Electrical impedance measurement as a method for evaluat ing myocardial protection in heart surgeries with artificial blood circulat ion

Intraoperative myocardial protection methods improvements is one of the most pressing problem of modern “open heart” surgery. To determine the myocardial metabolism condition after cardioplegic ischemia, methods as: assessment of the heart using electro- and echocardiography, assessment of the clinical condition, the need to use inotropic drugs, determining the level of biochemical markers of damage (lactate, myoglobin, troponin, etc.) are used in modern medicine as well as biopsy morphological examination.
Now there is no reliable diagnostic method in clinical practice that can determine the myocardial metabolism condition.
The purpose of the study is to determine the electrical impedance effectiveness as a method for evaluating myocardial protection in various cardioplegic modifications.
The study included 54 patients operated in A.N.Bakulev National Medical Centre of the Russian Academy of medical Sciences in Emergency surgery of acquired heart defects department for valvular heart apparatus defects, including combination with coronary artery pathology.
Depending on the method of myocardial protection, patients were divided into 3 groups:
Group 1 - patients who had buckberg cardioplegia as a myocardial protection (n=31); Group 2 - patients operated under pharmacoholodic cardioplegia using Custodiol solution (n=9); Group
3 - patients who used hyperkalic solution No. 3 (n=14) as intraoperative myocardial protection.
The bioelectric impedance of the myocardium was studied in all patients. To assess the myocardial protection adequacy and to compare it with the results of electrical impedance measurement, we also used some common research methods. The study results revealed that electrical impedance measurement is quite good at assessing the state of the myocardium during surgery.