CV Physiology: Cardiac Function Flashcards
The T wave of the electrocardiogram begins to occur during
A) early diastole
B) isovolumetric contraction
C) isovolumetric relaxation
D) systolic ejection
D) systolic ejection
Closure of the aortic and pulmonic valves produces which heart sound?
A) S1
B) S2
C) S3
D) S4
B) S2
Using the Fick Principle, cardiac output can be calculated by
A) dividing the arterial-venous pressure difference by the systemic vascular resistance
B) dividing the whole body oxygen consumption by the arterial-venous oxygen content difference
C) multiplying the stroke volume and heart rate
D) multiplying the whole body oxygen consumption and the arterial-venous oxygen content difference
B) dividing the whole body oxygen consumption by the arterial-venous oxygen content difference
Compared to a normal left ventricular pressure-volume loop (grey), the red loop indicated by the arrow represents the independent effects of
A) decreased inotropy
B) decreased preload
C) decreased afterload
D) increased preload
A) decreased inotropy
The maximal rate of pressure development within the left ventricle occurs
A) during isovolumetric contraction
B) during rapid ventricular ejection
C) at peak left ventricular systolic pressure
D) during rapid ventricular filling
A) during isovolumetric contraction
Compared to a normal left ventricular pressure-volume loop (grey), the red loop indicated by the arrow represents
A) increased preload, afterload, and inotropy
B) increased inotropy and afterload, and decreased preload
C) increased stroke volume with increased end-systolic volume
D) increased stroke volume and decreased ejection fraction
B) increased inotropy and afterload, and decreased preload
In the figure, left ventricular stroke volume is plotted against left ventricular end-diastolic volume. Relative to the normal control point, which one of the following points represents the independent effects of a decrease in afterload?
Point A
Point B
Point C
Point D
Point A
When the left ventricular stroke volume is 40 mL/beat and the heart rate is 80 beats/minute, the cardiac output is
A) 2 liters/minute
B) 3.2 liters/minute
C) 5 liters/minute
B) 3.2 liters/minute
Ventricular preload is increased in response to
A) decreased atrial contractility
B) decreased blood volume
C) decreased ventricular inotropy
D) increased venous compliance
C) decreased ventricular inotropy
Compared to a normal left ventricular pressure-volume loop (grey), the red loop indicated by the arrow represents the independent effects of
A) decreased preload
B) increased afterload
C) increased inotropy
D) increased preload
B) increased afterload
The mitral valve normally opens at the beginning of diastolic filling because
A) left atrial contraction forces open the valve
B) left ventricular pressure falls below the left atrial pressure
C) the papillary muscles contract
D) the papillary muscles relax
B) left ventricular pressure falls below the left atrial pressure
In the figure, left ventricular stroke volume is plotted against left ventricular end-diastolic volume. Relative to the normal control point, which one of the following points represents the independent effects of a decrease in blood volume?
Point A
Point B
Point C
Point D
Point C
Blood flow across a normal heart valve normally generates only a very small pressure gradient because valve resistance is very low.
True
False
True
The following figure represents a normal left ventricular pressure-volume loop. The arrow is pointed to what event in the cardiac cycle?
A) aortic valve opening
B) end-systolic volume
C) end of systolic ejection
D) mitral valve opening
A) aortic valve opening
Ventricular systole is defined as the time between the
A) closing of the aortic valve and the opening of the mitral valve
B) closing of the mitral valve and the closing of the aortic valve
C) opening and closing of the aortic valve
D) opening of the aortic valve and the opening of the mitral valve
B) closing of the mitral valve and the closing of the aortic valve
