Incidence, duration and survival of ventricular fibrillation in out-of-hospital cardiac arrest patients in sweden

Resuscitation. 2000 Mar;44(1):7-17. doi: 10.1016/s0300-9572(99)00155-0.

Abstract

The chance of survival from ventricular fibrillation (VF) is up to ten times higher than those with other cardiac arrest rhythms. To calculate the effect of out-of-hospital resuscitation organisations on survival, it is necessary to know the percentage of cardiac arrest patients initially in VF and the relationship between delay time to defibrillation and survival.

Aim: To study the incidence of VF at the time of cardiac arrest and on first ECG, the duration of VF and the relation between time to defibrillation and survival.

Method: The Swedish Cardiac Arrest Registry has collected standardised reports on out-of-hospital cardiac arrests from ambulance organisations in Sweden, serving 60% of the Swedish population.

Results: In 14065 cases of out-of-hospital cardiac arrest collected between 1990 and 1995, resuscitation was attempted in 10966 cases.

Incidence: The first ECG showed VF in 43% of all patients. The incidence of VF at the time of cardiac arrest was estimated to be 60-70% in all patients and 80-85% in the cases with probable heart disease.

Duration: The estimated disappearance rate of VF was slow. Thirty minutes after collapse approximately 40% of the patients were in VF.

Survival: Overall survival to 1 month was only 1.6% for patients with non-shockable rhythms and 9.5% for patients found in VF. With increasing time to defibrillation, the survival rate fell rapidly from approximately 50% with a minimal delay to 5% at 15 min.

Conclusions: This study suggests a high initial incidence of VF among out-of-hospital cardiac arrest patients and a slow rate of transformation into a non-shockable rhythm. The survival rate with very short delay times to defibrillation was approximately 50%, but decreased rapidly as the delay increased.

MeSH terms

  • Adolescent
  • Adult
  • Age Distribution
  • Aged
  • Aged, 80 and over
  • Cardiopulmonary Resuscitation*
  • Child
  • Child, Preschool
  • Electrocardiography
  • Emergency Medical Services / methods*
  • Female
  • Heart Arrest / diagnosis
  • Heart Arrest / mortality*
  • Heart Arrest / therapy*
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Probability
  • Registries
  • Regression Analysis
  • Risk Factors
  • Sex Distribution
  • Survival Rate
  • Sweden / epidemiology
  • Ventricular Fibrillation / diagnosis
  • Ventricular Fibrillation / epidemiology*
  • Ventricular Fibrillation / therapy*