Cholesterol crystals rupture biological membranes and human plaques during acute cardiovascular events-a novel insight into plaque rupture by scanning electron microscopy

Plaque rupture and/or erosion are considered the leading cause of cardiovascular events. To elucidate this process, we demonstrated that during cholesterol crystallization the occupied volume increases rapidly and sharp–tipped crystals cut through thin biological membranes in their path. The amount of cholesterol correlated directly with both peak level and rate of crystal growth (r = 0.98; r = 0.99; p < 0.01, respectively). These observations suggest that crystallization of cholesterol in atherosclerotic plaques can induce cap rupture and/or erosion. Observations by scanning electron microscopy confirmed similar findings of cholesterol crystals perforating the lumen surface in human coronary artery segments with ruptured plaque.