Exam 2 Flashcards
Which phase of the cardiac cycle is characterized by the ventricles relaxing and filling with blood, while the atrioventricular valves remain open?
a. Isovolumic Relaxation
b. Rapid Ventricular Filling
c. Slow Ventricular Filling (Diastasis)
d. Atrial Contraction (Atrial Systole)
c. Slow Ventricular Filling (Diastasis)
Explanation: During diastasis, the ventricles are in the phase of relaxation, and the atrioventricular valves (such as the mitral valve) are fully open. This allows blood to flow gradually from the atria to the ventricles.
What is the role of the atrioventricular (AV) node in the cardiac conduction system?
a. Generates a regular heartbeat
b. Transmits impulses from the SA node to the ventricles
c. Initiates ventricular contraction
d. Regulates blood flow to the coronary arteries
b. Transmits impulses from the SA node to the ventricles
Explanation: The AV node is responsible for transmitting electrical impulses that are initially generated by the SA (sinoatrial) node to the ventricles. It acts as a bridge between the atria and the ventricles, ensuring that the atria contract before the ventricles.
Which of the following compensatory mechanisms in heart failure increases the stretch of myocardial fibers and, subsequently, the force of contraction?
a. Sympathetic Nervous System
b. Frank-Starling Mechanism
c. Renin-Angiotensin-Aldosterone System (RAAS)
d. Parasympathetic Nervous System
b. Frank-Starling Mechanism
Explanation: The Frank-Starling Mechanism involves an increase in preload, which is the volume of blood that stretches the ventricles during the end-diastole when the heart is filled with blood. This increased preload results in the stretching of myocardial fibers and leads to a more forceful contraction, thereby increasing cardiac output.
A client with left-sided heart failure may present with which of the following clinical manifestations?
a. Peripheral edema
b. Liver congestion
c. Orthopnea
d. Syncope
c. Orthopnea
Explanation: Left-sided heart failure can lead to pulmonary congestion, which results in orthopnea. Orthopnea is a condition where a person experiences shortness of breath when lying flat and often needs to sit up or use extra pillows to breathe comfortably.
What is the most common cause of mitral valve regurgitation?
a. Age-related calcification
b. Coronary artery disease
c. Hypertrophic cardiomyopathy
d. Aortic stenosis
a. Age-related calcification
Explanation: Mitral valve regurgitation is often caused by the degeneration associated with aging, which leads to structural changes in the valve and its inability to close properly, allowing blood to flow backward into the left atrium.
In acute pulmonary edema, which of the following clinical manifestations is typically observed in the client’s respiratory status?
a. Hyperventilation
b. Absence of cough
c. Hypoxia and cyanosis
d. Elevated B-type natriuretic peptide (BNP) levels
c. Hypoxia and cyanosis
Explanation: Acute pulmonary edema is characterized by the accumulation of fluid in the lungs, which impairs proper gas exchange. This can lead to hypoxia (low oxygen levels in the blood) and cyanosis (bluish discoloration of the skin and mucous membranes) due to the inadequate oxygenation of tissues.
Which stage of heart failure is characterized by the presence of structural heart disease but no history of symptoms of heart failure?
a. Stage A
b. Stage B
c. Stage C
d. Stage D
b. Stage B
Explanation: Hypertrophic cardiomyopathy is characterized by left ventricular hypertrophy, which refers to the thickening of the walls of the left ventricle. This condition can lead to abnormal diastolic filling and left ventricular outflow obstruction.
In hypertrophic cardiomyopathy, what is the primary pathological change within the heart?
a. Right ventricular hypertrophy
b. Right atrial dilation
c. Left ventricular hypertrophy
d. Left atrial dilation
c. Left ventricular hypertrophy
Explanation: Hypertrophic cardiomyopathy is characterized by left ventricular hypertrophy, which refers to the thickening of the walls of the left ventricle. This condition can lead to abnormal diastolic filling and left ventricular outflow obstruction.
In the cardiac cycle, which phase corresponds to the contraction of the ventricles, leading to increased pressure and the closure of the atrioventricular valves?
a. Isovolumic Relaxation
b. Rapid Ventricular Filling
c. Isovolumic Contraction
d. Atrial Contraction
c. Isovolumic Contraction
Explanation: Isovolumic Contraction is the phase of ventricular contraction when the ventricles are generating pressure, leading to the closure of the atrioventricular valves (mitral and tricuspid) to prevent backflow of blood into the atria.
What is the primary goal of the Renin-Angiotensin-Aldosterone System (RAAS) in the context of heart failure?
a. Decrease blood pressure
b. Promote diuresis
c. Increase preload
d. Maintain blood volume
d. Maintain blood volume
Explanation: The primary goal of RAAS in heart failure is to maintain blood volume. When there is decreased perfusion to the kidneys, the RAAS is activated, leading to increased sodium and water retention, which helps to increase preload and, thus, maintain blood volume. This mechanism aims to improve cardiac output.
