Shock Delivery Research Articles

Time to change the times? Time of recurrence of ventricular fibrillation during OHCA

Aim of the studyFor out-of-hospital-cardiac-arrest (OHCA) due to ventricular fibrillation (VF) guidelines recommend early defibrillation followed by chest compressions for two minutes before analyzing shock success. If rhythm analysis reveals VF again, it is obscure whether VF persisted or reoccurred within the two-minutes-cycle of chest compressions after successful defibrillation. We investigated the time of VF-recurrence in OHCA. MethodsWe examined all cases of OHCA presenting with initial VF rhythm at arrival of ALS-ambulance (Marburg-Biedenkopf-County, 246.648 inhabitants) from January 2014 to March 2018. Three independent investigators analyzed corpuls3® ECG-recordings. We included ECG-data from CPR-beginning until four minutes after the third shock. VF termination was defined as the absence of a VF-waveform within 5 s of shock delivery. VF recurrence was defined as the presence of a VF-waveform in the interval 5 s post shock delivery. ResultsWe included 185 shocks in 82 patients. 74.1% (n = 137) of all shocks terminated VF, but VF recurred in 81% (n = 111). The median (IQR) time of VF-recurrences was 27 s (13.5 s/80.5 s) after shock. 51.4% (n = 57) of VF-recurrence occurred 5–30 s after shock, 13.5% (n = 15) VF-recurrence occurred 31−60 s after shock, 21.6% (n = 24) of VF-recurrence occurred 61–120 s after shock, 13.5% (n = 15) of VF-recurrence occurred 121–240 s after shock. ConclusionsAlthough VF was terminated by defibrillation in 74.1%, VF recurred in 81% subsequent to the chest compression interval. Thus, VF reappears frequently and early. It is unclear to which extend chest compressions influence VF-relapse. Further studies need to re-evaluate the algorithm, timing of antiarrhythmic therapy or novel defibrillation strategies to minimize refibrillation during shockable OHCA.

The unmet needs of sudden cardiac death. The role of the wearable cardioverter defibrillator when the risk is transient or uncertain

Sudden cardiac death is defined as a natural death due to termination of cardiac activity associated with loss of consciousness, spontaneous breathing and circulation. Nowadays, the prevention of sudden cardiac death represents a major issue and many areas of uncertainty are not met by current evidences. Among those, reliable tools for risk stratification are still lacking, as well as solution for patients in which the risk of sudden cardiac death is due to a transient or correctable condition.The concept of the wearable cardioverter defibrillator is based on a potential solution for such grey areas. It merges long-term monitoring capabilities, shockable rhythm discrimination and shock delivery without the need for bystander assistance or invasive procedures. The present review aims to summarize current problems in dealing with this insidious condition, and to discuss potential options for patients in whom sudden cardiac death could be prevented more safely and cost-effectively.

PREVALENCE AND CHARACTERISTICS OF HYPERTHYROIDISM AND ITS ASSOCIATION WITH CARDIAC MANIFESTATIONS IN US SARCOIDOSIS PATIENTS

