Quiz 23: Antianginal Drugs
The electrocardiogram or ECG are very important in determining the cardiac rhythm and conduction. The heart rate can be determined by counting the number of QRS waves in a minute and the normal range is between 60-100 beats per minute. There are three ECG intervals namely PR, QRS and QT intervals depending upon the part of the wave generated in the ECG. The duration of PR interval refers to conduction from SA node to AV node. The duration of QRS interval refers to the time of depolarization or influx of sodium ion and the conduction through the ventricles of the heart. The QT interval includes the QRS interval as well as the re-polarization of the ventricles. When the patient develops arrhythmia or the rhythm of heart is disturbed then the proper working of the heart and the movements of the ions in the heart is disturbed. Such as the heart beat rate increases and the patient develops tachycardia and it can be due to short QRS interval or QT interval. In any such case where the wave interval is disturbed and working of heart is not in normal range then there is need to support heart with anti-arrhythmic drugs.
According to the data given in the case study patient had undergone knee replacement surgery. It is probable that the patient must be given pain killers and muscle relaxants. He was diagnosed with ventricular arrhythmia on the 2 nd day of surgery. Thus, the physician prescribed Norpace to the patient. The drug Disopyramide is sold under the trade name of Norpace. It is an anti-arrhythmic medication used for the treatment of ventricular tachycardia. Now, the patient complains of urinary difficulties that can be due to interaction of muscle relaxants and Norpace. The side effects of muscle relaxants include difficulty in urination, dryness in mouth, tiredness, dizziness and headache.
The depolarization of ventricular muscle occurs in the different chambers of the heart such as atrium and the ventricle. The movement of sodium ions out of the cell is not associated with the depolarization of ventricular muscle. The movement of sodium ions into the cell may show such act. Hence, (a) is an incorrect answer. The depolarization of ventricular muscle is not associated with the movement of potassium ions. It gets affected by the sodium ion movement. Hence, (b) is an incorrect answer. The calcium ions do not affect the depolarization of ventricular muscle. The sodium ions show an effect on the depolarization. Hence, (d) is an incorrect answer. The potassium does not bring about the depolarization of ventricular muscle. The movement of sodium ions is related with the depolarization of ventricular muscle. Hence, (d) is an incorrect answer. The movement of sodium ions is associated with the depolarization of ventricular muscle. The movement of sodium ions into the cell results in depolarization of ventricular muscle that can be noticed with the changes occurring in the different chambers of a heart. Hence, is correct.
There is no answer for this question