The goal of this clinical trial is to determine if N-acetylcysteine (NAC) can reduce angina frequency in women with Angina with Non-Obstructive Coronary Arteries (ANOCA). It will also assess the impact of NAC on health status and quality of life. The main questions it aims to answer are:
(i) Does NAC reduce the number of angina episodes per week? (ii) How does NAC affect quality of life and symptom burden in ANOCA patients? (iii) Does NAC reduce the need for short-acting nitrate use?
Researchers will compare NAC to a placebo in a randomized, double-blind, placebo-controlled crossover study to determine its effectiveness.
Participants will receive treatment with NAC 600mg twice daily for 4 weeks (28 days) and matched placebo for 4 weeks (28 days) in a computer-generated random order giving a total dosing period of 8 weeks. There will be a 2-week washout between the two treatment periods.
The effectiveness of N-Acetylcysteine (NAC) will be assessed using the following measures:
Angina Diary: Participants will record the frequency and severity of their angina episodes.
Seattle Angina Questionnaire-7 (SAQ-7): Participants will complete this questionnaire to assess physical limitations, angina frequency, and quality of life.
EuroQol 5-Dimension (EQ-5D) Questionnaire: Participants will rate their overall health and quality of life.
Provision of informed consent prior to any study specific procedures
Female patients aged ≥18 years
No obstructive CAD (defined as either absence of epicardial lesions with ≥50% luminal narrowing in any coronary artery segment on coronary angiography or normal findings on computed tomography (CT) angiogram, indicating the absence of significant stenosis) to account for chest pain symptoms.
Chest pain occurring ≥3 times/week in the preceding two weeks.
Known allergy to NAC or its components.
Acute myocardial infarction admission within the preceding month (hospital admission for prolonged angina paint associated with a cardiac troponin level above the 99th percentile, with a subsequent rise or fall).