Ticagrelor improves microvascular endothelial functioning, has no impact on arterial stiffness

Adult patients with coronary artery disease and abnormal endothelial functioning who were given ticagrelor showed improvements in their endothelial functioning, according to a new study.

Researchers—led by Shahar Lavi, MD, with the division of cardiology at Western University in London, Ontario, Canada—performed an open-label clinical trial with 45 adult participants. The team’s results were published online July 26 in JAMA Cardiology.

To qualify for inclusion, the patients had to have coronary artery disease, with at least two cardiovascular risk factors such as diabetes or hypertension, and abnormal endothelial function, defined as a reactive hyperemia index (RHI) of less than 2.0.

Over the short term, the researchers found, RHI in these patients (41 men and four women above the age of 18 with a mean age of 64 years) improved with the use of ticagrelor. The investigators assessed endothelial functioning before and after giving a dose of the drug, with assessments scheduled at the drug’s peak and trough levels. When ticagrelor levels were highest, patients showed significantly improved endothelial functioning compared with measurements taken at baseline and when the drug was at its lowest levels. 

In a negative finding, they found that the use of ticagrelor did not improve measures of arterial stiffness. “Considering the twice-daily drug administration, endothelial functioning may be improved during the dosing cycle of Ticagrelor,” wrote Lavi et al.

They pointed out, though, that the beneficial effect is not sustained throughout the 12 hours between drug dosing times. It is maintained only when patients continue taking the drug.

The team also noted the contrast between their findings in older patients with coronary artery disease and the lack of impact of ticagrelor on reactive hyperemia in healthy young people. The researchers speculated that the potential benefits of this drug may only be seen in patients who have established cardiovascular disease and endothelial dysfunction.