SESSION TITLE: Diffuse Lung Disease Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: We aimed to determine the prevalence rate and clinical characteristics of hyperthyroidism and investigate its association with cardiac manifestations in patients with sarcoidosis METHODS: We conducted a national registry-based study investigating 3,836 respondents to the Sarcoidosis Advanced Registry for Cures Questionnaire in the period between June 2014 and August 2019. This registry is generated from a web-based questionnaire that is self-reported by sarcoidosis patients and provides data related to demographics, diagnostics, sarcoidosis manifestations and treatment. We compared sarcoidosis patients with and without hyperthyroidism. We used multivariate logistic regression analysis adjusted for gender, race, age at time of sarcoidosis diagnosis and comorbidities (cancer, diabetes mellitus, obesity, hypertension and sleep apnea) to study the association between hyperthyroidism and different cardiac manifestations in patients with sarcoidosis. RESULTS: Three-percent of US sarcoidosis patients self-reported having hyperthyroidism and were generally middle-aged Caucasian women. When compared to patients with no hyperthyroidism, patients with hyperthyroidism had more sarcoidosis related comorbidities (59% vs 43%, p=0.001) and more steroids-related comorbidities (56% vs 44%, p=0.01) but there was no difference in the sarcoidosis-specific treatments they received including corticosteroids. Hyperthyroidism patients more frequently reported sarcoidosis involvement of the heart (18.4% vs 10.1%, p=0.023), muscles (10.5% vs 6.4%, p=0.029), sinuses (12.3% vs 6.7%, p=0.026) and the gastrointestinal system (6.1% vs 4.9%, p=0.032). Cardiac manifestations that were more frequently reported in hyperthyroidism patients included atrial arrhythmias (11.3% vs 6.3%, p=0.046), ventricular arrhythmias (17.2% vs 7.5%, p<0.001), congestive heart failure (10.4% vs 5%, p=0.017) and heart block (9.4% vs 4.7%, p=0.036). There was no difference in placement of pacemakers or implantable cardioverter defibrillator (ICD) between the two groups. However, the hyperthyroidism patients reported ICD shock delivery more frequently (5.3% vs 2.2%, p=0.030). On multivariate logistic regression analysis adjusting for gender, race, age, cancer history, diabetes mellitus, obesity, hypertension and sleep apnea, hyperthyroidism patients were more likely to have ICD or pacemaker placed (aOR=1.89, 95% CI 1.02-3.51), heart block (aOR=2.20, 95% CI 1.05-4.63) and ventricular arrhythmias (aOR=2.52, 95% CI 1.42-4.46). CONCLUSIONS: Hyperthyroidism is common in patients with sarcoidosis and is potentially associated with different cardiac manifestations including cardiac arrhythmias. CLINICAL IMPLICATIONS: We suggest considering routine screening for hyperthyroidism in sarcoidosis patients especially with cardiac involvement. Further studies are needed to investigate the impact of identifying and treating hyperthyroidism in sarcoidosis patients. DISCLOSURES: No relevant relationships by Tamara Al-Hakim, source=Web Response No relevant relationships by Bashar Alzghoul, source=Web Response Own stock relationship with American airline, United Airlines and Delta Airlines Please note: $1001 - $5000 Added 06/01/2020 by Bara Alzghoul, source=Web Response, value=Own stock No relevant relationships by Farah Amer, source=Web Response My spouse/partner as a Own stock relationship with AMerican airlines, united airlines and delta airlines Please note: $1001 - $5000 Added 06/01/2020 by Sarah Ghaith, source=Web Response, value=Own stock No relevant relationships by Diana Gomez Manjarres, source=Web Response No relevant relationships by Johnny Jaber, source=Web Response No relevant relationships by Saminder Kalra, source=Web Response No relevant relationships by Divya Patel, source=Web Response No relevant relationships by Noopur Singh, source=Web Response

Long-Term Characterization of Hippocampal Remapping during Contextual Fear Acquisition and Extinction.

Hippocampal CA1 place cell spatial maps are known to alter their firing properties in response to contextual fear conditioning, a process called "remapping." In the present study, we use chronic calcium imaging to examine remapping during fear retrieval and extinction of an inhibitory avoidance task in mice of both sexes over an extended period of time and with thousands of neurons. We demonstrate that hippocampal ensembles encode space at a finer scale following fear memory acquisition. This effect is strongest near the shock grid. We also characterize the long-term effects of shock on place cell ensemble stability, demonstrating that shock delivery induces several days of high fear and low between-session place field stability, followed by a new, stable spatial representation that appears after fear extinction. Finally, we identify a novel group of CA1 neurons that robustly encode freeze behavior independently from spatial location. Thus, following fear acquisition, hippocampal CA1 place cells sharpen their spatial tuning and dynamically change spatial encoding stability throughout fear learning and extinction.SIGNIFICANCE STATEMENT The hippocampus contains place cells that encode an animal's location. This spatial code updates, or remaps, in response to environmental change. It is known that contextual fear can induce such remapping; in the present study, we use chronic calcium imaging to examine inhibitory avoidance-induced remapping over an extended period of time and with thousands of neurons and demonstrate that hippocampal ensembles encode space at a finer scale following electric shock, an effect which is enhanced by threat proximity. We also identify a novel group of freeze behavior-activated neurons. These results suggest that, more than merely shuffling their spatial code following threat exposure, place cells enhance their spatial coding with the possible benefit of improved threat localization.

Insights on arrhythmia termination and type 2 breaks after ICD therapy delivery.

Introduction of anti-tachycardia pacing (ATP) therapy and longer detection intervals delivery have allowed to safely reduce unnecessary shocks, improving survival and quality of life in implantable cardioverter defibrillator (ICD) patients. However, there are still outstanding issues, especially regarding the mode of arrhythmias termination after ATP or shock delivery. Regardless of ICD therapy efficacy, the arrhythmia interruption does not always occur abruptly, indeed both nonsustained tachy- or bradyarrhythmias have been described after ICD therapy delivery, being the former classified as type 2 interruption. Several physiopathological mechanisms have been suggested to be responsible for this phenomenon. Our aim is to review current data on postshock and post-ATP arrhythmias and to give insights on their possible mechanisms.

