Polyester implantable medical device with controlled in vivo biodegradability

A stent, comprising:

• a blend of a high molecular weight polyester and a low molecular weight polyester, wherein
• the high molecular weight polyester has a molecular weight of about 200,000 Da to about 1,000,000 Da;
• the low molecular weight polyester has a molecular weight of about 200 Da to about 20,000 Da;
• the low molecular weight polyester comprises about 0.1% w/w to about 5% w/w of the blend;
• and,
• at least a portion of the low molecular weight polyester is substituted with an acidic moiety.