Amiodarone and amplitude spectral area of ventricular fibrillation in patients with out-of-hospital cardiac arrest

Background Ventricular fibrillation is the most common cause of out-of-hospital cardiac arrest (OHCA) and the use of antiarrhythmic drug therapy is usually recommended in addition to defibrillation. The role of the amplitude spectral area (AMSA) of ventricular fibrillation as a predictor of defibrillation efficacy has been established, while the existing data in favour of the use of amiodarone has been assessed with poor evidence and controversy. Purpose The aim of our study is to evaluate whether the administration of amiodarone during resuscitation could affect AMSA values. Materials All the OHCAs with a shockable presenting rhythm and attempted resuscitation which occurred from January 2015 to June 2019 in the province of Pavia were considered. Both the end-tidal CO2 (ETCO2) and AMSA values were calculated by retrospectively analyzing the data collected by the Corpuls 3 monitors/defibrillators (Corpuls, Kaufering, Germany) used in the territory and by considering a pre-shock interval of 2 seconds. Results Among a total of 3413 OHCAs, resuscitation was attempted in 2195 cases (64%), 377 (17%) had a shockable presenting rhythm and in 112 cases (3.4%) it was possible to obtain the values of ETCO2 and AMSA for a total of 391 shocks. Among these, 301 shocks (77%) were delivered to patients who received amiodarone during resuscitation. The success rate of each single shock was similar in the two groups but with an unfavorable trend for amiodarone (amiodarone 43.5% vs no amiodarone 54.4%, p=0.07). AMSA was significantly lower in patients treated with amiodarone (7.9 mV·Hz, IQR 5.4–12.2 vs 10.6 mV·Hz, IQR 7.1–14.1; p<0.001). According to a multivariate analysis, the administration of amiodarone and the time to shock were independent predictors of AMSA values. Lastly, on a sample of 124 shocks, homogeneous for age, sex, ETCO2, outcome of resuscitation and randomly matched, the AMSA of patients who received amiodarone was significantly lower (7.2 mV·Hz, IQR 7.2–11.7 vs 9.7 mV·Hz, IQR 6.7–12.5; p=0.02). Conclusions Our results indicate that amiodarone administration is associated with lower values of AMSA. Since higher AMSA values are known to be associated with a higher probability of shock rate success, this could help to better clarify the controversial role of amiodarone administration in patients with OHCA. FUNDunding Acknowledgement Type of funding sources: None.

Impact of genetic tests on survivors of paediatric sudden cardiac arrest

ObjectiveTo retrospectively investigate the clinical spectrum, genetic profiles and outcomes of survivors of paediatric sudden cardiac arrest (SCA).Design and patientsAll 66 patients (aged 1–20 years), with unexpected SCA or syncope related to ventricular tachycardia (VT)/fibrillation and who survived to discharge from a tertiary centre, were enrolled from 1995 to 2018. Of these, 30 with underlying diseases prior to the events were excluded. Whole-exome sequencing targeting 384 channelopathy and cardiomyopathy-related genes (composite panel) was conducted to identify the possible genetic variants/mutations.ResultsA total of 36 patients were enrolled. Male adolescents predominated (66.7%), and the median age at onset was 13.3 years. Events occurred most often during exercise and daily activities. The yield rate of the genetic test was 84.6% (22/26); 14 had pathogenic variants; and 8 had likely pathogenic variants. The most common diagnoses were long QT in nine (25%), catecholaminergic polymorphic VT in six patients (16.7%), but other long QT and cardiomyopathy genes were also detected in eight patients (30.7%). The 10-year transplantation-free survival rate was 87.8% and was better for those who received genetic tests initially at the disease onset. An implantable cardioverter–defibrillator was implanted in 55.6% of the patients, with an appropriate shock rate of 61.1%. The defibrillator shock rate was lower for those who received composite panel initially.ConclusionSurvivors of SCA in the paediatric population had favourable long-term outcomes aided by genetic test. A broad composite genetic panel brings extra diagnostic value in the investigation of ventricular fibrillation/sudden cardiac death.

