Which medication is known to prolong exercise duration and increase time to angina?

Ranolazine is specifically designed to address chronic angina and has a unique mechanism of action that improves myocardial energy metabolism. It helps to enhance exercise performance by reducing the occurrence of angina during physical activity, which allows for a longer duration of exercise without discomfort. This effect is particularly beneficial for patients with stable angina, as it aids in increasing exercise tolerance and prolongs the time until angina occurs.

In contrast, metoprolol, a beta-blocker, primarily works by reducing heart rate and myocardial oxygen demand, which can also manage angina but does not directly extend the duration of exercise in the same way ranolazine does. Aspirin is mainly an antiplatelet agent that helps prevent cardiovascular events rather than specifically affecting exercise duration or angina. Amlodipine, a calcium channel blocker, can help with angina by promoting vasodilation and improving blood flow, but its primary role isn't to prolong exercise duration to the same extent as ranolazine.

Thus, ranolazine stands out for its specific action in prolonging exercise duration and delaying the onset of angina symptoms.