# Cardiac arrest in the Australian Alps: A 20-year analysis

## TL;DR

This study analyzed 20 years of data on out-of-hospital cardiac arrests in the Australian Alps, finding they are rare but have high survival rates due to early interventions.

## Contribution

The study provides the first detailed analysis of cardiac arrest incidence and outcomes in an alpine setting in Australia.

## Key findings

- Alpine OHCA occurred in 0.8 cases per million alpine visits over 20 years.
- Alpine OHCA patients were younger and had higher bystander defibrillation rates compared to nonalpine cases.
- Survival to hospital discharge was similar between alpine and nonalpine OHCA patients.

## Abstract

Alpine tourism annually attracts over 100 million visitors globally. Age and cardiovascular comorbidities in alpine tourists are increasing, and rates of out-of-hospital cardiac arrest (OHCA) have been hypothesized to be higher due to exertion and physiological stress.

Cases of alpine OHCA from 2002 to 2021 were identified from the statewide Victorian Ambulance Cardiac Arrest Registry. Alpine and nonalpine OHCA characteristics were compared. Causes of alpine OHCA were obtained from hospital discharge diagnoses and the National Coronial Information System.

Approximately 15.3 million alpine visits were recorded over the time period, during which 13 alpine OHCAs occurred (0.04% of 32,179 OHCAs, 0.8 OHCAs per million alpine visits). Compared with nonalpine OHCAs in a public setting, alpine OHCA patients were younger (median age 52 years vs 63 years, P = .0373), with higher rates of bystander defibrillation (54.5% vs 13.5%, P < .0001). Survival to hospital discharge did not significantly differ between alpine (38.5%) and nonalpine OHCA patients. Ischemic heart disease was the commonest identified cause of alpine OHCA in both survivors and nonsurvivors.

Alpine OHCA is very rare in Australia, accounting for 1 in 5000 OHCAs and fewer than 1 in a million ski field visitors. Despite remoteness and access challenges, alpine OHCA survival is high, driven by prognostically favorable arrest-related factors and coordinated local systems of care prioritizing early bystander intervention.