Different Manifestations in Familial Isolated Left Ventricular Non-compaction: Two Case Reports and Literature Review

Left ventricular non-compaction (LVNC) is a form of cardiomyopathy characterized by prominent trabeculae and deep intertrabecular recesses which form a distinct “non-compacted” layer in the myocardium. It results from intrauterine arrest of the compaction process of the left ventricular myocardium. Clinical manifestations vary from asymptomatic to heart failure (HF), arrhythmias, or thromboembolic events. We present a case of mother and son diagnosed with isolated LVNC (ILVNC). A 4-years-old male patient, diagnosed at 3 months with ILVNC, and NYHA functional class IV HF, was admitted to the Emergency Institute for Cardiovascular Diseases and Transplantation of Targu Mures, Romania, for cardiologic reevaluation, and diagnosis confirmation. ILVNC was confirmed using echocardiography, revealing a non-compaction to compaction (NC/C) ratio of > 2.7. His evolution was stationary until the age of 8 years, when severe pneumonia caused hemodynamic decompensation, and he was listed for heart transplantation (HT). The patient underwent HT at the age of 11 years with favorable postoperative outcome. Meanwhile, a 22-years-old female patient, mother of the aforementioned patient, was also admitted to our institute due to severe fatigue, dyspnea, and recurrent palpitations with multiple implantable cardioverter defibrillator (ICD) shock delivery. Extensive medical history revealed that a presumptive ILVNC diagnosis was established when she was 11 years old. She was asymptomatic until 18 years old, when 3 months post-partum, she developed NYHA functional class III HF, and subsequently underwent ICD implantation. Her diagnosis was confirmed using multi-detector computed tomography angiography, which revealed a NC/C ratio of > 3.3. ICD adjustments were carried out with a favorable evolution under chronic drug therapy. The last evaluation, at 27 years old, revealed that she was in NYHA functional class II HF. In conclusion, ILVNC, even when familial, can present different clinical pictures and therefore requires different medical approaches.

Duration and clinical features of cardiac arrest predict early severe cerebral edema

BackgroundSevere brain edema appears early after cardiopulmonary resuscitation (CPR) in a subset of patients and portends a poor prognosis. We tested whether clinical features of patients or resuscitation during out-of-hospital cardiac arrest (OHCA) are associated with early, severe cerebral edema. Method/research designWe reviewed pre-hospital and hospital records for comatose patients surviving to hospital admission after OHCA who had computed tomography (CT) of brain at the time of hospital admission available for inspection. We measured the gray-white ratio (GWR) of X-ray attenuation between the caudate nucleus and posterior limb of the internal capsule, defining severe cerebral edema as GWR < 1.20. We calculated associations between severe cerebral edema and patient or resuscitation variables. ResultsBetween 2010 and 2019, 1340 subjects were admitted of whom 296 (22%) showed severe cerebral edema on initial CT. Subjects with severe edema had lower survival (5/296, 2% vs. 377/1044, 36%). Severe edema was independently associated with total CPR duration, total dose of epinephrine, younger age, non-shockable arrest rhythms, fewer total number of rescue shocks, rearrest after initial return of pulses, and non-cardiac arrest etiology. Prevalence of severe cerebral edema increased from 2% among subjects with 0–10 min of CPR to 31% among subjects with >40 min of CPR. ConclusionCPR duration along with easily measurable clinical and resuscitation characteristics predict early severe cerebral edema after OHCA. Future interventional trials should consider targeting or preventing cerebral edema after prolonged hypoxic-ischemic brain injury especially in patients with high risk clinical features.

P490Time boundaries of three-phase time-sensitive model for ventricular fibrillation cardiac arrest

