Ticagrelor Shows Benefits in Coronary Microvascular Function after NSTEMI

Coronary microvascular disfunction (CMD) is an important long-term prognosis predictor. CMD treatment can be an effective therapeutic strategy for patients with acute coronary syndrome (ACS). Nevertheless, more studies are needed to assess different strategies.

El ticagrelor muestra beneficios en la función microvascular coronaria luego de un IAMSEST

In the PLATO (Study of Platelet Inhibition and Patient Outcomes) study, ticagrelor vs. clopidogrel reduced ischemic events and overall mortality in patients with ACS. It was posited that ticagrelor may have a beneficial effect on microcirculation.

Several studies have evaluated microvascular injury reduction using ticagrelor in patients who underwent coronary angioplasty due to ST-segment elevation acute coronary syndromes (STEACS). However, there were no studies with patients with STEACS.

This open-label, randomized, prospective study compared ticagrelor vs. clopidogrel in coronary microvascular function before and after coronary angioplasty in patients with STEACS.

The study enrolled 118 patients, 60 in the ticagrelor group vs. 58 in the clopidogrel group. Mean patient age was 59 years old, 84% of patients were male, and 23% had diabetes. The most frequently affected artery by the infarction was the anterior descending artery, followed by the right coronary artery.

The primary endpoint (PEP) was the microvascular resistance index (MRI) in the infarction-related artery between both groups. The secondary endpoint (SEP) was the assessment of other parameters of coronary microcirculation (CFR, RRR, and FFR); differences among these parameters between the infarction-related artery and the non-culprit artery were also included.

As regards baseline coronary physiological measurements, the MRI was significantly lower for the ticagrelor group vs. the clopidogrel group in the infarction-related artery (p = 0.022). In turn, RRR was higher in the ticagrelor group compared with the other group (p = 0.012). There were no differences in CFR measurements between both groups. The same was observed when baseline measurements in the non-infarction-related artery were analyzed.

After angioplasty, the MRI was significantly lower in the ticagrelor group (p = 0.02), and the post-angioplasty RRR was higher in the ticagrelor group (p = 0.04). In the ticagrelor group, the post-angioplasty MRI was lower than before the procedure (p = 0.019), whereas there clopidogrel group showed no such difference.

Conclusion

In patients with STEACS, ticagrelor significantly improved microvascular function before and after coronary angioplasty compared with clopidogrel. There was a larger effect on the infarction-related artery.