A 55-year-old woman with a mechanical mitral valve (on warfarin, INR 2.8) and recent diagnosis of acute coronary syndrome (non-STEMI) presents for coronary angiography. Angiography reveals a critical left anterior descending (LAD) stenosis requiring stent placement. She has no contraindications to dual antiplatelet therapy. Which of the following is the most appropriate antiplatelet loading strategy before PCI?