[Effect of cardioplegia on nitrogen and energy metabolism of the human heart].

The interrelation between the energy and nitrogenous metabolism of the myocardium during cardioplegia has been studied in patients with congenital valvular heart disease (tetralogy of Fallot--12 patients, ventricular septal defect--5 patients). Whole body hypothermia with repeated heart reperfusion with cold cardioplegic blood perfusate was used for the protection of the myocardium. However, ATP level of the myocardium of some patients decreased by 20% and more of the baseline.

Glutamate-blood cardioplegia improves ATP preservation in human myocardium.

Two groups of patients subjected to radical correction of Fallot's tetrad and defects of interventricular septum were investigated to ascertain whether the addition of glutamic acid to blood cardioplegic perfusate could improve preservation of myocardial ATP during cardiac arrest. In the control group (17 patients) the myocardial protection was performed by repeated infusions of cold blood potassium cardioplegic solution; in the 2nd group (24 patients) cardioplegic perfusate containing glutamic acid (20 mmol/l) was used. Left ventricular biopsies were taken during the first minute after cross-clamping of the aorta and before the release of the aortic clamp to determine ATP, glutamate and lactate.

Ischemic heart arrest: nitrogenous metabolism in energy-depleted human myocardium.

Seventeen patients undergoing radical correction of Fallot's tetrad or defects of interventricular septum were investigated. Needle biopsies from the left ventricular apex region were obtained at the 1st min after cross-clamping of the aorta and at the end of cardiac arrest to determine adenosine triphosphate (ATP), glutamate, aspartate, alanine and ammonia. The losses of ATP during clamping period were related to decrease in glutamate.

[Laser endoscopic destruction of the atrioventricular junction of the heart conduction system in an experiment].

Feasibility and degree of local AV junction destruction were studied prior to the induction of complete transversal block on the model of 18 isolated perfused dog hearts, using endoscopic laser device, employing cardiofibroscope and laser Ne: YAG. Morphological pattern in the destruction zone is presented. The technique and device can be used for transvenous AV junction destruction.

[Effect of cooling on rhythmo-inotropic relations in pathologically altered myocardium].

Fragments of the right atrium auricle from patients with congenital and acquired heart diseases were used to study the effect of the Tyrode solution temperature over the 60-minute cessation of electrical stimulation of the preparations on the recovery of the amplitude of rhythmic contractions after the pause. The lack of stimulation within 34 to 24 degrees C does not lower the contraction amplitude after warming of the preparations and renewal of rhythmic stimulation. The hypothermal pause at a temperature of 10-14 degrees C leads to the development of contractures and suppresses the myocardial contractility.

[Pulmonary artery aneurysm].

The article is concerned with the questions of etiology, pathogenesis and classification of the aneurysm of the pulmonary artery. Two cases observed by the authors are described. A 38-year-old patient had idiopathic aneurysm of the trunk and the right pulmonary artery.

[Recurrent right-ventricular hypertrophy in patients with congenital isolated stenosis of the pulmonary artery and outlet tract of the right ventricle in the immediate and late periods after surgery].

The degree of hypertrophy of the right ventricle is proportionate to the size of the systolic pressure gradient between the right ventricle and pulmonary artery prior to operation. The involution of hypertrophy is dependent on the type of stenosis, age of the patient and the term of surgery.