This clinical trial is focused on studying the effects of a medication called diltiazem hydrochloride on a condition known as coronary microvascular dysfunction, which is a type of heart problem that affects the small blood vessels in the heart. People with this condition often experience chest pain, known as angina, even though their larger heart arteries are not blocked. The trial aims to see if diltiazem can improve the function of these small blood vessels and help reduce symptoms in patients who have been experiencing angina regularly despite other treatments.
Participants in the study will be given either diltiazem or a placebo, which is a substance with no active medication. The study will last for a period of up to six months. During this time, the effects of diltiazem on the heart’s small blood vessels will be closely monitored. The goal is to determine if diltiazem can help normalize the function of these vessels without causing any of the normal parameters to become abnormal.
The study will assess the success of the treatment by checking if at least one of the abnormal heart function parameters returns to normal. These parameters include measures like the Index of Microcirculatory Resistance (IMR) and the Coronary Flow Reserve (CFR). A successful treatment would mean that patients experience fewer symptoms of angina and improved heart function. The trial is expected to continue until 2026, providing valuable insights into the potential benefits of diltiazem for patients with coronary microvascular dysfunction.



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