Nippon Storm Study design

An understanding of the clinical aspects of electrical storm (E‐storms) in patients with implantable cardiac shock devices (ICSDs: ICDs or cardiac resynchronization therapy with defibrillator [CRT‐D]) may provide important information for clinical management of patients with ICSDs. The Nippon Storm Study was organized by the Japanese Heart Rhythm Society (JHRS) and Japanese Society of Electrocardiology and was designed to prospectively collect a variety of data from patients with ICSDs, with a focus on the incidence of E‐storms and clinical conditions for the occurrence of an E‐storm. Forty main ICSD centers in Japan are participating in the present study. From 2002, the JHRS began to collect ICSD patient data using website registration (termed Japanese cardiac defibrillator therapy registration, or JCDTR). This investigation aims to collect data on and investigate the general parameters of patients with ICSDs, such as clinical backgrounds of the patients, purposes of implantation, complications during the implantation procedure, and incidence of appropriate and inappropriate therapies from the ICSD. The Nippon Storm Study was planned as a sub‐study of the JCDTR with focus on E‐storms. We aim to achieve registration of more than 1000 ICSD patients and complete follow‐up data collection, with the assumption of a 5–10% incidence of E‐storms during the 2‐year follow‐up.