Magnesium has been investigated for its role in supporting or treating chest pain, particularly in the context of acute myocardial infarction (heart attack) and angina. Several clinical studies have evaluated intravenous magnesium sulfate in patients with acute coronary syndromes. Magnesium is known to have physiological effects such as vasodilation, antiarrhythmic properties, and the ability to inhibit calcium influx into cardiac cells, which could theoretically reduce myocardial oxygen demand and improve blood flow.

Early studies from the 1990s, such as the Second Leicester Intravenous Magnesium Intervention Trial (LIMIT-2), reported a reduction in mortality with magnesium administration after heart attack. However, larger randomized controlled trials, including the ISIS-4 and MAGIC trials, failed to confirm these benefits, showing no significant reduction in mortality or improvement in clinical outcomes. As a result, routine use of intravenous magnesium for acute chest pain (outside of specific indications such as torsades de pointes or documented hypomagnesemia) is not recommended in current clinical guidelines.

Oral magnesium supplementation has also been studied for chronic stable angina, with some small studies suggesting modest improvements in exercise tolerance, but the evidence is limited and not conclusive. Overall, while there is a scientific rationale and some clinical evidence for magnesium’s use in chest pain related to cardiac events, the overall quality and consistency of the evidence are moderate, justifying a rating of 3 out of 5.