Summary
This study was undertaken to evaluate the potential role of a perioperative calcium-channel blocker (Diltiazem) infusion in improving myocardial preservation.
Forty consecutive CAD patients were randomly assigned to a control (C; n = 20) and a treated (D; n = 20) group. In patients in the latter group diltiazem was continuously infused at 0.5 to 2.0 mcg/kg/min i.v. from anesthesia induction until the aortic cross-clamping, and from myocardial reperfusion till the 48th postoperative hour.
During the preCPB phase hypertension occurred less frequently in group D (3 vs 12 cases, p = 0.0033). In the immediate postischemic period, depression of contractility and the need for inotropic support were observed in 3 cases in group D and in 9 in group C (p = 0.0384).
Postoperatively, group D patients had a lower incidence rate of hyperkinetic arrhythmias or conduction disturbances (p = 0.0218), as well as of ECG signs of ischemia (p = 0.0016). Significant CK enzyme level increase was noted in 13 patients in group C versus 4 in group D (p = 0.0040). Two perioperative myocardial infarctions were diagnosed, both in group C.
These clinical data show that continuous perioperative infusion of diltiazem can effectively increase myocardial preservation during ischemic arrest, without unfavorable effects on the hemodynamics, electrical activity or mechanical performance of the heart.
Key words
Calcium channel blockers - Diltiazem - Ischemic arrest - Myocardial protection - Perioperative myocardial infarction
