ACE and diabetes mellitus: ,92 Whether CCS patients with type 4a MI, who are not already on angiotensin-converting enzyme (ACE) inhibitors (for heart failure, hypertension, or diabetes) or beta-blockers (for left ventricular dysfunction or systolic heart failure), would benefit from the addition of these pharmacotherapies to reduce the risk of future MACE is not known, and needs to be evaluated in future studies.