Burnout, lifestyle and relaxation among dentists in Lithuania: a cross-sectional study

Background The aim of this study was to estimate the association of burnout level with lifestyle and relaxation among dentists in Lithuania. A better understanding of this association could help in the development of targeted interventions to prevent burnout among these professionals. Methods The survey was conducted among practising dentists (N = 380) using the Maslach Burnout Inventory (MBI) and an authors’ proposed scale to measure lifestyle and relaxation. Poisson regression was applied to examine the association between variables. Results Regular cigarette smoking among dentists in Lithuania was 16.8 % and alcohol consumption was 31.3 %. Some forms of active relaxation were also common: regular playing sports (57.9 %), and spending time in nature (61.4 %). Emotional exhaustion (EE) and depersonalization (DP) burnout dimensions were negatively related to the regular use of illegal substances, alcohol, medication and smoking, while personal achievement (PA) was negatively related to smoking only. Dentists who regularly exercised had significantly lower EE and DP sum scores, and better assessments of PA. There were also positive relationships of EE, DP and PA sum scores with the variables of relaxation (e.g., spending time with family or friends, visiting a theatre, engaging in art, listening to music). Conclusions It was concluded that the burnout dimensions are negatively associated with unhealthy lifestyle factors and positively associated with active relaxation among dentists in Lithuania. Therefore, burnout prevention should target specific lifestyle and relaxation improvement strategies.

MRCP as a Biomarker of Motor Action with Varying Degree of Central and Peripheral Contribution as Defined by Ultrasound Imaging

Introduction: Motor imagination is an alternative rehabilitation strategy for people who cannot execute real movements. However it is still a matter of debate to which degree it involves activation of deeper muscle structures, which cannot be detected by surface electromyography (SEMG). Methods: Eighteen able bodied participants performed cue based isometric ankle plantar flexion (active movement) followed by active relaxation under four conditions: executed movements with two levels of muscle contraction (fully executed and attempted movements, EM and AM) and motor imagination with and without detectable muscle twitches (IT and I). Most prominent peaks and distinctive phases of Movement Related Cortical Potential (MRCP) were compared between conditions. Ultrasound imagining (USI) and SEMG were used to detect movements. Results: IT showed spatially distinctive significant difference compared to both I and AM during active movement preparation and re-afferentation phase; further wide spread differences were found between IT and AM during active movement execution and posteriorly during preparation for active relaxation. EM and AM showed largest difference frontally during active movement planning and posteriorly during executing of active relaxation. Movement preparation positivity P1 showed significant difference in amplitude between IT and AM but not between IT and I. Conclusion: USI can detect subliminal movements (twitches) better than SEMG. MRCP is a biomarker sensitive to different levels of muscle contraction and relaxation. IT is a motor condition distinguishable from both I and AM. Significance: EEG biomarkers of movements could be used to identify pathological conditions, that manifest themselves during either active contraction or active relaxation.

Biomechanics of diastolic dysfunction: a one-dimensional computational modeling approach

This study uses a complete and validated computational model of the cardiovascular system to simulate the two main pathologies involved in diastolic dysfunction (DD), i.e., abnormal active relaxation and increased ventricular diastolic stiffness. The three phenotypes of DD were successfully replicated according to literature data. We elucidate the biomechanical effect of the relaxation pathologies involved and how these pathologies interact to create the various phenotypes of DD.

Pressure-volume analysis reveals characteristic sex-related differences in cardiac function in a rat model of aortic banding-induced myocardial hypertrophy

Sex differences in pressure overload (PO)-induced left ventricular (LV) myocardial hypertrophy (LVH) have been intensely investigated. Nevertheless, sex-related disparities of LV hemodynamics in LVH were not examined in detail. Therefore, we aimed to provide a detailed characterization of distinct aspects of LV function in male and female rats during different stages of LVH. Banding of the abdominal aorta (AB) was performed to induce PO for 6 or 12 wk in male and female rats. Control animals underwent sham operation. The development of LVH was followed by serial echocardiography. Cardiac function was assessed by pressure-volume analysis. Cardiomyocyte hypertrophy and fibrosis were evaluated by histology. At week 6, increased LV mass index, heart weight-to-tibial length, cardiomyocyte diameter, concentric LV geometry, and moderate interstitial fibrosis were detected in both male and female AB rats, indicating the development of an early stage of LVH. Functionally, at this time, impaired active relaxation, increased contractility, and preserved ventricular-arterial coupling were observed in the AB groups in both sexes. In contrast, at week 12, progressive deterioration of LVH-associated structural and functional alterations occurred in male but not female animals with sustained PO. Accordingly, at this later stage, LVH was associated with eccentric remodeling, exacerbated fibrosis, and increased chamber stiffness in male AB rats. Furthermore, augmented contractility declined in male but not female AB animals, resulting in contractility-afterload mismatch. Maintained contractility augmentation, preserved ventricular-arterial coupling, and better myocardial compliance in female rats contribute to sex differences in LV function during the progression of PO-induced LVH. NEW & NOTEWORTHY We investigated sex differences in pressure overload-induced left ventricular myocardial hypertrophy for the first time on the functional level by pressure-volume analysis. We found that left ventricular hypertrophy was initially characterized by prolonged active relaxation, increased contractility, and maintained ventricular-arterial coupling in both sexes. However, at a later stage, augmented contractility declined in mate but not female rats, resulting in contractility-afterload mismatch. Furthermore, in male rats, increased myocardial stiffness also contributed to hypertrophy-associated diastolic dysfunction.

