left bundle branch block

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Related to Left bundle-branch block: LBBB

left bundle branch block

Cardiology A condition in which ventricular contraction is not completely synchronized due to a block in conduction of an electrical impulse to the ventricles; in LBBB, right ventricular endocardial activation begins before, and is often completed before, initiation of left ventricular endocardial activation; benign LBBB is rare; preexisting LBBB in absence of clinical evidence of heart disease is rare; newly acquired LBBB has a 10-fold ↑ in mortality Clinical Generally asymptomatic, or absent or diminished 1st heart sound–HS and reversed splitting of 2nd HS EKG Lead V1–QS or rS; lead V6–late intrinsicoid deflection, monophasic R; lead I–monophasic R Management Pacemaker, if syncope or significant arrhythmias Followup Telemetry PRN. See Bundle branch block. Cf Right bundle branch block.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

left bundle branch block

Abbreviation: LBBB
A defect in the conduction system of the heart in which electrical conduction down the left bundle branch is delayed. On the 12-lead EKG, it gives the QRS complex a widened QS complex in lead V1 (0.12 sec.).
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References in periodicals archive ?
Effects of left bundle-branch block on cardiac structure, function, perfusion, and perfusion reserve: implications for myocardial contrast echocardiography versus radionuclide perfusion imaging for the detection of coronary artery disease.
Fresco et al., "Cumulative effect of complete left bundle-branch block and chronic atrial fibrillation on 1-year mortality and hospitalization in patients with congestive heart failure: a report from the Italian network on congestive heart failure (in-CHF database)," European Heart Journal, vol.
In our post-treatment follow-up, chronic Chagas disease is indicated in three patients on the basis of these ECG findings: left anterior fascicular block, atrioventricular dissociation and intermittent left bundle-branch block, and right bundle-branch block and left posterior fascicular block, despite there being no clinical manifestation of these conditions.
A 12-lead electrocardiograph (Figure 1) showed atrial fibrillation with ventricular pacemaker spikes associated with right bundle-branch block, rather than the typical pattern of left bundle-branch block. A subsequent chest X-ray displayed the atrial lead in proper position and the ventricular lead well within the left ventricular silhouette (Figure 2).
(3-5) However, intermediate pretest probability patients with baseline ECG abnormalities such as electronically paced ventricular rhythm or left bundle-branch block will require myocardial perfusion imaging.
The American College of Cardiology and the American Heart Association revised their guidelines in 1999, elevating early mechanical intervention for cardiogenic shock to a class I recommendation for patients younger than 75 with an ST-elevation left bundle-branch block acute MI.
Three Risk Factors Predict Mortality in 15,078 Acute MI Patients Number of Risk Factors [*] 0 1 2 3 Percentage of Patients 46 41 11 2 Percent Mortality Within 30 Days 3 6 19 32 (*.) Risk factors are age 75 or older, Killip class II-IV, and ECG findings indicative of an anterior MI and/or left bundle-branch block. Source: Dr.
The major ECG abnormalities and their frequency were as follows: ventricular tachycardia (3), prolonged QTc (3), 2nd or 3rd atrioventricular block (4), complete left bundle-branch block (5), acute myocardial infarction (3).
Left bundle-branch block is associated with increased 1-year sudden and total mortality rate in 5517 outpatients with congestive heart failure: A report from the Italian network on congestive heart failure.
Chang AM, Shofer FS, Tabas JA, Magid DJ, McCusker CM, Hollander JE (2009) Lack of association between left bundle-branch block and acute myocardial infarction in symptomatic ED patients.
The aim of this study was to assess electrocardiographic variables related to the ventricular repolarization process in patients during atrial-biventricular pacing (from cardiac resynchronization therapy received as an adjunct management strategy for severe congestive heart failure associated with left bundle-branch block), by using the non-invasive method of body surface potential mapping.