Perioperative myocardial protection with the calcium antagonist diltiazem.
The effect of the calcium channel blocker, diltiazem, on cardiac performance was examined in 90 patients who underwent isolated aortic valve replacement for aortic valve diseases with marked left ventricular hypertrophy. The patients were randomly assigned to one of five groups dependent on the treatment plan with diltiazem: group 1, 5-day preoperative treatment with oral administration of 60 mg diltiazem 3 times daily, 10 mg diltiazem intravenously as a bolus dose before the beginning of the cardiopulmonary bypass, and 5 mg diltiazem intravenously 10 min before removal of aortic clamp; group 2, 5-day preoperative treatment with oral administration of 60 mg diltiazem 3 times daily; group 3, 10 mg diltiazem intravenously as a bolus dose before the beginning of CPB and 5 mg 10 min before removal of the aortic clamp; group 4, 15 mg diltiazem in 1000 ml cardioplegic solution, given as additive; group 5, control group not receiving diltiazem. All operative procedures were performed in an identical manner with an average cross-clamping time of 57.7 min and cooling the heart down to 16 degrees-17 degrees septal temperature by perfusion of the coronary arteries with 4 degrees C cold cardioplegic solution. In each patient the heart rate (HR), cardiac output and cardiac index (CO, CI), stroke volume index (SVI), left ventricular stroke work index (LVSWI) and systemic vascular resistance index (SVRI) were recorded and calculated before and after the ischemic period. Transmural samples were obtained three times by needle biopsy technique from the anterior free wall of the heart. Analysis of the variables revealed that: (1) complete cessation of electromechanical activity was achieved significantly more rapidly in groups 1 and 3 than in the other groups; (2) recovery of sinus rhythm and function of the conductive system required significantly longer in groups 1 and 3; (3) the time-related values of the important hemodynamic factors (CO, CI, LWSVI and SVRI) showed a significantly more effective postperfusion cardiac performance in groups 1 and 3 than in groups 2, 4 and 5. An oral dose of 180 mg diltiazem for 5 to 7 days preoperatively in combination with intravenous administration of 10 mg before the beginning of CPB and 5-10 mg during reperfusion can be recommended in patients undergoing open-heart surgery for isolated aortic valve diseases and left ventricular hypertrophy.
Tschirkov
A
A
Department of Thoracic and Cardiovascular Surgery, Medical Academy, Sofia, Bulgaria.
Mishev
B
B
Natschev
G
G
Petkov
R
R
Alexandrov
V
V
Jurukova
Z
Z
D000284:Administration, Oral; D001022:Aortic Valve Insufficiency / Q000503:physiopathology / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000503:physiopathology / Q000601:surgery*; D002303:Cardiac Output, Low / Q000503:physiopathology / Q000517:prevention & control; D004110:Diltiazem / Q000008:administration & dosage*; D004334:Drug Administration Schedule; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D006327:Heart Block / Q000503:physiopathology / Q000517:prevention & control; D006333:Heart Failure / Q000503:physiopathology / Q000517:prevention & control*; D006350:Heart Valve Prosthesis; D006439:Hemodynamics / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects* / Q000502:physiology; D009206:Myocardium / Q000473:pathology; D011183:Postoperative Complications / Q000503:physiopathology / Q000517:prevention & control*; D011292:Premedication; D013318:Stroke Volume / Q000187:drug effects / Q000502:physiology
D004110:Diltiazem