arrhythmia type and location, but a quantitative formulation of the number needed to entrain (NNE) that unifies these observations has not been characterized.

Objective: We sought to investigate the relationship between the number of pacing stimulations, the tachycardia cycle length (TCL), the overdrive pacing cycle length (PCL), and the postpacing interval (PPI) to accurately estimate the timing of tachycardia entrainment.

Methods: First, we detailed a mathematical derivation unifying electrophysiological parameters with empirical confirmation in 2 patients undergoing catheter ablation of typical atrial flutter.

Amiodarone and risk of death in contemporary patients with atrial fibrillation: Findings from The Retrospective Evaluation and Assessment of Therapies in AF study.

Background: There are limited data on mortality outcomes associated with use of amiodarone in atrial fibrillation and flutter (AF).

Methods: We evaluated the association of amiodarone use with mortality in patients with newly diagnosed AF using complete data from the Department of Veterans Affairs national health care system. We included patients seen in an outpatient setting within 90 days of a new diagnosis for nonvalvular AF between Veterans Affairs fiscal years 2004 and 2008.

Defibrillator implantations for primary prevention in the United States: Inappropriate care or inadequate documentation: Insights from the National Cardiovascular Data ICD Registry.

Background: Prior studies have reported that more than 20% of implantable cardioverter-defibrillator (ICD) implantations in the United States do not adhere to trial-based criteria.

Objective: We sought to investigate the patient characteristics associated with not meeting the inclusion criteria of the clinical trials that have demonstrated the efficacy of primary prevention ICDs.

Methods: Using data from the National Cardiovascular Data Registry's ICD Registry, we identified patients who received ICDs for primary prevention from January 2006 to December 2008.

The clinical efficacy of dabigatran etexilate for preventing stroke in atrial fibrillation patients.

The use of novel oral anticoagulants (NOACs) for stroke and systemic embolism prevention in the setting of specifically non valvular atrial fibrillation has provided clinicians with a realistic treatment alternative to the traditional dose-adjusted, warfarin-based anticoagulation that is targeted to a therapeutic international normalized ratio range of 2.0-3.0.

Continuous warfarin versus periprocedural dabigatran to reduce stroke and systemic embolism in patients undergoing catheter ablation for atrial fibrillation or left atrial flutter.

Purpose: Left atrial catheter ablation for patients with atrial fibrillation (AF) requires periprocedural anticoagulation to minimize thromboembolic complications. High rates of major bleeding complications using dabigatran etexilate for periprocedural anticoagulation have been reported, raising concerns regarding its safety during left atrial catheter ablation. We sought to evaluate the safety and efficacy of a dabigatran use strategy versus warfarin, at a single high-volume AF ablation center.

Mutations in sodium channel β1- and β2-subunits associated with atrial fibrillation.

Background: We and others have reported mutations in the cardiac predominant sodium channel gene SCN5A in patients with atrial fibrillation (AF). We also have reported that SCN1B is associated with Brugada syndrome and isolated cardiac conduction disease. We tested the hypothesis that mutations in the 4 sodium channel beta-subunit genes SCN1B-SCN4B contribute to AF susceptibility.

ACE I/D polymorphism associated with abnormal atrial and atrioventricular conduction in lone atrial fibrillation and structural heart disease: implications for electrical remodeling.

Background: The angiotensin-converting enzyme (ACE) gene contains a common polymorphism based on the insertion (I) or deletion (D) of a 287-bp intronic DNA fragment. The D allele is associated with higher ACE activity and thus higher angiotensin II levels. Angiotensin II stimulates cardiac fibrosis and conduction heterogeneity.