Assessing cardiac resynchronization therapy response in heart failure patients: a comparative analysis of efficacy and outcomes between transvenous and epicardial leads.

Cardiac resynchronization therapy (CRT) is an effective treatment for selected heart failure (HF) patients. Although transvenous implantation is the standard method, it is not feasible in some patients, so the epicardial lead emerges as an alternative. We aim to compare CRT response, procedure-related complications, and the occurrence of clinical outcomes between patients with transvenous and epicardial leads. In a single-center retrospective study, we enrolled consecutive HF patients submitted to CRT implantation with a defibrillator between 2013 and 2022. Clinical response was defined as an improvement of at least one of the New York Heart Association classes with no occurrence of cardiovascular death or HF hospitalization in the first year of follow-up. Echocardiographic response was attained with an increase in left ventricular ejection fraction 10% or a reduction of left ventricular end-diastolic volume >15% at 6-12 months after CRT implantation. Major adverse cardiovascular events (MACE) (cardiovascular mortality and HF hospitalization) and all-cause mortality were evaluated. From a total of 149 patients, 38% (n=57) received an epicardial lead. Clinical (63% versus 60%, p=0.679) and echocardiographic (63% versus 60%, p=0.679) responses were similar between the transvenous and epicardial groups. Patients in the transvenous group had a shorter hospital stay (2 versus 7 days, p<0.001). Procedure-related complications were comparable between groups (24% versus 28%, p=0.572), but left ventricular lead-related complications were more frequent in the transvenous group (14% versus 2%). During a median follow-up of 4.7 years, the rate of MACE was 30% (n=44), with no differences in both groups (p=0.591), neither regarding HF hospitalization (p=0.917) nor cardiovascular mortality (p=0.060). Nevertheless, the epicardial group had a higher rate of all-cause mortality (35% versus 20%, p=0.005), the majority occurring during long-term follow-up (>12 months), with no deaths in the postoperative period. Considering the comparable rates of CRT response, procedure-related complications, and MACE between groups, we conclude that epicardial lead is a feasible alternative for CRT when transvenous lead implantation is not possible. The occurrence of a higher number of all-cause deaths in epicardial patients in the long-term follow-up was mainly due to infectious complications (unrelated to the lead) and the progression of oncological/chronic diseases.

Assessment of Cardiorespiratory and Metabolic Contributions in an Extreme Intensity CrossFit® Benchmark Workout.

Our purpose was to characterize the oxygen uptake kinetics (VO2), energy systems contributions and total energy expenditure during a CrossFit® benchmark workout performed in the extreme intensity domain. Fourteen highly trained male CrossFitters, aged 28.3 ± 5.4 years, with height 177.8 ± 9.4 cm, body mass 87.9 ± 10.5 kg and 5.6 ± 1.8 years of training experience, performed the Isabel workout at maximal exertion. Cardiorespiratory variables were measured at baseline, during exercise and the recovery period, with blood lactate and glucose concentrations, including the ratings of perceived exertion, measured pre- and post-workout. The Isabel workout was 117 ± 10 s in duration and the VO2 peak was 47.2 ± 4.7 mL·kg-1·min-1, the primary component amplitude was 42.0 ± 6.0 mL·kg-1·min-1, the time delay was 4.3 ± 2.2 s and the time constant was 14.2 ± 6.0 s. The accumulated VO2 (0.6 ± 0.1 vs. 4.8 ± 1.0 L·min-1) value post-workout increased substantially when compared to baseline. Oxidative phosphorylation (40%), glycolytic (45%) and phosphagen (15%) pathways contributed to the 245 ± 25 kJ total energy expenditure. Despite the short ~2 min duration of the Isabel workout, the oxygen-dependent and oxygen-independent metabolism energy contributions to the total metabolic energy release were similar. The CrossFit® Isabel requires maximal effort and the pattern of physiological demands identifies this as a highly intensive and effective workout for developing fitness and conditioning for sports.

Cardioneuroablation for severe neurocardiogenic syncope.

INTRODUCTION AND OBJECTIVES: Cardioneuroablation (CNA), a technique based on radiofrequency ablation of cardiac vagal ganglia, was developed to treat recurrent vasovagal syncope (VVS) with a predominant cardioinhibitory component, as an alternative to pacemaker implantation. The aim of our study was to evaluate the safety and success rate of CNA guided by extracardiac vagal stimulation in patients with highly symptomatic cardioinhibitory VVS. METHODS: Prospective study of patients who underwent anatomically guided CNA at two cardiology centers. All patients had a history of recurrent syncope with a predominant cardioinhibitory component and refractory to conventional measures. Acute success was determined by the absence or significant reduction of cardiac parasympathetic response to extracardiac vagal stimulation. The primary endpoint was the recurrence of syncope during follow-up. RESULTS: In total, 19 patients (13 males; mean age 37.8±12.9 years) were included. Ablation was acutely successful in all patients. One patient had a convulsive episode after the procedure, which was deemed unrelated to the ablation, requiring admission to intensive care but without sequelae. No other complications occurred. At a mean follow-up of 21.0±13.2 months (range 3-42 months), 17 patients remained free of syncope. The remaining two patients had recurrence of syncope and, despite undergoing a new ablation procedure, required pacemaker implantation during follow-up. CONCLUSION: Cardioneuroablation, confirmed by extracardiac vagal stimulation, appears to be an effective and safe treatment option for highly symptomatic patients with refractory VVS with a predominant cardioinhibitory component, providing a new potential approach as an alternative to pacemaker implantation.

