Block 3 Hemodynamic Acad Success Sem1

The stroke volume is the difference between the end diastolic volume and the end systolic volume, which is calculated by subtracting the end systolic volume (60ml) from the end diastolic volume (110ml). Therefore, the stroke volume is 50ml.

The cardiac output of a person is calculated by multiplying the stroke volume (the difference between end diastolic volume and end systolic volume) by the heart rate. In this case, the stroke volume is 110ml - 60ml = 50ml. The heart rate is given as 80 beats/min. Therefore, the cardiac output can be calculated as 50ml * 80 beats/min = 4000ml/min, which is equal to 4 L/min.

The sinus venarum is a region of the heart that receives deoxygenated blood from the systemic circulation. It is formed by the right sinus horn during embryonic development. The right sinus horn is one of the regions of the embryonic heart tube, along with the left sinus horn, bulbus cordis, primitive atrium, and truncus arteriosus. Therefore, the correct answer is right sinus horn.

The correct answer is transposition of the great vessels. Transposition of the great vessels is a congenital heart defect where the aorta arises from the right ventricle and the pulmonary trunk arises from the left ventricle. This results in the oxygenated blood from the lungs being recirculated back to the lungs, while the deoxygenated blood from the body is recirculated back to the body. This condition leads to cyanotic heart disease and failure to thrive in newborn infants.

The given data includes the values for systolic pressure, diastolic pressure, heart rate, and stroke volume. Cardiac output can be calculated by multiplying stroke volume by heart rate. In this case, the stroke volume is given as 50 ml and the heart rate is given as 80 bpm. Multiplying these values gives a cardiac output of 4000 ml/min or 4.0 L/min. However, the given answer states that the cardiac output is 4.8 L/min. Since this value is not directly provided in the given data, it is unclear how it was calculated. An explanation for this discrepancy is not available.

(110-60)/110 = 45

The fetal cardiovascular system has three shunts: the ductus venosus, the foramen ovale, and the ductus arteriosus. These shunts allow blood to bypass certain areas of the fetal circulation that are not fully developed or necessary for fetal survival. The ductus venosus shunts oxygenated blood from the umbilical vein directly to the inferior vena cava, bypassing the liver. The foramen ovale allows blood to flow from the right atrium to the left atrium, bypassing the non-functioning fetal lungs. The ductus arteriosus shunts blood from the pulmonary artery to the aorta, bypassing the non-functioning fetal lungs.

The region of the heart tube that contributes to the aortic arch arteries is the truncus arteriosus. The truncus arteriosus is a part of the developing heart tube that gives rise to the aortic arches, which eventually form the major arteries that supply blood to the head and neck. The bulbus cordis, primitive atrium, primitive ventricle, and sinus venosus are other regions of the heart tube that contribute to different structures in the developing heart, but not specifically to the aortic arch arteries.

Patent ductus arteriosis is common and probably asymptomatic

Continuous capillaries do not have fenestrations (small pores) in the endothelial cells. Fenestrations are found in fenestrated capillaries, not in continuous capillaries. Continuous capillaries have a complete endothelial lining, with all endothelial cells resting on a basal lamina. Substances are transported across the wall of continuous capillaries by pinocytosis, and the endothelial cells are connected to each other by tight junctions. Pericytes can be found around continuous capillaries, providing support and contractile function.

The right sinus horn is the region of the embryonic heart tube that gives rise to the sinus venarum. The sinus venarum is a smooth-walled portion of the right atrium that receives blood from the systemic circulation. It is formed from the incorporation of the right sinus horn into the developing heart. The bulbus cordis gives rise to the right ventricle and part of the left ventricle, the primitive atrium gives rise to the left atrium, and the truncus arteriosus gives rise to the aorta and pulmonary trunk.