Abstract Funding Acknowledgements Japan Society for the Promotion of Science (KAKENHI Grant No. 18K09999) Background Recent clinical evidence has suggested that the pathophysiology of ventricular fibrillation (VF) cardiac arrest may consist of three time-sensitive phases, namely electrical, circulatory, and metabolic. According to this model of cardiopulmonary resuscitation (CPR), the optimal treatment of cardiac arrest is phase-specific. The potential survival benefit of bystander cardiopulmonary resuscitation (BCPR) depends in part on ischemic time (i.e., the collapse-to-shock interval), with the greatest benefit occurring during the circulatory (second) phase. However, the time boundaries between phases are not precisely defined in the current literature. Purpose The purpose of the present study was to determine the time boundaries of the three-phase time-sensitive model for VF cardiac arrest. Methods We reviewed 20,741 adult patients with initial VF after witnessed out-of-hospital cardiac arrest from a presumed cardiac origin who were included in the All-Japan Utstein-style registry from 2013 to 2017. We excluded patients who underwent bystander defibrillation prior to arrival of emergency medical services personnel. The study end point was 1-month neurologically intact survival (Cerebral Performance Category scale 1 or 2). Collapse-to-shock interval was defined as the time from collapse to first shock delivery by emergency medical services personnel. Patients were divided into two groups, BCPR (n = 11,606, 56.0%) and non-BCPR (n = 9135, 44.0%), according to whether they had received BCPR or not. Results The rate of 1-month neurologically intact survival in the BCPR group was significantly higher than that in the non-BCPR group (27.9% [3237/11,606] vs 17.9% [1632/9135], P &amp;lt; 0.0001; adjusted odds ratio [OR], 1.90; 95% confidence interval [CI], 1.75–2.07; P &amp;lt; 0.0001). Overall, increased collapse-to-shock interval was associated with significantly decreased adjusted odds of 1-month neurologically intact survival (adjusted OR for each 1-minute increase, 0.94; 95% CI, 0.93–0.95; P &amp;lt; 0.0001). In the BCPR group, the ranges of collapse-to-shock interval that were associated with increased adjusted 1-month neurologically intact survival were from 7 minutes (adjusted OR, 1.95; 95% CI, 1.44–2.63; P &amp;lt; 0.0001) to 17 minutes (adjusted OR, 2.82; 95% CI, 1.62–4.91; P = 0.0002) as compared with those in the non-BCPR group. However, the increase in neurologically intact survival of the BCPR group became statistically insignificant as compared with that of the non-BCPR group when the collapse-to-shock interval was outside these ranges. Conclusions The above-mentioned findings suggest that the time boundaries of the three-phase time-sensitive model for VF cardiac arrest may be as follows: electrical phase, from collapse to &amp;lt;7 minutes; circulatory phase, from 7 to 17 minutes; and metabolic phase, &amp;gt;17 minutes onward from collapse.

910Noise-related malfunctions in modern ICDs during oncologic radiotherapy: a multicentre, real-time, in-vitro observation

Abstract Funding Acknowledgements None Background Direct photon exposure of implantable cardioverter-defibrillators (ICDs) during radiotherapy is still considered not recommended, or even unsafe, by manufacturers and guidelines. The effects of photon beams on ICDs are unpredictable, depending on multiple factors, and electromagnetic interferences (EMIs) may present during exposure. Purpose To evaluate transient ICD malfunctions by direct exposure to doses up to 10 Gy during low-energy radiotherapy, 36 contemporary wireless-enabled ICDs, with at least 4 months to elective replacement indicator (E.R.I.) were evaluated in a realtime in-vitro session. Methods All ICDs had baseline interrogation. Single chamber devices were programmed in the VVI/40 mode and dual or triple chamber devices were programmed in the DDD/40 mode. Rate response function and antitachycardia therapies were disabled, with the ventricular tachycardia (VT)/ventricular fibrillation (VF) detection windows still working. A centering computed tomography was performed to build the corresponding treatment plan and the ICDs were blinded randomized to receive either 2, 5 or 10 Gy exposure by a low photon-energy linear accelerator (6MV) in a homemade water phantom (600 MU/min). The effective dose received by the ICDs was randomly assessed by an in-vivo dosimetry. During radiotherapy course, the devices were observed in a real-time session using manufacturer specific programmer, and ICD function (pacing, sensing, programmed parameters, detection) was recorder by the video camera in the bunker throughout the entire photon exposure. All ICDs had an interrogation session immediately after exposure. Results During radiotherapy course, almost all ICDs (90.9%) recorded major or minor transient EMIs. On detail, 16 ICDs (44.4%) reported EMI-related atrial and/or ventricular oversensing, with base-rate-pacing inhibition and VT/VF detection. 16 ICDs (44.4%) recorded not clinically relevant minor EMIs, and no detections were observed. Only 4 ICDs (11.2%) reported neither transient malfunction nor minor EMIs, withstanding direct radiation exposure. At immediate post-exposure interrogation, the ICDs that recorded major real-time malfunctions had VT/VF detections stored in the device memory. In none of the ICDs spontaneous changes in parameter settings were reported. EMI-related malfunctions occurred regardless of either 2, 5 or 10 Gy photon beam exposure. Conclusions Transient EMIs were observed in most of the contemporary ICDs. To avoid potentially life-threatening ICD malfunctions such as pacing inhibition or inappropriate shock delivery, magnet application on the pocket site or reprogramming in the asynchronous mode are still suggested in ICD patients ongoing even low energy radiotherapy exposure.

