Ratika Parkash

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BACKGROUND Standard perfusion imaging may underestimate the extent of disease in 3-vessel coronary atherosclerosis. This study determined whether positron emission tomography quantification of perfusion reserve by use of rubidium 82 net retention defined a greater extent of disease than the standard approach in patients with 3-vessel disease. METHODS AND(More)
BACKGROUND Defibrillation threshold (DFT) testing has traditionally been a routine part of implantable cardioverter-defibrillator (ICD) implantation, despite a lack of compelling evidence that it predicts or improves outcomes. In the past, when devices were much less reliable, DFT testing seemed prudent; however, modern ICD systems have such a high rate of(More)
BACKGROUND Approximately 268,000 Fidelis leads were implanted worldwide until distribution was suspended because of a high rate of early failure. Careful analyses of predictors of increased lead failure hazard are required to help direct future lead design and also to inform decision making on lead replacement. We sought to perform a comprehensive analysis(More)
The era of gene discovery and molecular medicine has had a significant impact on clinical practice. Knowledge of specific genetic findings causative for or associated with human disease may enhance diagnostic accuracy and influence treatment decisions. In cardiovascular disease, gene discovery for inherited arrhythmia syndromes has advanced most rapidly.(More)
BACKGROUND Patients with advanced heart disease are at risk from sudden death; however, benefit from implantable cardioverter defibrillators (ICDs) may be limited as a result of early mortality from other causes. The objective of this study was to develop a model to predict mortality within the first year after ICD implantation. METHODS AND RESULTS A(More)
BACKGROUND Using data from the Resynchronization/Defibrillation for Ambulatory Heart Failure (RAFT) study, we examined whether Fidelis lead failure was more common in patients with implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (ICD-CRT) than in patients with an ICD only. METHODS AND RESULTS All cases of patients who(More)
BACKGROUND A unique form of lead failure has been described in the Riata (8-F) and Riata ST (7-F) silicone defibrillation lead degradation of the outer insulation, resulting in the externalization of conductor cables. OBJECTIVE To assess rates of lead revision due to lead failure in Riata leads affected by the Riata advisory. METHODS Nineteen(More)
BACKGROUND Atrial fibrillation (AF) is the most common adult arrhythmia, and significantly increases the risk of ischemic stroke. Oral anticoagulation may be underused and may be less effective in community settings than clinical trial settings. OBJECTIVES To determine the rates of thromboembolism and bleeding in an ambulatory cohort of patients with AF.(More)
INTRODUCTION Pulmonary vein antrum isolation (PVAI) is an accepted treatment for atrial fibrillation (AF) refractory to medical therapy. The purpose of this study was to identify the patient, procedural, and follow-up factors associated with arrhythmia recurrences following PVAI. METHODS AND RESULTS Clinical data were prospectively collected on all 385(More)
BACKGROUND Cardiac resynchronization (CRT) prolongs survival in patients with systolic heart failure and QRS prolongation. However, most trials excluded patients with permanent atrial fibrillation. METHODS AND RESULTS The Resynchronization for Ambulatory Heart Failure Trial (RAFT) randomized patients to an implantable cardioverter defibrillator (ICD) or(More)