Evaluation of the Right Ventricle Function Conducted in Patients after Acute Myocardial Infarction, Using Threedimensional Echocardiography and Myocardial Strain Analysis. Summary of the Doctoral Thesis

It is well known that dysfunction of the right ventricle in ST segment elevation myocardial infarction causes such complications as rhythm disturbances, cardiogenic shock and others. Its presence is an independent prognostic indicator of all-cause mortality, cardiovascular mortality and development of heart failure. However, in clinical practice still too little attention is paid to the evaluation of the right ventricle function, despite the new echocardiographic methods available, which are capable of providing an accurate diagnostics of the right ventricle disfunction. The purpose of this work is to evaluate changes in the systolic function of the right ventricle in patients with proven acute ST elevation myocardial infarction by threedimensional echocardiography and myocardial strain techniques, and to select the most informative echocardiographic parameters for the size and function of the right ventricle for use in everyday practice. Based on the data gained during this study, the algorithm for the evaluation of the right ventricle function in patients with acute ST elevation myocardial infarction will be developed. A healthy individuals control group and a group of patients with ST elevation myocardial infarction were formed within the study. Each participant was examined according to standart echocardiography protocol. In each case new echocardiographic right venricle function evaluation methods also were applied – a three-dimensional echocardiography with following right ventricle reconstruction, volume and ejection fraction determination, as well as myocardial longitudinal strain measurements. Based on these methods, by comparing the data to the control group results, it was possible to etermine the pathology threshold for the right ventricular ejection fraction and longitudinal strain to detect right ventricle disfunction in the case of acute myocardial infarction. Three-dimensional echocardiography and evaluation of myocardial strain are new, relatively simple, sufficiently sensitive and specific methods for the diagnosis of right ventricular dysfunction in patients with ST elevation myocardial infarction. The methods are to be introduced for use in everyday clinical practice along with the standard ehocardiography parameters, which also change in ST elevation myocardial infarction: fractional area change, tricuspid annular plane systolic excursion, and visual evaluation of segmental systolic function of the right ventricle. Among new parameters ejection fraction of the right ventricle and right ventricle free wall longitudinal strain have to be determined. When evaluating the right chamber, it should be remembered that its function deterioration can be observed in case of myocardial infarction of any localization.

Serum insulin is associated with right ventricle function parameters and lung volumes in subjects free of cardiovascular disease

Background Diabetes mellitus is an established risk factor for cardiovascular diseases. Even impaired levels of glucose and insulin might harm organ function prior to diabetes onset. Whether serum glucose or insulin plays a direct role in cardiac dysfunction or lung volume reduction remains unclear. The aim was to investigate the relationship between glucose and insulin with the right ventricle and lung volumes within KORA-MRI FF4 study. Methods From the KORA-MRI FF4 cohort study 337 subjects (mean age 55.7 ± 9.1 years; 43% women) underwent a whole-body 3T MRI scan. Cardiac parameters derived from a cine-steady-state free precession sequence using cvi42. MRI-based lung volumes derived semi-automatically using an in-house algorithm. Fasting serum glucose, fasting insulin levels, and HOMA index were calculated in all study subjects. Linear regression analyses were performed to assess the relationships between glucose and insulin levels with right ventricle volumes and lung volumes adjusted for age, sex, BMI, and cardiovascular risk factors. Results In univariate and multivariate-adjusted models, high serum insulin was inversely associated with end-diastolic volume (β = −12.43, P < 0.001), end-systolic volume (β = −7.12, P < 0.001), stroke volume (β = −5.32, P < 0.001), but not with ejection fraction. The association remained significant after additional adjustment for lung volumes. Similarly, serum insulin was inversely associated with lung volume (β = −0.15, P = 0.04). Sensitivity analysis confirmed results after excluding subjects with known diabetes. Conclusions Serum insulin was inversely associated with right ventricle function and lung volumes in subjects from the general population free of cardiovascular disease, suggesting that increased insulin levels may contribute to subclinical cardiopulmonary circulation impairment.