Wearable cardioverter-defibrillator as bridging to ICD in pediatric hypertrophic cardiomyopathy with myocardial bridging \u2013 a case report

BackgroundThere is only limited experience with wearable cardioverter-defibrillators (WCD) in pediatric patients. We report on the successful application of a WCD in an adolescent patient with hypertrophic cardiomyopathy and myocardial bridging.Case presentationA 15-year-old girl presented with a history of recurrent syncope, dyspnea, and vertigo with exercise. Diagnostic work-up revealed non-obstructive hypertrophic cardiomyopathy and signs of myocardial ischemia with exercise. Given this high-risk constellation, the patient was scheduled for prophylactic implantation of an implantable cardioverter-defibrillator (ICD). One month after initial presentation and days prior to the planned ICD implantation, the patient collapsed during an episode of sustained ventricular tachycardia (VT) while running. VT was terminated by WCD shock delivery. Following this event, computerized tomography scan revealed myocardial bridging of the left anterior descending coronary artery causing a 90% stenosis in systole. After coronary surgery, life threatening arrhythmias have not recurred, but due to progressive heart failure, the patient underwent successful heart transplantation after 2 years.ConclusionsThe reported case highlights the importance and applicability of WCDs and the potentially malign nature of myocardial bridging in pediatric high-risk patients.

Quality of clinical care provided during simulated pediatric cardiac arrest: a simulation-based study.

We sought to assess compliance to resuscitation guidelines during pediatric simulated cardiac arrests in a pediatric intensive care unit (PICU) and to identify performance gaps to target with future training. In a prospective observational study in a PICU, ten cardiac arrest scenarios were developed for resuscitation training and video recorded. The video recordings were examined for times to start cardiopulmonary resuscitation (CPR), delivery of first shock, CPR quality (rate, depth), length of pauses, chest compression fraction (CCF), ventilation, pulse/rhythm assessment, compressors' rotation, and leader's behaviours. The primary outcome was percentage of events compliant to Pediatric Advance Life Support guidelines. Compliance to guidelines was poor in the 23 simulation events studied. The median [interquartile range] time to start CPR was 29 [16-76] sec and 320 [245-421] sec to deliver the first shock. A total of 306 30-sec epochs of CPR were analyzed; excellent CPR (≥ 90% compressions in target for rate and depth) was achieved in 22 (7%) epochs. More than a quarter of the CPR pauses lasted > 10 seconds (33/127, 26%) with just one task performed in most of them; CCF was ≥ 80% in 19/23 (82.6%) events. Ventilation rate for intubated patients was greater than 10 breaths·min-1 in 15/27 (56%) of one-minute epochs observed. Review of simulated resuscitation events found suboptimal compliance with resuscitation guidelines, particularly the times to starting CPR and delivering the first shock, as well as compression rate and depth.

Implantable cardiac device deactivation at the end of life

Treatment of patients with heart failure is based on drugs, cardiac surgery and implantable cardiac devices to prevent sudden cardiac death (implantable cardioverter-defibrillator [ICD]), to reverse left ventricular dysfunction associated with left bundle branch block (cardiac resynchronization therapy) or mechanical circulatory support in more advanced phases of heart failure (left ventricular assist devices [LVAD]).During the follow-up, patients may die from progression of their underlying heart disease or from non-arrhythmic causes, such as malignancies, multi-organ failure, stroke, etc., without benefits by implanted devices. Patients implanted with ICD could die from non-arrhythmic causes, without appropriate shocks until the last few days or weeks of their life. These events occur roughly in 30% of patients, mainly in the last 24 h before death. LVAD therapy may induce significant complications, such as infections, hemorrhagic stroke, thromboembolism, right ventricular failure. In these cases, inappropriate and even appropriate shock deliveries by ICD can no longer prolong life and may simply lead to pain and reduced quality of life, as well as LVAD may prolong life with painful distress due to complications. Therefore, it appears important to discuss early with the patients and their relatives about deactivation of ICD or LVAD at the end of life. The goal of this paper is to provide an overview of the ethical, clinical and communication issues of cardiac implanted device deactivation, with a special focus on issues associated with advance care planning, which require shared decision-making, including those related to end of life decisions (advance directives). Palliative care should be early implemented, particularly in patients with LVAD.

Conversion from Nonshockable to Shockable Rhythms and Out-of-Hospital Cardiac Arrest Outcomes by Initial Heart Rhythm and Rhythm Conversion Time.

