A 68-year-old woman presents 2 days after undergoing emergency coronary angiography with placement of 3 stents in the left anterior descending artery for an acute myocardial infarction. Medical history is significant for hypertension, hypercholesterolemia, and coronary artery disease. Her home medications include metoprolol, enalapril, atorvastatin, and aspirin. Her temperature is 37.3°C (99.1°F), pulse is 93/min, and blood pressure is 115/78 mm Hg. Physical examination reveals bluish discoloration of the toes on both feet, as shown in the photograph. The affected areas are cool and tender to palpation, whereas the surrounding skin of the feet is warm. Femoral and pedal pulses are palpable bilaterally. This patient is at increased risk for which of the following conditions?