Intermittent antegrade tepid versus cold blood cardioplegia in elective myocardial revascularization.
BACKGROUND
The ideal temperature for blood cardioplegia administration remains controversial.


METHODS
Fifty-two patients who required elective myocardial revascularization were prospectively randomized to receive intermittent antegrade tepid (29 degrees C; group T, 25 patients) or cold (4 degrees C; group C, 27 patients) blood cardioplegia.


RESULTS
The two cohorts were similar with respect to all preoperative and intraoperative variables. The mean septal temperature was higher in group T (T, 29.6 degrees +/- 1.1 degrees C versus 17.5 degrees +/- 3.0 degrees C; p < 0.0001). After reperfusion, group T exhibited significantly greater lactate and acid release despite similar levels of oxygen extraction (p < 0.05). The creatine kinase-MB isoenzyme release was significantly lower in group T (764 +/- 89 versus 1,120 +/- 141 U x h/L; p < 0.04). Hearts protected with tepid cardioplegia demonstrated significantly increased ejection fraction with volume loading, improvement in left ventricular function at 12 hours, and decreased need for postoperative inotropic support (p < 0.05). The frequency of ventricular defibrillation after cross-clamp removal was lower in this cohort (p < 0.05). There were no hospital deaths, and both groups had similar postoperative courses.


CONCLUSIONS
Intermittent antegrade tepid blood cardioplegia is a safe and efficacious method of myocardial protection and demonstrates advantages when compared with cold blood cardioplegia in elective myocardial revascularization.
Fiore
A C
AC
Division of Cardiothoracic Surgery, Saint Louis University Health Sciences Center, Missouri 63110-0250, USA.
Swartz
M T
MT
Nevett
R
R
Vieth
P J
PJ
Magrath
R A
RA
Sherrick
A
A
Barner
H B
HB
D000368:Aged; D001769:Blood; D002306:Cardiac Volume / Q000502:physiology; D002314:Cardioplegic Solutions / Q000008:administration & dosage / Q000627:therapeutic use*; D002315:Cardiopulmonary Bypass / Q000009:adverse effects; D015331:Cohort Studies; D003080:Cold Temperature; D001026:Coronary Artery Bypass / Q000379:methods*; D003402:Creatine Kinase / Q000097:blood; D017558:Elective Surgical Procedures; D004554:Electric Countershock; D005260:Female; D006324:Heart Arrest, Induced / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007527:Isoenzymes; D007773:Lactates / Q000097:blood; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects / Q000502:physiology; D010101:Oxygen Consumption; D011446:Prospective Studies; D012449:Safety; D013318:Stroke Volume / Q000502:physiology; D016277:Ventricular Function, Left / Q000502:physiology
D002314:Cardioplegic Solutions; D007527:Isoenzymes; D007773:Lactates; D003402:Creatine Kinase