The interplay between thrombosis and inflammation, known as thromboinflammation, is a significant pathway driving cardiovascular and autoimmune diseases, as well as COVID-19. Key modulators of this process have emerged as innate immune cells. Strategically positioned to promote thromboinflammation are neutrophils, the most predominant white blood cells in humans. Neutrophils can trigger an organized cell death pathway by releasing decondensed chromatin structures known as neutrophil extracellular traps. These structures are decorated with histones, cytoplasmic, and granular proteins, and have cytotoxic, immunogenic, and prothrombotic effects, which can accelerate disease progression. The activities of PAD4, which catalyses the citrullination of histones, and the neutrophil inflammasome are required for distinct steps leading to extracellular DNA release (NETosis). PAD4 activity has important implications for understanding the processes that drive thromboinflammation by linking the immunological function of neutrophils with the procoagulant and proinflammatory activities of monocytes and platelets. We will discuss how vascular blockages in thromboinflammation occur due to the interaction between neutrophil extracellular traps and ultra-large VWF (von Willebrand Factor). PAD4 activity has important implications for understanding the processes that drive thromboinflammation by linking the immunological function of neutrophils with the procoagulant and proinflammatory activities of monocytes and platelets. It will also review the mechanisms whereby vaso-occlusive events in thrombo-inflammation depend on the interaction of neutrophil extracellular traps with von Willebrand factor and suggest the importance of PAD4 in neutrophil inflammasome assembly and neutrophil extracellular traps in thrombo-inflammatory diseases such as atherosclerosis and CVD.