Responses of soccer players performing repeated maximal efforts in simulated conditions of the FIFA World Cup Qatar 2022: A holistic approach.

This study aimed to assess the capacity for repeated maximal effort (RME) of soccer players in the thermo-natural conditions (NC) and in simulated conditions for the 2022 FIFA World Cup in Qatar (QSC). Twenty-four semi-professional soccer players participated in the study. The exercise test consisted of ten 6-second maximal efforts on a cycloergometer. A 90-second passive rest interval was used. The test was performed in a Weiss Technik WK-26 climate test chamber in two different conditions: 1) thermo-neutral conditions (NC-20.5°C; 58.7% humidity); and 2) simulated conditions for the 2022 World Cup in Qatar (QSC-28.5 ± 1.92°C; 58.7 ± 8.64% humidity). Power-related, physiological, psychomotor, blood, and electrolyte variables were recorded. Results showed that (1) players achieved higher peak power (max 1607,46 ± 192,70 [W] - 3rd rep), needed less time to peak power (min 0,95 ± 0,27 [s] - 3rd rep), and had a higher fatigue slope (max 218,67 ± 59,64 [W/sek] - 7th rep) in QSC than in NC (in each repetition of study protocol); (2) between the 1st repetition and subsequent repetitions a number of significants in among physiological, blood-related, and electrolyte variables were noted, but their direction was similar in both simulated conditions (e.g. V'O2/kg 37,59 ± 3,96 vs 37,95 ± 3,17 [ml/min/kg] - 3rd rep, LAC 13,16 ± 2,61 vs 14,18 ± 3,13 [mg/dl] - 10th rep or K 4,54 ± 0,29 vs 4,79 ± 0,36 [mmol/l] - 2nd rep when compare QCS and NC respectively); (3) an 8°C of temperature difference between the climatic conditions did not significantly affect the soccer players' physical and physiological responses in RME. The study results can be used in the design of training programs aimed to increase players' physiological adaptations by simulating soccer-specific conditions of play in terms of anaerobic capacity, in particular, repetitive maximal efforts. These findings will be useful during the upcoming 2022 World Cup in Qatar and in locations where high ambient temperatures are customary.

Assessment of quality of life in patients after surgical and transcatheter aortic valve replacement.

OBJECTIVES: Transcatheter aortic valve implantation (TAVI) and minimally invasive aortic valve replacement (mini-thoracotomy, mini-sternotomy, MIAVR) have become an appealing alternative to conventional surgical (SAVR) treatment of severe aortic stenosis (AS) in high-risk patients. BACKGROUND: Aim of the study was to evaluate the quality of life (QoL) in patients with AS and treated with transfemoral TAVI, SAVR, mini-thoracotomy and mini-sternotomy. METHODS: One hundred and seventy-three patients with symptomatic AS were enrolled in 2011-2013. TAVI group consisted of 39 patients (22.5%), mini-sternotomy was performed in 44 patients (25.5%), mini-thoracotomy in 50 (29%), and AVR in 40 patients (23%). QoL was assessed perioperatively, 12 and 24 months after aortic valve replacement (AVR) by Minnesota Living with Heart Failure Questionnaire (MLHFQ) and EQ-5D-3L. RESULTS: Median follow-up was 583.5 (IQR: 298-736) days. Improvement of health status after procedure in comparison with pre-operative period was significantly more often reported after TAVI in perioperative period (90.3%; P = 0.004) and 12 months after procedure (100%, P = 0.02). Global MLHFQ, physical and emotional dimension score at 30-day from AVR presented significant improvement after TAVI in comparison with surgical methods (respectively: 8.3(±8.6), P = 0.003; 4.1(±5.9), P = 0.01; 1.5(±2.6), P = 0.005). Total MLHFQ score was significantly lower (better outcome) in TAVI patients 1 year after procedure (4.8(±6.8), P = 0.004), no differences in somatic and emotional component were found. No differences were found in MLHFQ score 24 months after AVR. Data from EQ-D5-3L questionnaire demonstrated significant improvement of QoL at 30-day follow-up after TAVI in comparison with surgical methods (1.2(±1.7), P = 0.0008). CONCLUSIONS: TAVI improves QoL in perioperative and 12 months observation in comparison with mini-thoracotomy, mini-sternotomy and SAVR. Improvement in QoL was obtained in both generic and disease specific questionnaires. © 2016 Wiley Periodicals, Inc.

