Sinus _'s general knowledge of mechanism of cause of disease that accelerates aroused in interest

Sinus _'s general knowledge of mechanism of cause of disease that accelerates aroused in interest
The emergence of sinus tachycardia mainly relates to the fact that the excitement of sympathetic nerve and tension of nervus vagus are lowered, excited for sympathetic nerve while influencing the sinus room to form fighting cells, 4 phases rise and accelerate, reach the time of threshold potential to shorten, the heart rate is accelerated. Can cause sinus tachycardia after anaemia, generating heat, infecting, oxygen deficiency, autonomic nerve function disorder, openheart surgery. The body temperature raises 1 each time, the heart rate can increase by 12- 15 times every minute. In addition, are employing and drafting the sympathetic medicine, for instance Epinephrine, ephedrine,etc. cause the excitement of sympathetic nerve, or block medicines (such as atropine) with the nervus vagus ,Having removed the inhibition of the heart of nervus vagus, passing sinus tachycardia can happen too.

P cells in the sinus room is formed are slow response cells, except that extremely slow, the range is low, excited to conduct it slowly. Get up and fight the frequency and conduct the performance difference among every group of P cell under the normal situation. This kind of sinus room forms the difference existing functionally between the cell group, can lead to the fact that the different answering one happen between the cell group, make the sinus room form and form several and conduct the route functionally, and help to return and take shape. In addition, still there is one to lie between the sinus room to form physiologically around to form in the sinus room (slow response) With the skin of atrium (react soon) During area namely Dou room last week district. Form the intersection of knot and week of district for less than week fiber have one pair of routes that functionality separate longitudinally, conductivity and answer first inequality nature of one, can become the emergence place returned, form the pathologic foundation that is returned. Under the intersection of pathological change and terms, sinus room form and form the intersection of district and cell to answer week issues of the intersection of size and difference increase, the excited conducting the speed in these cells will be slowed down notably too. In early days in the cardiac cycle, these situations can be more obvious.
So in right time room shrink, enter the intersection of sinus and room form, in front of the issue, excited to reach the intersection of sinus and room, form blocking districting original slowly, if district this and excited over atrium break away from, answer one originally at this moment, it causes the sinus return waves echo, circulate and return and form returning tachycardia of sinus room promptly repeatedly that can be excited again. Clinical manifestation and the intersection of heart and procedure stimulate can characteristic of bringing out and stopping etc. indicate the tachycardia stopped suddenly to come down with the mechanism take place in order to return repeatedly. Also can be seen not having the organic heart disease patient.
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