Cardiovascular Anesthesia — MCQs

Question 51: Which of the following inhalational agents can cause a coronary steal phenomenon?

• A. Isoflurane (Correct Answer)
• B. Sevoflurane
• C. Desflurane
• D. Halothane

Explanation: ***Isoflurane*** - **Isoflurane** is a potent coronary vasodilator, and at higher concentrations, it can preferentially dilate healthy coronary arteries. - This diversion of blood flow away from stenosed or diseased areas of the myocardium can lead to **myocardial ischemia**, known as the **coronary steal phenomenon**. *Sevoflurane* - **Sevoflurane** has minimal effects on coronary autoregulation and is considered to have a lower risk of inducing coronary steal due to its balanced vasodilatory properties. - It is often preferred in patients with **coronary artery disease** due to its favorable cardiac profile. *Desflurane* - **Desflurane** causes some coronary vasodilation but is less prone to causing coronary steal compared to isoflurane. - Its primary cardiovascular effects include a dose-dependent decrease in systemic vascular resistance and an increase in **heart rate**. *Halothane* - **Halothane** is known for its myocardial depressant effects and does not cause significant coronary vasodilation or the coronary steal phenomenon. - It can cause **bradycardia** and **arrhythmias**, particularly in the presence of catecholamines.