Background The conversion from a nonshockable rhythm (asystole or pulseless electrical activity (PEA)) to a shockable rhythm (pulseless ventricular tachycardia or ventricular fibrillation) may be associated with better out-of-hospital cardiac arrest (OHCA) outcomes. There are insufficient data on the prognostic significance of such conversions by initial heart rhythm and different rhythm conversion time. Methods Among 24,849 adult OHCA patients of presumed cardiac etiology with initial asystole or PEA in the Resuscitation Outcomes Consortium Cardiac Epidemiologic Registry (version 3, 2011–2015), we examined the association of shockable rhythm conversion with prehospital return of spontaneous circulation (ROSC), survival, and favorable functional outcome (modified Rankin Scale score ≤3) at hospital discharge by initial rhythm and rhythm conversion time (time from cardiopulmonary resuscitation (CPR) initiation by emergency medical providers to first shock delivery), using logistic regression adjusting for key clinical characteristics. Results Of 16,516 patients with initial asystole and 8,333 patients with initial PEA, 16% and 20% underwent shockable rhythm conversions; the median rhythm conversion time was 12.0 (IQR: 6.7–18.7) and 13.2 (IQR: 7.0–20.5) min, respectively. No difference was found in odds of prehospital ROSC across rhythm conversion time, regardless of initial heart rhythm. Shockable rhythm conversion was associated with survival and favorable functional outcome at hospital discharge only when occurred during the first 15 min of CPR, for those with initial asystole, or the first 10 min of CPR, for those with initial PEA. The associations between shockable rhythm conversion and outcomes were stronger among those with initial asystole compared with those with initial PEA. Conclusions The conversion from a nonshockable rhythm to a shockable rhythm was associated with better outcomes only when occurred early in initial nonshockable rhythm OHCA, and it has greater prognostic significance when the initial rhythm was asystole.

Innovation in resuscitation: A novel clinical decision display system for advanced cardiac life support.

The Advanced Cardiac Life Support (ACLS) Clinical Decision Display System (CDDS) is a novel application designed to optimize team organization and facilitate decision-making during ACLS resuscitations. We hypothesized that resuscitation teams would more consistently adhere to ACLS guideline time intervals in simulated resuscitation scenarios with the CDDS compared to without. We conducted a simulation-based, non-blinded, randomized, crossover-design study with resuscitation teams comprised of Emergency Medicine physicians, registered nurses, critical care technicians, and paramedics. Each team performed 4 ACLS scenarios in randomized sequences, half with the CDDS and half without. We analyzed the resuscitations and recorded the times of interventions that have defined intervals by ACLS: rhythm checks, epinephrine administration, and shock delivery. In addition, we surveyed each resuscitation team regarding their experience using the CDDS. On average, teams performed rhythm checks 4.9s closer to ACLS guidelines with the CDDS (p=0.0358). Teams were also more consistent; on average, teams reduced the variation of time between consecutive doses of epinephrine by 45% (p=0.0001) and defibrillation by 47% (p<0.0001). Ninety-eight percent of participants indicated they would use the CDDS if available in real cardiac arrests. This study demonstrates that the CDDS improves the accuracy and precision of timed ACLS interventions in a simulated setting. Resuscitation teams were strongly in favor of utilizing the CDDS in clinical practice. Further investigations of the introduction of the platform into real time clinical environments will be needed to assess true efficacy and patient outcomes.

Refractoriness to subcutaneous implantable cardioverter defibrillator after frequent therapies for ventricular fibrillation storms in a Brugada syndrome case

BackgroundThe subcutaneous implantable cardioverter defibrillator (S-ICD) is an alternative to the transvenous implantable cardioverter defibrillator for the prevention of sudden cardiac death. Here, we report a rare case of refractoriness to an S-ICD after frequent therapies for ventricular fibrillation (VF) storms.Case presentationA 24-year-old man underwent a bout of syncope with vomiting and incontinence at home. He was brought to the emergency room and was witnessed to spontaneously go into VF successfully converted by external defibrillation. Previously, he was diagnosed with a type I Brugada electrocardiogram pattern by a pilsicainide administration test in another hospital. Although he had a family history of sudden cardiac death in 3 relatives, including his brother, he was followed closely without any therapies because he had never had an episode of syncope. He was implanted with an S-ICD without any trouble. Seven months later, frequent S-ICD shocks for VF storms occurred. His VF was controlled by using intravenous amiodarone, which was converted to an oral preparation. However, his VF recurred after another 2 months. The analysis of his S-ICD data revealed that 4 consecutive shock deliveries could not terminate his VF and the final shock delivered could fortunately terminate it because of a high defibrillation threshold test (DFT) due to an increasing shock impedance (64 to 90 Ω). First, we performed an epicardial Brugada syndrome ablation and subsequently replaced and repositioned the S-ICD lead from a left to a right parasternal site. After the re-implantation of the S-ICD, the DFT test improved to within normal range. According to the pathological analysis, infiltration of inflammatory cells and extensive fibrosis were confirmed in the subcutaneous tissue around the shock lead and S-ICD body.ConclusionFrequent S-ICD shocks for VF storms might cause various pathological changes around the device and lead to a high DFT.