Evaluating of the effectiveness and safety of the reproduced selective β1-blocker without intrinsic sympathomimetic activity Bidop® in patients with hypertrophic cardiomyopathy

The article assesses the effectiveness of therapy generics Bidop® production of Gedeon Richter (Hungary), designated to improve diastolic function, and treatment of heart failureof patients with hypertrophic cardiomyopathy with predominant hypertrophy of the interventricular septum and symmetrical concentric shape in the absence of obstruction of outflow tract of the left ventricle (LV). The effect of the presence of zones of intramyocardial fibrosis hypertrophied LV departments identified through MRI delayed contrast, to the process of active relaxation.

Physiological and pathological left ventricular hypertrophy of comparable degree is associated with characteristic differences of in vivo hemodynamics

Left ventricular (LV) hypertrophy is a physiological or pathological response of LV myocardium to increased cardiac load. We aimed at investigating and comparing hemodynamic alterations in well-established rat models of physiological hypertrophy (PhyH) and pathological hypertrophy (PaH) by using LV pressure-volume (P-V) analysis. PhyH and PaH were induced in rats by swim training and by abdominal aortic banding, respectively. Morphology of the heart was investigated by echocardiography. Characterization of cardiac function was completed by LV P-V analysis. In addition, histological and molecular biological measurements were performed. Echocardiography revealed myocardial hypertrophy of similar degree in both models, which was confirmed by post-mortem heart weight data. In aortic-banded rats we detected subendocardial fibrosis. Reactivation of fetal gene program could be observed only in the PaH model. PhyH was associated with increased stroke volume, whereas unaltered stroke volume was detected in PaH along with markedly elevated end-systolic pressure values. Sensitive indexes of LV contractility were increased in both models, in parallel with the degree of hypertrophy. Active relaxation was ameliorated in athlete's heart, whereas it showed marked impairment in PaH. Mechanical efficiency and ventriculo-arterial coupling were improved in PhyH, whereas they remained unchanged in PaH. Myocardial gene expression of mitochondrial regulators showed marked differences between PaH and PhyH. We provided the first comparative hemodynamic characterization of PhyH and PaH in relevant rodent models. Increased LV contractility could be observed in both types of LV hypertrophy; characteristic distinction was detected in diastolic function (active relaxation) and mechanoenergetics (mechanical efficiency), which might be explained by mitochondrial differences.

Abstract 10878: Validation of Non-invasive Measures of Diastolic Function in Children: A Simultaneous Echocardiography and Conductance Catheterization Study

Introduction: The accuracy of echocardiography in evaluating left ventricular (LV) diastolic function has not been validated in children. The objective of this study was to compare echocardiographic and gold-standard measures of LV diastolic function in children. Methods: Patients undergoing routine left heart catheterization were prospectively enrolled. Pressure-volume loops (PVL) were obtained via conductance catheters. The end-diastolic pressure-volume relationship was obtained via balloon occlusion of the vena cavae. PVL measures of diastolic function were divided into early active relaxation (the isovolumic relaxation time constant, tau), and ventricular stiffness (the chamber stiffness constant, β). End-diastolic pressure (EDP) was also recorded. Echocardiographic measures of diastolic function were derived from spectral Doppler, tissue Doppler, and 2D speckle-tracking. The relationships between PVL and echocardiographic measures were determined using Spearman’s correlation. Results: Of 24 patients, 18 patients were s/p heart transplant, 5 patients had a small patent ductus arteriosus or coronary fistula. Mean age was 9.1 ± 5.6 years. The median τ was 24.9 ms (IQR 22.8 - 28.4 ms), median β was 0.094 (IQR 0.035 - 0.154), and median EDP was 9 mmHg (IQR 8 - 13 mmHg). Statistically significant correlations between invasive and echocardiographic measures of diastolic function are reported in the Table. No echocardiographic measures correlated with β. Conclusion: Early diastolic echocardiographic measures correlate with tau and may accurately represent early active relaxation in children. Modest associations exist between echocardiographic measures and EDP. The use of these non-invasive measures in accurately assessing LV diastolic function appears promising in children. However, no echocardiographic measures correlate with chamber stiffness. The development of such measures merits further study.