Block Pattern (block + pattern)

Distribution by Scientific Domains
Medical Sciences100%

Kinds of Block Pattern

  • branch block pattern
    		•
  • bundle branch block pattern
    		•

    Selected Abstracts

    Echocardiographic Features of Patients With Heart Failure Who May Benefit From Biventricular Pacing

    ECHOCARDIOGRAPHY, Issue 3 2003
    Amgad N. Makaryus
    Background: Recent studies suggest that cardiac resynchronization therapy through biventricular pacing (BVP) may be a promising new treatment for patients with advanced congestive heart failure (CHF). This method involves implantation of pacer leads into the right atrium (RA), right ventricle (RV), and coronary sinus (CS) in patients with ventricular dyssynchrony as evidenced by a bundle branch block pattern on electrocardiogram (ECG). Clinical trials are enrolling stable patients with ejection fractions (EF) , 35%, left ventricular end-diastolic diameters (LVIDd) , 54 mm, and QRS duration ,140 msec. We compared echocardiography features of these patients (group 1) with other patients with EF , 35%, LVIDd , 54 mm, and QRS < 140 msec (group 2 = presumably no dyssynchrony). Methods: Nine hundred fifty-one patients with CHF, LVID 54 mm, EF 35% by echocardiography were retrospectively evaluated. One hundred forty-five patients remained after those with primary valvular disease, prior pacing systems, or chronic atrial arrhythmias were excluded. From this group of 145 patients, a subset of 50 randomly selected patients were further studied (25 patients [7 females, 18 males] from group 1, and 25 patients [7 females, 18 males] from group 2). Mean age group 1 = 75 years old, mean age group 2 = 67 years old. Mean QRS group 1 = 161 msec, mean QRS group 2 = 110 msec. Each group was compared for presence of paradoxical septal motion, atrial and ventricular chamber sizes, LV mass, LVEF, and RV systolic function. Results: Of the initial group of 951 patients, 145 (15%) met inclusion criteria. In the substudy, 20/25 (80%) of group l and 7/25 (28%) of group 2 subjects had paradoxical septal motion on echo (Fisher's exact test, P = 0.0005). The t-tests performed on the other echocardiography variables demonstrated no differences in chamber size, function, or LV mass. Conclusions: Cardiac resynchronization therapy with BVP appears to target a relatively small population of our advanced CHF patients (15% or less). Although increasing QRS duration on ECG is associated with more frequent paradoxical septal motion on echo, it is not entirely predictive. Paradoxical septal motion on echo may therefore be more sensitive at identifying patients who respond to BVP. Further prospective studies are needed. (ECHOCARDIOGRAPHY, Volume 20, April 2003) [source]

    Successful Radiofrequency Catheter Ablation of Epicardial Left Ventricular Outflow Tract Tachycardia from the Anterior Interventricular Coronary Vein

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2005
    YASUHIRO HIRASAWA M.D.
    We report a case of idiopathic left ventricular outflow tract (LVOT) tachycardia that was eliminated by a radiofrequency application from the anterior interventricular coronary vein (AIV). The ECG exhibited QRS complexes with an inferior axis and atypical left bundle branch block pattern with an early transition of the precordial R waves at V3. Several radiofrequency applications from the coronary cusps and endocardial LVOT were not effective. Radiofrequency applications in the AIV, where the activation preceded the onset of the QRS by 30 msec, successfully eliminated the tachycardia. The AIV may be an optional site for radiofrequency ablation of idiopathic epicardial LVOT tachycardia. [source]

    Radiofrequency Catheter Ablation of Postinfarction Ventricular Tachycardia from the Proximal Coronary Sinus

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2001
    JOSEF KAUTZNER M.D., Ph.D.
    VT Ablation from the Coronary Sinus. Optimum strategy for radiofrequency (RF) catheter ablation of ventricular tachycardia (VT) after inferior wall myocardial infarction (MI) that originates from the posteroseptal process of the left ventricle is not known. We describe a case report of a 57,year-old man who developed recurrent post-MI VT with ECG morphology consistent with this type of VT (i.e., left bundle branch block pattern with predominant R waves from V2 to V6 and left-axis deviation). Endocardial mapping and entrainment during VT demonstrated a critical isthmus of the reentrant circuit in the proximal coronary sinus. RF application terminated VT and rendered it noninducible. [source]

    Radiofrequency Catheter Ablation of an Incessant Ventricular Tachycardia Following Valve Surgery

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2002
    THORSTEN LEWALTER
    LEWALTER, T., et al.: Radiofrequency Catheter Ablation of an Incessant Ventricular Tachycardia Following Valve Surgery. Sustained monomorphic ventricular tachycardia (VT) after valve surgery represents a clinical entity with different tachycardia mechanisms. This case report describes an incessant VT after tricuspid and aortic valve replacement that did not respond to antiarrhythmic drug treatment. The tachycardia exhibited VA block and a right bundle branch block pattern with left-axis deviation, suggesting ventricular excitation via the left posterior fascicle. The electrophysiological study was limited by the prosthetic tricuspid and aortic valve replacement, therefore a transseptal approach was necessary to obtain access to the ventricular myocardium. Radiofrequency catheter ablation was performed in the proximal left bundle or distal His region with termination of the incessant VT followed by complete AV block. After pacemaker implantation using a transvenous right atrial and an epicardial ventricular lead, no VT reoccurrence could be documented. [source]

    Brugada Syndrome: Current Clinical Aspects and Risk Stratification

    ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2002
    Ph.D., Takanori Ikeda M.D.
    Brugada syndrome is a primary electrical disease of the heart that causes sudden cardiac death or life-threatening ventricular arrhythmias, especially in younger men. Genetic analysis supports that this syndrome is a cardiac ion channel disease. A typical electrocardiographic finding consists of a right bundle branch block pattern and ST-segment elevation in the right precordial leads. The higher intercostal space V1 to V3 lead electrocardiogram could be helpful in detecting Brugada patients. Although two types of the ST-segment elevation are present, the coved type is more relevant to the syndrome than the saddle-back type. These patterns can be present permanently or intermittently. Recent data suggest that the Brugada-type electrocardiogram is more prevalent than the manifest Brugada syndrome. Asymptomatic individuals have a much lower incidence of future cardiac events than the symptomatic patients. Although risk stratification for the Brugada syndrome is still incomplete, the inducibility of sustained ventricular arrhythmias has been proposed as a good outcome predictor in this syndrome. In noninvasive techniques, some clinical evidence supports that late potentials detected by signal-averaged electrocardiography are a useful index for identifying patients at risk. The available data recommend prophylactic implantation of an imptantabie cardioverter defibrillator to prevent sudden cardiac death. This review summarizes recent information of the syndrome by reviewing most of new clinical reports and speculates on its risk stratification. A.N.E. 2002;7(3):251,262 [source]

    A Case of Brugada Syndrome Presenting With Incessant Polymorphic Ventricular Tachycardia

    CLINICAL CARDIOLOGY, Issue 3 2010
    Harn-Cherng Shiue MD
    Brugada syndrome, an inherited arrhythmogenic cardiac disease, manifests with ST-segment changes in the right precordial leads, right bundle block pattern, and susceptibility to ventricular tachyarrhythmias and sudden death. The only established therapy for this disease is prevention of sudden death by implantation of a defibrillator. Herein we describe a case of a patient who presented with incessant ventricular tachycardia (VT) and syncope and who had a type 1 Brugada pattern on ECG. The patient was successfully treated with quinidine, after which the classically described type 2 and 3 patterns emerged. Copyright © 2009 Wiley Periodicals, Inc. [source]