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Chapter 18. Toxic Responses of the Heart and Vascular System
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In which of the following locations would one NOT find spontaneous depolarization?
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Which of the following scenarios would increase contractility of the myocardium?
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a. increased activity of the Na+/K+-ATPase.
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b. increased activity of sacroplasmic reticulum Ca2+ ATPase.
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c. decreased activity of sacroplasmic reticulum Ca2+ ATPase.
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d. decreased intracellular calcium levels.
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e. increased intracellular K+ levels.
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All of the following statements regarding abnormal cardiac function are true EXCEPT:
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a. Ventricular arrhythmias are generally more severe than atrial arrhythmias.
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b. Ventricular hypertrophy is a common cause of ventricular arrhythmias.
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c. Coronary artery atherosclerosis is a major cause of ischemic heart disease.
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d. Right-sided heart failure results in pulmonary edema.
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e. Tachycardia is classified as a rapid resting heart rate (>100 beats/min).
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Ion balance is very important in maintaining a normal cardiac rhythm. Which of the following statements is TRUE?
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a. Blockade of K+ channels decreases the duration of the action potential.
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b. Blockade of Ca2+ channels has a positive inotropic effect.
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c. Inhibition of Na+ channels increases conduction velocity.
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d. Blockage of the Na+/K+-ATPase increases contractility.
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e. Calcium is transported into the cell via a Ca2+-ATPase.
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Which of the following is most likely NOT a cause of myocardial reperfusion injury?
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a. cellular pH fluctuations.
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b. damage to the sarcolemma.
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c. generation of toxic oxygen radicals.
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e. inhibition of the electron transport chain.
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Which of the following statements regarding the cardiotoxic manifestations of ethanol consumption is FALSE?
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a. Acute ethanol toxicity causes decreased conductivity.
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b. Chronic alcohol consumption is associated with arrhythmias.
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