Introduction
In December 2019 a new Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) emerged as leading cause of morbidity and mortality in Wuhan, China. Its manifestations known as Coronavirus Disease‐2019 (COVID‐19), suddenly became a major concern for physicians of every specialty (1-2).
COVID‐19 clinical manifestations are mainly respiratory, but major cardiac complications have been reported in a considerable number of cohorts of hospitalized patients (3, 4). A more negative outcome was observed among patients admitted to intensive care units in Italy if cardiovascular risk factors (e.g. hypertension) was present at baseline (5).
Studies have linked COVID‐19 to myocardial injury, suggesting that it could lead to a higher risk of arrhythmic complications (1).
Patients with underling heart disease, especially those considered at higher risk for cardiac arrhythmia, are routinely implanted, according to Guidelines (6-9), with prophylactic implantable cardioverter defibrillator (ICD).
Previous studies have reported seasonal variation, associated with influenza-virus spread, in the occurrence of ventricular arrhythmias (VA) in patients with implantable cardiac defibrillator: during high influenza activity periods, patients were more likely to have a VA treated with shock or anti-tachycardia pacing (ATP) (10, 11).
There is a substantial lack of data from a wider population with history of cardiac diseases on the possible arrhythmogenic effects of the COVID-19 pandemic. The current study aims to: (1) Characterize the burden of ventricular arrhythmia attributable to COVID-19 among patients with an ICD during the epidemic outbreak in Italy, focusing on the period between February 21st and April 5th 2020; and (2) Compare the incidence of VA during the COVID-19 outbreak to that observed during the same timeframe the previous year (February 21st and April 5th 2019).