Baseline von Willebrand factor plasma levels and no-reflow phenomenon after primary percutaneous coronary intervention for ST segment elevation myocardial infarction.

No-reflow phenomenon is associated with a poor prognosis and its underlying mechanisms are still poorly understood. von Willebrand Factor (vWF) is a central molecule in haemostasis which plays an important role in acute coronary syndromes. However its possible role in no-reflow has not been assessed prior to this study. Quantitative baseline vWF plasma antigen was measured by immunoturbidometric assay in 54 consecutive patients with a first ST segment elevation acute myocardial infarction, treated by primary percutaneous coronary intervention within 12 h of symptom onset. Definitions of no-reflow were (1) angiographic: final TIMI flow ≤2 or final TIMI flow 3 with a myocardial blush grade <2; (2) electrocardiographic: lack of ST segment resolution (≤50% reduction of ST segment elevation at 90 min). Angiographic and electrocardiographic no-reflow was observed in 32 (59%) and 30 (56%) patients, respectively (only 9 patients had both type of no-reflow). Plasma levels of vWF were significantly higher in patients with angiographic no-reflow but not in those with electrocardiographic no-reflow. Also, vWF was the most powerful independent predictors of angiographic no-reflow (OR 3.8, 95% CI 1.1-12.9, p=0.033). Our results provide new insights into no-reflow pathophysiology with appealing therapeutic implications.