A nurse is teaching the partner of a client who had an acute myocardial infarction (MI) about the reason blood was drawn from the client. Which of the following statements should the nurse make regarding cardiac enzyme studies?

The nurse should instruct the client to adjust the thermostat so that the environment is warm because cold temperatures can cause vasoconstriction and worsen the symptoms of PAD, such as pain, numbness, and poor wound healing. The client should also avoid exposure to cold weather and wear warm clothing.

1. Apply a heating pad on a low setting to help relieve leg pain is wrong because it can cause burns, vasodilation, and increased blood flow to the legs, which can increase the risk of bleeding and edema in PAD.
2. Wear antiembolic stockings during the day is wrong because they can impair arterial circulation and cause ischemia and tissue damage in PAD. Antiembolic stockings are used to prevent venous thromboembolism, not arterial disease.

Rest with the legs above heart level is wrong because it can decrease arterial blood flow to the legs and worsen ischemia and pain in PAD. The client should rest with the legs at or below heart level to promote arterial circulation.

The P wave is the first wave on the ECG strip and represents the electrical activity of the atria. It reflects the depolarization of the atrial myocardium, which is the process of changing the electrical charge of the cardiac cells from negative to positive, triggering a contraction. The P wave precedes the QRS complex, which represents ventricular depolarization, and the T wave, which represents ventricular repolarization.

The other options are not correct because:

a. Slow repolarization of ventricular Purkinje fibers. This statement is incorrect because it describes the U wave, which is a small and sometimes invisible wave that follows the T wave on the ECG strip. It reflects the repolarization of the ventricular Purkinje fibers, which are specialized cardiac cells that conduct electrical impulses to the ventricles. The U wave is more prominent in conditions that cause hypokalemia, such as diuretic use or vomiting.

c. Early ventricular repolarization. This statement is incorrect because it describes the ST segment, which is the flat line between the QRS complex and the T wave on the ECG strip. It reflects the early phase of ventricular repolarization, which is the process of restoring the electrical charge of the cardiac cells to negative after a contraction. The ST segment can be elevated or depressed in conditions that cause myocardial ischemia or injury, such as angina or myocardial infarction.

d. Ventricular depolarization. This statement is incorrect because it describes the QRS complex, which is the largest and most visible wave on the ECG strip. It reflects the depolarization of the ventricular myocardium, which triggers a ventricular contraction. The QRS complex follows the P wave and precedes the T wave on the ECG strip.