A patient taking nitroglycerin and still experiencing chest pain should be suspected of having?

When a patient is taking nitroglycerin, which is a medication commonly used to relieve chest pain associated with angina, and still experiences chest pain, it is a strong indicator that ongoing cardiac ischemia may be present. Nitroglycerin works by dilating blood vessels, improving blood flow to the heart muscle, and alleviating ischemic pain. If the chest pain persists despite the administration of nitroglycerin, it suggests that the heart is not receiving adequate oxygen or nutrients due to narrowed or blocked coronary arteries, indicating ongoing ischemia.

This situation may also signal the potential for more serious conditions like an unstable angina or a myocardial infarction (heart attack), where urgent medical attention is required to prevent further damage to the heart muscle. The other potential reasons, such as elevated blood pressure or non-cardiac related pain, would not typically lead to persistent pain that nitroglycerin fails to alleviate. While expired medication could also be a concern, it is less common, and if the nitroglycerin was properly stored and used within its shelf life, it is not as likely to be the immediate issue in the context of ongoing cardiac symptoms.