CapHTen
Research type
Research Study
Full title
Capillaroscopy in Hypertension & Heart Failure
IRAS ID
111953
Contact name
Tarek Francis Antonios
Contact email
Sponsor organisation
St George's University of London
Duration of Study in the UK
0 years, 6 months, 7 days
Research summary
The cause of high blood pressure or hypertension is still unknown despite the fact that it is a major risk factor for cardiovascular disease (CVD) affecting 1 in 3 individuals in the UK. Increasing evidence suggests a key role for the small blood vessels (or microcirculation) in the causation of hypertension. A reduction in the density (i.e. rarefaction) of small blood vessels called capillaries is a consistent finding in hypertension. We have previously shown that much of the capillary rarefaction in hypertension is due to the structural (i.e. anatomic) absence of capillaries. We have also shown significant capillary rarefaction in patients with borderline intermittent hypertension as well as in normotensive adult and newborn offspring of hypertensive parents supporting our premise that capillary rarefaction is a primary structural abnormality that antedates the onset of the rise in blood pressure and therefore could be involved in the causation of hypertension.
There is increasing evidence that capillary rarefaction occurs also in patients with heart failure. In patients with dilated hearts (cardiomyopathy) and heart failure, analysis of heart tissue biopsy specimens revealed marked capillary rarefaction associated with a reduced coronary blood flow. More recently in an autopsy study, patients with heart failure and preserved ejection fraction (HFpEF) have been found to have significantly more coronary capillary rarefaction, causing myocardial fibrosis, than controls supporting a role of coronary capillary rarefaction in the pathophysiology of HFpEF. Intriguingly HFpEF patients were also found to have significant ≈50% capillary rarefaction in their thigh skeletal muscle, which was significantly correlated with their severe exercise intolerance in comparison with controls.
The results of this pilot study will be used to estimate the number of patients needed to perform a larger study and be the basis of a larger British Heart Foundation grant application, which will include patient & public involvement.REC name
London - Brent Research Ethics Committee
REC reference
17/LO/1364
Date of REC Opinion
29 Sep 2017
REC opinion
Further Information Favourable Opinion