Distribution of selected elements in calcific human aortic valves studied by microscopy combined with SR-µXRF: influence of lipids on progression of calcification.

Calcified heart valves display a significant imbalance in tissue content of trace and essential elements. The valvular calcification is an age-related process and there are data suggesting involvement of lipids. We studied elemental composition and lipid distribution in three distinct regions of calcified human aortic valves, representing successive stages of the calcific degeneration: normal, thickened (early lesion) and calcified (late lesion), using SR-µXRF (Synchrotron Radiation Micro X-Ray Fluorescence) for elemental composition and Oil Red O (ORO) staining for demonstration of lipids. Two-dimensional SR-µXRF maps and precise point spectra were compared with histological stainings on consecutive valve sections to prove topographical localization and colocalization of the examined elements and lipids. In calcified valve areas, accumulation of calcium and phosphorus was accompanied by enhanced concentrations of strontium and zinc. Calcifications preferentially developed in lipid-rich areas of the valves. Calcium concentration ratio between lipid-rich and lipid-free areas was not age-dependent in early lesions, but showed a significant increase with age in late lesions, indicating age-dependent intensification of lipid involvement in calcification process. The results suggest that mechanisms of calcification change with progression of valve degeneration and with age.

Importance of evaluating conduction block in radiofrequency ablation for atrial fibrillation.

OBJECTIVE: Atrial fibrillation (AF) is the most frequently diagnosed cardiac arrhythmia. Anti-arrhythmic drugs may be used to suppress ectopic foci and interrupt reentry circuits, but are often insufficient to treat recurrent AF and have a number of adverse effects. Alternative therapies, such as catheter and surgical ablation, have been explored. This investigation examines the importance of assessing exit block when performing surgical ablation during beating-heart treatment of AF. METHODS: This was an evaluation of pooled data from multicenter prospective results obtained in AF patients who received ablation with a new, irrigated, vacuum-integrated device that creates linear lesions during beating-heart/open-chest or minimally invasive, port-access procedures. Electrocardiogram or Holter data were collected intra-operatively and at 1, 3, 6, and 12 months. Outcomes were also evaluated for patients who were or 'were not' tested for exit block following the ablation procedure. RESULTS: A total of 93 patients were treated (61 open-chest surgeries, 32 port-access procedures). There were no device-related complications and no operative mortality. At 341 days' average follow-up, 71/86 (83%) patients were free from AF, 66/86 (77%) were in sinus rhythm, and 60/86 (70%) were free from AF and off Class I and III anti-arrhythmic drugs (AADs). At 12 months, 23/23 (100%) patients with exit block confirmed were AF free compared with 13/21 (62%) patients with exit block not tested (p≤0.01, Fisher's exact test); 20/23 (87%) were in sinus rhythm compared with 12/21 (57%) patients with exit block not tested (p≤0.05, Fisher's exact test); and 20/23 (87%) were AF free without Class I and III AADs compared with 10/21 (48%) patients with exit block not tested (p≤0.01, Fisher's exact test). Both open-chest and port-access procedures yielded decreases in left-atrial size from baseline to 6 months' follow-up. Patients undergoing port-access procedures also observed an increase in left-ventricular ejection fraction, which was also significant at 6 months. CONCLUSION: Patients in whom exit block was confirmed following an ablation procedure were more likely to have successful clinical outcomes. Since testing for exit block must be performed on a beating heart, total epicardial beating-heart ablation may provide an important treatment for AF, providing intra-operative feedback indicative of long-term outcomes.

Estimation of muscle torque in various combat sports.

The purpose of the research was to compare muscle torque of elite combat groups. Twelve taekwondo WTF athletes, twelve taekwondo ITF athletes and nine boxers participated in the study. Measurements of muscle torques were done under static conditions on a special stand which belonged to the Department of Biomechanics. The sum of muscle torque of lower right and left extremities of relative values was significantly higher for taekwondo WTF athletes than for boxers (16%, p < 0.001 for right and 10%, p < 0.05 for left extremities) and taekwondo ITF (10%, p < 0.05 for right and 8% for left extremities). Taekwondo ITF athletes attained significantly higher absolute muscle torque values than boxers for elbow flexors (20%, p < 0.05 for right and 11% for left extremities) and extensors (14% for right and 18%, p < 0.05 for left extremities) and shoulder flexors (10% for right and 12%, p < 0.05 for left extremities) and extensors (11% for right and 1% for left extremities). Taekwondo WTF and taekwondo ITF athletes obtained significantly different relative values of muscle torque of the hip flexors (16%, p < 0.05) and extensors (11%, p < 0.05) of the right extremities.

