Search

Background: Despite a promising association between VF waveform characteristics and prognosis after resuscitation, studies with VF-guided treatment have so far not improved outcomes. While driven by the idea that the VF waveform reflects arrest duration, increasing evidence suggests that pre-existent disease-related changes of the myocardium affect ECG-characteristics of VF as well. In this context, we studied the impact of the left ventricular (LV) diameter and mass., Methods: Cohort of 193 ICD-patients with defibrillation testing at the Radboudumc (2010-2014). Surface ECG-recordings (leads I,II,aVF,V1,V3,V6) were analysed to study amplitude and frequency characteristics of the induced VF. Both for LV diameter and mass, patients were categorised in two groups, using echocardiographic data (ASE-guidelines)., Results: In all ECG-leads, dominant and median frequencies were significantly lower in patients with (n=40) than in patients without (n=151) an increased LV diameter. The mean amplitude and amplitude spectrum area (AMSA) did not differ. In contrast, we observed no differences in frequency characteristics in relation to the LV mass, whereas mean amplitude (I,aVF,V3) and AMSA (I,V3) were significantly higher in patients with (n=57) than in patients without (n=120) an increased LV mass., Conclusions: Frequency characteristics of VF were consistently lower in case of an increased LV diameter. Whereas LV mass does not affect the frequency of the VF waveform, amplitudes seem higher with increasing mass. These findings add to the current knowledge of factors that modulate VF characteristics of the surface ECG and provide insight into factors which may be accounted for in future studies on VF-guided resuscitative interventions., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Of the proposed algorithms that provide guidance for in-field termination of resuscitation (TOR) decisions, the guidelines for cardiopulmonary resuscitation (CPR) refer to the basic and advanced life support (ALS)-TOR rules. To assess the potential consequences of implementation of the ALS-TOR rule, we performed a case-by-case evaluation of our in-field termination decisions and assessed the corresponding recommendations of the ALS-TOR rule., Methods: Cohort of non-traumatic out-of-hospital cardiac arrest (OHCA)-patients who were resuscitated by the ALS-practising emergency medical service (EMS) in the Nijmegen area (2008-2011). The ALS-TOR rule recommends termination in case all following criteria are met: unwitnessed arrest, no bystander CPR, no shock delivery, no return of spontaneous circulation (ROSC)., Results: Of the 598 cases reviewed, resuscitative efforts were terminated in the field in 46% and 15% survived to discharge. The ALS-TOR rule would have recommended in-field termination in only 6% of patients, due to high percentages of witnessed arrests (73%) and bystander CPR (54%). In current practice, absence of ROSC was the most important determinant of termination [aOR 35.6 (95% CI 18.3-69.3)]. Weaker associations were found for: unwitnessed and non-public arrests, non-shockable initial rhythms and longer EMS-response times., Conclusion: While designed to optimise hospital transportations, application of the ALS-TOR rule would almost double our hospital transportation rate to over 90% of OHCA-cases due to the favourable arrest circumstances in our region. Prior to implementation of the ALS-TOR rule, local evaluation of the potential consequences for the efficiency of triage is to be recommended and initiatives to improve field-triage for ALS-based EMS-systems are eagerly awaited., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: Ventricular fibrillation (VF) waveform characteristics are associated with cardiac arrest duration and defibrillation success. Recent animal studies found that VF characteristics and shock success also depend on the presence of myocardial infarction (MI). In patients, VF induction after implantable cardioverter defibrillator (ICD) implantation offers a unique setting to study early VF characteristics: we studied the relation with cardiac disease--either presence or absence of a previous MI--and with shock success., Methods: Retrospective cohort study of ICD-patients who underwent defibrillation testing, 117 (63%) with and 69 (37%) without a previous MI. Intracardiac recordings of induced VF were analysed using Fourier analysis., Results: In previous MI-patients, the fundamental frequency and organisation index of the VF signal were significantly lower as compared with patients without a previous MI: 4.9 Hz ± 0.6 vs. 5.2 Hz ± 0.6 (p = 0.005) and 56% ± 10 vs. 60% ± 9 (p = 0.001), respectively. The median frequency was not different (p = 0.25). We found no association between VF characteristics and ICD shock success., Conclusions: In analogy with observations in animals, we found that a history of a previous MI was associated with slower and less organised VF. In our cohort of ICD-patients, early VF waveform characteristics were not associated with shock outcomes. Further study is warranted to determine to what extent VF characteristics are influenced by the underlying aetiology on the one hand, and time delay on the other. These findings could improve insight into the potential value of VF analysis to guide shock delivery., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Although early care in out-of-hospital cardiac arrest has been improved over the past decades, survival remains poor and neurological performance after survival is often impaired. Consequently, new therapies are needed to improve outcome. As thrombotic processes such as acute myocardial infarction or pulmonary embolism are frequent causes of cardiac arrest, therapies like fibrinolysis or percutaneous coronary intervention are of interest. Both therapies can restore coronary and pulmonary perfusion in cardiac arrest patients and, additionally, fibrinolysis might prevent microthrombi to the brain. In this review, the rationale, safety and efficacy of reperfusion therapy in patients with out-of-hospital cardiac arrest will be discussed.