CVS Review Quiz: Exam!

The correct answer is the sequence: SA node —> atrioventricular (AV) node —> bundle of His —> bundle branches —> Purkinje fibers. This is the normal sequence of conduction within the heart, starting with the SA node, which is the natural pacemaker of the heart. The electrical signal then travels to the AV node, which acts as a delay before transmitting the signal to the bundle of His. From there, the signal is conducted through the bundle branches and finally reaches the Purkinje fibers, which distribute the signal throughout the ventricles, causing them to contract.

Visible jugular vein pulsation in the neck is indeed an indicator for right-sided heart failure (HF). Right-sided HF occurs when the right side of the heart is unable to pump blood effectively, leading to a backup of blood in the veins. This can cause increased pressure in the jugular veins, leading to their visible pulsation. Therefore, if jugular vein pulsation is visible in the neck, it suggests that there may be right-sided HF present.

Dextrocardia is a condition where the heart is positioned on the right side of the chest instead of the left. This is considered abnormal because the heart is typically located on the left side. Dextrocardia can sometimes be associated with other congenital heart defects or abnormalities.

The truncus arteriosus becomes the aorta and pulmonary artery. During fetal development, the truncus arteriosus is a single vessel that emerges from the heart and carries both oxygenated and deoxygenated blood. As the heart develops further, the truncus arteriosus divides into two separate vessels - the aorta, which carries oxygenated blood to the body, and the pulmonary artery, which carries deoxygenated blood to the lungs. This division allows for the separation of oxygenated and deoxygenated blood, ensuring proper circulation throughout the body.

Cardiac biomarkers are substances released into the bloodstream when there is damage to the heart muscle. In the case of NSTEMI (non-ST elevation myocardial infarction), there is evidence of cardiac injury, which can be detected by elevated levels of cardiac biomarkers such as troponin. Unstable angina, on the other hand, does not cause significant cardiac damage, so the levels of cardiac biomarkers would not be elevated. Therefore, differentiating between NSTEMI and unstable angina can be done by measuring cardiac biomarkers. The other options mentioned (ECG, stress test, and catheter) may provide additional information but are not specific for distinguishing between NSTEMI and unstable angina.

During the phase of rapid ventricular filling, the mitral valve is open. This allows blood to flow from the left atrium into the left ventricle. The mitral valve acts as a one-way valve, preventing backflow of blood into the atrium during ventricular contraction. The opening of the mitral valve is essential for proper filling of the ventricle and subsequent pumping of blood to the rest of the body.

The correct answer is c3, c4, c5. These spinal roots innervate the pericardium, which is the fibrous sac that surrounds the heart. The nerves originating from these spinal roots supply sensory information to the pericardium, allowing for the perception of pain or other sensations in this area.

Orthopnea is the correct answer because it refers to the medical condition of experiencing shortness of breath when lying down. This condition is commonly seen in individuals with heart or lung problems, as lying flat can increase fluid accumulation in the lungs, making it difficult to breathe. Orthopnea can be relieved by sitting up or propping oneself with pillows while sleeping.

In fetal circulation, the direction of flow in the ductus arteriosus is from right to left. This is because the ductus arteriosus is a blood vessel that connects the pulmonary artery to the aorta, bypassing the lungs. As the lungs are not fully functional in the fetus, the blood needs to be shunted away from the lungs and directly to the body. Therefore, the blood flows from the right side of the heart to the left side through the ductus arteriosus.

The umbilical vein is the most oxygenated fetal circulatory structure. This is because it carries oxygenated blood from the placenta to the fetus, providing the necessary oxygen and nutrients for fetal development. The other options, such as the aorta, vena cava, and umbilical artery, carry deoxygenated blood or blood with lower oxygen content.

The given answer is "first degree heart block" because the patient's symptoms suggest a delay in the conduction of electrical signals from the atria to the ventricles, which is characteristic of first degree heart block. This condition is usually benign and does not require immediate treatment, but regular monitoring is recommended to ensure it does not progress to a more severe form of heart block.

A warm skin is an indicator of distributive shock. Distributive shock occurs when there is widespread vasodilation, causing blood to pool in the peripheral tissues and reducing blood flow to vital organs. This results in the skin feeling warm to the touch. Cardiogenic shock is characterized by poor heart function, neurogenic shock is caused by damage to the nervous system, and hypovolemic shock is due to a decrease in blood volume. None of these types of shock would typically result in warm skin.

The given ECG rhythm strip shows a complete dissociation between P waves and QRS complexes, indicating that the atria and ventricles are not communicating properly. The atrial rate of 95 beats/min and regularity suggests that the atria are functioning normally. However, the ventricular rate of about 60 beats/min and regularity indicates that the ventricles are not receiving all the atrial impulses. This pattern is consistent with third-degree AV nodal block, where there is complete blockage of electrical impulses between the atria and ventricles. Premature ventricular complexes would be indicated by abnormal QRS complexes, which is not the case here.

Continuous (Type 1) capillaries are characterized by their tight junctions and continuous endothelial lining. These capillaries are found in most tissues of the body, including muscle, lung, and skin. However, the liver does not have continuous capillaries. Instead, it has discontinuous (Type 2) capillaries, also known as sinusoidal capillaries. These capillaries have large gaps between endothelial cells, allowing for the passage of larger molecules such as proteins and blood cells. This unique structure of liver capillaries is necessary for the liver's function in filtering and processing blood.

Increased blood PCO2 can cause tachycardia because it is a sign of respiratory acidosis, which occurs when there is an increase in carbon dioxide levels in the blood. This triggers a compensatory response by the body to increase heart rate in order to improve oxygen delivery and remove excess carbon dioxide.

Isovolumetric contraction refers to the phase of the cardiac cycle where the ventricles contract without any change in volume. During this phase, the pressure in the ventricles rises rapidly, causing the closure of the atrioventricular valves and the opening of the semilunar valves. The c' wave in the right atrium corresponds to the contraction of the atrium just before the closure of the atrioventricular valves. Therefore, it is closely associated with isovolumetric contraction. The second heart sound and the P wave of the ECG are not directly related to isovolumetric contraction.

Increasing the inotropic state of the myocardium refers to increasing the contractility of the heart muscle. This results in a stronger contraction and increased force of contraction. When the force of contraction is increased, the pressure-volume loop, which represents the relationship between pressure and volume in the heart during a cardiac cycle, becomes wider. This indicates that more work is being done by the heart, leading to an increased stroke volume and cardiac output. Therefore, the correct answer is that increasing the inotropic state of the myocardium will increase the width of the pressure-volume loop.

The presence of ST elevation and Q wave in lead II, III, and AVF suggests occlusion in the Left Circumflex artery (LCx) and Right Coronary Artery (RCA). These changes in the electrocardiogram (ECG) indicate ischemia or damage to the inferior wall of the heart, which is supplied by these arteries. The Left Anterior Descending artery (LAD) and Left Coronary Artery (LCA) are not implicated in this scenario.