Effect of hemorheological parameters on myocardial injury after primary or elective percutaneous coronary intervention

Background Abnormal blood viscosity favors atherosclerosis owing to endothelial dysfunction and changes in shear stress. Its effect on coronary microvasculature during percutaneous coronary intervention (PCI) is still unknown. We aimed to investigate the role of hemorheological parameters in the incidence of microvascular obstruction (MVO) and the periprocedural necrosis after primary or elective PCI, and secondarily, we evaluated their prognostic significance. Materials and methods We enrolled 25 patients with ST-elevation myocardial infarction (STEMI), 30 patients with non-ST-elevation myocardial infarction (NSTEMI), and 30 patients with stable angina (SA) undergoing PCI. MVO in patients with STEMI and periprocedural necrosis in patients with NSTEMI and those with SA were assessed using angiographic/electrocardiographic and laboratory methods, respectively. Hemorheological profile included blood viscosity (η) at shear rates 200 s -1 and 1 s -1, the erythrocyte aggregation index (η 1 /η 200), and plasma viscosity. Major adverse cardiovascular events occurrence was evaluated at follow-up. Results Patients with STEMI experiencing angiographic MVO (28%) had higher η 200 (5.42±1.28 vs. 3.98±1.22 mPas; P=0.015). Similarly, patients with STEMI experiencing electrocardiographic MVO (56%) had higher η 200 (4.58±0.36 vs. 3.94±0.19 mPas; P<0.001). Among patients with SA and patients with NSTEMI, those experiencing periprocedural necrosis (23.3%) had higher η 200 (5.30±0.86 vs. 4.37±0.88 mPas; P=0.001), η 1 (19.52±9.62 vs. 13.29±7.65 mPas; P=0.015) and η 1 /η 200 values (3.64±1.50 vs. 2.72±0.92; P=0.007). These significant differences were maintained after adjustment for age, sex, and cardiovascular risk factors. At follow-up (30±6 months), 25 (29.4%) patients presented major adverse cardiovascular events, and they had higher η 200 (5.18±1.00 vs. 4.25±1.01 mPas; P<0.001). Conclusion In patients undergoing either urgent or elective PCI, hemorheological parameters might contribute to myocardial injury and, if furtherly confirmed, to an unfavorable outcome.