Olive extract enriched with hydroxytyrosol improves cardiac and vascular function in patients with stable coronary artery disease: a double-blind, placebo-controlled trial

Abstract

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Olive Heart Operational Programme Competitiveness, Entrepreneurship and Innovation 2014–2020 (EPAnEK) Aims We investigated the effect of olive extract enriched with hydroxytyrosol, on vascular and myocardial function markers in patients with stable coronary artery disease (SCAD). Methods In a prospective, cross-over, double-blind, placebo-controlled, clinical trial, 30 patients with stable CAD were randomly assigned to an oral supplement containing olive oil extract enriched with hydroxytyrosol (OOHT) or placebo for one month and then were crossed over to the alternate treatment (placebo or OOHT for one more month). We measured a) perfused boundary region (PBR) of the sublingual arterial microvessels (increased PBR indicates reduced endothelial glycocalyx thickness), b) flow-mediated dilation (FMD), c) Coronary Flow Reserve (CFR) and markers of LV diastolic function by Doppler echocardiography d) Pulse Wave Velocity (PWV) e) oxidative/nitrosative stress and inflammatory biomarkers and blood lipids at baseline and after one month treatment. Results Treatment with OOHT improved PBR, FMD, CFR and PWV compared to baseline (1.81±0.35 vs 1.77±0.40 μm p = 0.04 3.71±2.12 vs 6.51±2.31%, p<0.001;2.37±0.40 vs 2.45±0.41, p = 0.030 and 11.03±1.81 vs 11.78±2.34 m/sec, p = 0.002), while there was no effect after placebo (p>0.05). Compared to baseline, treatment with OOHT reduced malondialdehyde (MDA) a marker of lipid peroxidation (2.10±1.37 vs 1.69±0.83 mmol/lt, p = 0.045), oxidized LDL, triglycerides, PCSK9 and CRP blood levels (p<0.05) in contrast to placebo. There was a parallel improvement of E’ of the mitral annulus and deceleration time of the E wave of mitral inflow after OOHT (p<0.05) but not after placebo. Conclusions Olive extract enriched with hydroxytyrosol improves endothelial and arterial function likely by reducing oxidative and inflammatory burden leading to improved LV diastolic function after one month of treatment in patients with stable CAD.