Diabetes mellitus type 2 and acute myocardial infarction: prognostic options for interaction in patients of different age groups

Background. Problems surrounding comorbidities of type 2 diabetes mellitus and coronary heart disease are some of the most important in medical science and practice, given their mutually negative impact on patients prognoses and quality of life. Aims. To study the impact of type 2 diabetes on the long-term prognoses of patients of different age categories, status-post acute myocardial infarction. (Data obtained from the Register of Acute Myocardial Infarction.) Materials and methods. The main data source was the Register of Acute Myocardial Infarction, maintained in Tomsk for more than 30 years. The study included 862 patients with acute myocardial infarction. The patients were monitored for 5 years. The primary endpoint was death from any cause during the observation period. Results. We separated the study cohort into 2 groups depending on patients ages: Group 1 (n = 358) included patients older than working age, Group 2 (n = 504) consisted of younger, employable patients. The combination of ischaemic heart disease and type 2 diabetes mellitus were diagnosed in 208 patients. The combination of ischaemic heart disease and type 2 diabetes was the cause of adverse prognosis among elderly patients and led to increased mortality rate during the 5-year post-infarction period (p = 0.0003). However, among younger, working patients who suffered myocardial infarction, the presence of type 2 diabetes did not have an independent negative effect on long-term disease prognosis. While in employable patients, a long history of diabetes mellitus significantly aggravated the course of the post-infarction period (p = 0.004). Conclusions. These data suggest an ambiguous prognostic effect of type 2 diabetes mellitus among working age and elderly patients status post myocardial infarction, in agreement with experimental studies conducted on laboratory animals. Further comprehensive analyses of the clinical and experimental data are needed to optimise therapies for patients who suffer from type 2 diabetes and comorbid ischaemic heart disease

Rhythminotropic Reactions of Human Myocardium in Ischemic and Rheumatic Heart Diseases against the Background of Amiodarone

In human heart failure, Ca2+ homeostasis gets disturbed due to a decrease in the function of the sarcoplasmic reticulum (SR). We studied the differences in the SR function in patients with rheumatic and coronary heart disease, against the background of amiodarone. Cardiac preparations from the atrium of 21 patients with coronary artery disease (CAD) and 14 patients with rheumatic heart disease (RHD) were used in this study. Myocardial strips perfused with oxygenated Krebs-Henzelait solution without and with amiodarone (1 mM/l) at 37°C. The steady state stimulation rate of the muscle strips was 0.5 Hz. The single extraordinary impulse was given as 0.2-1.5 sec after the steady state beat. Then, the first beat after a 4- to 60-sec rest period was evaluated. The extrasystoles of the myocardium in both groups, after long intervals, were decreased after amiodarone treatment. The amplitude of post extrasystoles of amiodarone-treated myocardium showed differences only after long intervals in both groups. Two types of inotropic responses of a failing myocardium after rest periods were observed. Type I post-rest contractions maintained the steady state amplitude after all rests. However, type II was characterized by a reduction in the amplitude of the contractions. Amiodarone treatment of the myocardium showing type I reactions led to an increase in the potentiation after rests, but showed no effect on the reaction of the muscle with the type II response. The results suggested that SR dysfunction was different in CAD and RHD. The realization of the therapeutic effect of amiodarone was found to be dependent on the functional activity of the SR

Comparative Analysis of Changes of Myocardial Angiogenesis and Energy Metabolism in Postinfarction and Diabetic Damage of Rat Heart

Comparative study of changes in myocardial activity of lactate dehydrogenase (LDH), succinate dehydrogenase (SDH), and capillary density distribution in the experimental models of diabetic and postinfarction damage of rat heart was performed. Data showed that decrease in LDH and SDH activities was observed in both pathologies which can suggest abnormal processes of glycolysis and oxidative phosphorylation in cardiac mitochondria. Activity of LDH and SDH in combined pathologies was comparative with the corresponding values of these parameters in control group. The authors hypothesize that these differences can be caused by specifics of myocardial vascularization. The results of the study showed that an increase in capillary density was found in all groups of rats with pathologies compared with control group. However, no significant differences in the intensity of angiogenesis processes were found between groups with pathologies