Remote monitoring (RM) is the newest function of cardiac implantable electronic devices (CIEDs). In our observational retrospective analysis, we aimed to assess whether telecardiology could be a safe alternative to routine outpatient examinations during the COVID-19 pandemic. The in- and outpatient visits, the number of acute cardiac decompensation episodes, the RM data from CIEDs, and general condition were examined via questionnaires (KCCQ, EQ-5D-5L). Regarding the enrolled 85 patients, the number of personal patient appearances was significantly lower in the year following the pandemic outbreak compared to the previous year (1.4 ± 1.4 and 1.9 ± 1.2, p = 0.0077). The number of acute decompensation events was five before and seven during lockdown (p = 0.6). Based on the RM data, there was no significant difference in heart failure (HF) markers (all related p > 0.05); only patient activity increased after restrictions were lifted compared to that before the lockdown (p = 0.03). During restrictions, patients reported increased anxiety and depression compared to their previous state (p < 0.001). There was no subjective change in the perception of HF symptoms (p = 0.7). Based on the subjective perception and CIED data, the quality of life of patients with CIED did not deteriorate during the pandemic, but their anxiety and depression intensified. Telecardiology may be a safe alternative to routine inpatient examination.

Out-of-hospital cardiac arrest (OHCA) represents a critical public health challenge, with poor survival. Our objective was to evaluate the association between extreme temperature events and OHCA incidence in Hungary, and to assess the potential influence of additional meteorological factors, including humidity and solar radiation. We conducted a national time-series analysis of 116,579 adult OHCA cases from November 1, 2018, to December 31, 2023. Using negative binomial regression with cluster-robust standard errors, we estimated associations between daily OHCA counts and extreme temperature events, controlling for day-of-week, seasonality, and long-term trends. “Added-effect” models isolated risk attributable to sustained events while controlling for underlying non-linear temperature-health relationships through natural cubic splines. Distributed lag non-linear models (DLNM) characterized exposure-lag-response patterns over 21 days. The temperature-OHCA relationship exhibited a characteristic U-shape with minimum risk at 19.0 °C. Sustained cold spells (≥2 days with daily minimum temperature ≤−9.2 °C, 2nd percentile) were associated with the highest risk increase (IRR 1.189; 95 % CI: 1.089–1.299; p < 0.001). Sustained heatwaves (≥3 days with daily average temperature ≥27.1 °C, 95th percentile) also significantly increased risk (IRR 1.110; 95 % CI: 1.032–1.195; p = 0.005). Single severe cold days (minimum temperature <−10 °C) carried an IRR of 1.143 (95 % CI: 1.012–1.291; p = 0.031). DLNM analysis revealed distinct temporal patterns: heat effects were acute and transient (peak at days 2–4, resolved by day 7), while cold effects were delayed and persistent (emerging at day 3, sustained beyond 14 days). Prolonged extreme temperatures represent independent cardiovascular hazards beyond isolated daily exposures. The immediate impact of heat and the delayed, persistent effect of cold carry important implications for public health preparedness, emergency service planning, and the timing of clinical advisories.

ECMO has become a therapeutic modality for in- and out-of-hospital scenarios and is also suitable as a bridging therapy until further decisions and interventions can be made. Case report: A 27-year-old male patient with mechanical aortic valve prothesis had a sudden cardiac arrest (SCA). ROSC had been achieved after more than 60 min of CPR and eight DC shocks due to ventricular fibrillation (VF). The National Ambulance Service unit transported the patient to our clinic for further treatment. Due to the trauma and therapeutic INR, a CT scan was performed and ruled out bleeding. Echocardiography described severely decreased left ventricular function. Coronary angiography was negative. Due to the therapeutic refractory circulatory and respiratory failure against intensive care, VA-ECMO implantation was indicated. After four days of ECMO treatment, the patient’s circulation was stabilized without neurological deficit, and the functions of the end organs were normalized. Cardiac MRI showed no exact etiology behind SCA. ICD was implanted due to VF and SCA. The patient was discharged after 19 days of hospitalization. Conclusion: This case report points out that the early application of mechanical circulatory support could be an outcome-determinant therapeutic modality. Post-resuscitation care includes cardiorespiratory stabilization, treatment of reversible causes of malignant arrhythmia, and secondary prevention.

