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Cardiac diseases of cattle may involve valvular structures, myocardium, pericardium, or blood vessels and are manifested by the clinical signs of cardiac dysrhythmias, cardiac murmurs, generalized edema, muffled heart sounds, jugular venous distention, jugular venous pulsations, pulmonary edema, pleural effusion, or ascites. Digoxin, quinidine, and furosemide can be used effectively to control signs of CHF and cardiac arrhythmias. Combination antimicrobial therapy can be successful for cows with infective endocarditis and thrombophlebitis. Pericardial fluid drainage may temporarily improve cattle with traumatic pericarditis or lymphosarcoma so that short-term goals may be reached.

The prostaglandin-thromboxane system, platelet hemostasis and central hemodynamics were evaluated in 51 patients with heart failure-complicated acute myocardial infarction during aspirin, roxicam and basic (nitrates + cardiac glycosides + diuretics) therapies. The new non-steroidal antiinflammatory agent roxicam was shown to selectively inhibit thromboxane, without affecting prostacyclin levels. The agent may be regarded as the drug of choice in using antiaggregatory therapy in patients with myocardial infarction concurrent with heart failure.

Heart failure, cause notwithstanding, is characterized by adaptive (but harmful) increases in sympathetic activity and hormone levels, as well as by abnormal cardiovascular reflexes. Such reflex derangements may contribute to neurohumoral excitation. Consequently, normalization of the reflexes may be an important determinant of the effectiveness of therapy.

An increased understanding of the pathophysiologic changes underlying CHF, advanced monitoring technology, and a wider array of drug therapy have improved the prognosis of patients with this disorder. These advances allow for greater individualization of therapy, improve patient compliance, and lower the incidence of undesirable side effects. Of course, with the increase in complexity of treatment choices comes the need for more knowledgeable practitioners who can select the most appropriate therapeutic approach. All practitioners also must make every effort to educate the patients about their disease, treatments, and necessary lifestyle changes so that optimal benefits can be realized.

Overall 75 patients with rheumatic mitral heart disease were examined for the effect of the clinical and echocardiography characteristics of central and intracardiac hemodynamics on the efficacy of the use of digoxin. The development of digoxin resistance in patients with the predominance of stenosis of the mitral opening depended to the greatest degree on the duration of heart decompensation, area of the mitral opening and duration of the phase of left ventricle relaxation; in patients with the predominance of mitral insufficiency, it depended on the level of endosystolic stress, pressure of left ventricle filling and duration of the phase of isometric left ventricle contraction. Based on the calculation of the information content of the parameters under study, a prognostic table was made. The use of the table allowed forecasting the development of glycoside resistance in 77.6% of cases.

The clinical aspects of the influence of cardiac glycosides on the sinus node and atrioventricular junction in health and dysfunction are reviewed. It has been shown that digitalis drugs do not produce any effect on sinus node automatism including that in dysfunction. Cardiac glycosides suppress enhanced atrioventricular conduction and do not affect it provided it remains within normal. The mechanisms by which cardiac glycosides may act are discussed: extracardiac, cholinomimetic (in the acute test and direct one) and influencing heart conduction components (when used continuously).

The effectiveness of treatment of 127 elderly and senile patients suffering from the ischemic heart disease, who underwent the endoscopic interventions for acute cholecystitis, have been analysed. Atraumaticity of endoscopic interventions, individual approach to the choice of a method for treatment of a patient and agreed with a therapeutist preoperative preparation, including prescription of the coronaro-active agents, cardiac glycosides, permitted in the majority of patients to achieve a positive result of treatment.

Synergism of gamma radiation with 137Cs and cardiac glycosides was investigated in experiments on mice and transplantable Raji tumor cells. A single ip administration of these drugs at nontoxic concentrations 30-60 min. after irradiation at the LD30/30 resulted in the survival of 13-20% of animals and the reduction of the mean survival time up to 8.4-12.5 days versus 22.3 days in the control group. Synergism was slightly decreased at administration of glycosides 24 h after irradiation. Glycosides introduced in the irradiated (at a dose of 1-2.5 Gy) human lymphoblastic line caused sharp suppression of lymphoma growth and cellular lysis in experiments in vitro. One hundred per cent death of cells was noted after the use of the drugs at mean toxic concentrations.

