The measure could help identify which patients may benefit from intensification of antiplatelet therapy, researchers say.
Measuring preintervention mean platelet volume may be useful for predicting which patients undergoing carotid artery stenting are most likely to develop in-stent restenosis and could therefore benefit from intensification of antiplatelet therapy, according to a study published in the April issue of Stroke.
“Mean platelet volume (MPV) is regarded as an indicator of platelet reactivity,” write the authors, led by Zhengze Dai, MD (Nanjing Pukou Hospital, China). “Larger platelets usually contain more dense granules and pose greater prothrombotic potential. Previous studies have associated elevated MPV with restenosis after coronary angioplasty. But the impacts of MPV on restenosis after CAS have not been studied to date.”
The investigators measured MPV among 261 patients prior to undergoing carotid artery stenting. During a mean follow-up period of 12.1 months, 17.6% of the patients were found to have in-stent restenosis, as evidenced by digital subtraction angiography, CT angiography, or duplex ultrasonography performed at 6 months postprocedure and then annually thereafter.
Multivariate analysis revealed that a baseline MPV >10.1 fL, lesion length, the presence of residual stenosis, and baseline glucose levels were all predictors of in-stent restenosis.
Predictors of In-Stent Restenosis
|
|
OR (95% CI) |
95% CI |
|
MPV > 10.1 fL |
3.20 |
1.28-8.03 |
|
Lesion Length |
1.05 |
1.02-1.08 |
|
Residual Stenosis |
1.07 |
1.05-1.10 |
|
Baseline Serum Glucose |
1.01 |
1.00-1.02 |
The investigators offer three possible explanations as to why MPV may be linked with in-stent restenosis:
1) It may be a marker of platelet size and activity, and greater platelet activity at the injured site may result in greater neointimal hyperplasia.
2) Lesions in the arterial endothelium may activate platelets and recruit leukocytes to the injured site, with platelet-leukocyte interactions leading to an inflammatory response that also aggravates neointimal hyperplasia. The higher the baseline platelet activity, the greater the inflammatory response.
3)Elevated platelet volume may reflect an increase in reticulated platelets or immature platelets, which is an indicator of platelet turnover, and high platelet turnover has been associated with greater platelet aggregation and reduced response to antiplatelet therapy.
They conclude that patients with an elevated MPV prior to undergoing carotid artery stenting may benefit from intensified antiplatelet therapy, but they acknowledge that further studies are first needed to confirm the link. In particular, they point out, it will be important to determine the impact of commonly-used medications, such as antihypertensive, lipid-lowering, and antidiabetic drugs, on MPV measurements.
Source:
Dai Z, Gao J, Li S, et al. Mean platelet volume as a predictor for restenosis after carotid angioplasty and stenting. Stroke. 2018;49:872-876.
Disclosures:
Dai reports no relevant conflicts of interest.
