Clinical trials

Patients with heart attack or heart injury are tested (angiogram) for blockages in their arteries. Patients may develop heart problems caused by damage to small (microvascular) blood vessels. Eplerenone, a mineralocorticoid receptor-selective antagonist, reduces blood vessel injury and is used to treat high blood pressure and heart failure. Aim: to test the use of eplerenone in patients with heart attack/heart injury an no obstructive coronary arteries and small vessel problems (coronary microvascular dysfunction). Patients admitted to hospitals in the West of Scotland (2.5 million) and referred for invasive management to the Golden Jubilee and Hairmyres hospitals because of a suspected heart attack heart will be invited to participate into a registry-based clinical trial. Screening, enrolment and verbal, informed consent will be obtained during the angiogram then written consent on the ward. Small vessel disease will be assessed using a 'diagnostic' guidewire during the standard angiogram. People with small vessel problems will be invited to participate in a clinical trial of usual care or eplerenone. Coronary microvascular dysfunction is defined as an index of microvascular resistance ≥25. Coronary flow reserve (CFR abnormal \<2.0), microvascular resistance reserve ratio (MRR, abnormal \<2.5), and resistance reserve ratio (RRR abnormal \<2.0), measured simultaneously with IMR, are predefined parameters of interest. Patients will be allocated into one of the 3 groups: * Group 1: Patients without coronary microvascular dysfunction. No eplerenone * Group 2: Patient with coronary microvascular dysfunction. Usual care, no eplerenone. * Group 3: Small vessels abnormal. Eplerenone tablets. The primary outcome for the trial will be reduced heart injury (biomarkers) in patients with microvascular disease. We will also test heart function (MRI scan) at enrolment and at six months. All patients (Groups 1, 2 and 3) will have an angiogram. Standard blood tests will be collected during the hospital stay, and then again at 1 and 6 months. Other outcomes include questionnaires (health status). We will gather information on longer-term health outcomes (hospitalisation, death) using confidential electronic record linkage. We will ask for permission to store blood samples for future research. The research will improve scientific knowledge about eplerenone therapy in this patient group. The study will create a repository of clinical samples and images which will provide vital data for studies of endotypes of myocardial infarction or injury with no obstructive coronary arteries.

'Heart attack', known as acute ST-segment elevation myocardial infarction, is a leading cause of heart failure and death. A lack of blood and oxygen damages the heart muscle potentially causing heart failure and premature death. During the past 25 years, despite intensive research efforts, few, if any new medicines have been shown to prevent heart failure after a heart attack. New treatment approaches are needed. The standard treatment for a heart attack is for a doctor to reopen the blocked blood vessel. The treatment is called primary percutaneous coronary intervention, or 'primary PCI'. The doctor places a thin plastic tube in a blood vessel in the wrist. The doctor then passes a longer thin tube via the wrist into the blocked heart artery. A small balloon is then used to open the blockage and a thin metal tube (stent) is placed inside the blood vessel to keep it open. The patient then returns to the ward. Supersaturated oxygen therapy is designed to increase the blood oxygen level after the stent has been placed. The treatment lasts for one hour. The treatment is approved (CE-mark, FDA-approved) for patients presenting to doctors within 6 hours of symptoms onset. Supersaturated oxygen therapy is supported by results from two prior studies (AMIHOT, AMIHOT-II). Previously, the approach involved passing the plastic tubes via the femoral artery in the groin, limiting adoption. Since using the wrist is now standard care approach for heart attack treatment, our idea is to give supersaturated oxygen therapy via the wrist rather than the groin. In this research study, we aim to assess the feasibility, safety and potential benefits of increasing blood oxygen content in patients who have been treated for a heart attack. The novel aspects of the study including giving the therapy via the wrist, the dummy procedure (sham/placebo), the randomized treatment assignment (coin-flip, play of chance), and the masking (blinding) of the patient participating in the study and the attending clinical staff, investigators and outcome assessors. Patients who have been successfully treated for a heart attack will be invited to give informed consent at the end of the procedure. Fifty-six patients who have experienced a heart attack affecting the main area of the heart (anterior wall) will receive supersaturated therapy, or a dummy procedure, for one hour. The dummy procedure involves local anesthetic in the wrist and a pressure band as would normally be done. The study also involves measuring small vessel function before and after the supersaturated oxygen / dummy procedure, a heart MRI scan at 2-5 days and again 3 months later, health questionnaires and blood samples to assess heart injury and to be stored for future research. The study will provide information on safety, feasibility and preliminary insights into potential benefits to patients. The study will clarify whether a much larger study is warranted.