Ischemic Preconditioning Improves Cardiac Function in Off-pump CABG Patients

In patients undergoing off-pump coronary artery bypass grafting (CABG), regional ischemic preconditioning (IP) enhances postoperative myocardial performance, according to a recent report.

Dr. Matti R. Tarkka and colleagues, from Tampere University Hospital in Finland, assessed the outcomes of 32 patients with coronary artery disease who were randomized to undergo off-pump CABG with or without regional IP. All of the patients had disease of the left anterior descending coronary artery (LAD) with or without involvement of one other vessel.

The IP protocol involved two cycles of LAD occlusion for 2 minutes followed by 3 minutes of LAD reperfusion before the first coronary vessel was bypassed, the authors note in the April issue of Chest.

IP-treated patients demonstrated complete recovery of the mean stroke volume index postoperatively, while control subjects had significantly reduced indices. IP-treated patients also experienced a significantly lower increase in the mean heart rate postoperatively. Finally, IP tended to decrease immediate myocardial enzyme levels.

The IP protocol was not associated with an increase in the duration of mechanical ventilation, the length of stay in the intensive care unit, nor the use of inotropic medications, the researchers state.

The current IP protocol “proved to be applicable and safe in patients undergoing off-pump myocardial revascularization, it tended to decrease the immediate myocardial enzyme release, it prohibited the postoperative increase in heart rate, and it enhanced the recovery of stroke volume index,” Dr. Tarkka’s team notes.

Chest 2002;121:1183-1189.