In the presence of coronary artery disease (CAD), which condition has a high risk for sudden cardiac death?

In the presence of coronary artery disease (CAD), which condition has a high risk for sudden cardiac death?

• A. Bradycardia
• B. QT elongation
• C. Atrial fibrillation
• D. Stenosis

Answer: (B)

QT elongation is a significant predictor of sudden cardiac death, particularly in patients with underlying coronary artery disease (CAD). This prolonged interval reflects disturbances in the heart's electrical repolarization process, which can lead to life-threatening arrhythmias such as Torsades de Pointes. In the context of CAD, where the heart may already be compromised, the risk of arrhythmias increases substantially. Studies have shown that patients with prolonged QT intervals are at a higher risk of experiencing sudden cardiac events, especially when other risk factors, such as ischemia and structural heart changes from CAD, are present. In contrast, while bradycardia, atrial fibrillation, and stenosis can be concerning in patients with CAD, they do not carry as high a risk for sudden cardiac death as QT elongation does. Bradycardia may lead to decreased cardiac output but is not inherently associated with increased arrhythmogenic risk in the same way. Atrial fibrillation can cause significant morbidity and increase stroke risk, but it does not have the same direct correlation to sudden cardiac death as prolonged QT does. Similarly, stenosis itself refers to the narrowing of arteries, and while significant stenosis can lead to ischemia, it is the resultant electrical disturbances that are

QT elongation is a significant predictor of sudden cardiac death, particularly in patients with underlying coronary artery disease (CAD). This prolonged interval reflects disturbances in the heart's electrical repolarization process, which can lead to life-threatening arrhythmias such as Torsades de Pointes. In the context of CAD, where the heart may already be compromised, the risk of arrhythmias increases substantially. Studies have shown that patients with prolonged QT intervals are at a higher risk of experiencing sudden cardiac events, especially when other risk factors, such as ischemia and structural heart changes from CAD, are present.

In contrast, while bradycardia, atrial fibrillation, and stenosis can be concerning in patients with CAD, they do not carry as high a risk for sudden cardiac death as QT elongation does. Bradycardia may lead to decreased cardiac output but is not inherently associated with increased arrhythmogenic risk in the same way. Atrial fibrillation can cause significant morbidity and increase stroke risk, but it does not have the same direct correlation to sudden cardiac death as prolonged QT does. Similarly, stenosis itself refers to the narrowing of arteries, and while significant stenosis can lead to ischemia, it is the resultant electrical disturbances that are