Identifying Sex Dimorphism in Peripheral Artery Disease with Platelet Mapping.

BACKGROUND

Clinical outcomes in women with peripheral artery disease (PAD) after revascularization procedures are worse compared to men, yet there is little in the existing literature as why this may be the case. Platelet Mapping is an emerging point-of-care viscoelastic technology that measures the comprehensive properties of a blood clot, including fibrin-platelet interactions. This prospective observational study aimed to characterize the clinical and Platelet Mapping profiles of female and male patients undergoing lower extremity revascularization, and to correlate Platelet Mapping distribution to thrombotic potential.

METHODS

All patients with a diagnosis of PAD undergoing named vessel open or endovascular revascularization to re-establish inflow, outflow, or both, during December 2020 and January 2022 were prospectively included. Patients were followed clinically for thrombosis for up to 1 year. Platelet Mapping assays were performed in 3 clinical phases: preoperative, postoperative inpatient, and postoperative outpatient. Inferential analysis between female and male patient was performed. The quartile distribution of Platelet Mapping metrics associated with thrombosis was used to infer to thrombotic potential.

RESULTS

One hundred seven patients were enrolled, of which 37 (34.6%) were female. Female patients had significantly lower rates of uncontrolled diabetes (2.7% vs. 18.6%), hypertension requiring combination therapy (37.8% vs. 58.6%), chronic kidney disease (27.0% vs. 51.4%), coronary artery disease (29.7% vs. 57.1%), and myocardial infarction (16.2% vs. 35.7%) (all P < 0.05). Platelet reactivity was significantly higher in female patients with greater platelet aggregation (75.9 ± 23.3 vs. 63.5 ± 28.8) and lower platelet inhibition (23.8 ± 23.4 vs. 36.8 ± 28.9) (all P < 0.01). This trend was consistent over time when stratified by the postoperative inpatient and postoperative outpatient clinical phases. There was no statistically discernible difference in the use of antiplatelet therapy between groups, yet female patients continued to exhibit greater platelet reactivity when analyzed by the type of pharmacologic regimen (platelet aggregation on mono-antiplatelet therapy: 80.6 ± 21.0 in women versus 69.4 ± 25.0 in men; platelet aggregation on dual antiplatelet therapy: 67.9 ± 23.8 in women versus 44.8 ± 31.8 in men) (all P < 0.01). Twenty-one patients experienced postoperative graft/stent thrombosis within the study period. In relation to the overall study population, patients with thrombosis had Platelet Mapping metrics above the 50th percentile of overall platelet aggregation distribution.

CONCLUSIONS

There is a growing appreciation for the differences in etiology, disease progression, and outcomes of cardiovascular conditions as they relate to sex. In this cohort, traditional cardiovascular risk factors were in lower prevalence in female patients. Platelet reactivity was found to be higher across clinical phases and antiplatelet regimens. High platelet reactivity was also associated with an increased incidence of thrombosis after lower extremity revascularization. These hypothesis-generating findings provide the basis for further exploration of sex-specific coagulation profiling in PAD patients.