Search results
Results from the WOW.Com Content Network
A premature ventricular contraction (PVC) is a common event where the heartbeat is initiated by Purkinje fibers in the ventricles rather than by the sinoatrial node. PVCs may cause no symptoms or may be perceived as a "skipped beat" or felt as palpitations in the chest.
Physiologically, the normal electrical depolarization wave is delayed at the atrioventricular node to allow the atria to contract before the ventricles. However, there is no such delay in the abnormal pathway, so the electrical stimulus passes to the ventricle by this tract faster than via normal atrioventricular/ bundle of His system, and the ...
A common example would be an interpolated PVC (a type of premature ventricular contraction) during normal sinus rhythm; the PVC does not cause an atrial contraction, because the retrograde impulse from the PVC does not completely penetrate the AV node. However, this AV node stimulation can cause a delay in subsequent AV conduction by modifying ...
An ectopic beat can be further classified as either a premature ventricular contraction (PVC), or a premature atrial contraction (PAC). [1] Some patients describe this experience as a "flip" or a "jolt" in the chest, or a "heart hiccup", while others report dropped or missed beats.
A premature heart beat or extrasystole [1] is a heart rhythm disorder corresponding to a premature contraction of one of the chambers of the heart. Premature heart beats come in two different types: premature atrial contractions and premature ventricular contractions. Often they cause no symptoms but may present with fluttering in the chest or ...
An example of premature ventricular contraction is the classic athletic heart syndrome. Sustained training of athletes causes a cardiac adaptation where the resting SAN rate is lower (sometimes around 40 beats per minute). This can lead to atrioventricular block, where the signal from the SAN is impaired in its path to the ventricles. This ...
During the ventricular contraction portion of the cardiac cycle, the Purkinje fibers carry the contraction impulse from both the left and right bundle branch to the myocardium of the ventricles. [5] This causes the muscle tissue of the ventricles to contract.
Ventricular remodeling may include ventricular hypertrophy, ventricular dilation, cardiomegaly, and other changes. It is an aspect of cardiomyopathy , of which there are many types. Concentric hypertrophy is due to pressure overload , while eccentric hypertrophy is due to volume overload .