Cutting off blood flow in the arm temporarily may leave some heart surgery patients better off after the procedure.
Researchers from London looked at 57 patients having elective coronary artery bypass graft surgery. All participants had the amounts of troponin T in their blood measured before surgery and also at six, 12, 24, 48 and 72 hours after surgery. Troponin T is a cardiac protein sometimes released into the bloodstream after an “injury” to the heart during surgery. Previous research has associated release of the proteins with poor clinical outcomes after surgery.
For the study, researchers performed remote ischemic preconditioning on 27 study participants. The technique involves three five-minute cycles of an automated cuff-inflator restricting blood flow in one arm with five-minute periods between each cycle where the cuff was deflated. The other 30 participants were in the control group and did not undergo the treatment.
Researchers report the total troponin T released 72 hours after surgery went down 43 percent — from 36.12 in the control group to 20.58 in the remote ischemic preconditioning group.
In an accompanying comment, Henry Purcell and John Pepper, from the Royal Brompton Hospital in London, write, “Clearly the technique for remote ischemic preconditioning needs to be duplicated by equally skilled workers in other cardiac centers in large numbers of patients. In the meantime, if intermittent limb occlusions are consistently shown to reduce myocardial injury during cardiac revascularization, the implications for practice are immense.”
SOURCE: The Lancet, 2007;370:575-79