Physical Fitness Profile of High-Level Female Portuguese Handball Players.

We characterized the physical and physiological profiles of high-level female Portuguese handball players and examined the relationships between their anthropometric characteristics, general motor performance and cardiopulmonary fitness. Twenty-four high-level female handball players with an average age of 23.6 ± 5.5 years, height of 173.6 ± 5.1 cm and body mass of 72.6 ± 9.1 kg volunteered to participate. A Pearson correlation test was used to assess the relationship between variables. Direct relationships were observed between the players' height and arm span (r = 0.741), as well as between their squat jump and countermovement jump performances with regard to body mass (r = 0.448 and 0.496, respectively). The 9 m jump shot has a large relationship with the 7 m standing throw (r = 0.786) and between left hand dynamometry and body mass index (r = 0.595). The 30 m sprint has a relationship with the 7 m standing throw (r = -0.526) and the 9 m jump throw (r = -0.551). Oxygen uptake has a relationship with the players' height (r = -0.482) and time limit (r = 0.513), while the fitness index has a relation to the players' height (r = -0.488) and arm span (r = -0.422). Our results should be considered when using physical testing to plan optimal physical training regimens in elite team handball.

The brain-fat connection.

Type 2 innate lymphoid cells shape metabolism through a brain-body circuit.

Effects of Wearing a 50% Lower Jaw Advancement Splint on Biophysical and Perceptual Responses at Low to Severe Running Intensities.

Acute ergogenic effects of wearing occlusal splints have been reported for aerobic and anaerobic exercises, but the literature centered on performance improvement by using jaw repositioning splints is scarce. We aimed to analyze the effect of wearing a 50% lower jaw advancement splint on biophysical and perceptual responses at low to severe running intensities. Sixteen middle- and long-distance runners performed twice a 7 × 800 m intermittent running protocol (with 1 km·h-1 increments and 30 s rest periods) in an outdoor track field using two lower intraoral splints (a placebo and a lower jaw advancer). These devices were custom manufactured for each participant and a randomized and repeated measure design was used to compare conditions. No differences between placebo and lower jaw advancer were found (e.g., 52.1 ± 9.9 vs. 53.9 ± 10.7 mL·kg-1·min-1 of oxygen uptake, 3.30 ± 0.44 vs. 3.29 ± 0.43 m of stride length and 16 ± 3 vs. 16 ± 2 Borg scores), but small effects were sometimes observed (e.g., 109.2 ± 22.5 vs. 112.7 ± 25.2 L·min-1 of ventilation, ES = -0.42). Therefore, this jaw advancement splint had no substantial ergogenic effect on biophysical and perceptual responses when running at different intensities.

Case Study: A Jaw-Protruding Dental Splint Improves Running Physiology and Kinematics.

Wearing an intraoral jaw-protruding splint could enhance respiratory function in clinical settings and eventually exercise performance. PURPOSE: The authors studied the acute effect of wearing a lower-jaw-forwarding splint at different protruding percentages (30% and 50%) across a wide range of running exercise intensities. METHODS: A case study was undertaken with a highly trained and experienced 27-year-old female triathlete. She performed the same incremental intermittent treadmill running protocol on 3 occasions wearing 3 different intraoral devices (30% and 50% maximum range and a control device) to assess running physiological and kinematic variables. RESULTS: Both the 30% and 50% protruding splints decreased oxygen uptake and carbon dioxide production (by 4%-12% and 1%-10%, respectively) and increased ventilation and respiratory frequency (by 7%-12% and 5%-16%, respectively) along the studied running intensities. Exercise energy expenditure (approximately 1%-14%) and cost (7.8, 7.4, and 8.0 J·kg-1·m-1 for 30%, 50%, and placebo devices, respectively) were also decreased when using the jaw-protruding splints. The triathlete's lower limbs' running pattern changed by wearing the forwarding splints, decreasing the contact time and stride length by approximately 4% and increasing the stride rate by approximately 4%. CONCLUSIONS: Wearing a jaw-protruding splint can have a positive biophysical effect on running-performance-related parameters.

Machine Learning Approach to Model Physical Fatigue during Incremental Exercise among Firefighters.

