760 research outputs found
Internship in arrhythmology
The arrhythmology focuses on the diagnosis and treatment of heart rhythm disorders and
their complications, and has undergone a dramatic evolution over the past two decades.
The widespread use of catheter ablation, the introduction of implantable cardioverter
defibrillators for the prevention of sudden cardiac death and, finally, the development of
cardiac resynchronization therapy led to a gradual loss of the impact of antiarrhythmic
drugs as a therapeutic approach.
This report was performed as a result of an internship performed in Cardiac Physiology
with the duration of 400 hours. The main goal of the internship was to strengthen
theoretical knowledge and acquire practical experience in the varied fields of
arrhythmology, especially in the areas of Cardiac Pacing and Electrophysiology.
During the internship were performed 41 electrophysiologic studies, where Atrioventricular
Node Reentrant Tachycardia and Atrial Fibrillation were the most observed arrhythmias.
New technologies such as three-dimensional mapping for electrophysiology studies are
developing quickly and being use on a daily basis, as they prove to have safe and higher
success rates. The proof is that in approximately half of the studies, one of the two
mapping systems available, Carto or NavX, was used. In addition, were interrogated 283
pacemakers during the pacing clinics, being the dual chamber with DDD pacing mode the
most encountered device. A large number of devices with Cardiac Resynchronization
Therapy and/or Implantable Cardioverter Defibrillators were also observed.
This report is divided into three chapters. Chapter I is constituted by a revision of the
literature and includes concepts such as definition and mechanisms of cardiac arrhythmias;
a brief description of the varied diagnostic tools and its recommendations; and a
presentation of the different therapeutic approaches available and its indications. The
second chapter is a descriptive drawing of the activity performed in the modules of
Electrophysiology and Pacing. Lastly, the chapter III presents two clinical cases in
Electrophysiology considered interesting from a clinical point of view
Current Issues and Recent Advances in Pacemaker Therapy
Patients with implanted pacemakers or defibrillators are frequently encountered in various healthcare settings. As these devices may be responsible for, or contribute to a variety of clinically significant issues, familiarity with their function and potential complications facilitates patient management. This book reviews several clinically relevant issues and recent advances of pacemaker therapy: implantation, device follow-up and management of complications. Innovations and research on the frontiers of this technology are also discussed as they may have wider utilization in the future. The book should provide useful information for clinicians involved in the management of patients with implanted antiarrhythmia devices and researchers working in the field of cardiac implants
A study of defibrillator waveforms, vectors, and therapies Kevin Anthony Michael.
Includes abstract.Includes bibliographical references.The defibrillation studies were performed in a porcine model given its resemblance to the human heart and its resilience to repeated ventricular fibrillation inductions (VF) and defibrillations. A novel sequential preshock waveform was assessed in a prototype serial capacitance device. Single and multi-electrode defibrillation vectors were evaluated in intra-cardiac, subcutaneous (SQ), and intra-pericardial configurations. The burden of ITS and the factors improving detection were assessed. Anti-tachycardia pacing was used to evaluate therapies in this patient cohort. The diagnostic utility of the post pacing interval (PPI) after failed ATP episodes was then investigated to help discriminate between atrial fibrillation/tachycardia (AF/AT) and VT
Arrhythmogenic Right Ventricular Cardiomyopathy: Prognostic Value of Electroanatomic Voltage Mapping
Background: Endocardial voltage mapping (EVM) identifies low-voltage right ventricular (RV) areas, which may represent the electroanatomic scar substrate of life-threatening tachyarrhythmias. We prospectively assessed the prognostic value of EVM in a consecutive series of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC).
Methods: We studied 69 consecutive ARVC patients [47 males; median age 35 years(28-45)] who underwent electrophysiological study and both bipolar and unipolar EVM. The extent of confluent bipolar (<1.5mV) and unipolar (<6.0mV) low-voltage electrograms was estimated using the CARTO-incorporated area calculation software.
Results: Fifty-three patients (77%) showed ≥1 RV electroanatomic scars with an estimated burden of bipolar vs unipolar low-voltage areas of 24.8% (7.2-31.5) and 64.8% (39.8-95.3), respectively (P=0.009). In the remaining patients with normal bipolar-EVM (n=16;23%), the use of unipolar EVM unmasked ≥1 region of low-voltage electrogram affecting 26.2% (11.6-38.2) of RV wall. During a median follow-up of 41 (28-56) months, 19(27.5%) patients experienced arrhythmic events, such as sudden death (n=1), appropriate ICD interventions (n=7), or sustained ventricular tachycardia (n=11). Univariate predictors of arrhythmic outcome included previous cardiac arrest or syncope (HR=3.4; 95%CI:1.4-8.8; P=0.03) and extent of bipolar low-voltage areas (HR=1.7 per 5%; 95%CI=1.5-2; P<0.001), while the only independent predictor was the bipolar low-voltage electrogram burden (HR=1.6 per 5%; 95% CI:1.2-1.9; P<0.001). Patients with normal bipolar-EVM had an uneventful clinical course.
Conclusions: The extent of bipolar RV endocardial low-voltage area was a powerful predictor of arrhythmic outcome in ARVC, independently of history and RV dilatation/dysfunction. A normal bipolar-EVM characterized a low-risk subgroup of ARVC patients
2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias
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