Basic life support (BLS) skills are crucial not only for healthcare workers but for all lay people as well. Timely recognition of out-of-hospital cardiac arrest (OHCA) and the initiation of BLS by bystanders before the arrival of healthcare personnel may improve survival. There are several methods of spreading BLS skills and improve BLS skill retention among lay people. One of these methods can be the education of adolescent school children. The introduction of mandatory BLS education in schools was very effective in some European countries to increase the rate of bystander BLS. The current study aims to investigate the efficacy of a BLS training and BLS curriculum among high school children in Hungary. Moreover, the investigators would like to optimise factors influencing skill retention in this first responder group and aim to compare two types of teaching methods: feedback given by the instructor or software-based feedback on the efficacy of chest compressions during the course. This study will be an interventional, assessor blinded, individually randomised parallel group trial recruiting 360 students. BLS skill retention will be assessed at the end of the course, two months after the training and six months after training. The current study will increase our knowledge on the methods educating BLS among high school children. The results will help us to create an effective BLS curriculum at schools. Trial registration: ClinicalTrials.gov: NCT06016153. Prospectively registered on 08/2023.

Out-of-hospital cardiac arrest (OHCA) outcomes often differ between urban and rural settings, but comprehensive nationwide data from Central-Eastern Europe using uniform data collection and modern confounding control remain limited. We investigated urban–rural disparities in OHCA outcomes in Hungary. We analysed 130,258 OHCA cases (2018–2023) from the Hungarian National Ambulance Service registry, classified as urban (70.1 %) or rural (29.9 %) using national administrative categories. The primary outcome was on-scene return of spontaneous circulation (ROSC). We performed univariable and multivariable logistic regression, propensity score matching (PSM) and continuous response-time modeling using natural cubic splines. The overall ROSC rate was 9.1 % (urban: 9.4 %, rural: 8.3 %, p < 0.001). After PSM, urban location remained significantly associated with higher survival (OR = 1.26, 95 % CI 1.20–1.32, p < 0.001). EMS response times were significantly longer in rural areas (median 14.9 vs 9.8 min, p < 0.001). Urban survival advantage was most pronounced in cases with shockable rhythms (OR = 1.57, 95 % CI 1.43–1.72), medical-witnessed arrests (OR = 1.31, 95 % CI 1.20–1.42), and response times ≤8 min (OR = 1.59, 95 % CI 1.44–1.76). Significant urban–rural disparities in OHCA on-scene ROSC persist even after accounting for patient and arrest characteristics. These findings highlight the need for targeted interventions to strengthen the Chain of Survival in rural communities.

Background: Early defibrillation improves outcomes in cardiac arrest, but the optimal defibrillation strategy and energy requirements remain debated. This study investigated whether arterial blood gas (ABG) parameters could predict optimal defibrillation energy requirements for achieving the highest first-shock success rates in an animal model. Our study focused on clinical scenarios where ABG measurements are readily available, such as ventricular tachycardia and ventricular fibrillation storms requiring multiple shock deliveries. Materials and Methods: In the experimental setting, ventricular fibrillation was induced by 50 Hz direct current (DC), and the defibrillation threshold (DFT) was determined using a stepwise defibrillation protocol. ABG parameters were measured before each defibrillation attempt, recording partial arterial pressure of carbon dioxide (PaCO₂) and oxygen (PaO₂), pH, hematocrit (Hct), sodium (Na⁺), potassium (K⁺), and bicarbonate (HCO₃⁻) levels. The relationships between ABG parameters and the DFT were analyzed for 15 subjects using classical data analysis techniques and machine learning (ML) algorithms. Multiple ML models were trained and tested to predict the higher energy needed for successful defibrillation based on the ABG parameters. Results: Statistically significant differences were found in Hct and Na⁺ levels between the two DFT categories, above 130 Joules (J) and below 40 J (p < 0.01). The DFT negatively correlated with PaO₂ and positively correlated with Hct and Na⁺. However, other ABG parameters did not show significant correlations with DFT. Using ML, we predicted cases requiring higher defibrillation E. Our best-performing model, the Extra Trees Classifier, achieved 83% overall accuracy, with 100% and 67% precision rates for higher and lower DFT categories, respectively. We validated the model using bootstrap resampling and 10-fold cross-validation, confirming consistent performance. We identified Hct, PaCO₂, and PaO₂ as significant contributors to model prediction based on the feature importance value. Conclusions: Modern data analysis techniques applied to ABG parameters may guide personalized defibrillation energy selection, particularly in controlled clinical environments such as catheterization laboratories and intensive care units where ABG measurements are readily available.