Snell's - Thorax

Match the structures on the left with the regions of the heart on the right. (Each lettered region may be used more than once.) 1. Moderator band 2. Sinuatrial node 3. Bicuspid valve 4. Aortic vestibule A. Left ventricle B. Right ventricle C. Left atrium D. Right atrium E. Right side of membranous part of interventricular septum

1. B 2. D 3. A 4. A

A 4-year-old boy with cyanosis was examined by a pediatrician. The child had apparently become cyanotic during his 1st year of life. Since that time, sudden attacks of breathlessness had occurred on exertion. After a careful workup, a diagnosis of tetralogy of Fallot was made. In this congenital anomaly of the heart there are four cardiac defects. Which of the following is the most characteristic of the condition? A. Pulmonary stenosis with hypertrophy of the right ventricle B. Large atrial septal defect C. Hypertrophy of the left ventricle D. Stenosis of the aorta E. High blood pressure in the left ventricle

A

The following structure(s) may press against the esophagus during the passage of a barium meal except which? A. Left ventricle B. Left principal bronchus and aorta C. Margins of the esophageal opening in the diaphragm D. Muscular fibers of the lower end of the pharynx E. Left atrium

A

The following events occur on inhalation except which? A. The diaphragm descends. B. The external intercostal muscles contract. C. The abdominal muscles contract and push the abdominal viscera cranially. D. The ribs are raised. F. The vertical dimension of the thoracic cavity increases.

C

A patient was seen in the emergency department with a myocardial infarction. After a thorough clinical examination, including an electrocardiogram, it was concluded that the anterior interventricular branch of the left coronary artery was occluded. From the areas of the heart listed below select the one most likely to be involved. A. The entire diaphragmatic surface of the left ventricle B. The anterior part of the ventricular septum and the anterior (septal) papillary muscle of the left ventricle C. The posterior wall of the right atrium D. The atrioventricular bundle E. The right auricle

B

Pain arising in the heart is commonly referred to the following skin areas except which? A. Up into the neck and jaw B. Down the medial side of the arm C. The point of the shoulder D. The epigastric area E. Over the sternum

B

The conducting system of the heart is composed of the following structures except which? A. The Purkinje plexus B. The deep cardiac plexus C. The sinuatrial node D. The atrioventricular bundle E. The atrioventricular node

B

The following anatomic events occur at the level of the sternal angle (angle of Louis) except which? A. The right and the left pulmonary arteries enter the lungs. B. The right recurrent laryngeal nerve arises from the right vagus nerve. C. The trachea bifurcates. D. The ascending aorta becomes continuous with the arch of the aorta. E. The second costal cartilages articulate with the sternum.

B

The following statements concerning coarctation (narrowing) of the aorta are correct except which? A. The third to the eleventh posterior intercostal arteries have a diminished blood flow. B. The first and second posterior intercostal arteries will have a diminished blood flow. C. The narrowing of the aorta lies just proximal, opposite, or distal to the site of attachment of the ligamentum arteriosum. D. The narrowing takes place after birth. E. The condition is thought to result from contraction of ductus arteriosus muscle tissue.

B

The following statements concerning the bronchopulmonary segments are correct except which? A. It is a subdivision of a lung lobe. B. It is pyramidal in shape, with its apex toward the lung surface. C. It is surrounded by connective tissue. D. It has a segmental bronchus, a segmental artery, lymph vessels, and autonomic nerves. E. When diseased, it can be removed surgically as a structural unit.

B

The following statements concerning the diaphragm are correct except which? A. The diaphragm is a thin musculotendinous sheet that can be ruptured by extreme pressure applied from below. B. On contraction, the diaphragm increases the intrathoracic pressure. C. The right crus provides a sphincter-like mechanism for the esophagus. D. On contraction, the diaphragm assists in the return of venous blood to the right atrium and of lymph to the thoracic duct. E. When viewed from in front, the central tendon of the diaphragm lies behind the xiphisternal joint.

B

The following statements concerning the lungs are correct except which? A. Each lung is very elastic, and should the thoracic cavity be opened by a stab wound, the lung shrinks to one third or less in volume. B. The cardiac notch lies in the lower lobe of the left lung. C. The visceral pleura covering each lung lines the fissures that are situated between the lobes. D. The apex of each lung extends up into the root of the neck and lies anterior to the lower roots of the brachial plexus. E. The bronchi, connective tissue, and visceral pleura of the lungs are supplied by the bronchial arteries.

