Search results
Results from the WOW.Com Content Network
A right bundle branch block (RBBB) is a heart block in the right bundle branch of the electrical conduction system. [1] During a right bundle branch block, the right ventricle is not directly activated by impulses traveling through the right bundle branch. However, the left bundle branch still normally activates the left ventricle.
A bundle branch block can be diagnosed when the duration of the QRS complex on the ECG exceeds 120 ms. A right bundle branch block typically causes prolongation of the last part of the QRS complex and may shift the heart's electrical axis slightly to the right.
Tachycardia-dependent bundle branch block (TDBBB) can affect either ventricle in the heart, and occurs when the heart's rate of contraction reaches an elevated level and becomes uncoupled from the heart's refractory period (the time it takes for a cardiac cell to "reset" for future contraction).
When a bundle branch or their fascicles becomes injured (by underlying heart disease, myocardial infarction, or cardiac surgery), it may cease to conduct electrical impulses appropriately, resulting in altered pathways for ventricular depolarization. This condition is known as a bundle branch block. [3]
An intraventricular block is a heart conduction disorder — heart block of the ventricles of the heart. [1] An example is a right bundle branch block, right fascicular block, bifascicular block, trifascicular block. [2] [3]
A bundle branch block either LBBB or RBBB, (although RBBB is known to be associated only with S1 split), will produce continuous splitting but the degree of splitting will still vary with respiration. When the pulmonary valve closes before the aortic valve, this is known as a "paradoxically split S 2 ". [6]
JET in a 2-month-old girl following cardiac surgery. In this case the right bundle branch block was present during tachycardia and during normal sinus rhythm. JET is most commonly diagnosed using a 12-lead ECG. The appearance is usually of a tachycardia with rapid, regular ventricular rates of 170-260 beats per minute. [6]
The ostium primum atrial septal defect is a defect in the atrial septum at the level of the tricuspid and mitral valves. This is sometimes known as an endocardial cushion defect because it often involves the endocardial cushion, which is the portion of the heart where the atrial septum meets the ventricular septum and the mitral valve meets the tricuspid valve.