Clinical Research Directory

WISE CVD - Continuation (WISE HFpEF)

The Women's Ischemia Study Evaluation (WISE), a cohort study of over 1000 women, has made many contributions to the understanding of cardiovascular disease. A milestone acknowledged in the 2011 AHA Herrick Lecture is the role of Coronary Microvascular Dysfunction (CMD) in women with symptoms/signs of ischemia without obstructive coronary artery disease (CAD). While in 1996, CMD was considered "an imaging artifact", in 2013, it is a widely accepted as a pathophysiologic process requiring systematic cohesive scientific pursuit. CMD is prevalent, associated with adverse clinical outcomes, poor quality of life and healthcare costs rivaling obstructive CAD. There are 2-3 million US women with CMD, and 100,000 new cases projected annually placing CMD prevalence, morbidity and costs higher than all female reproductive cancers combined. Among women with ischemia, preserved ejection fraction and no obstructive CAD, it has been observed that there are relatively more new onset heart failure (HF) hospitalizations than nonfatal myocardial infarction (MI). It has been hypothesized that CMD contributes to left ventricular (LV) diastolic dysfunction and subsequent heart failure with preserved ejection fraction (HFpEF). Preliminary data further suggests that left ventricular diastolic dysfunction is linked to CMD via a mechanism of augmentation and/or perpetuation by cardiomyocyte fat accumulation. HFpEF is prevalent in women and older men, but poorly understood. Mechanistic understanding is critical to HFpEF intervention and guideline development. The study hypotheses are as follows: 1. Risk factor conditions (hypertension, dyslipidemia, dysglycemia, loss of estrogen) promote an inflammatory and pro-oxidative state making the microvasculature vulnerable; 2. Vulnerable coronary microvasculature becomes dysregulated (sympathetic nervous system activation, endothelial dysfunction, changes in vascular smooth muscle activation, spasm) causing repeated episodes of transient ischemia; 3. Repeated ischemia-reperfusion episodes facilitate preconditioning with preservation of cardiomyocyte contractile and microvascular function against ischemic injury; 4. Ischemia-reperfusion and preconditioning lead to cardiomyocyte fat accumulation and relaxation impairment resulting in diastolic dysfunction and heart failure with preserved ejection fraction (HFpEF).

Microvascular Coronary Rehabilitation For Improving Treatment - Feasibility Study

The goal of this clinical trial is to assess the feasibility of undertaking a randomized controlled trial assessing the impact of a personalised, intense cardiac rehabilitation programme involving high intensity interval exercise (HIIT) and dietary advice (termed MICROFIT) on symptom burden in patients with microvascular coronary dysfunction. The main questions it aims to answer are: 1. Feasibility of undertaking randomised controlled trial of MICROFIT in patients with coronary microvascular dysfunction (recruitment rates, retention and adherence, acceptability of MICROFIT and participants' and practitioners' experiences of trial participation) 2. Preliminary data on the effect that MICROFIT has on angina symptoms in patients with microvascular coronary dysfunction, as measured by Seattle Angina Questionnaire 3. Preliminary data on the fidelity and clinical efficacy of MICROFIT Participants will be randomized to either MICROFIT + Usual Care, or Usual Care group. Participants in both arms of the trial will: * Undergo a series of investigations, including cardiopulmonary exercise test (CPET), dual xray absorptiometry (DEXA), echocardiogram, cardiac MRI scan, blood tests, at the start of the trial and again after 6 months * Measure their living activity by using an activity tracker (GeneActiv) as well as a photographic diet diary for a week at the start of the trial and again after 6 months * Complete a series of questionnaires to assess angina symptom burden, mental health and quality of life, at the start of the trial and again after 6 months. Participants in the intervention arm of the study will: 1. Undergo MICROFIT intervention. MICROFIT includes a combination of exercise and diet management sessions over 24 weeks. It involves: * 1:1 high-intensity interval training ('HIIT') sessions with a personal trainer and guidance on exercise sessions to be performed at home * 1:1 sessions with a dietician to support them with improvements in diet. 2. Visit clinic on two additional occassions during the trial to discuss their progress with a cardiologist 3. Undergo an interview at the end of the study to discuss their experiences of participation in the study 4. Receive a debrief on their investigation results and progress made at the end of their study Participants in the Usual Care arm of the study will: 1. Receive standard Usual Care advice regarding lifestyle changes and targeted medical therapy offered to patients with coronary microvascular dysfunction. 2. Receive a debrief on their investigation results and progress made at the end of their study 3. Undergo a 'taster' session with the personal trainer to discover what the intervention involves.

Development of a Novel Stress Testing Protocol to Define the Relationship Between Coronary Microvascular Dysfunction and Diastology in Women With Angina But No Evidence of Obstructive Coronary Artery Disease

Microvascular coronary dysfunction (MCD) (abnormities in small blood vessels/arteries in heart) with symptoms of persistent chest pain, primarily impacts women. There are an estimated 2-3 million women in the US with MCD and about 100,000 new cases annually. Recent data from our research group suggests that coronary microvascular disease impairs the way the heart relaxes. This pilot study will attempt to exacerbate this phenotype in an effort to better understand the pathophysiology of the disease. The investigators will recruit 30 volunteers total (10 healthy calibration subjects, 10 women with microvascular disease, and 10 age-match women for the group with microvascular disease). Subjects will undergo a series of "stress" maneuvers in conjunction with advanced cardiac magnetic resonance imaging.