Ginkgo biloba Extract Improves Coronary Blood Flow in Patients with Coronary Artery Disease: Role of Endothelium-Dependent Vasodilation

Abstract

Ginkgo biloba extract (GBE) has well-documented cardioprotective effects on coronary flow and positive effects on vasodilation through endothelium-derived nitric oxide in experimental animals, but these impacts in patients with coronary artery disease (CAD) have not yet been investigated. We designed this study to test the effects of GBE on distal left anterior descending coronary artery (LAD) blood flow and endothelium-dependent brachial artery flow-mediated dilation (FMD) in patients with CAD. Eighty CAD patients were randomly assigned to either GBE or saline (control) groups. LAD blood flow and brachial artery FMD were measured non-invasively using high-resolution ultrasound before and after intravenous administration of GBE or saline. GBE significantly increased LAD blood flow in maximal diastolic peak velocity (MDPV), maximal systolic peak velocity (MSPV) and diastolic time velocity integral (DTVI) compared with the control group (16.14 ± 10.93 % vs. 0.28 ± 2.14 %, 9.14 ± 8.23 % vs. 0.79 ± 2.56 %, and 15.23 ± 7.28 % vs. 0.42 ± 2.43 %, respectively, p < 0.01). Brachial artery FMD was also increased by 69.75 % (from 3.95 ± 1.49 % to 6.55 ± 2.51 %, p < 0.01). A linear correlation was found between the percentage changes in MDPV, MSPV, or DTVI of LAD blood flow and the percentage change in brachial artery FMD following treatment with GBE (r = 0.612, 0.486, or 0.521, respectively, p < 0.01). In summary, our data demonstrate that GBE treatment in CAD patients leads to an increase of LAD blood flow in MDPV, MSPV and DTVI, and the increase response might relate to the improved endothelium-dependent vasodilatory capacity.

Abbreviations

CAD: coronary artery disease

DTVI: diastolic time velocity integral

FMD: flow-mediated dilation

GBE: Ginkgo biloba extract

LAD: distal left anterior descending coronary artery

MDPV: maximal diastolic peak velocity

MSPV: maximal systolic peak velocity

NO: nitric oxide

TTDE: transthoracic Doppler echocardiography

Ginkgo biloba - Ginkgoaceae - coronary artery disease - endothelial function - flow-mediated dilation - transthoracic Doppler echocardiography

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