Which inhaled anesthetic is considered most cardioprotective?

• A. Sevoflurane
• B. Desflurane
• C. Nitrous oxide
• D. Isoflurane

Answer: (D)

Inhaled volatile anesthetics can protect the heart by triggering pharmacologic preconditioning, a process where brief exposure to the agent activates cellular pathways that make the myocardium more resistant to ischemia-reperfusion injury. Among the common inhaled agents, isoflurane shows the strongest cardioprotective effect. It robustly engages the protective signaling that reduces infarct size and helps preserve myocardial function during periods of reduced blood flow. Mechanistically, this protection involves pathways like mitochondrial potassium ATP channels and downstream effects that limit calcium overload and cellular stress, while still supporting coronary flow and lowering myocardial oxygen demand.

Nitrous oxide doesn’t provide meaningful preconditioning, so it offers little cardioprotection. Sevoflurane and desflurane do confer some protective effects, but the magnitude and consistency of protection are greatest with isoflurane, making it the preferred option when aiming for cardioprotection during anesthesia.