Biopsy assessment of preservation during open-heart surgery with cold cardioplegic arrest

The efficacy of cold cardioplegic arrest as a method of myocardial preservation has been evaluated by cytochemical and biophysical assessments made on needle biopsies taken from 150 patients undergoing open-heart surgery (e.g., aortic valve replacement, aortic and mitral valve replacement, mitral valve replacement, coronary artery bypass graft, repair of atrial or ventricular septal defects). Comparison of endo- and epicardial preservation showed improved endocardial preservation with cardioplegia compared with that achieved with the previous method used--continuous coronary perfusion at 32 degrees C; however, care had to be taken to ensure adequate cooling of the epicardium. Biopsies also showed the need for repeated infusions of cardioplegic solution if the aorta was occluded for more than 70 min. Preservation of right and left ventricle has also been compared.