B

The following statements concerning the structure of the heart are correct except which? A. The trabeculae carneae are internal surface structures of both the left and the right ventricles. B. The pericardial cavity is the potential space between the fibrous and the serous pericardia. C. The coronary arteries are functional end arteries. D. The sinuatrial node is supplied by the right and sometimes the left coronary artery. E. The four pulmonary veins open through the posterior wall of the left atrium and there are no valves.

B

The following statements regarding the innervation of thoracic structures are correct except which? A. The lung and visceral pleura are innervated by the autonomic nerves and are not sensitive to sensations of temperature, touch, and pressure. B. The motor innervation of the diaphragm is provided by the third, fourth, and fifth cervical spinal nerves and by the lower six intercostal nerves. C. The sensory nerve supply to the mucous membrane of the lower part of the trachea is from the vagus and the recurrent laryngeal nerves. D. The nerve supply of the pericardium is the phrenic nerves. E. The sinuatrial node is supplied by sympathetic and parasympathetic nerves via the cardiac plexuses.

B

A 35-year-old woman was seen in the emergency department after an automobile accident. While driving her car, she had been wearing a lap belt but without the shoulder strap; she hit a utility pole head-on. Examination of the thoracic cage revealed a fracture of the body of the sternum and of the third and the fourth left ribs. In such an accident, the patient's age may play a large role in the extent of anatomic injury. Which of the following statements accounting for this fact is likely to be correct? A. The increased elasticity of fibrous structures in elderly people. B. The highly flexible rib cage in children. C. The ossification of the xiphoid cartilage that occurs with age .

B.

The following anatomic facts regarding the right coronary artery are correct except which? A. It gives rise to a marginal branch. B. It passes forward between the right auricle and the pulmonary trunk. C. It gives rise to an anterior interventricular branch. D. It arises from the anterior aortic sinus. E. It descends in the right atrioventricular groove.

C

The following important structures are in the region of the thoracotomy incision except which one? A. The internal thoracic artery B. The intercostal nerve C. The superior epigastric artery D. The intercostal artery F. The intercostal vein

C

A 22-year-old man was seen in the emergency department after a street shootout. The patient showed signs of severe hemorrhagic shock. A small entrance wound was found in the third left intercostal space approximately 1 in. (2.5 cm) from the lateral margin of the sternum, but there was no exit wound. The left side of his thorax was dull on percussion, and breath sounds were absent on that side of the chest. It was decided to open the chest (thoracotomy) through the fourth left intercostal space, after which it was found that the left atrium had been perforated by the bullet. When the thoracotomy incision was made to enter the pleural cavity, the following structures were incised except for which one? A. The skin and subcutaneous tissue B. The pectoral muscles and the serratus anterior muscle C. The latissimus dorsi muscle D. The external intercostal muscle and the anterior intercostal membrane E. The internal intercostal and innermost intercostal muscles F. The endothoracic fascia and the parietal pleura

C

With aging, the following detrimental changes occur in the thorax except which? A. The ribs and the costal cartilages become more rigid. B. The elastic tissue in the lungs tends to degenerate. C. The manubriosternal joint becomes more mobile. D. The thoracic and the abdominal muscles tend to atrophy. E. The xiphoid process becomes ossified.

C

The following statements concerning the heart are correct except which? A. The first sound of the heart is lub and is produced by the contraction of the ventricles and the closure of the tricuspid and mitral valves. B. The second shorter sound of the heart is du p, which is produced by the sharp closure of the aortic and pulmonary valves. C. The pulmonary valve has two semilunar cusps. D. The left atrium lies posterior to the right atrium. E. The apex beat of the heart is best felt by asking the patient to sit up and lean forward.

C.

