Should all patients be given renin-angiotensin system blockers after cardiac bypass surgery?

This study looked at the use of renin-angiotensin system (RAS) inhibitors after coronary artery bypass surgery (CABG). The study showed that RAS inhibitors are beneficial for all patients after CABG and reduce the risk of heart attack, stroke, or death.

CABG redirects blood around a section of a blocked or partially blocked artery in the heart. It involves taking a healthy blood vessel from the leg, arm, or chest and connecting it to redirect blood blow to the heart. RAS inhibitors are a family of blood pressure medications that include angiotensin-converting enzyme inhibitors (ACE inhibitors) and angiotensin receptor blockers (ARBs). RAS inhibitors are recommended for patients who undergo CABG surgery and have risk factors for further heart problems. These risk factors include diabetes, heart failure, high blood pressure, or a history of a previous heart attack. 

It is not known if RAS inhibitors are also beneficial for patients who have had a CABG and do not have any of these risk factors.

This study reviewed the records of 28,782 patients who underwent CABG. RAS inhibitors were prescribed to 77% of patients who had risk factors for further heart disease. RAS inhibitors were also prescribed to 29.7% of patients who did not have these risk factors. The risks of major adverse cardiac events (MACE) such as stroke, heart attack, or death were evaluated. 

In all patients, the risk of MACE was 12% lower with the use of RAS inhibitors. In the group that had risk factors, RAS inhibitor use was associated with a 13% reduction in the risk of MACE. In the group who did not have risk factors, RAS inhibitor use was associated with a 25% reduction in the risk of MACE. 

This study showed that RAS inhibitors are beneficial for all patients who undergo CABG, not only those with risk factors. 

This study is based on medical records, further studies are needed to confirm these results.