Outcomes in Brugada Syndrome Patients With Implantable Cardioverter-Defibrillators: Insights From the SGLT2 Registry.

Background and ObjectivesBrugada syndrome (BrS) is a cardiac ion channelopathy with characteristic electrocardiographic patterns, predisposing affected individuals to sudden cardiac death (SCD). Implantable cardioverter-defibrillator (ICD) is used for primary or secondary prevention in BrS, but its use remains controversial amongst low-risk asymptomatic patients. The present study aims to examine indicators for ICD implantation amongst BrS patients with different disease manifestations.MethodsThis study included BrS patients who received ICDs between 1997 and 2018. The cohort was divided into three categories based on presentations before ICD implantation: asymptomatic, syncope, ventricular tachycardia/ventricular fibrillation (VT/VF). Univariate and multivariate Cox-regression analysis were performed to identify independent predictors of appropriate and inappropriate shock delivery.ResultsA total of 136 consecutive patients were included with a median follow-up of 95 (IQR: 80) months. Appropriate shocks were delivered in 34 patients (25.0%) whereas inappropriate shocks were delivered in 24 patients (17.6%). Complications occurred in 30 patients (22.1%). Type 1 Brugada pattern were found to be an independent predictor of appropriate shock delivery, whilst the presence of other arrhythmia was predictive for both appropriate and inappropriate ICD shock delivery under multivariate Cox regression analysis.ConclusionICD therapy is effective for primary and secondary prevention of SCD in BrS. Whilst appropriate shocks occur more frequently in BrS patients presenting with VT/VF, they also occur in asymptomatic patients. Further research in risk stratification can improve patient prognosis while avoid unnecessary ICD implantation.

Causes of Chest Compression Interruptions During Out-of-Hospital Cardiac Arrest Resuscitation.

BackgroundInterruptions in chest compressions contribute to poor outcomes in out‐of‐hospital cardiac arrest. The objective of this retrospective observational cohort study was to characterize the frequency, reasons, and duration of interruptions in chest compressions and to determine if interruptions changed over time.Methods and ResultsAll out‐of‐hospital cardiac arrests treated by the Seattle Fire Department (Seattle, WA, United States) from 2007 to 2016 with capture of recordings from automated external defibrillators and manual defibrillators were included. Compression interruptions >1 second were classified into categories using audio recordings. Among the 3601 eligible out‐of‐hospital cardiac arrests, we analyzed 74 584 minutes, identifying 30 043 pauses that accounted for 6621 minutes (8.9% of total resuscitation duration). The median total interruption duration per case decreased from 115 seconds in 2007 to 72 seconds in 2016 (P<0.0001). Median individual interruption duration decreased from 14 seconds in 2007 to 7 seconds in 2016 (P<0.0001). Among interruptions >10 seconds, median interruption duration decreased from 20 seconds in 2007 to 16 seconds in 2016 (P<0.0001). Cardiac rhythm analysis accounted for most compression interruptions. Manual ECG rhythm analysis and pulse checks accounted for 41.6% of all interruption time (median individual interruption, 8 seconds), automated external defibrillator rhythm analysis for 13.7% (median, 17 seconds), and manual rhythm analysis and shock delivery for 8.0% (median, 9 seconds).ConclusionsMedian duration of chest compression interruptions decreased by half from 2007 to 2016, indicating that care teams can significantly improve performance. Reducing compression interruptions is an evidence‐based benchmark that provides a modifiable process quality improvement goal.

Multimodal Categorical and Dimensional Approaches to Understanding Threat Conditioning and Its Extinction in Individuals With Anxiety Disorders

