List of products in the National Drug Code with proprietary name . This medication is used in combination with "blood thinners" such as warfarin to keep clots from forming after heart valve replacements. Clots are a serious complication that can cause strokes, heart attacks, or blocked blood vessels in the lungs (pulmonary embolisms). Dipyridamole is an antiplatelet drug. It helps to keep blood flowing by stopping platelets from clumping together and by keeping heart blood vessels open.