Fresh-wet storage accelerates aortic homograft calcification.

The studies were focused on the influence of the fresh-wet storage procedure on aortic valve homograft (AVH) mineralization. Thirty-four aortic valves excised at autopsy were investigated. The cusps were divided into halves, the first one was used as a control while the second half was stored in Morgan, Morton, and Parker's Medium 199 supplemented with an antibiotic mixture at 4 degrees C for 28 days. The elemental compositions of the samples were determined by the energy dispersive X-ray fluorescence method. The Ca/P ratio and Ca concentration was used as markers of the mineralization development. It was found that the AVH mineralization was accelerated by the applied fresh-wet storage procedure. The aggravation of the AVH mineralization was correlated with the Ca content before storage especially in case of old donors. For donors older than 40 years an increase of Ca concentrations by approximately 40% was observed. To limit AVH mineralization due to fresh-wet storage, age of donors should not exceed approximately 40 years. Another method to reduce AVH mineralization relies on a modification of the medium commonly applied in the fresh-wet storage procedure, and research are ongoing.

[Effect of the dispersion of calcium deposits on allogenic aortic valves durability. Mineralization phases]. / Wplyw rozproszenia zlogów wapnia na trwalosc allogennych aortalnych zastawek serca. Fazowosc mineralizacji.

This investigation was aimed at comparison of calcium content and calcium dispersion in allogenic aortic valve leaflets removed due to dysfunction, to establish the influence of both parameters on graft durability. Calcification was assessed histochemically (von Kossa) as well as physicochemically using atomic absorption spectroscopy (AAS). The morpho-metric data (leaflet area involved in the calcification process) were obtained by computer-assisted image analysis system. The dry weight content of leaflet calcium and phosphorus were assessed by atomic absorptive spectroscopy (AAS) and Ca/P ratio was calculated. Calcium dispersion coefficient (Dc) was established according to the formula: Dc = 1/Ca(c)/Ap, where Ca(c) = calcium dry weight concentration; Ap = percent of leaflet area involved in calcification. We found biphasic correlation between calcium concentration and area involved in calcification. The first one was characterized by rising dispersion of calcium deposits while for the second one saturation with hydroxyapatite of formerly calcified areas was predominant, negatively influencing graft durability. Allograft durability was correlated with calcium dispersion (Dc) (p<0.001), while no significant correlation was found with calcium concentration. Decreased Dc was characteristic for 93.8% of low durability grafts (<11.6 years). Our results suggest that lowered calcium dispersion decreasing allograft lifetime and is a better predictor of allograft durability than the total calcium content.

Mechanisms of increased vascular superoxide production in human diabetes mellitus: role of NAD(P)H oxidase and endothelial nitric oxide synthase.

BACKGROUND: Increased superoxide production contributes to reduced vascular nitric oxide (NO) bioactivity and endothelial dysfunction in experimental models of diabetes. We characterized the sources and mechanisms underlying vascular superoxide production in human blood vessels from diabetic patients with coronary artery disease compared with nondiabetic patients. METHODS AND RESULTS: Vascular superoxide production was quantified in both saphenous veins and internal mammary arteries from 45 diabetic and 45 matched nondiabetic patients undergoing coronary artery bypass surgery. NAD(P)H-dependent oxidases were important sources of vascular superoxide in both diabetic and nondiabetic patients, but both the activity of this enzyme system and the levels of NAD(P)H oxidase protein subunits (p22phox, p67phox, and p47phox) were significantly increased in diabetic veins and arteries. In nondiabetic vessels, endothelial NO synthase produced NO that scavenged superoxide. However, in diabetic vessels, the endothelium was an additional net source of superoxide production because of dysfunctional endothelial NO synthase that was corrected by intracellular tetrahydrobiopterin supplementation. Furthermore, increased superoxide production in diabetes was abrogated by the protein kinase C inhibitor chelerythrine. CONCLUSIONS: These observations suggest important roles for NAD(P)H oxidases, endothelial NO synthase uncoupling, and protein kinase C signaling in mediating increased vascular superoxide production and endothelial dysfunction in human diabetes mellitus.