The review presents the data on endogenous digitalis-like substances the effects of which are imitated by administered cardiac glycosides. It is suggested that the individual differences in the responses of patients to cardiac glycosides, a great range of doses of the drugs causing intoxication as well as the absence of a close correlation between the occurrence of therapeutic and toxic effects and blood plasma glycoside concentration are related to the change of the level of endogenous digitalis-like substances in the organism. The further study of the chemical structure of digitalis-like substances and the mechanism of their secretion opens up new possibilities for practical medicine.

In 105 patients with acute myocardial infarction the intake of glycosides and diuretics according to indication was controlled in the period from the end of the acute phase up to the first year. Despite lacking clinical signs of a cardiac insufficiency the treatment established in the clinic was performed in an unchanged way up to the first year. It is the common task of the family doctors and cardiologists to take part in a scientific prescription of glycosides and diuretics after infarction.

Nonspecific circulating immune complexes (CIC), different in size and stability, are detectable in the blood sera of patients with myocardial infarction; changed concentration of these complexes appears to be a reflection of the defense response of the body, aimed at homeostasis maintenance. No relationship between cardiac glycosides and CIC levels was revealed in patients with myocardial infarction. A reduction of the level of 'large' CICs by days 21-30 of the condition was observed in the patients treated with anticoagulants from the first day of the disease. A low CIC level in the acute period of the disease is a prognostically unfavorable sign in respect of the outcome of the condition.

The narrow therapeutic range of cardiac glycosides continually challenges chemists to synthetize new derivatives with improved therapeutic properties. One of the best investigated semi-synthetic glycosides is 16 alpha-gitoxin. Compared to ouabain and gitoxin, it produces positive inotropic effects on the isolated guinea-pig heart in a wider range of concentrations and causes less pronounced rhythmic disturbances. These results were confirmed by electrophysiological investigations in isolated fibres of the canine myocardium and of the Purkinje system, by investigations in the anaesthetized cat and dog and in healthy volunteers. The effects of various semi-synthetic compounds (e.g. actodigin, ASI-222) are described and possibilities to trigger these effects are discussed. Of some significance seem to be differences in the structure of the (Na+ + K+)-ATPase system of different tissues, e.g. the working muscle and the Purkinje system of the heart, as well as differences due to the formation and dissociation of the glycoside-enzyme complex. The significance of K+, Ca2+ and of several pharmacokinetic parameters (e.g. the volume of distribution) for these reactions are briefly discussed.

In 30 test persons (15 patients with disturbed function of the sino-auricular node, 9 of them with classical sick-sinus-syndrome as well as 15 test persons without disturbance of the sino-auricular node, of them 7 healthy ones) the influence of diphenylhydantoin on the function of the sino-auricular node was tested. By means of atrial stimulation the so-called sino-atrial conduction time, the recreation time of the sino-auricular node as well as the duration of the sinus period before and after intravenous application of 250 mg of diphenylhydantoin was estimated. The auricular stimulation was carried out either through an oesophageal electrode probe or usually through an electrode catheter directly placed in the right atrium. In the entire collective the sino-atrial conduction time did prolong itself statistically not significantly by 2 +/- 5ms (x +/- 2 s), in which cases there was not to be observed a different behaviour between test persons with a healthy rhythm and patients with disturbed function of the sino-auricular node. In 2 patients with sick-sinus-syndrome, however, after diphenylhydantoin and individual atrial stimulation in each case sino-atrial blockings of higher degree developed. The maximum absolute and corrected recovery time of the sino-auricular node prolonged itself in patients with syndrome of the sino-auricular node by on an average 1406 +/- 2120 ms or 1378 +/- 2338 ms, in which cases in 1 test person a threatening prolongation of the poststimulation pause to 10 s developed. In another patient after application of diphenylhydantoin an atrial arrest was observed. The automatism of the sino-auricular node of test persons with healthy rhythm was not influenced.

14 males at the age of 49 +/- 6.4 years with condition after myocardial infarction were loaded on the bicycle ergometer according to the criteria of the WHO. After injection of a beta-receptor blocker at the submaximal functional level the product of the pressure frequency decreased by 25% and the watt-pulse increased by 17%. The oxygen pulse and the respiratory quotient remained constant. An additional injection of glycosides did not significantly change these parameters. At the same time no falsely positive evidence concerning the behaviour of the ST-distance as criterium of withdrawal was provoked. The results of the submaximal and symptom-limited function were not falsified in the therapy with beta-receptor-blockers and glycosides, when the criteria of withdrawal recommended by the WHO are used unchangedly.