That is a Return on investment issue that both companies face. That is not a product malfuncting like the Taxus system is doing. The nature of the DES business initially is costly for both companies. At least a third of boston stents currently on the shelf expire at the end of May. This short shelf life is a costly part of business that affect both companies bottom line.
Cordis will worry about expiring stents, both company will try to keep it to a minimum. BSX has to worry that this malfunctioning events may or may not continue. IMHO the later is greater.