Cardiac Medicine Certification (CMC) Practice Exam

Which of the following is a potential cause of ventricular tachycardia?

1. Hypertension and hyperglycemia

2. Hypokalemia and myocardial infarction

3. Chronic anxiety and sleep apnea

4. Low calcium and high sodium levels

The correct answer is: Hypokalemia and myocardial infarction

Ventricular tachycardia (VT) is a potentially life-threatening arrhythmia characterized by a fast and abnormal heart rhythm originating from the ventricles. Understanding the causes of VT is essential for managing patients at risk. The presence of hypokalemia — a condition characterized by low potassium levels in the blood — is known to predispose individuals to arrhythmias, including VT. Potassium is crucial for maintaining the electrical stability of cardiac cells, and deficiencies can lead to disturbances in the heart's rhythm. Myocardial infarction, or heart attack, is another significant risk factor for the development of VT. Damage to the heart muscle can disrupt the normal electrical conduction pathways, leading to altered depolarization and increased susceptibility to arrhythmias. The scarred tissue from a myocardial infarction can create areas of re-entry, resulting in VT. While hypertension and hyperglycemia, chronic anxiety and sleep apnea, as well as low calcium and high sodium levels can affect heart health, they are not as directly linked to the acute induction of ventricular tachycardia as hypokalemia and myocardial infarction are. Understanding these associations helps medical professionals monitor and treat patients effectively to prevent serious complications related to arrhythmias.