Risk of Complications in Children With Type 1 Diabetes and Covid-19

Background: There is some data available in adults which suggests that Type 1 diabetes may be associated with higher risk with Covid-19 (1). Limited data has been available in pediatric Type 1 diabetes with Covid-19. Methods: We used TriNetX, with a large COVID-19 database, collecting real-time electronic medical records data. We compared children (0–18 years) who were diagnosed with Covid-19 with and without Type 1 diabetes. This database collected information from 54 health care organizations. Results: Mortality rate in children with Covid-19 and Type 1 diabetes was 0.618% (10/1618). Mortality rate in children with Covid-19 without Type 1 diabetes was 0.102% (257/251517). Relative risk of mortality for children with Covid-19 and Type 1 diabetes was 6.05 with a p value of < 0.0001. Endotracheal intubation rate in children with Covid-19 and Type 1 diabetes was 0.618% (10/1618). Endotracheal intubation rate in children with Covid-19 without Type 1 diabetes was 0.071% (178/251517). Relative risk of endotracheal intubation for children with Covid-19 and Type 1 diabetes was 8.73 with a p value of < 0.0001. Pneumonia rate in children with Covid-19 and Type 1 diabetes was 0.804% (13/1618). Pneumonia rate in children with Covid-19 without Type 1 diabetes was 0.562% (1414/251517). Relative risk of pneumonia for children with Covid-19 and Type 1 diabetes was 1.43 with a p value of < 0.1959. Septic shock rate in children with Covid-19 and Type 1 diabetes was 1.05% (17/1618). Septic shock rate in children with Covid-19 without Type 1 diabetes was 0.293% (737/251517). Relative risk of septic shock for children with Covid-19 and Type 1 diabetes was 3.59 with a p value of < 0.00001. Conclusion: Mortality rate, endotracheal and septic shock were increased in children with Type 1 diabetes and Covid-19 versus children with Covid-19 and no Type 1 diabetes. Further studies with larger sample size are needed to study complication rate of Covid-19 and Type 1 diabetes. References 1) Associations of type 1 and type 2 diabetes with COVID-19-related mortality in England: a whole-population study. Lancet Diabetes Endocrinol 2020 Oct;8(10):813–822. doi: 10.1016/S2213-8587(20)30272-2. Epub 2020 Aug 13.

Exercise-optimized programming after S-ICD implantation contributes to a lower risk of inappropriate shocks in the latest generation S-ICDs

Funding Acknowledgements Type of funding sources: None. Background Implantable cardioverter-defibrillator (ICD) therapy is associated with the risk of inappropriate shocks (IAS). IAS, defined as any shock on a different rhythm than VT or VF, cause psychological stress, decrease the quality of life and may provoke ventricular arrhythmias. In the subcutaneous ICD (S-ICD) the majority of IAS are caused by T-wave oversensing (TWOS), often during exercise. Exercise-optimized programming during an exercise ECG test (X-ECG) after implantation has shown to be successful in reducing IAS in patients known with TWOS. In recent years, new discrimination algorithms in the latest generation S-ICDs have significantly reduced the risk of TWOS. The benefit of performing an X-ECG in these latest generation S-ICDs to reduce IAS is unclear. Purpose We aim to describe the effect of exercise-optimized programming after S-ICD implantation on inappropriate shock rate in the latest generation S-ICDs. Methods In this retrospective multicenter study, data were collected from two experienced S-ICD hospitals in the Netherlands. All patients underwent an S-ICD implantation of second or third generation between February 2015 and December 2020. Patients younger than 21 years were excluded. Patients with an X-ECG after implantation were compared with patients without X-ECG after implantation. Total number of patients with IAS and cause of the first IAS were evaluated. Results In total, 262 patients were included in the X-ECG group and 61 in the no X-ECG group. The median follow-up time was 22 months in the X-ECG group (IQR 9-33) and 23 months in the no X-ECG group (IQR 12-33, P = 0.9). Mean age was 51 ± 15 years and 61 ± 15 years respectively (P< 0.001). Primary prevention indication was similar in both groups (56% for the X-ECG group versus 49% for the no X-ECG group, P = 0.4). A total of 8 patients (3.1%) experienced IAS in the X-ECG group; 3 first shocks (1.15%) were due to TWOS, 2 (0.8%) were given on a SVT and 3 (1.15%) on other non-cardiac activity. In the no X-ECG group, 6 patients (9.8%) experienced IAS; 1 first shock (1.6%) was due to TWOS, 4 (6.6%) were given on a SVT and 1 (1.6%) on other non-cardiac activity. Patients with an X-ECG had a significantly lower risk of IAS compared to patients in the no X-ECG group (hazard ratio 0.32; 95% CI 0.1 to 0.9; P = 0.027). The Kaplan-Meier estimate of IAS-free survival for the X-ECG group was 61 months (95% CI 59 to 62) and 50 months (95% CI 46 to 55) for the no X-ECG group. Results are shown in the figure. Conclusion This study shows that, in the latest generation S-ICDs, exercise-optimized programming after S-ICD implantation results in a significantly lower risk of IAS in adults. Patients with an X-ECG after S-ICD implantation were younger, which may have affected the outcome. Further prospective data with more equal groups is necessary. Until then, we recommend considering exercise testing after S-ICD implantation in the latest generation S-ICDs. Abstract Figure.

