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Catheter ablation is a procedure that uses radio-frequency energy or other sources to terminate or modify a faulty electrical pathway from sections of the heart of those who are prone to developing cardiac arrhythmias such as atrial fibrillation, atrial flutter and Wolff-Parkinson-White syndrome.
Vinyl polymers are subject of several structural variations, which greatly expands the range of polymers and their applications. With the exception of polyethylene, vinyl polymers can arise from head-to-tail linking of monomers, head-to-head combined with tail-to-tail, or a mixture of those two patterns. Additionally the substituted carbon center in such polymers is stereogenic (a "chiral center")
In 101 people free of heart disease during 24 hours Holter monitoring, 39 had at least 1 PVC, and 4 at least 100. Heart disease was excluded after physical examination, chest x-ray, ECG, echocardiography, maximal exercise stress test, right- and left-heart catheterization and coronary angiography. [30]
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 ...
In the process, chlorine gas is decomposed into free radical chlorine which is then reacted with PVC in a post-production step, essentially replacing a portion of the hydrogen in the PVC with chlorine. Depending on the method, a varying amount of chlorine is introduced into the polymer allowing for a measured way to fine-tune the final properties.
Ablation near the electrode in a flashtube.The high-energy electrical arc slowly erodes the glass, leaving a frosted appearance. Ablation (Latin: ablatio – removal) is the removal or destruction of something from an object by vaporization, chipping, erosive processes, or by other means.
The aminoxyl radical (N-O•) combines with free radicals in polymers: N-O• + R• → N-O-R Although they are traditionally considered as light stabilizers, they can also stabilize thermal degradation. Even though HALS are extremely effective in polyolefins, polyethylene and polyurethane, they are ineffective in polyvinyl chloride (PVC). It ...
Depending on its formula, the PVC coating makes the material waterproof and resistant to dirt, mildew, oil, salt, chemicals and UV rays and gives the material added strength and durability. It can be sewn or heat sealed by way of RF(Radio Frequency) welding or hot-air welding.