Dumas F, et al. - Researchers investigated how the amplitude spectrum area (AMSA) waveform measure influences the relationship between increasing burden of chronic health conditions and lower likelihood of survival. They performed a cohort study of patients (≥ 18 years) who suffered ventricular fibrillation out-of-hospital cardiac arrest (OHCA) between 2008-2015 in a metropolitan emergency medical service (EMS) system, identifying 716 eligible patients, 59% of whom had at least one chronic health condition (21.8% with one, 19.6% with two, 10.3% with 3, and 7.3% with ≥4). They noted survival-to-discharge in 45% of patients. As per observations, only a modest part of the correlation between increasing burden of chronic health conditions and lower likelihood of survival after ventricular fibrillation OHCA was mediated by the waveform measure AMSA.