Physical fatigue is a serious threat to the health and safety of firefighters. Its effects include decreased cognitive abilities and a heightened risk of accidents. Subjective scales and, recently, on-body sensors have been used to monitor physical fatigue among firefighters and safety-sensitive professionals. Considering the capabilities (e.g., noninvasiveness and continuous monitoring) and limitations (e.g., assessed fatiguing tasks and models validation procedures) of current approaches, this study aimed to develop a physical fatigue prediction model combining cardiorespiratory and thermoregulatory measures and machine learning algorithms within a firefighters' sample. Sensory data from heart rate, breathing rate and core temperature were recorded from 24 participants during an incremental running protocol. Various supervised machine learning algorithms were examined using 21 features extracted from the physiological variables and participants' characteristics to estimate four physical fatigue conditions: low, moderate, heavy and severe. Results showed that the XGBoosted Trees algorithm achieved the best outcomes with an average accuracy of 82% and accuracies of 93% and 86% for recognising the low and severe levels. Furthermore, this study evaluated different methods to assess the models' performance, concluding that the group cross-validation method presents the most practical results. Overall, this study highlights the advantages of using multiple physiological measures for enhancing physical fatigue modelling. It proposes a promising health and safety management tool and lays the foundation for future studies in field conditions.

Perimyocarditis Following COVID-19 Vaccination.

A 39-year-old male was admitted in the emergency room with chest pain. He had been given the second dose of Pfizer-BioNTech COVID-19 vaccine 3 days before. The patient denied taking any other medication beyond the usual. He didn't feel sick in the previous days/weeks. Laboratory studies revealed elevated serum levels of troponin and C-reactive protein. An autoantibody screen and a serologic panel to detect common viruses were negative. A cardiac MRI showed myocardial edema/inflammation and confirmed the diagnosis of perimyocarditis which was considered to be a consequence of COVID-19 vaccination. Physicians should be aware of the possibility of cardiovascular complications after COVID-19 vaccination.

Neuro-mesenchymal units control ILC2 and obesity via a brain-adipose circuit.

Signals from sympathetic neurons and immune cells regulate adipocytes and thereby contribute to fat tissue biology. Interactions between the nervous and immune systems have recently emerged as important regulators of host defence and inflammation1-4. Nevertheless, it is unclear whether neuronal and immune cells co-operate in brain-body axes to orchestrate metabolism and obesity. Here we describe a neuro-mesenchymal unit that controls group 2 innate lymphoid cells (ILC2s), adipose tissue physiology, metabolism and obesity via a brain-adipose circuit. We found that sympathetic nerve terminals act on neighbouring adipose mesenchymal cells via the ß2-adrenergic receptor to control the expression of glial-derived neurotrophic factor (GDNF) and the activity of ILC2s in gonadal fat. Accordingly, ILC2-autonomous manipulation of the GDNF receptor machinery led to alterations in ILC2 function, energy expenditure, insulin resistance and propensity to obesity. Retrograde tracing and chemical, surgical and chemogenetic manipulations identified a sympathetic aorticorenal circuit that modulates ILC2s in gonadal fat and connects to higher-order brain areas, including the paraventricular nucleus of the hypothalamus. Our results identify a neuro-mesenchymal unit that translates cues from long-range neuronal circuitry into adipose-resident ILC2 function, thereby shaping host metabolism and obesity.

Brugada syndrome: Eligibility for subcutaneous implantable cardioverter-defibrillator after exercise stress test.

INTRODUCTION: Brugada syndrome (BrS) is a channelopathy associated with ventricular arrhythmias and sudden cardiac death. In patients at high risk of sudden death, an implantable cardioverter-defibrillator is indicated. Subcutaneous implantable cardioverter-defibrillators (S-ICDs) are an alternative to transvenous systems, with reduced risk of infection and complications associated with system extraction or explantation. OBJECTIVE: To test electrocardiographic eligibility for S-ICD placement after exercise stress testing (EST) in patients with BrS. METHODS: The sample included 35 consecutive patients with BrS. Electrocardiographic eligibility was assessed using the Boston Scientific model 2889 EMBLEM™ S-ICD automated screening tool, in four phases: decubitus and orthostatism, and before and after EST. Those who had at least one acceptable vector in the four measurements were considered eligible. RESULTS: In this study, 71.4% of patients were male and mean age was 53.86±12 years. In screening prior to EST, 14.3% of patients (n=5) were not eligible for an S-ICD. There was a statistically significant association between ineligibility and presence of complete right bundle branch block and history of syncope. After EST, 16.7% of initially eligible patients no longer had eligible vectors (n=5). CONCLUSION: In this study, 16.7% of patients previously eligible for an S-ICD were no longer eligible after EST. This result demonstrates the importance of screening after EST in all patients with BrS and with indication for an S-ICD, and may influence decisions concerning which ICD to implant or whether to institute pharmacological measures that avoid inappropriate therapies.