During fetal life, the following facts regarding the circulatory system are correct except which? A. The blood passing through the foramen ovale is more oxygenated than that passing through the right atrioventricular orifice. B. The direction of blood flow through the ductus arteriosus is from right to left. C. The ductus venosus permits blood to bypass the liver. D. The blood in the abdominal aorta is relatively more oxygenated than that in the internal carotid arteries. E. The valve of the inferior vena cava deflects blood toward the foramen ovale

D

A patient is examined in the standing position with a left-sided pleurisy. Where would you expect the pleural fluid to gravitate down to? A. The oblique fissure B. The cardiac notch C. arch of the aorta. D. The costodiaphragmatic recess E. The horizontal fissure

D

A patient was admitted into hospital with acute pericarditis. Because the movements of the heart were compromised by the excess of fluid in the pericardial cavity, and the cause of the infection was unknown, it was decided to perform a pericardiocentesis. A specimen of the fluid was kept for bacteriological examination. Pericardiocentesis is best performed by passing a needle through A. the fourth intercostal space. B. the sixth intercostal space at the left paravertebral border. C. the second intercostal space at the midclavicular line. D. the subcostal angle. E. the second intercostal space at the right sternal angle.

D

The following statements concerning an intercostal space are correct except which? A. The anterior intercostal arteries of the lower five intercostal spaces are branches of the musculophrenic artery. B. The sensory fibers in the lower five intercostal nerves supply the skin of the lateral thoracic and anterior abdominal walls. C. The posterior intercostal arteries of the lower nine spaces are branches of the thoracic aorta. D. Throughout an intercostal space, the intercostal nerves and blood vessels lie close to the upper border of the lower rib. E. The intercostal nerves and blood vessels run between the internal and the innermost intercostal muscles.

D

The following statements concerning the positions of thoracic structures at different phases of respiration are correct except which? A. The trachea bifurcates opposite the manubriosternal angle in the midrespiratory position. B. On full inspiration, the lower margin of the left lung could extend down the midclavicular line to the eighth costal cartilage. C. The lower margin of the right lung in the midclavicular line could cross the sixth rib in the midrespiratory position. D. The apex of the heart can usually be felt in the sixth left intercostal space in the midrespiratory position. E. On full expiration the right dome of the diaphragm may extend up as far as or beyond the upper border of the fifth rib.

D

The following statements concerning thoracic structures are correct except which? A. The carina is the name given to the site of bifurcation of the trachea. B. The ligamentum arteriosum is the remains of theductus arteriosus. C. The ductus arteriosus is formed from the sixth left pharyngeal arch. D. The thymus lies in the middle mediastinum. E. The thymus receives its arterial supply mainly from the internal thoracic arteries.

D

When passing a needle through the chest wall and into the pleural cavity in the midaxillary line, the following structures will be pierced except which? A. The external intercostal muscle B. The skin C. The parietal pleura D. The levator costarum E. The internal intercostal muscle

D

60. A patient was seen in the Emergency Department in cardiac arrest. During cardiopulmonary resuscitation the posterior surface of the heart was compressed by which of the following structures? A. The body of the sternum B. The heads of the ribs C. The tracheal bifurcation D. The inferior vena cava E. The bodies of the vertebrae

E

The following statements concerning the main bronchi are correct except which? A. The right main bronchus is wider than the left main bronchus. B. The right main bronchus is shorter than the left main bronchus. C. The right main bronchus is more vertical in position than the left main bronchus. D. The left main bronchus passes to the left in front of the esophagus. E. The left main bronchus gives off the superior lobar bronchus before entering the hilum of the lung.

E

The following statements concerning the right tracheo-bronchial lymph nodes are correct except which? A. They could become enlarged as the result of invasion of malignant tumor cells from the middle lobe of the right lung. B. They could become enlarged as the result of invasion of malignant tumor cells from the inferior lobe of the right lung. C. They are situated alongside the trachea and the bronchi. D. They drain lymph from the lower end of the trachea. E. They do not drain lymph from the heart.

E

The following structures open into the right atrium except which? A. The superior vena cava B. The coronary sinus C. The anterior cardiac vein D. The inferior vena cava E. The right pulmonary veins

E

A 35-year-old woman was seen in the emergency department after an automobile accident. While driving her car, she had been wearing a lap belt but without the shoulder strap; she hit a utility pole head-on. Examination of the thoracic cage revealed a fracture of the body of the sternum and of the third and the fourth left ribs. In this case, the following structure(s) located behind the body of the sternum and the left ribs could have been injured except which one(s)? A. The pericardium B. The right ventricle of the heart C. The right atrium of the heart D. The left ventricle of the heart E. The phrenic nerves F. The esophagus

F