The Research Domain Criteria project of the National Institute of Mental Health aims to guide neuropsychiatry toward precision medicine. Its inception was partly in response to the overlap of clinical manifestations between different DSM-IV diagnoses within a category. For example, anxiety disorders comprise a DSM-IV category that includes diagnoses that differ from each other but are all characterized by dysregulated fear levels. Whether DSM-IV-based and Research Domain Criteria-based analytic approaches provide distinct or similar information with regard to the fear circuitry of individuals with anxiety disorders has not been directly tested. To use a threat conditioning and extinction protocol to conduct categorical (DSM-IV-based) and dimensional (Research Domain Criteria-based) assessments of psychophysiological, neural, and psychometric responses in individuals with and without anxiety disorders. This cross-sectional study was conducted at the Athinoula A. Martinos Center for Biomedical Imaging at Massachusetts General Hospital in Boston between March 2013 and May 2015. Functional magnetic resonance imaging was used to assess psychophysiological, neural, and psychometric responses among adults aged 18 to 65 years with specific phobia, generalized anxiety disorder, social anxiety disorder, and panic disorder as well as a control group of adults without anxiety disorders. Data were analyzed between May 2018 and April 2019. A 2-day threat conditioning and extinction protocol. Skin conductance responses and blood oxygenated level-dependent responses were measured during the threat and extinction protocol. The categorical analysis was performed by grouping participants based on their primary DSM-IV diagnosis. The dimensional analysis was performed by regrouping participants, irrespective of their diagnoses, based on their skin conductance responses to shock delivery during threat conditioning. This cross-sectional study of 114 adults aged 18 to 65 years included 93 participants (34 men and 59 women; mean [SD] age, 29.7 [11.1] years) with at least 1 anxiety disorder (specific phobia, generalized anxiety disorder, social anxiety disorder, or panic disorder) and 21 participants (11 men and 10 women) without an anxiety disorder. The categorical DSM-IV-based approach indicated that all anxiety disorder groups exhibited hypoactivation in the ventromedial prefrontal cortex during extinction recall (ηp2 = 0.15; P = .004). The Research Domain Criteria-based approach revealed that higher arousal to the unconditioned stimulus was associated with higher threat responses during extinction recall (for skin conductance responses, ηp2 = 0.21; P = .01 and in functional magnetic resonance imaging results, ηp2 = 0.12; P = .02). The direct comparison of DSM-IV-based vs Research Domain Criteria-based results did not yield significant findings (ηp2 values ranged from 0.02 to 0.078; P values ranged from .09 to .98), suggesting no overlap between the approaches. The data obtained from both approaches indicated complementary yet distinct findings. The findings highlight the validity and importance of using both categorical and dimensional approaches to optimize understanding of the etiology and treatment of anxiety symptoms.

Are we all clear? Unintended shocks to caregivers during cardiopulmonary resuscitation.

Although training in basic life support and advanced cardiac life support emphasizes the importance of ensuring that caregivers are “clear” before shock delivery, there will inevitably be circumstances when they are not. However, to our knowledge, device manufacturers do not address how to

Reducing Time to Medical Intervention Through Code Team Reorganization and Simulation Training

Background Cardiac arrest is an acute event with very high morbidity and mortality rates. Ten in 1,000 admitted patients go into cardiac arrest each year and only a quarter of these patients survive to hospital discharge. Code environments are highly complex and require expert coordination among participants to improve patient survival. Despite recognition of the necessary elements for successful resuscitation. Time to medical intervention (TMI) and quality of chest compressions are well documented crucial aspects of a successful code, but other qualities such as demonstrative leadership, clear communication, effective team member interaction, and succinct task completion may also contribute to patient outcomes. Clearly identifying the role of each team member, their responsibilities, and bedside position may improve the success of a code situation. Similarly, pre-defined teams consistently outperform ad hoc teams. Aim The aim of this project was to decrease the time to medical intervention during mock code situations, improve close loop communication and leadership during a code. Methods We achieved our goals by restructuring our code team. First, all members necessary for a code team were identified, their respective roles clearly defined, and the most appropriate bedside positions for each role was carefully selected. Multidisciplinary team leaders were identified and trained as trainers by the core team for this project. Next, random mock codes were called to obtain baseline TMI. After the mock codes for baseline TMI to medical intervention, the trainers then trained the members of their unit on the appropriate roles and specific responsibilities they would be expected to complete during a code situation. Once training was completed, mock codes were randomly called and TMI was recorded. Also, there was a debriefing after these mock codes in which the participants were asked to give their impression of our Quality improvement project on the code team communication, leadership during the mock codes, quietness of the room and their comfort levels with performing the responsibilities of the role they performed. Time to medical intervention in these simulated codes were compared to the average time to medical intervention in our baseline mock codes. Results Post-code debriefings revealed a general sense of improved communication, improved crowd control, and clearer leadership when compared to other code situations the participants had been involved in. Similarly, time to shock delivery or medication administration shortened from the prior average of 2 minutes 46 seconds to 2 minutes 3 seconds, a statistically significant improvement (p-value 0.036). Participants also reported clearer communication, better understanding of their role and improved noise in the code environment. Conclusions Disorganized codes are costly in terms morbidity and post-arrest care. Having well organized codes with clear roles, responsibilities, and positions may decrease the TMI, communication, noise, leadership and improve patient outcomes. Real-life implementation and analysis of this intervention is needed. TMI was defined as the time from when a code is called to the time when the first medication or defibrillation was administered which ever was warranted first.