Cardiac Anatomy
This structure separates the left and right atria and contains the remnant of the fetal foramen ovale.
What is the interatrial septum?
A lesion compresses this structure passing through the pulmonary hilum that carries parasympathetic fibers responsible for bronchoconstriction and increased glandular secretion.
What is the vagus nerve?
A patient develops a sudden increase in sympathetic activity. What two major effects would this have on the heart's chronotropy and inotropy?
What are increased heart rate (positive chronotropy) and increased contractility (positive inotropy)?
A patient takes a very deep breath. Which lung volume increases, and which respiratory volume remains unchanged because it cannot be voluntarily exhaled?
What are tidal volume and residual volume?
During cardiac development, the primitive atrium is divided into right and left atria by two overlapping septa. What fetal opening allows blood to pass from the right atrium to the left atrium before birth?
What is the foramen ovale?
This papillary muscle is particularly vulnerable to ischemia because it typically receives its blood supply from only one coronary artery.
What is the posteromedial papillary muscle?
A patient aspirates a small object while eating. Based on the anatomy of the main bronchi, which bronchus is the object most likely to enter?
What is the right main bronchus?
If the PR interval on an ECG becomes prolonged because conduction through the AV node slows, what important physiological function of the AV node is responsible for allowing the ventricles time to fill?
What is the AV nodal delay, which allows additional ventricular filling before ventricular contraction?
A patient develops airway obstruction that makes it difficult to exhale. Which pulmonary function test value would be expected to decrease disproportionately compared with another major measure of airflow?
What is the FEV₁/FVC ratio?
The respiratory system develops primarily from which embryonic germ layer?
What is the endoderm?
This artery usually gives rise to the artery that supplies the SA node and travels in the coronary sulcus toward the right side of the heart.
What is the right coronary artery?
This nerve provides motor innervation to the diaphragm and travels through the thorax along the lateral surface of the pericardium.
What is the phrenic nerve?
A patient experiences a significant decrease in arterial blood pressure. Baroreceptors in the carotid sinus detect this change. What happens to sympathetic activity, heart rate, and systemic vascular resistance?
What are increased sympathetic activity, increased heart rate, and increased systemic vascular resistance?
A patient travels from sea level to a high altitude where atmospheric pressure is significantly lower. What happens to the partial pressure of inspired oxygen, and how does this affect the driving force for oxygen diffusion into the blood?
What are decreased inspired PO₂ and decreased driving force for oxygen diffusion?
The ductus arteriosus allows fetal blood to bypass the nonfunctioning lungs. After birth, it normally closes and becomes what structure?
What is the ligamentum arteriosum?
This cardiac structure forms most of the anterior surface of the heart and lies immediately posterior to the sternum.
What is the right ventricle?
A patient develops unilateral vocal cord paralysis after surgery near the aortic arch. Which nerve was most likely injured, and around which structure does it loop?
What is the left recurrent laryngeal nerve, which loops under the aortic arch near the ligamentum arteriosum?
A patient has an increase in afterload while preload and contractility remain constant. What happens to end-systolic volume and stroke volume?
What are increased end-systolic volume and decreased stroke volume?
A patient has destruction of alveolar walls, resulting in decreased elastic recoil of the lungs. What condition does this describe, and what happens to the work of expiration?
What is emphysema, with increased difficulty with expiration due to loss of elastic recoil?
This embryonic structure divides the primitive heart tube into the future right and left ventricles.
What is the interventricular septum?
A thrombus obstructs the artery running in the anterior interventricular sulcus. Which two major regions of the heart would be most directly affected by this obstruction?
What are the anterior walls of the ventricles and the anterior two-thirds of the interventricular septum?
A patient has a mass compressing the esophagus within the posterior mediastinum. The mass also affects a nearby structure responsible for carrying lymph from most of the body below the diaphragm toward the venous system. What structure is most likely being compressed
What is the thoracic duct?
A patient has an abnormally stiff left ventricle. During diastole, the ventricle requires a much higher pressure to accommodate the same volume of blood. Which phase of the cardiac cycle is primarily affected, and what happens to ventricular compliance?
What is ventricular diastole, with decreased ventricular compliance?
A patient has a pulmonary embolism that blocks blood flow to a group of alveoli. The alveoli continue to receive air but receive little or no blood. What happens to the V/Q ratio in the affected region, and what type of physiological dead space is created?
What are an increased V/Q ratio approaching infinity and increased alveolar dead space?
During embryonic development, the trachea and esophagus begin as one tube. What embryonic structure separates them into two distinct passages?
What is the tracheoesophageal septum?