p.8 抽出テキスト

Circulation. 2025;152(suppl 2):S538–S577. DOI: 10.1161/CIR.0000000000001376 October 21, 2025 S545

Wigginton et al Advanced Life Support: 2025 AHA Guidelines for CPR and ECC

in the isolated rabbit heart. J Am Coll Cardiol. 1997;29:831–842. doi: 10.1016/s0735-1097(96)00588-8 9.	 Coult J, Kwok H, Sherman L, Blackwood J, Kudenchuk PJ, Rea TD. Ventricular fibrillation waveform measures combined with prior shock outcome predict defibrillation success during cardiopulmonary resuscitation. J Electrocardiol. 2018;51:99–106. doi: 10.1016/j.jelectrocard.2017.07.016 10.	 Coult J, Blackwood J, Sherman L, Rea TD, Kudenchuk PJ, Kwok H. Ventricular Fibrillation Waveform Analysis During Chest Compressions to Predict Survival From Cardiac Arrest. Circ Arrhythm Electrophysiol. 2019;12:e006924. doi: 10.1161/CIRCEP.118.006924 11.	 Callaway CW, Sherman LD, Mosesso VN Jr., Dietrich TJ, Holt E, Clarkson MC. Scaling exponent predicts defibrillation success for out-of-hospital ventricular fibrillation cardiac arrest. Circulation. 2001;103:1656–1661. doi: 10.1161/01.cir.103.12.1656 12.	 Ruggeri L, Fumagalli F, Bernasconi F, Semeraro F, Meessen J, Blanda A,

Migliari M, Magliocca A, Gordini G, Fumagalli R, et al. Amplitude Spectrum Area of ventricular fibrillation to guide defibrillation: a small open-label, pseudo-randomized controlled multicenter trial. EBioMedicine. 2023;90:104544. doi: 10.1016/j.ebiom.2023.104544

VECTOR CHANGE AND DOUBLE SEQUENTIAL DEFIBRILLATION

Recommendations for Vector Change and Double Sequential Defibrillation COR LOE Recommendations

2b B-R 1.  The usefulness of vector change for adults in cardiac arrest with persisting VF/pVT after ≥3 consecutive shocks has not been established.

2b B-R 2.  The usefulness of double sequential defibrillation for adults in cardiac arrest with persisting VF/ pVT after ≥3 consecutive shocks has not been established.

Synopsis Combined with CPR, successful defibrillation is essential to survival from cardiac arrest caused by VF/VT.1,2 Defibrillation delivers shock energy (joules), creating a current across the thorax from pad-to-pad.3 Its success is influenced by a variety of factors independent of energy setting, including the electrical resistance of tissues encountered (typically highest at the skin-pad interface) that can dramatically reduce current delivery,4–7 pad positions (and resulting shock “vector”) that encompass the heart anatomically8–11 and concomitant high quality CPR. When these are all properly managed, biphasic shock can be highly effective (>75% success) in terminating VF/pVT.12,13 “Shock-resistant” and “shock-refractory” are commonly used to describe VF/pVT that continues to be seen on rhythm checks after repeated shocks. In some cases this is due to true failure of shock to terminate VF/pVT, resulting in ongoing, incessant VF/pVT. Causes of such shock failure can be related to correctable deficiencies in defibrillation technique that are best addressed before employing alternate shock strategies such as pad repositioning (vector change) or double sequential defibrillation (DSD). Conversely, evidence indicates a far more common mechanism for VF/pVT that continues to be seen on post-shock rhythm checks (≈80% of instances) is not due to shock failure, but rather to VF/pVT’s recurrence following successful termination by shock, an event that is obscured by the ensuing period of CPR. When CPR is later paused for rhythm/pulse checks, VF/pVT then seen is attributed to shock failure rather than to its recurrence after successful termination, which is more often the actual case.12,14,15 This distinction is important since recurrent VF/pVT may be better remedied by post-shock rhythm stabilization therapy rather than altering an already successful defibrillation technique. Thus labels like “shock-refractory” can be misleading when they conflate different mechanisms for post-shock VF/ pVT, for which different treatment strategies may be required. Accordingly, we propose using “persisting VF/ pVT” in these guidelines for patients who remain in VF/ pVT arrest after ≥3 consecutive shocks, when its actual mechanism (incessant VF/pVT due to true shock failure vs recurrent VF/pVT following successful termination by shock) is not known with certainty.

Recommendation-Specific Supportive Text 1 and 2.	Prior systematic reviews of low-quality evidence

have not reported benefit from DSD for persisting VF.16–20 Defibrillator pad relocation, called vector change (VC), an inherent feature of DSD, was evaluated in only one trial as a stand-alone measure. That trial (DOSE-VF), compared standard defibrillation, VC, and DSD in patients with cardiac arrest in whom VF continued to be seen on rhythm checks after 3 standard shocks. It found significant improvement in survival at hospital discharge with VC and DSD compared to standard defibrillation by intention-to-treat, but notably not when trial findings were analyzed by the treatment strategy patients actually received.21 Furthermore, in a secondary exploratory analysis a significant survival benefit from DSD was only observed in the 17% of study patients in whom VF was incessant, and not in the vast majority (83%) of patients in whom VF recurred after a successful shock.22 The interval between each sequential “double” shock required for successfully terminating VF has also been shown experimentally23,24 and demonstrated in DOSE-VF itself25 to require a level of precision (separated by milliseconds) unlikely to be consistently achievable by manual activation of two defibrillators. Based on its review, ILCOR’s 2023 International Consensus on CPR and Emergency Cardiovascular Care Science With Treatment Recommendations (CoSTR) judged the overall supportive evidence as relatively weak when issuing “may be considered” recommendations for VC and DSD.26 The adoption of VC or DSD into routine clinical practice for persisting VF/pVT (by whatever mechanism) thus requires further investigation, given its diagnostic and technological requirements.27 These include technologies that can reliably distinguish recurrent from incessant

Downloaded from http://ahajournals.org by on October 7, 2026