Identification of Key Lines for Multi-Photovoltaic Power System Based on Improved PageRank Algorithm

In order to accurately identify the key lines in the photovoltaic (PV) grid-connected system, an identification method based on the improved PageRank algorithm is proposed. Firstly, the correlation matrix reflecting the electrical characteristics of the system is constructed using the line current-carrying rate, line breaking power flow transfer rate and line coupling rate, to replace the original network topology matrix. Secondly, through the entropy method, a comprehensive evaluation index based on electrical betweenness, load deviation rate and voltage shock rate is constructed to improve the distribution of the initial PageRank (PR) value of the PV grid-connected system. To study the changes’ impact of PVs active power outputs on the identification results of key lines in the Multi-PV power system, the HGWO-SVM (Hybrid Grey Wolves Optimized Support Vector Machine) algorithm was used to obtain the PVs daily outputs prediction curves and obtain fixed outputs of PVs at different periods, so as to study the impact of the variation of PV daily output on the key line identification. Taking the IEEE 39-node system containing multi-PV as an example, the identification results show that the improved PageRank algorithm is superior to the original method in line identification accuracy. The HGWO-SVM algorithm by adaptively modifying the cross operator and mutation operator also has a certain improvement in prediction accuracy. The changes of PVs daily outputs have different degree of influence on the line criticality (namely final PR value) during periods of high light intensity and other periods of light intensity.

Non-surgical treatment of urinary stone

Some patients with urinary stones can be managed non-surgically through observation, medication, or extracorporeal shockwave lithotripsy (ESWL). Symptomatic urinary stones can initially be treated conservatively using analgesics and hydration. When uncontrolled pain or infection is present, immediate diversion via either percutaneous nephrostomy or ureteral stenting may be necessary. Medical expulsive therapy utilizing alpha-blocker may benefit a selected group of patients with stones larger than 5 mm. Oral or percutaneous chemolysis is a well-established non-invasive option with a reasonable success rate for patients with a certain component such as uric acid. When medical treatment is applied, its unintended side effects should be considered and routinely monitored. Extracorporeal shockwave lithotripsy is a highly effective and safe modality in treating urinary stones when adequately indicated. In addition to the size and location of the stone, information obtained from non-enhanced computed tomography such as stone density, stone heterogenicity index, and stone-to-skin distance can be applied to predict the possibility of ESWL failure. Modifications in shock wave delivery by altering shock rate and voltage can improve shock wave efficacy. Urinary stones can be managed effectively and safely using non-surgical approaches.

The Wearable Cardioverter/ Defibrillator: retrospective analysis of efficacy, safety and adherence

Background The use of the Wearable Cardioverter Defibrillator (WCD) is recommended in national, European and American guidelines. However, there are almost exclusively data from the manufacturer's own data network. Independent data on the experience with the WCD are rare. Objective The aim of the retrospective study from one cardiologic department was to record efficiency, safety and compliance of the WCD. Patients and methods The study included all patients, to whom a WCD was described between 1.11.2010 and 1.5.2018 at one cardiologic department. Clinical data were obtained from the patients' records and the data about the WCD from the information network of the manufacturer. Results This study enrolled 66 patients, 51 males (77%) and 15 females (23%). The median age was 55 years (IQR: 45–63). They suffered from ischemic cardiomyopathy (n=33; 49%), dilated cardiomyopathy (n=12; 18%), myocarditis (n=7; 11%), explantation of an implantable cardioverter/defibrillator (ICD; n=5; 8%) and other indications (n=6; 9%). The median wearing time of the WCD was 73 days (interquartile range-IQR: 39–126), with median daily use of 22.91 h (IQR: 19.58–23.61). Among 38 patients with LVEF ≤35%, LVEF improved to ≥35% in 19 patients (50%) during WCD therapy. Over 1600 times the WCD detected a VT falsely. Four patients (8%) suffered from 212 non-sustained VT. One patient was successfully shocked because of ventricular fibrillation (appropriate shock rate: 1.5%). There were no inappropriate shocks. All patients, who wore the WCD, survived and one patient died when he did not wear the WCD. At the end of therapy 32 patients (48%) received an ICD. In terms of wearing time and events (shocks, arrhythmias, artifacts) there were no significant differences between patients receiving ICD and those who did not receive an ICD. Patients who received an ICD had a significantly lower LVEF after 3 months than patients who did not receive an ICD. Conclusion Our data confirm, that the WCD is safe and that the patients, who wear a WCD, have a high adherence. More than half of the patients with reduced LVEF improved their systolic function during WCD therapy, thus obviating the need for ICD implantation. Questions about the effectiveness of the detection algorithm remained open. Funding Acknowledgement Type of funding source: None