Metarterioles are small blood vessels that connect arterioles to capillaries. They possess precapillary sphincters, which are small bands of smooth muscle located at the junction between metarterioles and capillaries. These sphincters can constrict or relax to regulate blood flow into the capillaries. This allows for precise control of blood distribution and ensures that tissues receive an adequate blood supply based on their metabolic needs. The other statements are incorrect because metarterioles do not possess valves, do not have a complete layer of smooth muscle cells in their tunica media, and do not have an external elastic lamina.

Smooth muscle cells of the tunica media of an artery cannot secrete anticoagulants. Smooth muscle cells are responsible for regulating the diameter of blood vessels, which can affect blood pressure. They also secrete collagen and elastic fibers to provide structural support to the artery. Additionally, smooth muscle cells can repair the tunica intima after injury. However, the secretion of anticoagulants is not a function of smooth muscle cells in the tunica media.

The most likely cause of the findings described in the question is a ventricular septal defect (VSD). VSD is a congenital heart defect characterized by an abnormal opening in the septum (wall) between the two ventricles of the heart. This can lead to a left-to-right shunt, causing oxygen-rich blood from the left ventricle to flow back into the right ventricle. The higher than expected oxygen level in the right ventricle seen during cardiac catheterization supports this diagnosis. The symptoms of fatigue, along with the presence of a pansystolic murmur at the lower left to mid left sternal border, are consistent with VSD as well.

The lymphatic capillaries do not drain into blood capillaries. Instead, they drain into larger lymphatic vessels, which eventually empty into the bloodstream through the thoracic duct or the right lymphatic duct.

The ductus venosus is a blood vessel that connects the umbilical vein to the inferior vena cava, allowing oxygen-rich blood from the placenta to bypass the liver and flow directly to the heart. This means that the blood in the ductus venosus has the highest level of oxygen compared to the other locations mentioned.

Patent ductus arteriosus is the most common malformation of the heart and great vessels. This condition occurs when the ductus arteriosus, a blood vessel that connects the pulmonary artery to the aorta in a developing fetus, fails to close after birth. This results in abnormal blood flow between the two major blood vessels, leading to symptoms such as heart murmurs, difficulty breathing, and poor weight gain. Treatment options for patent ductus arteriosus include medication and surgical closure of the ductus arteriosus.

the key word her is INTACT

Persistent truncus arteriosus is a congenital heart defect that occurs when the neural crest cells fail to properly form during development. Neural crest cells play a crucial role in the formation of the heart and blood vessels. In this defect, a single large blood vessel, known as the truncus arteriosus, fails to divide into the pulmonary artery and aorta, leading to mixing of oxygen-rich and oxygen-poor blood. This can result in poor oxygenation of the body and can be life-threatening if not treated.

Capillaries are the primary site in the body where oxygen is transferred from the blood to the tissues. Pericytes can be found closely associated with capillaries. Permeability of capillaries can be altered by histamine. Capillaries carry out lipolysis of lipoproteins. However, the statement that a somatic capillary contains fenestrae in it is incorrect. Fenestrae are small pores or openings that are found in certain types of capillaries, such as the ones in the kidneys and endocrine glands, but not in somatic capillaries.

The most likely diagnosis in this case is patent ductus arteriosus. This condition is characterized by a persistent opening between the pulmonary artery and the aorta, known as the ductus arteriosus, which normally closes shortly after birth. The continuous murmur heard on auscultation is consistent with the blood flow through the patent ductus arteriosus. The higher arterial blood oxygen content in the right hand compared to the left hand suggests that oxygenated blood from the aorta is mixing with deoxygenated blood from the pulmonary artery. X-rays of the chest showing no abnormalities further supports this diagnosis.

The absence of a ventral double-fold of coelomic membrane connecting the heart to the ventral body wall (a ventral mesocardium) is a result of a bilateral connection of the early intraembryonic coelom rostral to the developing heart.

The venae cavae are large veins that return deoxygenated blood from the body back to the heart. The development of the venae cavae involves the fusion and remodeling of several embryonic veins. The right vitelline vein, right common cardinal vein, right posterior cardinal vein, and right anterior cardinal vein are all involved in the development of the venae cavae. However, the right subcardinal vein is not involved in this process.