Risk of Defibrillator Shocks Rises in Extremely Cold Weather

Patients with ventricular tachycardia or ventricular fibrillation are more likely to receive a shock from their implantable cardioverter defibrillator (ICD) in extremely cold weather, according to a study presented at CCC 2016.

Researchers from the University of Manitoba in Winnipeg looked back at all patients at their institution who received a shock from their ICD between 2010 and 2015. They then mapped this information to data on daily temperatures collected from Environment Canada.

On the coldest days, with daily highs below -10 °C, shocks were 25.6% more common than on the warmest days (with daily highs above 10 °C). On cold days (with daily highs between -10 and 10 °C), shocks were 9.3% more common than on the warmest days.

“This finding should result in an increased awareness among health care providers and patients of the relationship between colder temperatures and ventricular arrhythmias,” wrote the researchers in the published abstract from the conference.