917Appropriate shocks in WCD patients - Results from the Austrian WCD registry

Background The wearable cardioverter-defibrillator (WCD) is a temporary treatment option for patients at high risk for sudden cardiac death (SCD) and/or for patients in whom implantation of a cardioverter defibrillator (ICD) is temporarily not possible. Purpose To investigate incidence and predictors of appropriate WCD shocks. Methods We performed a retrospective analysis of all patients with appropriate shocks delivered by a WCD in the cohort of the Austrian WCD registry between 2010 and 2018. Within this dataset, we identified predictors within the baseline characteristics, the indication for the WCD and preceding alarms automatically recorded by the WCD. Results: Baseline Within 879 registered in the Austrian WCD registry, 31 patients (3,5%) received appropriate WCD shocks due to ventricular tachycardia (VT) or ventricular fibrillation (VF). Compared to the total cohort, shocked patients were elder (mean age 67 ± 14 vs. 60 ± 14 years, p = 0,001) and the percentage of female patients was lower (11% vs. 21%, p = 0,262). The mean baseline LVEF at prescription was 33 ± 15% in the population with appropriate shocks compared to 32 ± 14% in the all-over cohort (p = ns). In the Austrian WCD population, 378/879 patients had a WCD due to secondary prevention. Within this cohort 5,6% (21/378) had shocks for VT/VF again, compared to 10/501 (2%) shocked patients in the primary prevention cohort. 31/879 (3.5%) patients received 57 appropriate shocks, the per patient shock rate was 2 [1;5]. These shocks were induced by 25 ventricular tachycardia and 26 times ventricular fibrillation. The octagenarians with 11% (7/34) shocked patients, showed a significant higher likelihood to receive shocks (p = 0,008) as well as the cohort of secondary preventive prescribed WCD-patients (p = 0,007). There were more shocks in patients, when prescribed with a WCD due to ICD associated infections (p = 0,001), when used as a bridge to ICD (p = 0,042) and in patients with ongoing risk stratification (p = 0,009). Looking through the automatically recorded alarms preceding a WCD shock, shocked patients experienced significantly more often non sustained VTs (p < 0,0005) and sustained VTs that were haemodynamically tolerated and did not require a treatment (p < 0,0005). Conclusion The WCD is effective in preventing SCD and an important risk stratification tool. We identified advanced age, patients with either already confirmed indication for ICD implantation (either temporary contraindication for implantation or temporary explantation) or risk stratification of an unclear cardiomyopathy, the cohort of secondary prevention and preceding nsVTs and stable VTs as predictors for appropriate WCD therapies.

Blunt Cardiac Injury: A Single-Center 15-Year Experience

In recent years, the incidence of blunt cardiac injury (BCI) has increased rapidly and is an important cause of death in trauma patients. This study aimed to explore early diagnosis and therapy to increase survival. All patients with BCI during the past 15 years were analyzed retrospectively regarding the mechanism of injury, diagnostic and therapeutic methods, and outcome. The patients were divided into two groups according to the needs of their condition—nonoperative (Group A) and operative (Group B). Comparisons of the groups were performed. A total of 348 patients with BCI accounted for 18.3 per cent of 1903 patients with blunt thoracic injury. The main cause of injury was traffic accidents, with an incidence of 48.3 per cent. In Group A (n = 305), most patients sustained myocardial contusion, and the mortality was 6.9 per cent. In Group B (n = 43), including those with cardiac rupture and pericardial hernia, the mortality was 32.6 per cent. Comparisons of the groups regarding the shock rate and mortality were significant ( P < 0.01). Deaths directly resulting from BCI in Group B were greater than those in Group A ( P < 0.05). In all 348 patients, the mortality rate was 10.1 per cent. When facing a patient with blunt thoracic injury, a high index of suspicion for BCI must be maintained. To manage myocardial contusion, it is necessary to protect the heart, alleviate edema of the myocardium, and control arrhythmia with drugs. To deal with those requiring operation, early recognition and expeditious thoracotomy are essential.