Artery pathologic _'s symptom of a narrow cause of disease of the lung

Artery pathologic _'s symptom of a narrow cause of disease of the lung
A narrow incidence of lung artery accounts for 8% of congenital heart disease- 10%. Several patients are plump with parts of narrow or funnel department skin bunch lung artery funnels. It is the sufficient development of three leaves that a narrow pathology of lung artery dissects the characteristic, clear in juncture of a leaf, but merge and form curtains each other, make a mouth obviously narrow. A ring of lung artery is very normal, or hypoplasia that a few patients and a ring are little. Expand after the lung artery backbone is narrow, and often extend to the artery near end of left lung. Have not often closed atrial septal defect with the oval hole.
This disease is one kind of a common congenital heart disease, it is caused by a abnormal development of embryo, too may it has lungs to continue person who send to be artery mouth narrow, cause because of other disease, if it can cause a disease to infect in foetus' palace. The pathologic physiology of this disease changes as follows:
First, cause of disease
All kinds of lung the intersection of artery and the intersection of mouth and narrow their embryo the intersection of development and the intersection of obstacle and reason differ, in the 6th week such as development such as embryo, the artery bes and begins to separate and become aorta and lung artery, begin to form the primitive tubercles of three valves in the membrane in of lung artery, and grow in, then absorb and change thinly and form three lung artery ones, such as the valve is growing up the obstacle is taking place in the course, merge and become a dome-shaped mouth mouth that break out in juncture of three leaves, namely form the lung artery one is narrow. In lung while of a development of artery, taper department of the intersection of heart and ball is absorbed and flows out dish (funnel department) as the right ventricle ,If development obstacle form, flow out dishes of plump ring muscle and loose the intersection of skin and bunch span the intersection of room and wall and form right ventricle, flow out dishes of narrow funnel type promptly among the interval. In addition in the embryo's development course, the 6th becomes the left, right lung artery to the development of arch of aorta, it carry until lung arteriolar to link far, near end link with pulmonary trunk, until the intersection of development and obstacle form pulse promptly artery branch or pulmonary trunk narrow.
Second, pathology change
The lung artery one is narrow: Merge dome-shapedly and increase the thick diaphragm in three pieces of leaf juncture, dash for ward it in, a hole takes the form of fish's mouth, can lie in the centre or lean to one side, a hole only 2- 3mm of the small one, generally a hole merges the place in juncture of a leaf about 5- 12mm, often leave a spine that slightly rises? ,Most cases and three leaves merge each other, a few is merged for one pair of leaves, petals of reason increase thick often, have the intersection of wart and little tubercle, can form calcified plague while being even, lung the intersection of artery and petals of ring have the one at various degrees to be narrow generally, because the right ventricle is loose because obstruct in blood flow, can produce and continue the taking place right ventricle and flow out the plump narrow and right room of a dish of fat to expand and cause the tricuspid valve not to close completely.
The pulse artery can be after appearing narrowly the shape of the shuttleless loom is expanded, can often extend to the left lung artery, it is obviously greater than the aorta that the lung artery is always dry.
The funnel one is narrow to present two types: First kind narrow for lack of mutual understanding type, below taper portion, right ventricle flow out line form fibrous muscle diaphragm among the wall bunch, scoundrel of ridge, at the one room, separate and become two hearts not of uniform size of the right ventricle, thin funnel department that expands of the wall is called the third ventricle above it, it is a plump right ventricle of muscle to play, the two separate by the membrane centre there is a narrow narrow passage, the size is invited among 3-15mm, it is often narrow with the artery valve that this kind of diaphragm type is narrow to coexist at the same time, it is narrow to call the phenotype. The second kind is narrow for pipeline type, mainly shown as the right ventricle flows out a wall one storey of filling the air muscles is plump, form one longer narrow the intersection of heart and of passway, narrow type this artery be development to be bad always with the intersection of lung and the intersection of artery and petals of ring and lung often, so expand after being not so narrow as lung artery.
Third, physiology change
No matter the lung artery port of that type is narrow, make the right ventricle arrange the blood and is obstructed, the pressure increases in the right ventricle, the range proportional to a narrow intensity of lung artery that increase. The pressure keeps normal or slightly drops in the lung artery, therefore the right room and steps a pressure rank in lung artery badly, its steps of pressure increase badly with a narrow intensity of lung artery, such as stepping a pressure rank badly in 5.3kPa( 40mmHg) The following is that slight the intersection of lung and the intersection of artery and mouth is narrow, arrange blood influence not big on the right heart, as stepping a pressure rank badly in 5.34- 13.33kPa (40- 100mmHg) Between belong to it is medium-sized by degrees of lung when being narrow in mouth in artery,it begin to be influenced for to last blood to rooms right, especially the right heart arranges blood volume to reduce when moving, act as and step one to press the steps and is greater than 13.33kPa( 100mmHg) badly The above right room arrange blood, obstruct obviously, even at quiet interest, right ventricle arrange blood volume see, reduce also, the load of right room obviously increases. It is long and as time passes, will impel right ventricular hypertrophy, so that the cardiac muscle of right room strains, the right ventricle expands leading to the fact the tricuspid valve ring will be expanded, produce the tricuspid valve relativity and can not close completely, then the pressure of atrium dextrum increases, the atrium dextrum is loose, when the pressure of atrium dextrum is higher than the pressure of atrium sinistrum, when not closing with the oval nest of the insula, can cause the blood to divide and flow into the atrium sinistrum from the atrium dextrum, central cyanosis appears on clinic, the load of long-term right ventricle increases, can cause the right heart to be depleted finally, symptoms such as intravenous anger one of neck, hepatomegaly, ascites and lower extremities edema,etc. appear
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